Association of MAOA and COMT gene polymorphisms with palatable food intake in children.

PubMed

Galvão, Ananda C S; Krüger, Raquel C; Campagnolo, Paula D B; Mattevi, Vanessa S; Vitolo, Márcia R; Almeida, Silvana

2012-03-01

Several studies have implicated dopamine (DA) in appetite regulation. The enzymes catechol-o-methyltransferase (COMT) and monoamine oxidase A (MAOA) control DA availability and their genes have well-characterized functional variants. In this study, we examined three polymorphisms in these genes, T941G and MAOAu-VNTR in the MAOA gene and Val158Met in the COMT gene, to investigate how heritable variations in enzymes that determine DA levels might influence food intake and nutritional status. This investigation was a cross-sectional examination of 354 Brazilian children of three to four years old. Polymorphisms were analyzed by PCR-based methods. Means of dietary and anthropometric data were compared among genotypes by one-way analyses of variance or Kruskal Wallis tests. The MAOAu-VNTR and COMT Val158Met polymorphisms were associated with the amount of palatable food intake in boys. Presence of the MAOAu-VNTR*long allele was associated with higher intake of lipid-dense foods (LDF) when compared with the *short allele (P=.009); the amount of sugar-dense foods (SDF) intake was also higher in males carriers of the MAOAu-VNTR *long allele than in carriers of the *short allele (P=.034). In the girls' sample, MAOAu-VNTR polymorphism was not associated with food intake and nutritional status. Carriers of the COMT Val158Met*Val allele presented higher intake of LDF when compared with Met/Met homozygotes (P=.008). This study provides the first indication that genetic variants of enzymes that control DA availability might be involved in determination of the amount of palatable food intake in children. Copyright © 2012 Elsevier Inc. All rights reserved.

Executive control in schizophrenia: a preliminary study on the moderating role of COMT Val158Met for comorbid alcohol and substance use disorders.

PubMed

Carrà, Giuseppe; Nicolini, Gabriella; Crocamo, Cristina; Lax, Annamaria; Amidani, Francesca; Bartoli, Francesco; Castellano, Filippo; Chiorazzi, Alessia; Gamba, Giulia; Papagno, Costanza; Clerici, Massimo

2017-07-01

A functional polymorphism in the catechol-O-methyltransferase (COMT) gene (Val158Met) appears to influence cognition in people with alcohol/substance use disorders (AUD/SUD) and in those with psychosis. To explore the potential moderating effect of these factors, a cross-sectional study was conducted, randomly recruiting subjects with DSM-IV diagnosis of schizophrenia. AUD/SUD was rigorously assessed, as well as COMT Val158Met polymorphism. Executive control functioning was measured using the Intra-Extra Dimensional Set Shift (IED). The effect of a possible interaction between comorbid AUD/SUD and COMT Val158Met polymorphism on IED scores was explored. Subjects with schizophrenia, comorbid AUD/SUD, and MetMet carriers for SNP rs4680 of the COMT gene showed worse performance on IED completed stages scores, as compared with individuals with ValVal genotype. However, among subjects without AUD/SUD, those with the MetMet variant performed better than people carrying ValVal genotype. This study is the first to date examining the impact of COMT on cognition in a highly representative sample of people with schizophrenia and comorbid AUD/SUD. Differential moderating effects of COMT Val/Met genotype variations may similarly influence executive functions in people with schizophrenia and comorbid AUD/SUD.

Analysis of the Association between Catechol-O-Methyltransferase Val158Met and Male Sexual Orientation.

PubMed

Yu, Wei; Tu, Dan; Hong, Fuchang; Wang, Jing; Liu, Xiaoli; Cai, Yumao; Xu, Ruiwei; Zhao, Guanglu; Wang, Feng; Pan, Hong; Wu, Shinan; Feng, Tiejian; Wang, Binbin

2015-09-01

Male sexual orientation is thought to have a genetic component. However, previous studies have failed to generate positive results from among candidate genes. Catechol-O-methyltransferase (COMT), located on chromosome 22, has six exons, spans 27 kb, and encodes a protein of 271 amino acids. COMT has an important role in regulating the embryonic levels of catecholamine neurotransmitters (such as dopamine, norepinephrine, and epinephrine) and estrogens. COMT is also thought to be related to sexual orientation. This study aimed to investigate the relationship between the COMT Val158Met variant and male sexual orientation. We performed association analysis of the COMT gene single nucleotide polymorphism, Val158Met, in 409 homosexual cases and 387 heterosexual control Chinese men. COMT polymorphism status was determined using a polymerase chain reaction-based assay. Polymerase chain reaction was performed to genotype the COMT Val158Met polymorphism. The frequency differences of the genotype and alleles distribution between the male homosexual and control groups. Significant differences, both in genotype and alleles, between male homosexual individuals and controls indicated a genetic component related to male homosexuality. The Val allele recessive model could be an interrelated genetic model of the cause of male homosexuality. The COMT Val158Met variant might be associated with male sexual orientation and a recessive model was suggested. © 2015 International Society for Sexual Medicine.

Association between Catechol-O-Methyltransferase Val158Met (158G/A) Polymorphism and Suicide Susceptibility: A Meta-analysis.

PubMed

Sadeghiyeh, Tahereh; Hosseini Biouki, Fatemeh; Mazaheri, Mahta; Zare-Shehneh, Masoud; Neamatzadeh, Hossein; Poursharif, Zahra

2017-06-24

Common functional Val158Met polymorphism in the Catechol-O-methyltransferase (COMT) gene may have an impact on an individual's susceptibility to suicide, but individually published results are inconclusive. Therefore, we performed this meta-analysis to provide a more precise estimation of the association between COMT 158G/A (COMT Val158Met) polymorphism and suicide susceptibility. A cross-sectional study. This systematic review and meta-analysis is a comprehensive literature search of PubMed, Scopus, Web of Science and Google Scholar databases was conducted on case-control studies published up to Mar 2017. Crude odds ratios (ORs) with 95% confidence intervals (CIs) were calculated. We identified 14 eligible case-control studies, including 2353 suicide attempters and 2593 controls. The pooled results indicated that COMT 158G/A (COMT Val158Met) polymorphism was not significantly associated with increased overall suicide risk. The same results were revealed based on ethnicity, Hardy-Weinberg equilibrium (HWE) status and genotyping technique. However, there was significant association between COMT Val158Met polymorphism and suicide risk among females under the homozygote (AA vs. GG: OR=1.829, 95% CI=1.158-2.889, P=0.010) and recessive (AA vs. AG +GG: OR = 1.787, 95% CI=1.195, 2.671, P=0.005) models, but not among males. COMT 158G/A (COMT Val158Met) polymorphism was associated with suicide susceptibility only in females.

No association between catechol-o-methyltransferase Val108/158Met polymorphism and schizophrenia or its clinical symptomatology in a Mexican population.

PubMed

Tovilla-Zárate, Carlos; Medellín, Beatriz Camarena; Fresán, Ana; López-Narváez, Lilia; Castro, Thelma Beatriz Gonzalez; Juárez Rojop, Isela; Ramírez-Bello, Julián; Genis, Alma; Nicolini, Humberto

2013-02-01

The gene coding for catecol-o-methyltransferase (COMT), participant in the metabolism of catecholamines, has long been implicated as a candidate gene for schizophrenia. We determined the relation of the COMT Val108/158Met polymorphism with schizophrenia or its symptomatology (negative, disorganized and psychotic dimension). We conducted a case-control study comprising 186 patients with schizophrenia and 247 controls. The diagnosis of schizophrenia was established using the DSM-IV criteria for this illness. The clinical symptomatology was assessed through the Scale for the Assessment of Negative Symptoms and the Scale for the Assessment of Positive Symptoms. No significant differences were found in the distribution of alleles (χ2 = 0.01, df = 1, p = 0.90) or genotypes (χ2 = 1.66, df = 2, p = 0.43) between schizophrenic patients and the control group. Multivariate analysis showed that the COMT Val108/158Met polymorphism has no influence in the clinical symptomatology of schizophrenia. Our results showed no association between COMT Val108/158Met and schizophrenia or evidence for an association between COMT and the clinical symptomatology of this illness. This suggests that the COMT gene may not contribute to the risk for schizophrenia among the Mexican population.

Cytochrome P450 1B1 and catechol-O-methyltransferase genetic polymorphisms and breast cancer risk in Chinese women: results from the shanghai breast cancer study and a meta-analysis.

PubMed

Wen, Wanqing; Cai, Qiuyin; Shu, Xiao-Ou; Cheng, Jia-Rong; Parl, Fritz; Pierce, Larry; Gao, Yu-Tang; Zheng, Wei

2005-02-01

Cytochrome P450 1B1 (CYP1B1) and catechol-O-methyltransferase (COMT) are important estrogen-metabolizing enzymes and, thus, genetic polymorphisms of these enzymes may affect breast cancer risk. A population-based case-control study was conducted to assess the association of breast cancer risk with CYP1B1 and COMT polymorphisms. A meta-analysis was done to summarize the findings from this and previous studies. Included in this study were 1,135 incident breast cancer cases diagnosed from August 1996 through March 1998 among female residents of Shanghai and 1,235 randomly selected, age frequency-matched controls from the same general population. The common alleles of the CYP1B1 gene were Arg (79.97%) in codon 48, Ala (80.53%) in codon 119, and Leu (86.57%) in codon 432. The Val allele accounted for 72.46% of the total alleles identified in codon 108/158 of the COMT gene. No overall associations of breast cancer risk were found with any of the single nucleotide polymorphisms described above. This finding was supported by a meta-analysis of all previous published studies. No gene-gene interactions were observed between CYP1B1 and COMT genotypes. The associations of breast cancer risk with factors related to endogenous estrogen exposure, such as years of menstruation and body mass index, were not significantly modified by the CYP1B1 and COMT genotypes. We observed, however, that women who carried one copy of the variant allele in CYP1B1 codons 48 or 119 were less likely to have estrogen receptor-positive breast cancer than those who carried two copies of the corresponding wild-type alleles. The results from this study were consistent with those from most previous studies, indicating no major associations of breast cancer risk with CYP1B1 and COMT polymorphisms.

Predictors of heroin relapse: Personality traits, impulsivity, COMT gene Val158met polymorphism in a 5-year prospective study in Shanghai, China.

PubMed

Su, Hang; Li, Zhibin; Du, Jiang; Jiang, Haifeng; Chen, Zhikang; Sun, Haiming; Zhao, Min

2015-12-01

Relapse is a typical feature of heroin addiction and rooted in genetic and psychological determinants. The aim of this study was to evaluate the effect of personality traits, impulsivity, and COMT gene polymorphism (rs4680) on relapse to heroin use during 5-year follow up. 564 heroin dependent patients were enrolled in compulsory drug rehabilitation center. 12 months prior to their release, personality traits were measured by BIS-11 (Barratt Impulsiveness Scale-11) and Temperament and Character Inventory (TCI). The COMT gene rs4680 polymorphism was genotyped using a DNA sequence detection system. The heroin use status was evaluated for 5 years after discharged. Among the 564 heroin-dependent patients, 500 were followed for 5 years after discharge and 53.0% (n = 265) were considered as relapsed to heroin use according to a strict monitor system. Univariate analysis showed that age, having ever been in methadone maintenance treatment (MMT), the total scores and non-planning scores of BIS-11, and the COMT rs4680 gene variants were different between relapse and abstinent groups. Logistic regression analysis showed higher BIS total score, having ever been in MMT and younger first heroin use age are the predictors of relapse to heroin use during 5 years follow-up, and the COMT rs4680 gene had an interaction with BIS scores. Our findings indicated that the impulsive personality traits, methadone use history, and onset age could predict relapse in heroin-dependent patients during 5 year's follow up. The COMT gene showed a moderational effect in part the relationship of impulsivity with heroin relapse. © 2015 Wiley Periodicals, Inc.

COMT val158met and 5-HTTLPR Genetic Polymorphisms Moderate Executive Control in Cannabis Users

PubMed Central

Verdejo-García, Antonio; Beatriz Fagundo, Ana; Cuenca, Aida; Rodriguez, Joan; Cuyás, Elisabet; Langohr, Klaus; de Sola Llopis, Susana; Civit, Ester; Farré, Magí; Peña-Casanova, Jordi; de la Torre, Rafael

2013-01-01

The adverse effects of cannabis use on executive functions are still controversial, fostering the need for novel biomarkers able to unveil individual differences in the cognitive impact of cannabis consumption. Two common genetic polymorphisms have been linked to the neuroadaptive impact of Δ9-tetrahydrocannabinol (THC) exposure and to executive functions in animals: the catechol-O-methyltransferase (COMT) gene val158met polymorphism and the SLC6A4 gene 5-HTTLPR polymorphism. We aimed to test if these polymorphisms moderate the harmful effects of cannabis use on executive function in young cannabis users. We recruited 144 participants: 86 cannabis users and 58 non-drug user controls. Both groups were genotyped and matched for genetic makeup, sex, age, education, and IQ. We used a computerized neuropsychological battery to assess different aspects of executive functions: sustained attention (CANTAB Rapid Visual Information Processing Test, RVIP), working memory (N-back), monitoring/shifting (CANTAB ID/ED set shifting), planning (CANTAB Stockings of Cambridge, SOC), and decision-making (Iowa Gambling Task, IGT). We used general linear model-based analyses to test performance differences between cannabis users and controls as a function of genotypes. We found that: (i) daily cannabis use is not associated with executive function deficits; and (ii) COMT val158met and 5-HTTLPR polymorphisms moderate the link between cannabis use and executive performance. Cannabis users carrying the COMT val/val genotype exhibited lower accuracy of sustained attention, associated with a more strict response bias, than val/val non-users. Cannabis users carrying the COMT val allele also committed more monitoring/shifting errors than cannabis users carrying the met/met genotype. Finally, cannabis users carrying the 5-HTTLPR s/s genotype had worse IGT performance than s/s non-users. COMT and SLC6A4 genes moderate the impact of cannabis use on executive functions. PMID:23449176

Catechol-O-methyltransferase (COMT) gene modulates private self-consciousness and self-flexibility.

PubMed

Wang, Bei; Ru, Wenzhao; Yang, Xing; Yang, Lu; Fang, Pengpeng; Zhu, Xu; Shen, Guomin; Gao, Xiaocai; Gong, Pingyuan

2016-08-01

Dopamine levels in the brain influence human consciousness. Inspired by the role of Catechol-O-methyltransferase (COMT) in inactivating dopamine in the brain, we investigated to what extent COMT could modulate individual's self-consciousness dispositions and self-consistency by genotyping the COMT Val158Met (rs4680) polymorphism and measuring self-consciousness and self-consistency and congruence in a college student population. The results indicated that COMT Val158Met polymorphism significantly modulated the private self-consciousness. The individuals with Val/Val genotype, corresponding to lower dopamine levels in the brain, were more likely to be aware of their feelings and beliefs. The results also indicated that this polymorphism modulated one's self-flexibility. The individuals with Val/Val genotype showed higher levels of stereotype in self-concept compared with those with Met/Met genotype. These findings suggest that COMT is a predictor of the individual differences in self-consciousness and self-flexibility. Copyright © 2016 Elsevier Inc. All rights reserved.

The COMT Val158Met Polymorphism Is Associated With Response to Add-on Dextromethorphan Treatment in Bipolar Disorder.

PubMed

Lee, Sheng-Yu; Chen, Shiou-Lan; Wang, Tzu-Yun; Chang, Yun-Hsuan; Chen, Po See; Huang, San-Yuan; Tzeng, Nian-Sheng; Wang, Liang-Jen; Lee, I Hui; Chen, Kao Ching; Yang, Yen Kuang; Lu, Ru-Band

2017-02-01

We previously conducted a randomized, double-blind, controlled, 12-week study evaluating the effect of add-on dextromethorphan (DM), a noncompetitive N-methyl-D-aspartate receptor antagonist, on patients with bipolar disorder (BD) treated using valproate (VPA), which showed negative clinical differences. The genetic variation between each individual may be responsible for interindividual differences. The catechol-O-methyltransferase (COMT) gene has been a candidate gene for BD. In the current study, we investigated whether the COMT Val158Met polymorphism predicts treatment response to VPA + add-on DM and to VPA + placebo. Patients with BD (n = 309) undergoing regular VPA treatments were randomly assigned to groups given either add-on DM (30 mg/d) (n = 102), DM (60 mg/d) (n = 101), or placebo (n = 106) for 12 weeks. The Hamilton Depression Rating Scale and Young Mania Rating Scale were used to evaluate clinical response during weeks 0, 1, 2, 4, 8, and 12. The genotypes of the COMT Val158Met polymorphism were determined using polymerase chain reaction plus restriction fragment length polymorphism analysis. To adjust for within-subject dependence over repeated assessments, multiple linear regression with generalized estimating equation methods was used. When stratified by the COMT Val158Met genotypes, significantly greater decreases in Hamilton Depression Rating Scale scores were found in the VPA + DM (30 mg/d) group in patients with the Val/Met genotype (P = 0.008). We conclude that the COMT Val158Met polymorphism may influence responses to DM (30 mg/d) by decreasing depressive symptoms in BD patients.

Association of codon 108/158 catechol-O-methyltransferase gene polymorphism with the psychiatric manifestations of velo-cardio-facial syndrome

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lachman, H.M.; Papolos, D.F.; Veit, S.

Velo-cardio-facial-syndrome (VCFS) is a common congenital disorder associated with typical facial appearance, cleft palate, cardiac defects, and learning disabilities. The majority of patients have an interstitial deletion on chromosome 22q11. In addition to physical abnormalities, a variety of psychiatric illnesses have been reported in patients with VCFS, including schizophrenia, bipolar disorder, and attention deficit hyperactivity disorder. The psychiatric manifestations of VCFS could be due to haploinsufficiency of a gene(s) within 22q11. One candidate that has been mapped to this region is catechol-O-methyltransferase (COMT). We recently identified a polymorphism in the COMT gene that leads to a valine{r_arrow}methionine substitution at aminomore » acid 158 of the membrane-bound form of the enzyme. Homozygosity for COMT158{sup met} leads to a 3- to 4-fold reduction in enzymatic activity, compared with homozygotes for COMT158{sup met}. We now report that in a population of patients with VCFS, there is an apparent association between the low-activity allele, COMT158{sup met}, and the development of bipolar spectrum disorder, and in particular, a rapid-cycling form. 33 refs., 3 tabs.« less

Association between a catechol-o-methyltransferase polymorphism and obsessive-compulsive disorder in the Afrikaner population.

PubMed

Niehaus, D J; Kinnear, C J; Corfield, V A; du Toit, P L; van Kradenburg, J; Moolman-Smook, J C; Weyers, J B; Potgieter, A; Seedat, S; Emsley, R A; Knowles, J A; Brink, P A; Stein, D J

2001-06-01

It has been proposed that the catechol-o-methyl transferase gene (COMT) may play a role in the pathogenesis of obsessive-compulsive disorder (OCD). Whereas studies in a North American population showed that the low activity (L) allele of a functional polymorphism in COMT was associated with OCD in male patients, this result was not supported by studies in a Japanese population. The present association study assessed the risk for OCD conferred by this COMT polymorphism in a geographically different patient group, namely, the relatively genetically homogeneous Afrikaner population of South Africa. Fifty-four unrelated OCD patients and fifty-four sex-matched controls were recruited from the same Afrikaner community. Patients and controls were phenotyped (DSM-IV) and genotyped for a NlaIII polymorphism with H (high activity) or L (low activity) alleles in the COMT gene. The H/L genotype was significantly more common than expected in the OCD patient group (P = 0.0017). Replication studies with related individuals may be useful in discovering factors underpinning the H/L genotype abundance in the Afrikaner population. These results emphasise the need for further studies in genetically homogeneous populations to help define the complex etiology of this disease.

Association analysis of COMT/MTHFR polymorphisms and major depressive disorder in Chinese Han population.

PubMed

Shen, Xinhua; Wu, Yanfeng; Guan, Tiefeng; Wang, Xiaoquan; Qian, Mincai; Lin, Min; Shen, Zhongxia; Sun, Jushui; Zhong, Hua; Yang, Jianhong; Li, Liang; Yuan, Yonggui

2014-06-01

In several previous biochemical and genetic studies, the Val158Met polymorphism of the gene encoding catechol-O-methyltransferase (COMT) and the C677T polymorphism of Methylenetetrahydrofolate reductase (MTHFR) have been suggested to be involved in the pathogenesis as well as the treatment response of major depressive disorder (MDD), but the results have been inconsistent. In this study, we investigate the association of COMT/MTHFR and their interactions with MDD and antidepressant response in Chinese Han population. Three hundred and sixty eight depressed patients who met DSM-IV criteria for MDD were recruited for the study. Two hundred and nineteen normal controls were recruited from the local community. Patients and normal controls were genotyped for the functional COMT val158met and MTHFR C677T polymorphisms. Patients were characterized for clinical response to antidepressant treatment as measured by intra-individual changes of Hamilton Depression (HAMD-17) scores over 6 weeks. The T allele (OR=1.81; CI95%=1.40-2.34, P<0.001) and C/T genotype (OR=3.66; CI95% =2.53-5.28, P<0.001) of MTHFR C677T were significantly different between case and control groups. The COMT Met/Val genotype was more common among depressed individuals than among controls (OR=1.52, CI95%=1.04-2.21, P=0.02). There is disequilibrium in age and sex between case and control groups. Though we control the two variables in the statistic analysis, to be more accurate, we need to increase sample size in further study. Individuals with the genotype COMT Met/Val and MTHFR C/T have more probability of suffering from MDD. However, there is no association between gene polymorphism and treatment response. Copyright © 2014 Elsevier B.V. All rights reserved.

Analysis of functional polymorphisms in three synaptic plasticity-related genes (BDNF, COMT AND UCHL1) in Alzheimer's disease in Colombia.

PubMed

Forero, Diego A; Benítez, Bruno; Arboleda, Gonzalo; Yunis, Juan J; Pardo, Rodrigo; Arboleda, Humberto

2006-07-01

In recent years, it has been proposed that synaptic dysfunction may be an important etiological factor for Alzheimer's disease (AD). This hypothesis has important implications for the analysis of AD genetic risk in case-control studies. In the present work, we analyzed common functional polymorphisms in three synaptic plasticity-related genes (brain-derived neurotrophic factor, BDNF Val66Met; catechol-O-methyl transferase, COMT Val158; ubiquitin carboxyl-terminal hydroxylase, UCHL1 S18Y) in a sample of 102 AD cases and 168 age and sex matched controls living in Bogotá, Colombia. There was not association between UCHL1 polymorphism and AD in our sample. We have found an initial association with BDNF polymorphism in familial cases and with COMT polymorphism in male and sporadic patients. These initial associations were lost after Bonferroni correction for multiple testing. Unadjusted results may be compatible with the expected functional effect of variations in these genes on pathological memory and cognitive dysfunction, as has been implicated in animal and cell models and also from neuropsychological analysis of normal subjects carriers of the AD associated genotypes. An exploration of functional variants in these and in other synaptic plasticity-related genes (a synaptogenomics approach) in independent larger samples will be important to discover new genes associated with AD.

The Val/Met functional polymorphism in COMT confers susceptibility to bipolar disorder: evidence from an association study and a meta-analysis.

PubMed

Zhang, Zhao; Lindpaintner, Klaus; Che, Ronglin; He, Zangdong; Wang, Peng; Yang, Ping; Feng, Guoyin; He, Lin; Shi, Yongyong

2009-10-01

The COMT gene is considered as one of the prominent candidate genes for susceptibility to BP, and most studies focused a functional polymorphism in the gene: the Val/Met polymorphism (rs4680). However, results from these studies are sometimes contradictory, due to small sample size or heterogeneity. In this study, we first investigate the possible association between the Val/Met polymorphism in COMT and bipolar disorder in the Han population, which has never been done before. Then a systematic meta-analysis was conducted to determine if the low-activity allele (Met) increases the risk of BP in different ethnic groups. A total of 478 BP patients and 469 healthy subjects were recruited in our case/control study. MIX software package was employed to perform the meta-analysis on 19 studies after careful search and selection. We observed statistically-significant differences in allele (p = 0.00060) and genotype (p = 0.00203) frequencies between patients and controls in our samples. The meta-analysis also provided a significant pooled OR for association of the Met allele in rs4680 with BP in the total population (p = 0.0223) and in the Asian population (p = 0.0232). Although a significant pooled OR was also found for the Caucasian population (p = 0.0409) after one of the studies as discussed below was removed, the role for Val/Met polymorphism in BP in Caucasian ethnicity was not yet to be confirmed. In conclusion, the low-activity allele (Met) of rs4680 in COMT gene possibly confers risk for bipolar disorder in the Han population, while it needs further evidence for concluding its association with BP in the Caucasian population.

The Flexible Mind Is Associated with the Catechol-O-Methyltransferase (COMT) Val[superscript 158]Met Polymorphism: Evidence for a Role of Dopamine in the Control of Task-Switching

ERIC Educational Resources Information Center

Colzato, Lorenza S.; Waszak, Florian; Nieuwenhuis, Sander; Posthuma, Danielle; Hommel, Bernhard

2010-01-01

Genetic variability related to the catechol-O-methyltransferase (COMT) gene Val[superscript 128]Met polymorphism) has received increasing attention as a possible modulator of cognitive control functions. Recent evidence suggests that the Val[superscript 128]Met genotype may differentially affect cognitive stability and flexibility, in such a way…

Epistasis Analysis for Estrogen Metabolic and Signaling Pathway Genes on Young Ischemic Stroke Patients

PubMed Central

Hsieh, Yi-Chen; Jeng, Jiann-Shing; Lin, Huey-Juan; Hu, Chaur-Jong; Yu, Chia-Chen; Lien, Li-Ming; Peng, Giia-Sheun; Chen, Chin-I; Tang, Sung-Chun; Chi, Nai-Fang; Tseng, Hung-Pin; Chern, Chang-Ming; Hsieh, Fang-I; Bai, Chyi-Huey; Chen, Yi-Rhu; Chiou, Hung-Yi; Jeng, Jiann-Shing; Tang, Sung-Chun; Yeh, Shin-Joe; Tsai, Li-Kai; Kong, Shin; Lien, Li-Ming; Chiu, Hou-Chang; Chen, Wei-Hung; Bai, Chyi-Huey; Huang, Tzu-Hsuan; Chi-Ieong, Lau; Wu, Ya-Ying; Yuan, Rey-Yue; Hu, Chaur-Jong; Sheu, Jau- Jiuan; Yu, Jia-Ming; Ho, Chun-Sum; Chen, Chin-I; Sung, Jia-Ying; Weng, Hsing-Yu; Han, Yu-Hsuan; Huang, Chun-Ping; Chung, Wen-Ting; Ke, Der-Shin; Lin, Huey-Juan; Chang, Chia-Yu; Yeh, Poh-Shiow; Lin, Kao-Chang; Cheng, Tain-Junn; Chou, Chih-Ho; Yang, Chun-Ming; Peng, Giia-Sheun; Lin, Jiann-Chyun; Hsu, Yaw-Don; Denq, Jong-Chyou; Lee, Jiunn-Tay; Hsu, Chang-Hung; Lin, Chun-Chieh; Yen, Che-Hung; Cheng, Chun-An; Sung, Yueh-Feng; Chen, Yuan-Liang; Lien, Ming-Tung; Chou, Chung-Hsing; Liu, Chia-Chen; Yang, Fu-Chi; Wu, Yi-Chung; Tso, An-Chen; Lai, Yu- Hua; Chiang, Chun-I; Tsai, Chia-Kuang; Liu, Meng-Ta; Lin, Ying-Che; Hsu, Yu-Chuan; Chen, Chih-Hung; Sung, Pi-Shan; Chern, Chang-Ming; Hu, Han-Hwa; Wong, Wen-Jang; Luk, Yun-On; Hsu, Li-Chi; Chung, Chih-Ping; Tseng, Hung-Pin; Liu, Chin-Hsiung; Lin, Chun-Liang; Lin, Hung-Chih; Hu, Chaur-Jong

2012-01-01

Background Endogenous estrogens play an important role in the overall cardiocirculatory system. However, there are no studies exploring the hormone metabolism and signaling pathway genes together on ischemic stroke, including sulfotransferase family 1E (SULT1E1), catechol-O-methyl-transferase (COMT), and estrogen receptor α (ESR1). Methods A case-control study was conducted on 305 young ischemic stroke subjects aged ≦ 50 years and 309 age-matched healthy controls. SULT1E1 -64G/A, COMT Val158Met, ESR1 c.454−397 T/C and c.454−351 A/G genes were genotyped and compared between cases and controls to identify single nucleotide polymorphisms associated with ischemic stroke susceptibility. Gene-gene interaction effects were analyzed using entropy-based multifactor dimensionality reduction (MDR), classification and regression tree (CART), and traditional multiple regression models. Results COMT Val158Met polymorphism showed a significant association with susceptibility of young ischemic stroke among females. There was a two-way interaction between SULT1E1 -64G/A and COMT Val158Met in both MDR and CART analysis. The logistic regression model also showed there was a significant interaction effect between SULT1E1 -64G/A and COMT Val158Met on ischemic stroke of the young (P for interaction = 0.0171). We further found that lower estradiol level could increase the risk of young ischemic stroke for those who carry either SULT1E1 or COMT risk genotypes, showing a significant interaction effect (P for interaction = 0.0174). Conclusions Our findings support that a significant epistasis effect exists among estrogen metabolic and signaling pathway genes and gene-environment interactions on young ischemic stroke subjects. PMID:23112845

Genetic Contributions to Age-Related Decline in Executive Function: A 10-Year Longitudinal Study of COMT and BDNF Polymorphisms

PubMed Central

Erickson, Kirk I.; Kim, Jennifer S.; Suever, Barbara L.; Voss, Michelle W.; Francis, B. Magnus; Kramer, Arthur F.

2008-01-01

Genetic variability in the dopaminergic and neurotrophic systems could contribute to age-related impairments in executive control and memory function. In this study we examined whether genetic polymorphisms for catechol-O-methyltransferase (COMT) and brain-derived neurotrophic factor (BDNF) were related to the trajectory of cognitive decline occurring over a 10-year period in older adults. A single nucleotide polymorphism in the COMT (Val158/108Met) gene affects the concentration of dopamine in the prefrontal cortex. In addition, a Val/Met substitution in the pro-domain for BDNF (Val66Met) affects the regulated secretion and trafficking of BDNF with Met carriers showing reduced secretion and poorer cognitive function. We found that impairments over the 10-year span on a task-switching paradigm did not vary as a function of the COMT polymorphism. However, for the BDNF polymorphism the Met carriers performed worse than Val homozygotes at the first testing session but only the Val homozygotes demonstrated a significant reduction in performance over the 10-year span. Our results argue that the COMT polymorphism does not affect the trajectory of age-related executive control decline, whereas the Val/Val polymorphism for BDNF may promote faster rates of cognitive decay in old age. These results are discussed in relation to the role of BDNF in senescence and the transforming impact of the Met allele on cognitive function in old age. PMID:18958211

Impact of DRD2/ANKK1 and COMT Polymorphisms on Attention and Cognitive Functions in Schizophrenia.

PubMed

Nkam, Irene; Ramoz, Nicolas; Breton, Florence; Mallet, Jasmina; Gorwood, Philip; Dubertret, Caroline

2017-01-01

Cognitive deficits such as poor selective attention and executive functions decline have been reported in patients with schizophrenia. Many studies have emphasized the role of dopamine in regulating cognitive functions in the general population as well as in schizophrenia. However, the relationship between cognitive processes, schizophrenia and dopaminergic candidate genes is an original approach given interesting results. The purpose of the current exploratory study was to examine the interaction of dopaminergic genes (coding for dopamine receptor D2, DRD2, and for Catecholamine-O-Methyl-Transferase, COMT) with the diagnostic of schizophrenia in (i) the executive control of attention, (ii) selective attention, and (iii) executive functions. We recruited 52 patients with schizophrenia and 53 healthy controls who performed the Stroop Color-Word Test, the Attention Network Test and the Wisconsin Card Sorting test. Four single nucleotide polymorphisms (SNPs) in the DRD2 gene (rs6275, rs6277, rs2242592 and rs1800497) and two SNPs in the COMT gene (rs4680 and rs165599) have been genotyped. Patients with schizophrenia performed significantly worse than controls in all cognitive performance, taking into account demographic variables. A significant gene by disease interaction was found for the Stroop interference (p = 0.002) for rs6275 of the DRD2 gene. The COMT Val/Val genotype and schizophrenia were associated with increased number of perseverative errors (p = 0.01). In our study, the DRD2 gene is involved in attention while the COMT gene is implicated in executive functions in patients with schizophrenia.

Cortical Dopamine Transmission as Measured with the [11C]FLB 457 – Amphetamine PET Imaging Paradigm Is Not Influenced by COMT Genotype

PubMed Central

Narendran, Rajesh; Tumuluru, Divya; May, Maureen A.; Chowdari, Kodavali V.; Himes, Michael L.; Fasenmyer, Kelli; Frankle, W. Gordon; Nimgaonkar, Vishwajit L.

2016-01-01

Basic investigations link a Val158Met polymorphism (rs4680) in the catechol-O-methyltransferase (COMT) gene to not only its enzymatic activity, but also to its dopaminergic tone in the prefrontal cortex. Previous PET studies have documented the relationship between COMT Val158Met polymorphism and D1 and D2/3 receptor binding potential (BP), and interpreted them in terms of dopaminergic tone. The use of baseline dopamine D1 and D2/3 receptor binding potential (BPND) as a proxy for dopaminergic tone is problematic because they reflect both endogenous dopamine levels (a change in radiotracer's apparent affinity) and receptor density. In this analysis of 31 healthy controls genotyped for the Val158Met polymorphism (Val/Val, Val/Met, and Met/Met), we used amphetamine-induced displacement of [11C]FLB 457 as a direct measure of dopamine release. Our analysis failed to show a relationship between COMT genotype status and prefrontal cortical dopamine release. COMT genotype was also not predictive of baseline dopamine D2/3 receptor BPND. PMID:27322568

Molecular Signatures of Chronic Pain Subtypes

DTIC Science & Technology

2013-01-01

on August 4, 2011. Our project coordinator was in touch with Ms. Lesnow on December 21. We were asked to provide a breakdown of costs for the...49]. A few candidate gene polymorphisms have been linked to pain susceptibility, including catechol-O-methyltranferase ( COMT ). This gene modulates...nociceptive and inflammatory pain and has been linked to temporomandibular joint pain syndromes [50]. Even studies of COMT , however, have demonstrated

Polymorphisms in Dopamine System Genes Are Associated with Individual Differences in Attention in Infancy

ERIC Educational Resources Information Center

Holmboe, Karla; Nemoda, Zsofia; Fearon, R. M. Pasco; Csibra, Gergely; Sasvari-Szekely, Maria; Johnson, Mark H.

2010-01-01

Knowledge about the functional status of the frontal cortex in infancy is limited. This study investigated the effects of polymorphisms in four dopamine system genes on performance in a task developed to assess such functioning, the Freeze-Frame task, at 9 months of age. Polymorphisms in the catechol-O-methyltransferase ("COMT") and the…

COMT Val(158)Met genotype determines the direction of cognitive effects produced by catechol-O-methyltransferase inhibition.

PubMed

Farrell, Sarah M; Tunbridge, Elizabeth M; Braeutigam, Sven; Harrison, Paul J

2012-03-15

Catechol-O-methyltransferase (COMT) metabolizes dopamine. The COMT Val(158)Met polymorphism influences its activity, and multiple neural correlates of this genotype on dopaminergic phenotypes, especially working memory, have been reported. COMT activity can also be regulated pharmacologically by COMT inhibitors. The inverted-U relationship between cortical dopamine signaling and working memory predicts that the effects of COMT inhibition will differ according to COMT genotype. Thirty-four COMT Met(158)Met (Met-COMT) and 33 COMT Val(158)Val (Val-COMT) men were given a single 200-mg dose of the brain-penetrant COMT inhibitor tolcapone or placebo in a randomized, double-blind, between-subjects design. They completed the N-back task of working memory and a gambling task. In the placebo group, Met-COMT subjects outperformed Val-COMT subjects on the 2- back, and they were more risk averse. Tolcapone had opposite effects in the two genotype groups: it worsened N-back performance in Met-COMT subjects but enhanced it in Val-COMT subjects. Tolcapone made Met-COMT subjects less risk averse but Val-COMT subjects more so. In both tasks, tolcapone reversed the baseline genotype differences. Depending on genotype, COMT inhibition can enhance or impair working memory and increase or decrease risky decision making. To our knowledge, the data are the clearest demonstration to date that the direction of effect of a drug can be influenced by a polymorphism in its target gene. The results support the inverted-U model of dopamine function. The findings are of translational relevance, because COMT inhibitors are used in the adjunctive treatment of Parkinson's disease and are under evaluation in schizophrenia and other disorders. Copyright © 2012 Society of Biological Psychiatry. Published by Elsevier Inc. All rights reserved.

[Study of genetic variants in the BDNF, COMT, DAT1 and SERT genes in Colombian children with attention deficit disorder].

PubMed

Ortega-Rojas, Jenny; Arboleda-Bustos, Carlos E; Morales, Luis; Benítez, Bruno A; Beltrán, Diana; Izquierdo, Álvaro; Arboleda, Humberto; Vásquez, Rafael

Attention deficit and hyperactive disorder (ADHD) is highly prevalent among children in Bogota City. Both genetic and environmental factors play a very important role in the etiology of ADHD. However, to date few studies have addressed the association of genetic variants and ADHD in the Colombian population. To test the genetic association between polymorphisms in the DAT1, HTTLPR, COMT and BDNF genes and ADHD in a sample from Bogota City. We genotyped the most common polymorphisms in DAT1, SERT, COMT and BDNF genes associated with ADHD using conventional PCR followed by restriction fragment length polymorphism (RFLP) in 97 trios recruited in a medical center in Bogota. The transmission disequilibrium test (TDT) was used to determine the association between such genetic variants and ADHD. The TDT analysis showed that no individual allele of any variant studied has a preferential transmission. Our results suggest that the etiology of the ADHD may be complex and involves several genetic factors. Further studies in other candidate polymorphisms in a larger sample size will improve our knowledge of the ADHD in Colombian population. Copyright © 2016 Asociación Colombiana de Psiquiatría. Publicado por Elsevier España. All rights reserved.

Catechol-O-methyltransferase gene variation: impact on amygdala response to aversive stimuli.

PubMed

Domschke, Katharina; Baune, Bernhard T; Havlik, Linda; Stuhrmann, Anja; Suslow, Thomas; Kugel, Harald; Zwanzger, Peter; Grotegerd, Dominik; Sehlmeyer, Christina; Arolt, Volker; Dannlowski, Udo

2012-05-01

The functional catechol-O-methyltransferase (COMT) val158met polymorphism has been found to be associated with anxiety disorders and depression as well as with neural correlates of emotional processing, with, however, contradictory results. Thus, the aim of the present study was to re-evaluate the impact of the COMT val158met variant on neural activation correlates of emotional face processing in a sample of healthy probands. In 85 healthy subjects genotyped for the COMT val158met polymorphism, amygdala responses were assessed by means of fMRI. Participants were presented with anger- and fear-relevant faces in a robust emotion-processing paradigm. For exploratory reasons, a supplementary whole-brain analysis of the allele-dose model and a gender-stratified analysis were conducted. The COMT 158val allele showed an allele-dose effect on increased predominantly left-sided amygdala activity in response to fearful/angry facial stimuli (p(uncorrected)=.00004). This effect was independent from the distribution of the frequently studied 5-HTTLPR polymorphism for which a linear effect of S-alleles on amygdala responsiveness was replicated. The influence of COMT 158val alleles was only discerned in the female subgroup of probands. The whole-brain analysis suggested associations of the COMT 158val allele with increased activity in areas of the ventral visual stream and the lateral prefrontal cortex. The present results provide further support for a-potentially female-specific-role of the COMT val158met polymorphism in the genetic and neural underpinnings of anxiety- and depression-related intermediate phenotypes and may aid in further clarifying the differential role of COMT genotype driven dopaminergic tonus in the processing of emotionally salient stimuli. Copyright © 2012 Elsevier Inc. All rights reserved.

The impact of the Catechol-O-methyltransferase Val158Met polymorphism on survival in the general population – the HUNT study

PubMed Central

Hagen, Knut; Stovner, Lars J; Skorpen, Frank; Pettersen, Elin; Zwart, John-Anker

2007-01-01

Background The catechol-O-methyltransferase (COMT) gene contains a functional polymorphism, Val158Met which has been related to common diseases like cancer, psychiatric illness and myocardial infarction. Whether the Val158Met polymorphism is associated with survival has not been evaluated in the general population. The aim of this prospective study was to evaluate the impact of codon 158 COMT gene polymorphism on survival in a population-based cohort. Methods The sample comprised 2979 non-diabetic individuals who participated in the Nord-Trøndelag Health Study (HUNT) in the period 1995–97. The subjects were followed up with respect to mortality throughout year 2004. Results 212 men and 183 women died during the follow up. No association between codon 158 COMT gene polymorphism and survival was found. The unadjusted relative risk of death by non-ischemic heart diseases with Met/Met or Met/Val genotypes was 3.27 (95% confidence interval, 1.19–9.00) compared to Val/Val genotype. When we adjusted for age, gender, smoking, coffee intake and body mass index the relative risk decreased to 2.89 (95% confidence interval, 1.04–8.00). Conclusion During 10 year of follow-up, the Val158Met polymorphism had no impact on survival in a general population. Difference in mortality rates from non-ischemic heart diseases may be incidental and should be evaluated in other studies. PMID:17577421

Analysis of CYP1A1 and COMT polymorphisms in women with cervical cancer.

PubMed

Kleine, J P; Camargo-Kosugi, C M; Carvalho, C V; Silva, F C; Silva, I D C G

2015-12-29

The aim of this case-control study was to obtain a comprehensive panel of genetic polymorphisms present only in genes (cytochrome P-450 1A1--CYP1A1 and catechol-O-methyl transferase--COMT) within the metabolic pathway of sex steroids and determine their possible associations with the presence or absence of cervical cancer. Genotypes of 222 women were analyzed: a) 81 with cancer of the cervix treated at the Cancer Hospital Alfredo Abram, between June 2012 and May 2013, with diagnosis confirmed surgically and/or through histomorphological examination; and b) 141 healthy women who assisted at the Endocrine Gynecology and Climacteric Ambulatory, Department of Gynecology, UNIFESP-EPM. These polymorphisms were detected by polymerase chain reaction amplification-restriction fragment length polymorphism analysis and visualized on 3% agarose gels stained with ethidium bromide. We found a significant association between the frequency of the CYP1A1 polymorphism and the development of cervical cancer. A statistical difference was observed between patient and control groups for CYP1A1 polymorphism genotype distributions (P < 0.05). However, no significant differences were found in the COMT gene polymorphism genotype distributions between the patient and control groups (P > 0.05) or between other risk variables analyzed. The CYP1A1 gene involved in the metabolic pathway of sex steroids might influence the emergence of pathological conditions such as cervical cancer in women who carry a mutated allele, and result in 1.80 and 13.46 times increased risk for women with heterozygous or homozygous mutated genotypes, respectively.

The roles of COMT val158met status and aviation expertise in flight simulator performance and cognitive ability.

PubMed

Kennedy, Q; Taylor, J L; Noda, A; Adamson, M; Murphy, G M; Zeitzer, J M; Yesavage, J A

2011-09-01

The polymorphic variation in the val158met position of the catechol-O-methyltransferase (COMT) gene is associated with differences in executive performance, processing speed, and attention. The purpose of this study is: (1) replicate previous COMT val158met findings on cognitive performance; (2) determine whether COMT val158met effects extend to a real-world task, aircraft navigation performance in a flight simulator; and (3) determine if aviation expertise moderates any effect of COMT val158met status on flight simulator performance. One hundred seventy two pilots aged 41-69 years, who varied in level of aviation training and experience, completed flight simulator, cognitive, and genetic assessments. Results indicate that although no COMT effect was found for an overall measure of flight performance, a positive effect of the met allele was detected for two aspects of cognitive ability: executive functioning and working memory performance. Pilots with the met/met genotype benefited more from increased levels of expertise than other participants on a traffic avoidance measure, which is a component of flight simulator performance. These preliminary results indicate that COMT val158met polymorphic variation can affect a real-world task.

The Roles of COMT val158met Status and Aviation Expertise in Flight Simulator Performance and Cognitive Ability

PubMed Central

Taylor, J. L.; Noda, A.; Adamson, M.; Murphy, G. M.; Zeitzer, J. M.; Yesavage, J. A.

2011-01-01

The polymorphic variation in the val158met position of the catechol-O-methyltransferase (COMT) gene is associated with differences in executive performance, processing speed, and attention. The purpose of this study is: (1) replicate previous COMT val158met findings on cognitive performance; (2) determine whether COMT val158met effects extend to a real-world task, aircraft navigation performance in a flight simulator; and (3) determine if aviation expertise moderates any effect of COMT val158met status on flight simulator performance. One hundred seventy two pilots aged 41–69 years, who varied in level of aviation training and experience, completed flight simulator, cognitive, and genetic assessments. Results indicate that although no COMT effect was found for an overall measure of flight performance, a positive effect of the met allele was detected for two aspects of cognitive ability: executive functioning and working memory performance. Pilots with the met/met genotype benefited more from increased levels of expertise than other participants on a traffic avoidance measure, which is a component of flight simulator performance. These preliminary results indicate that COMT val158met polymorphic variation can affect a real-world task. PMID:21193954

Pulp Sensitivity: Influence of Sex, Psychosocial Variables, COMT Gene, and Chronic Facial Pain.

PubMed

Mladenovic, Irena; Krunic, Jelena; Supic, Gordana; Kozomara, Ruzica; Bokonjic, Dejan; Stojanovic, Nikola; Magic, Zvonko

2018-05-01

The purpose of this study was to evaluate the associations of variability in pulp sensitivity with sex, psychosocial variables, the gene that encodes for the enzyme catechol-O-methyltransferase (COMT), and chronic painful conditions (temporomandibular disorders [TMDs]). The study was composed of 97 subjects (68 women and 29 men aged 20-44 years). The electric (electric pulp tester) and cold (refrigerant spray) stimuli were performed on mandibular lateral incisors. The results were expressed as pain threshold values for electric pulp stimulation (0-80 units) and as pain intensity scores (visual numeric scale from 0-10) for cold stimulation. The Research Diagnostic Criteria for TMD were used to assess TMD, depression, and somatization. DNA extracted from peripheral blood was genotyped for 3 COMT polymorphisms (rs4680, rs6269, and rs165774) using the real-time TaqMan method. Multivariate linear regression was used to investigate the joint effect of the predictor variables (clinical and genetic) on pulp sensitivity (dependent variables). Threshold responses to electric stimuli were related to female sex (P < .01) and the homozygous GG genotype for the rs165774 polymorphism (P < .05). Pain intensity to cold stimuli was higher in TMD patients (P < .01) and tended to be higher in women. Multivariate linear regression identified sex and the rs165774 COMT polymorphism as the determinants of electric pain sensitivity, whereas TMD accounts for the variability in the cold response. Our findings indicate that sex/a COMT gene variant and TMD as a chronic painful condition may contribute to individual variation in electric and cold pulp sensitivity, respectively. Copyright © 2018 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.

Association between the Catechol O-Methyltransferase (COMT) Val158met Polymorphism and Different Dimensions of Impulsivity

PubMed Central

Malloy-Diniz, Leandro Fernandes; Lage, Guilherme Menezes; Campos, Simone Becho; de Paula, Jonas Jardim; de Souza Costa, Danielle; Romano-Silva, Marco Aurélio; de Miranda, Débora Marques; Correa, Humberto

2013-01-01

Background Impulsivity is a multidimensional construct which has been associated with dopaminergic neurotransmission. Nonetheless, until this moment, few studies addressed the relationship between different types of impulsivity and the single nucleotide polymorphism caused by a substitution of valine (val) with methionine (met) in the 158 codon of the Catechol-o-Methyltransferase gene (COMT-val158met). The present study aimed to investigate the association between val158met COMT polymorphism and impulsive behavior measured by two neuropsychological tests. Methodology/Principal Findings We administered two neuropsychological tests, a Continuous Performance Task and the Iowa Gambling Task were applied to 195 healthy participants to characterize their levels of motor, attentional and non-planning impulsivity. Then, subjects were grouped by genotype, and their scores on impulsivity measures were compared. There were no significant differences between group scores on attentional and motor impulsivity. Those participants who were homozygous for the met allele performed worse in the Iowa Gambling Task than val/val and val/met subjects. Conclusions/Significance Our results suggest that met allele of val158met COMT polymorphism is associated with poor performance in decision-making/cognitive impulsivity task. The results reinforce the hypothesis that val and met alleles of the val158met polymorphism show functional dissociation and are related to different prefrontal processes. PMID:24039968

Association of COMT (Val158Met) and BDNF (Val66Met) Gene Polymorphisms with Anxiety, ADHD and Tics in Children with Autism Spectrum Disorder

ERIC Educational Resources Information Center

Gadow, Kenneth D.; Roohi, Jasmin; Devincent, Carla J.; Kirsch, Sarah; Hatchwell, Eli

2009-01-01

The aim of the study is to examine rs4680 ("COMT") and rs6265 ("BDNF") as genetic markers of anxiety, ADHD, and tics. Parents and teachers completed a DSM-IV-referenced rating scale for a total sample of 67 children with autism spectrum disorder (ASD). Both "COMT" (p = 0.06) and "BDNF" (p = 0.07) genotypes were marginally significant for teacher…

Monoamine Oxidase A (MAOA) and Catechol-O-Methyltransferase (COMT) Gene Polymorphisms Interact with Maternal Parenting in Association with Adolescent Reactive Aggression but not Proactive Aggression: Evidence of Differential Susceptibility.

PubMed

Zhang, Wenxin; Cao, Cong; Wang, Meiping; Ji, Linqin; Cao, Yanmiao

2016-04-01

To date, whether and how gene-environment (G × E) interactions operate differently across distinct subtypes of aggression remains untested. More recently, in contrast with the diathesis-stress hypothesis, an alternative hypothesis of differential susceptibility proposes that individuals could be differentially susceptible to environments depending on their genotypes in a "for better and for worse" manner. The current study examined interactions between monoamine oxidase A (MAOA) T941G and catechol-O-methyltransferase (COMT) Val158Met polymorphisms with maternal parenting on two types of aggression: reactive and proactive. Moreover, whether these potential G × E interactions would be consistent with the diathesis-stress versus the differential susceptibility hypothesis was tested. Within the sample of 1399 Chinese Han adolescents (47.2 % girls, M age = 12.32 years, SD = 0.50), MAOA and COMT genes both interacted with positive parenting in their associations with reactive but not proactive aggression. Adolescents with T alleles/TT homozygotes of MAOA gene or Met alleles of COMT gene exhibited more reactive aggression when exposed to low positive parenting, but less reactive aggression when exposed to high positive parenting. These findings provide the first evidence for distinct G × E interaction effects on reactive versus proactive aggression and lend further support for the differential susceptibility hypothesis.

Stressful life events and catechol-O-methyl-transferase (COMT) gene in bipolar disorder.

PubMed

Hosang, Georgina M; Fisher, Helen L; Cohen-Woods, Sarah; McGuffin, Peter; Farmer, Anne E

2017-05-01

A small body of research suggests that gene-environment interactions play an important role in the development of bipolar disorder. The aim of the present study is to contribute to this work by exploring the relationship between stressful life events and the catechol-O-methyl-transferase (COMT) Val 158 Met polymorphism in bipolar disorder. Four hundred eighty-two bipolar cases and 205 psychiatrically healthy controls completed the List of Threatening Experiences Questionnaire. Bipolar cases reported the events experienced 6 months before their worst depressive and manic episodes; controls reported those events experienced 6 months prior to their interview. The genotypic information for the COMT Val 158 Met variant (rs4680) was extracted from GWAS analysis of the sample. The impact of stressful life events was moderated by the COMT genotype for the worst depressive episode using a Val dominant model (adjusted risk difference = 0.09, 95% confidence intervals = 0.003-0.18, P = .04). For the worst manic episodes no significant interactions between COMT and stressful life events were detected. This is the first study to explore the relationship between stressful life events and the COMT Val 158 Met polymorphism focusing solely on bipolar disorder. The results of this study highlight the importance of the interplay between genetic and environmental factors for bipolar depression. © 2017 Wiley Periodicals, Inc.

The Influence of DAT1, COMT, and BDNF Genetic Polymorphisms on Total and Subregional Hippocampal Volumes in Early Onset Heavy Cannabis Users

PubMed Central

Batalla, Albert; Lorenzetti, Valentina; Chye, Yann; Yücel, Murat; Soriano-Mas, Carles; Bhattacharyya, Sagnik; Torrens, Marta; Crippa, José A.S.; Martín-Santos, Rocío

2018-01-01

Abstract Introduction: Hippocampal neuroanatomy is affected by genetic variations in dopaminergic candidate genes and environmental insults, such as early onset of chronic cannabis exposure. Here, we examine how hippocampal total and subregional volumes are affected by cannabis use and functional polymorphisms of dopamine-relevant genes, including the catechol-O-methyltransferase (COMT), dopamine transporter (DAT1), and the brain-derived neurotrophic factor (BDNF) genes. Material and Methods: We manually traced total hippocampal volumes and automatically segmented hippocampal subregions using high-resolution MRI images, and performed COMT, DAT1, and BDNF genotyping in 59 male Caucasian young adults aged 18–30 years. These included 30 chronic cannabis users with early-onset (regular use at <16 years) and 29 age-, education-, and intelligence-matched controls. Results: Cannabis use and dopaminergic gene polymorphism had both distinct and interactive effects on the hippocampus. We found emerging alterations of hippocampal total and specific subregional volumes in cannabis users relative to controls (i.e., CA1, CA2/3, and CA4), and associations between cannabis use levels and total and specific subregional volumes. Furthermore, total hippocampal volume and the fissure subregion were affected by cannabis×DAT1 polymorphism (i.e., 9/9R and in 10/10R alleles), reflecting high and low levels of dopamine availability. Conclusion: These findings suggest that cannabis exposure alters the normal relationship between DAT1 polymorphism and the anatomy of total and subregional hippocampal volumes, and that specific hippocampal subregions may be particularly affected. PMID:29404409

The Influence of DAT1, COMT, and BDNF Genetic Polymorphisms on Total and Subregional Hippocampal Volumes in Early Onset Heavy Cannabis Users.

PubMed

Batalla, Albert; Lorenzetti, Valentina; Chye, Yann; Yücel, Murat; Soriano-Mas, Carles; Bhattacharyya, Sagnik; Torrens, Marta; Crippa, José A S; Martín-Santos, Rocío

2018-01-01

Introduction: Hippocampal neuroanatomy is affected by genetic variations in dopaminergic candidate genes and environmental insults, such as early onset of chronic cannabis exposure. Here, we examine how hippocampal total and subregional volumes are affected by cannabis use and functional polymorphisms of dopamine-relevant genes, including the catechol-O-methyltransferase (COMT), dopamine transporter (DAT1), and the brain-derived neurotrophic factor (BDNF) genes. Material and Methods: We manually traced total hippocampal volumes and automatically segmented hippocampal subregions using high-resolution MRI images, and performed COMT, DAT1, and BDNF genotyping in 59 male Caucasian young adults aged 18-30 years. These included 30 chronic cannabis users with early-onset (regular use at <16 years) and 29 age-, education-, and intelligence-matched controls. Results: Cannabis use and dopaminergic gene polymorphism had both distinct and interactive effects on the hippocampus. We found emerging alterations of hippocampal total and specific subregional volumes in cannabis users relative to controls (i.e., CA1, CA2/3, and CA4), and associations between cannabis use levels and total and specific subregional volumes. Furthermore, total hippocampal volume and the fissure subregion were affected by cannabis×DAT1 polymorphism (i.e., 9/9R and in 10/10R alleles), reflecting high and low levels of dopamine availability. Conclusion: These findings suggest that cannabis exposure alters the normal relationship between DAT1 polymorphism and the anatomy of total and subregional hippocampal volumes, and that specific hippocampal subregions may be particularly affected.

The MAOA, COMT, MTHFR and ESR1 gene polymorphisms are associated with the risk of depression in menopausal women.

PubMed

Różycka, Agata; Słopień, Radosław; Słopień, Agnieszka; Dorszewska, Jolanta; Seremak-Mrozikiewicz, Agnieszka; Lianeri, Margarita; Maciukiewicz, Małgorzata; Warenik-Szymankiewicz, Alina; Grzelak, Teresa; Kurzawińska, Grażyna; Drews, Krzysztof; Klejewski, Andrzej; Jagodziński, Paweł P

2016-02-01

The aim of the study was assessment of a possible relationship between the polymorphisms of the candidate genes participating in the etiology of some neurological and psychiatric disorders and the risk of depression in perimenopausal and postmenopausal women. A total of 167 (54 perimenopausal and 113 postmenopausal) Caucasian women from western Poland, aged 42-67, were recruited as the patient group in the study because of depressive symptoms, and another 321 healthy women (102 perimenopausal and 219 postmenopausal) served as the controls. All study participants were evaluated for climacteric and depressive disorders according to the Kupperman index and Hamilton rating scale for depression (HRSD), respectively. The following candidate genes were selected for the study: 5HTR2A, 5HTR1B, 5HTR2C, TPH1, TPH2, MAOA, COMT, NET, GABRB1, ESR1, MTHFR, MTR and MTHFD1. In each group the frequencies of the polymorphisms were determined using PCR-RFLP analysis. After correcting for Bonferroni multiple tests, we found associations between the MAOA c.1460C>T (SNP 1137070), COMT c.472G>A (SNP 4680), MTHFR c.677C>T (SNP 1801133) and ESR1 454(-351) A>G (SNP 9340799) polymorphisms to mild and moderate depressive symptoms in menopausal women. In the perimenopausal and postmenopausal women, genotype association of the MAOA c.1460 CT and c.1460 CT+TT (OR=1.83; pcorr=0.009 and OR=1.85; pcorr=0.003, resp.), and of the MTHFR c.677 TT and c.677 CT+TT (OR=3.52; pcorr=0.00009 and OR=2.06; pcorr=0.0006, resp.), as well as of the COMT c.472 GA and COMT c.472 GA+AA genotypes (OR=2.23; pcorr=0.03 and OR=2.17; pcorr=0.027, resp.) in the postmenopausal women revealed significantly higher frequencies of these variants in depressed female patients than in controls, whereas the ESR1 454(-351) AG and 454(-351) AG+GG genotypes were associated with lower risk of depression in postmenopausal women (OR=0.48; pcorr=0.012, and OR=0.52; pcorr=0.015, resp.). Our study substantiates the involvement of the MAOA and MTHFR polymorphisms in climacteric depression and offers evidence that the COMT and ESR1 genes may also play a role in the susceptibility to depressive mood in postmenopausal women. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

Two single nucleotide polymorphisms in the CYP17 and COMT Genes--relation to bone mass and longitudinal bone changes in postmenopausal women with or without hormone replacement therapy. The Danish Osteoporosis Prevention Study.

PubMed

Tofteng, C L; Abrahamsen, B; Jensen, J E B; Petersen, S; Teilmann, J; Kindmark, A; Vestergaard, P; Gram, J; Langdahl, B L; Mosekilde, L

2004-08-01

Sex steroids are important physiologic regulators of bone mass, and genes regulating sex steroid production and metabolism are obvious as candidate genes for osteoporosis susceptibility. We present data from a study of 1795 recent postmenopausal women, assigned to either hormone replacement therapy (HRT) or no treatment and followed for 5 years. The association between bone mass measurements and two single nucleotide polymorphisms, a T (A1) to C (A2) transition in the 5'-UTR of the cytochrome P450c17alpha (CYP17) gene and a G (Val) to A (Met) transition in exon 4 of the catechol- O-methyltransferase (COMT) gene, was evaluated. Association with CYP17 genotype was modified by body mass index (BMI). In lean women, individuals homozygous for the CYP17 A2 allele were 1 cm shorter and had lower baseline BMD (bone mineral density), BMC, and CSA (cross sectional area) in the spine and femoral neck than did other women (BMD spine A2A2: 0.975 g/cm2 versus 1.011 g/cm2 in A1A1 + A1A2, P = 0.002). Conversely, an adverse association with A2A2 and bone loss over 5 years seemed present only in overweight women, but differences were small. Response to HRT was not dependent on CYP17 genotype. COMT genotype was not associated with bone mass at baseline, bone loss in untreated women, or response to HRT. In conclusion, the A2 allele of the CYP17 T(27)-C polymorphism is associated with reduced bone mass and bone size in lean perimenopausal women, whereas high BMI protects against this negative association. The COMT G(1947)-A polymorphism is not associated with bone parameters in this study.

Polymorphisms in O-methyltransferase genes are associated with stover cell wall digestibility in European maize (Zea mays L.).

PubMed

Brenner, Everton A; Zein, Imad; Chen, Yongsheng; Andersen, Jeppe R; Wenzel, Gerhard; Ouzunova, Milena; Eder, Joachim; Darnhofer, Birte; Frei, Uschi; Barrière, Yves; Lübberstedt, Thomas

2010-02-12

OMT (O-methyltransferase) genes are involved in lignin biosynthesis, which relates to stover cell wall digestibility. Reduced lignin content is an important determinant of both forage quality and ethanol conversion efficiency of maize stover. Variation in genomic sequences coding for COMT, CCoAOMT1, and CCoAOMT2 was analyzed in relation to stover cell wall digestibility for a panel of 40 European forage maize inbred lines, and re-analyzed for a panel of 34 lines from a published French study. Different methodologies for association analysis were performed and compared. Across association methodologies, a total number of 25, 12, 1, 6 COMT polymorphic sites were significantly associated with DNDF, OMD, NDF, and WSC, respectively. Association analysis for CCoAOMT1 and CCoAOMT2 identified substantially fewer polymorphic sites (3 and 2, respectively) associated with the investigated traits. Our re-analysis on the 34 lines from a published French dataset identified 14 polymorphic sites significantly associated with cell wall digestibility, two of them were consistent with our study. Promising polymorphisms putatively causally associated with variability of cell wall digestibility were inferred from the total number of significantly associated SNPs/Indels. Several polymorphic sites for three O-methyltransferase loci were associated with stover cell wall digestibility. All three tested genes seem to be involved in controlling DNDF, in particular COMT. Thus, considerable variation among Bm3 wildtype alleles can be exploited for improving cell-wall digestibility. Target sites for functional markers were identified enabling development of efficient marker-based selection strategies.

Polymorphisms in O-methyltransferase genes are associated with stover cell wall digestibility in European maize (Zea mays L.)

PubMed Central

2010-01-01

Background OMT (O-methyltransferase) genes are involved in lignin biosynthesis, which relates to stover cell wall digestibility. Reduced lignin content is an important determinant of both forage quality and ethanol conversion efficiency of maize stover. Results Variation in genomic sequences coding for COMT, CCoAOMT1, and CCoAOMT2 was analyzed in relation to stover cell wall digestibility for a panel of 40 European forage maize inbred lines, and re-analyzed for a panel of 34 lines from a published French study. Different methodologies for association analysis were performed and compared. Across association methodologies, a total number of 25, 12, 1, 6 COMT polymorphic sites were significantly associated with DNDF, OMD, NDF, and WSC, respectively. Association analysis for CCoAOMT1 and CCoAOMT2 identified substantially fewer polymorphic sites (3 and 2, respectively) associated with the investigated traits. Our re-analysis on the 34 lines from a published French dataset identified 14 polymorphic sites significantly associated with cell wall digestibility, two of them were consistent with our study. Promising polymorphisms putatively causally associated with variability of cell wall digestibility were inferred from the total number of significantly associated SNPs/Indels. Conclusions Several polymorphic sites for three O-methyltransferase loci were associated with stover cell wall digestibility. All three tested genes seem to be involved in controlling DNDF, in particular COMT. Thus, considerable variation among Bm3 wildtype alleles can be exploited for improving cell-wall digestibility. Target sites for functional markers were identified enabling development of efficient marker-based selection strategies. PMID:20152036

Catechol-O-methyltransferase (COMT) polymorphisms modulate working memory in individuals with schizophrenia and healthy controls.

PubMed

Matsuzaka, Camila T; Christofolini, Denise; Ota, Vanessa K; Gadelha, Ary; Berberian, Arthur A; Noto, Cristiano; Mazzotti, Diego R; Spindola, Leticia M; Moretti, Patricia N; Smith, Marilia A C; Melaragno, Maria I; Belangero, Sintia I; Bressan, Rodrigo A

2017-01-01

Cognitive impairment is a core feature of schizophrenia, related to dopaminergic dysfunction in the prefrontal cortex (PFC). It is hypothesized that functional single nucleotide polymorphism (SNP) rs4680 of the catechol-O-methyltransferase (COMT) gene could mediate the relationship between cognition and dopamine activity in the PFC. Other COMT SNPs could also play a role. We evaluated the role of three COMT SNPs (rs737865, rs165599, and rs4680) in schizophrenia and their impact on three working memory tasks. For genetic association analyses, 212 individuals with schizophrenia and 257 healthy controls (HCs) were selected. The Visual Working Memory (VWM) Task, Keep Track Task, and Letter Memory Task were administered to 133 schizophrenics and 93 HCs. We found a significant association of rs737865, with the GG genotype exerting a protective effect and the GA haplotype (rs4680/rs165599) exerting a risk effect for schizophrenia. COMT rs4680 AA carriers and rs737865 AA carriers scored lowest on the Keep Track Task. When the genotype*group interaction effect was evaluated, rs165599 exerted opposite effects for VWM and Keep Track task performance in patients and controls, with AA carriers scoring lowest on both tests among controls, but highest among patients. These data support the hypothesis that COMT polymorphisms may be associated with schizophrenia and modulate cognition in patients and controls.

The Val158Met COMT polymorphism is a modifier of the age at onset in Parkinson's disease with a sexual dimorphism

PubMed Central

Klebe, Stephan; Golmard, Jean-Louis; Nalls, Michael A; Saad, Mohamad; Singleton, Andrew B; Bras, Jose M; Hardy, John; Simon-Sanchez, Javier; Heutink, Peter; Kuhlenbäumer, Gregor; Charfi, Rim; Klein, Christine; Hagenah, Johann; Gasser, Thomas; Wurster, Isabel; Lesage, Suzanne; Lorenz, Delia; Deuschl, Günther; Durif, Franck; Pollak, Pierre; Damier, Philippe; Tison, François; Durr, Alexandra; Amouyel, Philippe; Lambert, Jean-Charles; Tzourio, Christophe; Maubaret, Cécilia; Charbonnier-Beaupel, Fanny; Tahiri, Khadija; Vidailhet, Marie; Martinez, Maria; Brice, Alexis; Corvol, Jean-Christophe

2013-01-01

The catechol-O-methyltranferase (COMT) is one of the main enzymes that metabolise dopamine in the brain. The Val158Met polymorphism in the COMT gene (rs4680) causes a trimodal distribution of high (Val/Val), intermediate (Val/Met) and low (Met/Met) enzyme activity. We tested whether the Val158Met polymorphism is a modifier of the age at onset (AAO) in Parkinson's disease (PD). The rs4680 was genotyped in a total of 16 609 subjects from five independent cohorts of European and North American origin (5886 patients with PD and 10 723 healthy controls). The multivariate analysis for comparing PD and control groups was based on a stepwise logistic regression, with gender, age and cohort origin included in the initial model. The multivariate analysis of the AAO was a mixed linear model, with COMT genotype and gender considered as fixed effects and cohort and cohort-gender interaction as random effects. COMT genotype was coded as a quantitative variable, assuming a codominant genetic effect. The distribution of the COMT polymorphism was not significantly different in patients and controls (p=0.22). The Val allele had a significant effect on the AAO with a younger AAO in patients with the Val/Val (57.1±13.9, p=0.03) than the Val/Met (57.4±13.9) and the Met/Met genotypes (58.3±13.5). The difference was greater in men (1.9 years between Val/Val and Met/Met, p=0.007) than in women (0.2 years, p=0.81). Thus, the Val158Met COMT polymorphism is not associated with PD in the Caucasian population but acts as a modifier of the AAO in PD with a sexual dimorphism: the Val allele is associated with a younger AAO in men with idiopathic PD. PMID:23408064

MTHFR 677C --> T genotype disrupts prefrontal function in schizophrenia through an interaction with COMT 158Val --> Met.

PubMed

Roffman, Joshua L; Gollub, Randy L; Calhoun, Vince D; Wassink, Thomas H; Weiss, Anthony P; Ho, Beng C; White, Tonya; Clark, Vincent P; Fries, Jill; Andreasen, Nancy C; Goff, Donald C; Manoach, Dara S

2008-11-11

Understanding how risk genes cumulatively impair brain function in schizophrenia could provide critical insights into its pathophysiology. Working memory impairment in schizophrenia has been associated with abnormal dopamine signaling in the prefrontal cortex, which is likely under complex genetic control. The catechol-O-methyltransferase (COMT) 158Val --> Met polymorphism (rs4680), which affects the availability of prefrontal dopamine signaling, consistently stratifies prefrontal activation during working memory performance. However, the low-dopamine COMT 158Val allele does not confer increased risk for schizophrenia, and its effects on prefrontal function are not specific to the disorder. In the setting of other genetic variants influencing prefrontal dopamine signaling, COMT 158Val --> Met genotype may exert disease-specific effects. A second polymorphism, methylenetetrahydrofolate reductase (MTHFR) 677C --> T (rs1801133), has been associated with overall schizophrenia risk and executive function impairment in patients, and may influence dopamine signaling through mechanisms upstream of COMT effects. We found that the hypofunctional 677T variant was associated with decreased working memory load-dependent activation in the prefrontal and insular cortices in 79 schizophrenia patients, but not in 75 demographically matched healthy controls. Further, significant MTHFR x COMT genotype interactions were observed, which differed by diagnostic group: Reduced prefrontal activation was associated with the 677T and 158Val alleles in patients, but with 677C/C and 158Met/Met genotype in controls. These findings are consistent with epistatic effects of the COMT and MTHFR polymorphisms on prefrontal dopamine signaling, and suggest that in schizophrenia patients, the MTHFR 677T allele exacerbates prefrontal dopamine deficiency. The findings also suggest the importance of weighing COMT effects on prefrontal function within the context of MTHFR genotype.

Motor Impulsivity in Parkinson Disease: Associations with COMT and DRD2 polymorphisms

PubMed Central

Ziegler, David A.; Ashourian, Paymon; Wonderlick, Julien S.; Sarokhan, Alison K.; Prelec, Drazen; Scherzer, Clemens R.; Corkin, Suzanne

2017-01-01

Parkinson disease (PD) is an age-related degenerative disease of the brain, characterized by motor, cognitive, and psychiatric symptoms. Neurologists and neuroscientists now understand that several symptoms of the disease, including hallucinations and impulse control behaviors, stem from the dopaminergic medications used to control the motor aspects of PD. Converging evidence from animals and humans suggests that individual differences in the genes that affect the dopamine system influence the response of PD patients to dopaminergic medication. In this study, we tested the hypothesis that patients taking dopamine replacement therapy who carry candidate alleles that increase dopamine signaling exhibit greater amounts of motor impulsivity. We examined the relation between inhibitory ability (measured by the Stop Signal Task) and polymorphisms of COMT Val158Met and DRD2 C957T in patients with idiopathic PD. On the Stop Signal Task, carriers of COMT Val/Met and Met/Met genotypes were more impulsive than Val/Val carriers, but we did not find a link between DRD2 polymorphisms and inhibitory ability. These results support the hypothesis that the Met allele of COMT confers an increased risk for behavioral impulsivity in PD patients, whereas DRD2 polymorphisms appear to be less important in determining whether PD patients exhibit a dopamine overdose in the form of motor impulsivity. PMID:24749760

The influence of COMT Val158Met genotype on the character dimension cooperativeness in healthy females

PubMed Central

Baeken, Chris; Claes, Stephan; De Raedt, Rudi

2014-01-01

Objectives Although the Val158Met catechol-O-methyltransferase (COMT) gene has been linked with the temperament dimension Novelty Seeking (NS), new insights in this polymorphism might point to a major role for character features as well. Given that individual life experiences may influence Val158 and Met158 allele carriers differently it has been suggested that the character trait cooperativeness could be implicated. Case report A homogeneous group of eighty right-handed Caucasian healthy female university students were assessed with the TCI and genotyped for the COMT Val158Met polymorphism (rs4680). Gene determination showed that eighteen were Val158 homozygotes, forty-four Val/Met158 heterozygotes, and eighteen were Met158 homozygotes. All were within the same age range and never documented to have suffered from any neuropsychiatric illness. Bonferroni corrected non-parametric analyses showed that only for the character scale cooperativeness Val158 homozygotes displayed significant higher scores when compared to Met158 homozygotes. No significant differences on cooperativeness scores were found between Val158 and Val/Met158 carriers or between Met158 and Val/Met158 carriers. No differences were observed for the COMT Val158Met polymorphism and the other temperament and character scales. Conclusions Our findings support the assumption that the Val158Met single nucleotide polymorphism (SNP) influences character traits and not only temperament. Our results add to the notion that Val158 homozygotes are considered to be helpful and empathic and it suggest that these cooperativeness character traits are related to the dopaminergic system. PMID:25161818

The influence of COMT Val¹⁵⁸Met genotype on the character dimension cooperativeness in healthy females.

PubMed

Baeken, Chris; Claes, Stephan; De Raedt, Rudi

2014-07-01

Although the Val(158)Met catechol-O-methyltransferase (COMT) gene has been linked with the temperament dimension Novelty Seeking (NS), new insights in this polymorphism might point to a major role for character features as well. Given that individual life experiences may influence Val(158) and Met(158) allele carriers differently it has been suggested that the character trait cooperativeness could be implicated. A homogeneous group of eighty right-handed Caucasian healthy female university students were assessed with the TCI and genotyped for the COMT Val(158)Met polymorphism (rs4680). Gene determination showed that eighteen were Val(158) homozygotes, forty-four Val/Met(158) heterozygotes, and eighteen were Met(158) homozygotes. All were within the same age range and never documented to have suffered from any neuropsychiatric illness. Bonferroni corrected non-parametric analyses showed that only for the character scale cooperativeness Val(158) homozygotes displayed significant higher scores when compared to Met(158) homozygotes. No significant differences on cooperativeness scores were found between Val(158) and Val/Met(158) carriers or between Met(158) and Val/Met(158) carriers. No differences were observed for the COMT Val(158)Met polymorphism and the other temperament and character scales. Our findings support the assumption that the Val(158)Met single nucleotide polymorphism (SNP) influences character traits and not only temperament. Our results add to the notion that Val(158) homozygotes are considered to be helpful and empathic and it suggest that these cooperativeness character traits are related to the dopaminergic system.

The Role of the Catechol-O-Methyltransferase (COMT) Gene in Personality and Related Psychopathological Disorders

PubMed Central

Montag, Christian; Jurkiewicz, Magdalena; Reuter, Martin

2015-01-01

This review provides a short overview of the most significant biologically oriented theories of human personality. Personality concepts of Eysenck, Gray and McNaughton, Cloninger and Panksepp will be introduced and the focal evidence for the heritability of personality will be summarized. In this context, a synopsis of a large number of COMT genetic association studies (with a focus on the COMT Val158Met polymorphism) in the framework of the introduced biologically oriented personality theories will be given. In line with the theory of a continuum model between healthy anxious behavior and related psychopathological behavior, the role of the COMT gene in anxiety disorders will be discussed. A final outlook considers new research strategies such as genetic imaging and epigenetics for a better understanding of human personality. PMID:22483293

Commonly-occurring polymorphisms in the COMT, DRD1 and DRD2 genes influence different aspects of motor sequence learning in humans.

PubMed

Baetu, Irina; Burns, Nicholas R; Urry, Kristi; Barbante, Girolamo Giovanni; Pitcher, Julia B

2015-11-01

Performing sequences of movements is a ubiquitous skill that involves dopamine transmission. However, it is unclear which components of the dopamine system contribute to which aspects of motor sequence learning. Here we used a genetic approach to investigate the relationship between different components of the dopamine system and specific aspects of sequence learning in humans. In particular, we investigated variations in genes that code for the catechol-O-methyltransferase (COMT) enzyme, the dopamine transporter (DAT) and dopamine D1 and D2 receptors (DRD1 and DRD2). COMT and the DAT regulate dopamine availability in the prefrontal cortex and the striatum, respectively, two key regions recruited during learning, whereas dopamine D1 and D2 receptors are thought to be involved in long-term potentiation and depression, respectively. We show that polymorphisms in the COMT, DRD1 and DRD2 genes differentially affect behavioral performance on a sequence learning task in 161 Caucasian participants. The DRD1 polymorphism predicted the ability to learn new sequences, the DRD2 polymorphism predicted the ability to perform a previously learnt sequence after performing interfering random movements, whereas the COMT polymorphism predicted the ability to switch flexibly between two sequences. We used computer simulations to explore potential mechanisms underlying these effects, which revealed that the DRD1 and DRD2 effects are possibly related to neuroplasticity. Our prediction-error algorithm estimated faster rates of connection strengthening in genotype groups with presumably higher D1 receptor densities, and faster rates of connection weakening in genotype groups with presumably higher D2 receptor densities. Consistent with current dopamine theories, these simulations suggest that D1-mediated neuroplasticity contributes to learning to select appropriate actions, whereas D2-mediated neuroplasticity is involved in learning to inhibit incorrect action plans. However, the learning algorithm did not account for the COMT effect, suggesting that prefrontal dopamine availability might affect sequence switching via other, non-learning, mechanisms. These findings provide insight into the function of the dopamine system, which is relevant to the development of treatments for disorders such as Parkinson's disease. Our results suggest that treatments targeting dopamine D1 receptors may improve learning of novel sequences, whereas those targeting dopamine D2 receptors may improve the ability to initiate previously learned sequences of movements. Copyright © 2015 The Authors. Published by Elsevier Inc. All rights reserved.

COMT Val158Met polymorphism influences the susceptibility to framing in decision-making: OFC-amygdala functional connectivity as a mediator.

PubMed

Gao, Xiaoxue; Gong, Pingyuan; Liu, Jinting; Hu, Jie; Li, Yue; Yu, Hongbo; Gong, Xiaoliang; Xiang, Yang; Jiang, Changjun; Zhou, Xiaolin

2016-05-01

Individuals tend to avoid risk in a gain frame, in which options are presented in a positive way, but seek risk in a loss frame, in which the same options are presented negatively. Previous studies suggest that emotional responses play a critical role in this "framing effect." Given that the Met allele of COMT Val158Met polymorphism (rs4680) is associated with the negativity bias during emotional processing, this study investigated whether this polymorphism is associated with individual susceptibility to framing and which brain areas mediate this gene-behavior association. Participants were genotyped, scanned in resting state, and completed a monetary gambling task with options (sure vs risky) presented as potential gains or losses. The Met allele carriers showed a greater framing effect than the Val/Val homozygotes as the former gambled more than the latter in the loss frame. Moreover, the gene-behavior association was mediated by resting-state functional connectivity (RSFC) between orbitofrontal cortex (OFC) and bilateral amygdala. Met allele carriers showed decreased RSFC, thereby demonstrating higher susceptibility to framing than Val allele carriers. These findings demonstrate the involvement of COMT Val158Met polymorphism in the framing effect in decision-making and suggest RSFC between OFC and amygdala as a neural mediator underlying this gene-behavior association. Hum Brain Mapp 37:1880-1892, 2016. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

Association of Catechol-O-Methyltransferase (COMT) Polymorphism and Academic Achievement in a Chinese Cohort

ERIC Educational Resources Information Center

Yeh, Ting-Kuang; Chang, Chun-Yen; Hu, Chung-Yi; Yeh, Ting-Chi; Lin, Ming-Yeh

2009-01-01

Catechol-O-methyltransferase (COMT) is a methylation enzyme that catalyzes the degradation pathway and inactivation of dopamine. It is accepted widely as being involved in the modulation of dopaminergic physiology and prefrontal cortex (PFC) function. The COMT Val158Met polymorphism is associated with variation in COMT activity. COMT 158Met allele…

Modification of COMT-dependent pain sensitivity by psychological stress and sex.

PubMed

Meloto, Carolina B; Bortsov, Andrey V; Bair, Eric; Helgeson, Erika; Ostrom, Cara; Smith, Shad B; Dubner, Ronald; Slade, Gary D; Fillingim, Roger B; Greenspan, Joel D; Ohrbach, Richard; Maixner, William; McLean, Samuel A; Diatchenko, Luda

2016-04-01

Catecholamine-O-methyltransferase (COMT) is a polymorphic gene whose variants affect enzymatic activity and pain sensitivity via adrenergic pathways. Although COMT represents one of the most studied genes in human pain genetics, findings regarding its association with pain phenotypes are not always replicated. Here, we investigated if interactions among functional COMT haplotypes, stress, and sex can modify the effect of COMT genetic variants on pain sensitivity. We tested these interactions in a cross-sectional study, including 2 cohorts, one of 2972 subjects tested for thermal pain sensitivity (Orofacial Pain: Prospective Evaluation and Risk Assessment) and one of 948 subjects with clinical acute pain after motor vehicle collision (post-motor vehicle collision). In both cohorts, the COMT high-pain sensitivity (HPS) haplotype showed robust interaction with stress and number of copies of the HPS haplotype was positively associated with pain sensitivity in nonstressed individuals, but not in stressed individuals. In the post-motor vehicle collision cohort, there was additional modification by sex: the HPS-stress interaction was apparent in males, but not in females. In summary, our findings indicate that stress and sex should be evaluated in association studies aiming to investigate the effect of COMT genetic variants on pain sensitivity.

Depressive symptoms in schizophrenia and dopamine and serotonin gene polymorphisms.

PubMed

Peitl, Vjekoslav; Štefanović, Mario; Karlović, Dalibor

2017-07-03

Although depressive symptoms seem to be frequent in schizophrenia they have received significantly less attention than other symptom domains. As impaired serotonergic and dopaminergic neurotransmission is implicated in the pathogenesis of depression and schizophrenia this study sought to investigate the putative association between several functional gene polymorphisms (SERT 5-HTTLPR, MAO-A VNTR, COMT Val158Met and DAT VNTR) and schizophrenia. Other objectives of this study were to closely examine schizophrenia symptom domains by performing factor analysis of the two most used instruments in this setting (Positive and negative syndrome scale - PANSS and Calgary depression rating scale - CDSS) and to examine the influence of investigated gene polymorphisms on the schizophrenia symptom domains, focusing on depressive scores. A total of 591 participants were included in the study (300 schizophrenic patients and 291 healthy volunteers). 192 (64%) of schizophrenic patients had significant depressive symptoms. Genotype distribution revealed no significant differences regarding all investigated polymorphisms except the separate gender analysis for MAO-A gene polymorphism which revealed significantly more allele 3 carriers in schizophrenic males. Factor analysis of the PANSS scale revealed the existence of five separate factors (symptom domains), while the CDSS scale revealed two distinct factors. Several investigated gene polymorphisms (mostly SERT and MAO-A, but also COMT) significantly influenced two factors from the PANSS (aggressive/impulsive and negative symptoms) and one from the CDSS scale (suicidality), respectively. Depressive symptoms in schizophrenic patients may be influenced by functional gene polymorphisms, especially those implicated in serotonergic neurotransmission. Copyright © 2017 Elsevier Inc. All rights reserved.

Modulation of brain structure by catechol-O-methyltransferase Val(158) Met polymorphism in chronic cannabis users.

PubMed

Batalla, Albert; Soriano-Mas, Carles; López-Solà, Marina; Torrens, Marta; Crippa, José A; Bhattacharyya, Sagnik; Blanco-Hinojo, Laura; Fagundo, Ana B; Harrison, Ben J; Nogué, Santiago; de la Torre, Rafael; Farré, Magí; Pujol, Jesús; Martín-Santos, Rocío

2014-07-01

Neuroimaging studies have shown that chronic consumption of cannabis may result in alterations in brain morphology. Recent work focusing on the relationship between brain structure and the catechol-O-methyltransferase (COMT) gene polymorphism suggests that functional COMT variants may affect brain volume in healthy individuals and in schizophrenia patients. We measured the influence of COMT genotype on the volume of four key regions: the prefrontal cortex, neostriatum (caudate-putamen), anterior cingulate cortex and hippocampus-amygdala complex, in chronic early-onset cannabis users and healthy control subjects. We selected 29 chronic cannabis users who began using cannabis before 16 years of age and matched them to 28 healthy volunteers in terms of age, educational level and IQ. Participants were male, Caucasians aged between 18 and 30 years. All were assessed by a structured psychiatric interview (PRISM) to exclude any lifetime Axis-I disorder according to Diagnostic and Statistical Manual for Mental Disorders-Fourth Edition. COMT genotyping was performed and structural magnetic resonance imaging data was analyzed by voxel-based morphometry. The results showed that the COMT polymorphism influenced the volume of the bilateral ventral caudate nucleus in both groups, but in an opposite direction: more copies of val allele led to lesser volume in chronic cannabis users and more volume in controls. The opposite pattern was found in left amygdala. There were no effects of COMT genotype on volumes of the whole brain or the other selected regions. Our findings support recent reports of neuroanatomical changes associated with cannabis use and, for the first time, reveal that these changes may be influenced by the COMT genotype. © 2013 The Authors, Addiction Biology © 2013 Society for the Study of Addiction.

Influence of Val108/158Met COMT Gene Polymorphism on the Efficacy of Modified Electroconvulsive Therapy in Patients with Treatment Resistant Depression.

PubMed

Lin, Zhaoyu; He, Hongbo; Zhang, Chunping; Wang, Zhijie; Jiang, Miaoling; Li, Qirong; Lan, Xiaochang; Zhang, Minling; Huang, Xiong

2015-04-01

Depression is a common emotional disorder associated with increased risk of suicide and rate of disability. In this double-blinded control study, we tested the efficacy of modified electroconvulsive therapy (MECT) in patients with treatment resistant depression (TRD) using the Hamilton Depression Rating Scale for Depression (HAMD). The total scores of HAMD were found to be significantly decreased after the treatment. The genotyping of catechol-O-methyltransferase (COMT) was carried out with polymerase chain reaction-based testing. Our results demonstrated that frequency of mutant COMT alleles in TRD patients was significantly higher than that of the controls indicating a correlation of the enzyme genotype to the occurrence of TRD. Moreover, the patients homozygous for wild-type COMT gene (G/G) were evidenced to be more sensitive to MECT treatment than those with an heterozygous mutant genotype (A/G).

Convergent genetic modulation of the endocrine stress response involves polymorphic variations of 5-HTT, COMT and MAOA.

PubMed

Jabbi, M; Korf, J; Kema, I P; Hartman, C; van der Pompe, G; Minderaa, R B; Ormel, J; den Boer, J A

2007-05-01

Highly prevalent stress-related disorders such as major depression (MD) are characterised by a dysregulation of the neuroendocrine system. Although heritability for these disorders is high, the role of genes in the underlying pathophysiology is poorly understood. Here, we show that polymorphic variations in genes coding for serotonin transporter (5-HTT), catechol-O-methyl transferase (COMT) and monoamine oxidase A (MAOA) as well as sex differences influence the regulation of hypothalamic-pituitary-adrenal (HPA)-axis response to acute psychological and endocrine challenges. In our sample, the effects of COMT on the release of adrenocorticotrophin hormone (ACTH) depend on the presence of the low-expression MAOA variant in the same individual. By including individuals varying in their degree of susceptibility to MD, we showed evidence of interactions between 5-HTT and MD susceptibility in baseline cortisol, and between MAOA and MD susceptibility in baseline ACTH measures, indicating a role for these genotypes in stable-state endocrine regulation. Collectively, these results indicate that the simultaneous investigation of multiple monoaminergic genes in interaction with gender have to be measured to understand the endocrine regulation of stress. These findings point towards a genetic susceptibility to stress-related disorders.

Dopaminergic and Serotonergic Genotypes and the Subjective Experiences of Hypnosis.

PubMed

Katonai, E R; Szekely, Anna; Vereczkei, A; Sasvari-Szekely, Maria; Bányai, Éva I; Varga, Katalin

2017-01-01

Hypnotizability is related to the Val 158 Met polymorphism of the COMT gene. The authors' aim was to find associations between candidate genes and subjective dimensions of hypnosis; 136 subjects participated in hypnosis and noninvasive DNA sampling. The phenomenological dimensions were tapped by the Archaic Involvement Measure (AIM), the Phenomenology of Consciousness Inventory (PCI), and the Dyadic Interactional Harmony Questionnaire (DIH). The main results were that the "Need of dependence" subscale of AIM was associated with the COMT genotypes. The GG subgroup showed higher scores, whereas AA had below average scores on the majority of the subjective measures. An association between the 5-HTTLPR polymorphism and the intimacy scores on the DIH was also evident. The effects are discussed in the social-psychobiological model of hypnosis.

Genetic polymorphisms in CYP1A1, CYP1B1 and COMT genes in Greenlandic Inuit and Europeans.

PubMed

Ghisari, Mandana; Long, Manhai; Bonefeld-Jørgensen, Eva C

2013-01-01

The Indigenous Arctic population is of Asian descent, and their genetic background is different from the Caucasian populations. Relatively little is known about the specific genetic polymorphisms in genes involved in the activation and detoxification mechanisms of environmental contaminants in Inuit and its relation to health risk. The Greenlandic Inuit are highly exposed to legacy persistent organic pollutants (POPs) such as polychlorinated biphenyls (PCBs) and organochlorine pesticides (OCPs), and an elucidation of gene-environment interactions in relation to health risks is needed. The aim of this study was to determine and compare the genotype and allele frequencies of the cytochrome P450 CYP1A1 Ile462Val (rs1048943), CYP1B1 Leu432Val (rs1056836) and catechol-O-methyltransferase COMT Val158Met (rs4680) in Greenlandic Inuit (n=254) and Europeans (n=262) and explore the possible relation between the genotypes and serum levels of POPs. The genotype and allele frequency distributions of the three genetic polymorphisms differed significantly between the Inuit and Europeans. For Inuit, the genotype distribution was more similar to those reported for Asian populations. We observed a significant difference in serum polychlorinated biphenyl (CB-153) and the pesticide 1,1-dichloro-2,2-bis(p-chlorophenyl)-ethylene (p,p'-DDE) levels between Inuit and Europeans, and for Inuit also associations between the POP levels and genotypes for CYP1A1, CYP1B1 and COMT. Our data provide new information on gene polymorphisms in Greenlandic Inuit that might support evaluation of susceptibility to environmental contaminants and warrant further studies.

Association between the COMT Val158Met polymorphism and fibromyalgia susceptibility and fibromyalgia impact questionnaire score: a meta-analysis.

PubMed

Lee, Young Ho; Kim, Jae-Hoon; Song, Gwan Gyu

2015-01-01

The aim of this study was to explore whether the catechol-O-methyltransferase (COMT) Val158Met polymorphism is associated with susceptibility to fibromyalgia and fibromyalgia impact questionnaire (FIQ) score in fibromyalgia patients. We conducted a meta-analysis of the associations of the COMT Val158Met polymorphism with fibromyalgia risk as well as FIQ score in fibromyalgia patients. A total of 993 fibromyalgia patients and 778 controls from 10 studies on the COMT Val158Met polymorphism and 538 fibromyalgia patients from 5 studies on the COMT Val158Met polymorphism and FIQ score were included in this meta-analysis. The meta-analysis revealed an association between fibromyalgia and the COMT Met/Met + Val/Met genotype in all study subjects (odds ratio (OR) 1.635, 95 % confidence interval (CI) 1.029-2.597, p = 0.037). However, stratification by ethnicity indicated no association between the Met/Met + Val/Met genotype and fibromyalgia in the European and Turkish populations (OR 1.202, 95 % CI 0.876-1.649, p = 0.255; OR 2.132, 95 % CI 0.764-5.949, p = 0.148, respectively). Analysis using other genetic models showed no association between the COMT Val158Met polymorphism and fibromyalgia. The meta-analysis also revealed that the FIQ score was significantly higher in individuals with the COMT Met/Met genotype than in those with the Val/Val genotype [weighted mean difference (WMD) = 14.39, 95 % CI 3.316-25.48, p = 0.011] and the Val/Met genotype (WMD = 5.108, 95 % CI 2.212-4.891, p = 0.021). This meta-analysis identified an association between fibromyalgia risk and the COMT Val158Met polymorphism as well as the FIQ score in fibromyalgia patients.

How to consistently link extraversion and intelligence to the catechol-O-methyltransferase (COMT) gene: on defining and measuring psychological phenotypes in neurogenetic research.

PubMed

Wacker, Jan; Mueller, Erik M; Hennig, Jürgen; Stemmler, Gerhard

2012-02-01

The evidence for associations between genetic polymorphisms and complex behavioral/psychological phenotypes (traits) has thus far been weak and inconsistent. Using the well-studied Val158Met polymorphism of the catechol-O-methyltransferase (COMT) gene as an example, we demonstrate that using theoretical models to guide phenotype definition and measuring the phenotypes of interest with a high degree of specificity reveals strong gene-behavior associations that are consistent with prior work and that would have otherwise gone unnoticed. Only after statistically controlling for irrelevant portions of phenotype variance did we observe strong (Cohen's d = 0.33-0.70) and significant associations between COMT Val158Met and both cognitive and affective traits in a healthy male sample (N = 201) in Study 1: Carriers of the Met allele scored higher in fluid intelligence (reasoning) but lower in both crystallized intelligence (general knowledge) and the agency facet of extraversion. In Study 2, we conceptually replicated the association of COMT Val158Met with the agency facet of extraversion after partialing irrelevant phenotype variance in a female sample (N = 565). Finally, through reanalysis of a large published data set we showed that Met allele carriers also scored higher in indicators of fluid intelligence after partialing verbal fluency. Because the Met allele codes for a less efficient variant of the enzyme COMT, resulting in higher levels of extrasynaptic prefrontal dopamine, these observations provide further support for a role for dopamine in both intelligence and extraversion. More importantly, the present findings have important implications for the definition of psychological phenotypes in neurogenetic research.

BDNF and COMT polymorphisms have a limited association with episodic memory performance or engagement in complex cognitive activity in healthy older adults.

PubMed

Stuart, Kimberley; Summers, Mathew James; Valenzuela, Michael J; Vickers, James C

2014-04-01

Cognitive decline is a major factor in lowering the quality of life in older populations, and contributes substantially to social, economic, and health costs. As humans age, cognitive function decreases differentially, and individual differences in cognitive ageing are likely attributed to a range of causes, including environmental and genetic influences. The current study included 360 participants (240 females and 120 males) aged between 50 and 79years from the Tasmanian Healthy Brain Project. The brain-derived neurotrophic factor (BDNF) Val66Met and Catechol-O-Methyltransferase (COMT) Val158Met polymorphisms were examined for their association with visual and auditory episodic memory performance. The polymorphisms were also investigated for their association with reported life-long engagement in complex cognitive activity using a retrospective questionnaire. Relative to the demographic variables, the gene variations were found to have no association with episodic memory performance, with the exception of the COMT polymorphism on a single measure of auditory memory (RAVLT). Several other studies also demonstrated that these polymorphisms have no, small, or inconsistent effects on memory function. The BDNF Val66Met and COMT Val158Met polymorphisms were also found to be of little significance to active engagement in complex cognitive activity throughout most of the lifespan. An association was detected between BDNF Val66Met and engagement in cognitive activity in early life (p=.04, d=.23), however this did not reach significance when adjusted for multiple comparisons. The biological mechanisms that underlie engagement in cognitive activity are elusive, thus the potential relationship between BDNF Val66Met genotype and early life cognitive engagement warrants further investigation. Crown Copyright © 2014. Published by Elsevier Inc. All rights reserved.

The effects of gender and COMT Val158Met polymorphism on fearful facial affect recognition: a fMRI study.

PubMed

Kempton, Matthew J; Haldane, Morgan; Jogia, Jigar; Christodoulou, Tessa; Powell, John; Collier, David; Williams, Steven C R; Frangou, Sophia

2009-04-01

The functional catechol-O-methyltransferase (COMT Val108/158Met) polymorphism has been shown to have an impact on tasks of executive function, memory and attention and recently, tasks with an affective component. As oestrogen reduces COMT activity, we focused on the interaction between gender and COMT genotype on brain activations during an affective processing task. We used functional MRI (fMRI) to record brain activations from 74 healthy subjects who engaged in a facial affect recognition task; subjects viewed and identified fearful compared to neutral faces. There was no main effect of the COMT polymorphism, gender or genotypexgender interaction on task performance. We found a significant effect of gender on brain activations in the left amygdala and right temporal pole, where females demonstrated increased activations over males. Within these regions, Val/Val carriers showed greater signal magnitude compared to Met/Met carriers, particularly in females. The COMT Val108/158Met polymorphism impacts on gender-related patterns of activation in limbic and paralimbic regions but the functional significance of any oestrogen-related COMT inhibition appears modest.

Pathways to age of onset of heroin use: a structural model approach exploring the relationship of the COMT gene, impulsivity and childhood trauma.

PubMed

Li, Ting; Du, Jiang; Yu, Shunying; Jiang, Haifeng; Fu, Yingmei; Wang, Dongxiang; Sun, Haiming; Chen, Hanhui; Zhao, Min

2012-01-01

The interaction of the association of dopamine genes, impulsivity and childhood trauma with substance abuse remains unclear. To clarify the impacts and the interactions of the Catechol -O-methyltransferase (COMT) gene, impulsivity and childhood trauma on the age of onset of heroin use among heroin dependent patients in China. 202 male and 248 female inpatients who meet DSM-IV criteria of heroin dependence were enrolled. Impulsivity and childhood trauma were measured using BIS-11 (Barratt Impulsiveness Scale-11) and ETISR-SF (Early Trauma Inventory Self Report-Short Form). The single nucleotide polymorphism (SNP) rs737866 on the COMT gene-which has previously been associated with heroin abuse, was genotyped using a DNA sequence detection system. Structural equations model was used to assess the interaction paths between these factors and the age of onset of heroin use. Chi-square test indicated the individuals with TT allele have earlier age of onset of heroin use than those with CT or CC allele. In the correlation analysis, the severity of childhood trauma was positively correlated to impulsive score, but both of them were negatively related to the age of onset of heroin use. In structure equation model, both the COMT gene and childhood trauma had impacts on the age of onset of heroin use directly or via impulsive personality. Our findings indicated that the COMT gene, impulsive personality traits and childhood trauma experience were interacted to impact the age of onset of heroin use, which play a critical role in the development of heroin dependence. The impact of environmental factor was greater than the COMT gene in the development of heroin dependence.

Genetic polymorphisms in CYP1A1, CYP1B1 and COMT genes in Greenlandic Inuit and Europeans

PubMed Central

Ghisari, Mandana; Long, Manhai; Bonefeld-Jørgensen, Eva C.

2013-01-01

Background The Indigenous Arctic population is of Asian descent, and their genetic background is different from the Caucasian populations. Relatively little is known about the specific genetic polymorphisms in genes involved in the activation and detoxification mechanisms of environmental contaminants in Inuit and its relation to health risk. The Greenlandic Inuit are highly exposed to legacy persistent organic pollutants (POPs) such as polychlorinated biphenyls (PCBs) and organochlorine pesticides (OCPs), and an elucidation of gene–environment interactions in relation to health risks is needed. Objectives The aim of this study was to determine and compare the genotype and allele frequencies of the cytochrome P450 CYP1A1 Ile462Val (rs1048943), CYP1B1 Leu432Val (rs1056836) and catechol-O-methyltransferase COMT Val158Met (rs4680) in Greenlandic Inuit (n=254) and Europeans (n=262) and explore the possible relation between the genotypes and serum levels of POPs. Results The genotype and allele frequency distributions of the three genetic polymorphisms differed significantly between the Inuit and Europeans. For Inuit, the genotype distribution was more similar to those reported for Asian populations. We observed a significant difference in serum polychlorinated biphenyl (CB-153) and the pesticide 1,1-dichloro-2,2-bis(p-chlorophenyl)-ethylene (p,p′-DDE) levels between Inuit and Europeans, and for Inuit also associations between the POP levels and genotypes for CYP1A1, CYP1B1 and COMT. Conclusion Our data provide new information on gene polymorphisms in Greenlandic Inuit that might support evaluation of susceptibility to environmental contaminants and warrant further studies. PMID:23785672

Catechol-O-methyltransferase gene haplotypes in Mexican and Spanish patients with fibromyalgia

PubMed Central

Vargas-Alarcón, Gilberto; Fragoso, José-Manuel; Cruz-Robles, David; Vargas, Angélica; Vargas, Alfonso; Lao-Villadóniga, José-Ignacio; García-Fructuoso, Ferrán; Ramos-Kuri, Manuel; Hernández, Fernando; Springall, Rashidi; Bojalil, Rafael; Vallejo, Maite; Martínez-Lavín, Manuel

2007-01-01

Autonomic dysfunction is frequent in patients with fibromyalgia (FM). Heart rate variability analyses have demonstrated signs of ongoing sympathetic hyperactivity. Catecholamines are sympathetic neurotransmitters. Catechol-O-methyltransferase (COMT), an enzyme, is the major catecholamine-clearing pathway. There are several single-nucleotide polymorphisms (SNPs) in the COMT gene associated with the different catecholamine-clearing abilities of the COMT enzyme. These SNPs are in linkage disequilibrium and segregate as 'haplotypes'. Healthy females with a particular COMT gene haplotype (ACCG) producing a defective enzyme are more sensitive to painful stimuli. The objective of our study was to define whether women with FM, from two different countries (Mexico and Spain), have the COMT gene haplotypes that have been previously associated with greater sensitivity to pain. All the individuals in the study were female. Fifty-seven Mexican patients and 78 Spanish patients were compared with their respective healthy control groups. All participants filled out the Fibromyalgia Impact Questionnaire (FIQ). Six COMT SNPs (rs2097903, rs6269, rs4633, rs4818, rs4680, and rs165599) were genotyped from peripheral blood DNA. In Spanish patients, there was a significant association between three SNPs (rs6269, rs4818, and rs4680) and the presence of FM when compared with healthy controls. Moreover, in Spanish patients with the 'high pain sensitivity' haplotype (ACCG), the disease, as assessed by the FIQ, was more severe. By contrast, Mexican patients displayed only a weak association between rs6269 and rs165599, and some FIQ subscales. In our group of Spanish patients, there was an association between FM and the COMT haplotype previously associated with high pain sensitivity. This association was not observed in Mexican patients. Studies with a larger sample size are needed in order to verify or amend these preliminary results. PMID:17961261

Why Some People Discount More than Others: Baseline Activation in the Dorsal PFC Mediates the Link between COMT Genotype and Impatient Choice

PubMed Central

Gianotti, Lorena R. R.; Figner, Bernd; Ebstein, Richard P.; Knoch, Daria

2012-01-01

Individuals differ widely in how steeply they discount future rewards. The sources of these stable individual differences in delay discounting (DD) are largely unknown. One candidate is the COMT Val158Met polymorphism, known to modulate prefrontal dopamine levels and affect DD. To identify possible neural mechanisms by which this polymorphism may contribute to stable individual DD differences, we measured 73 participants’ neural baseline activation using resting electroencephalogram (EEG). Such neural baseline activation measures are highly heritable and stable over time, thus an ideal endophenotype candidate to explain how genes may influence behavior via individual differences in neural function. After EEG-recording, participants made a series of incentive-compatible intertemporal choices to determine the steepness of their DD. We found that COMT significantly affected DD and that this effect was mediated by baseline activation level in the left dorsal prefrontal cortex (DPFC): (i) COMT had a significant effect on DD such that the number of Val alleles was positively correlated with steeper DD (higher numbers of Val alleles means greater COMT activity and thus lower dopamine levels). (ii) A whole-brain search identified a cluster in left DPFC where baseline activation was correlated with DD; lower activation was associated with steeper DD. (iii) COMT had a significant effect on the baseline activation level in this left DPFC cluster such that a higher number of Val alleles was associated with lower baseline activation. (iv) The effect of COMT on DD was explained by the mediating effect of neural baseline activation in the left DPFC cluster. Our study thus establishes baseline activation level in left DPFC as salient neural signature in the form of an endophenotype that mediates the link between COMT and DD. PMID:22586360

Polymorphisms of Estrogen Metabolism-Related Genes and Prostate Cancer Risk in Two Populations of African Ancestry

PubMed Central

Emeville, Elise; Ferdinand, Séverine; Punga, Augustin; Lufuma, Simon; Blanchet, Pascal; Romana, Marc; Multigner, Luc

2016-01-01

Background Estrogens are thought to play a critical role in prostate carcinogenesis. It has been suggested that polymorphisms of genes encoding enzymes involved in estrogen metabolism are risk factors for prostate cancer. However, few studies have been performed on populations of African ancestry, which are known to have a high risk of prostate cancer. Objective We investigated whether functional polymorphisms of CYP17, CYP19, CYP1B1, COMT and UGT1A1 affected the risk of prostate cancer in two different populations of African ancestry. Methods In Guadeloupe (French West Indies), we compared 498 prostate cancer patients and 565 control subjects. In Kinshasa (Democratic Republic of Congo), 162 prostate cancer patients were compared with 144 controls. Gene polymorphisms were determined by the SNaPshot technique or short tandem repeat PCR analysis. Logistic regression was used to estimate adjusted odds ratios (OR) and 95% confidence intervals (CI). Results The AA genotype and the A allele of rs4680 (COMT) appeared to be inversely associated with the risk of prostate cancer in adjusted models for both Afro-Caribbean and native African men. For the A allele, a significant inverse association was observed among cases with low-grade Gleason scores and localized clinical stage, in both populations. Conclusions These preliminary results support the hypothesis that polymorphisms of genes encoding enzymes involved in estrogen metabolism may modulate the risk of prostate cancer in populations of African ancestry. PMID:27074016

The association between well-being and the COMT gene: Dispositional gratitude and forgiveness as mediators.

PubMed

Liu, Jinting; Gong, Pingyuan; Gao, Xiaoxue; Zhou, Xiaolin

2017-05-01

Previous studies have demonstrated the contributions of genetic variants and positive psychological traits (e.g. gratitude and forgiveness) to well-being. However, little is known about how genes interact with positive traits to affect well-being. To investigate to what extent the COMT Val158Met polymorphism modulates well-being and to what extent dispositional gratitude and forgiveness mediate the individual differences in well-being, 445 participants were recruited and required to complete a battery of questionnaires. We found that individuals with a smaller number of the Met alleles reported greater well-being, less depressive symptoms, and greater tendencies for gratitude and forgiveness. Moreover, dispositional gratitude and forgiveness mediated the genotype effects on well-being and depressive symptoms. These results remained significant after controlling for non-genetic factors (socioeconomic status, religious beliefs, romantic relationship status, parenting style). The sample size limits the generalizability of results. This study demonstrates the contribution of the COMT Val158Met polymorphism to individual differences in well-being and suggests a potential psychobiological pathway from dopaminergic and noradrenergic systems to happiness. Copyright © 2017 Elsevier B.V. All rights reserved.

Paranormal experience and the COMT dopaminergic gene: a preliminary attempt to associate phenotype with genotype using an underlying brain theory.

PubMed

Raz, Amir; Hines, Terence; Fossella, John; Castro, Daniella

2008-01-01

Paranormal belief and suggestibility seem related. Given our recent findings outlining a putative association between suggestibility and a specific dopaminergic genetic polymorphism, we hypothesized that similar exploratory genetic data may offer supplementary insights into a similar correlation with paranormal belief. With more affordable costs and better technology in the aftermath of the human genome project, genotyping is increasingly ubiquitous. Compelling brain theories guide specific research hypotheses as scientists begin to unravel tentative relationships between phenotype and genotype. In line with a dopaminergic brain theory, we tried to correlate a specific phenotype concerning paranormal belief with a dopaminergic gene (COMT) known for its involvement in prefrontal executive cognition and for a polymorphism that is positively correlated with suggestibility. Although our preliminary findings are inconclusive, the research approach we outline should pave the road to a more scientific account of elucidating paranormal belief.

Variability in Estrogen-Metabolizing Genes and Their Association with Genomic Instability in Untreated Breast Cancer Patients and Healthy Women

PubMed Central

Alves dos Santos, Raquel; Teixeira, Ana Cláudia; Mayorano, Mônica Beatriz; Carrara, Hélio Humberto Angotti; Moreira de Andrade, Jurandyr; Takahashi, Catarina Satie

2011-01-01

In the present study, we investigated the relationship between polymorphisms in the estrogen-metabolizing genes CYP17, CYP1B1, CYP1A1, and COMT and genomic instability in the peripheral blood lymphocytes of 62 BC patients and 62 controls considering that increased or prolonged exposure to estrogen can damage the DNA molecule and increase the genomic instability process in breast tissue. Our data demonstrated increased genomic instability in BC patients and that individuals with higher frequencies of MN exhibited higher risk to BC when belonging Val/Met genotype of the COMT gene. We also observed that CYP17 and CYP1A1 polymorphisms can modify the risk to BC depending on the menopause status. We can conclude that the genetic background in estrogen metabolism pathway can modulate chromosome damage in healthy controls and patients and thereby influence the risk to BC. These findings suggest the importance to ally biomarkers of susceptibility and effects to estimate risk groups. PMID:21716904

Nonlinear modulation of interacting between COMT and depression on brain function.

PubMed

Gong, L; He, C; Yin, Y; Ye, Q; Bai, F; Yuan, Y; Zhang, H; Lv, L; Zhang, H; Zhang, Z; Xie, C

2017-09-01

The catechol-O-methyltransferase (COMT) gene is related to dopamine degradation and has been suggested to be involved in the pathogenesis of major depressive disorder (MDD). However, how this gene affects brain function properties in MDD is still unclear. Fifty patients with MDD and 35 cognitively normal participants underwent a resting-state functional magnetic resonance imaging scan. A voxelwise and data-drive global functional connectivity density (gFCD) analysis was used to investigate the main effects and the interactions of disease states and COMT rs4680 gene polymorphism on brain function. We found significant group differences of the gFCD in bilateral fusiform area (FFA), post-central and pre-central cortex, left superior temporal gyrus (STG), rectal and superior temporal gyrus and right ventrolateral prefrontal cortex (vlPFC); abnormal gFCDs in left STG were positively correlated with severity of depression in MDD group. Significant disease×COMT interaction effects were found in the bilateral calcarine gyrus, right vlPFC, hippocampus and thalamus, and left SFG and FFA. Further post-hoc tests showed a nonlinear modulation effect of COMT on gFCD in the development of MDD. Interestingly, an inverted U-shaped modulation was found in the prefrontal cortex (control system) but U-shaped modulations were found in the hippocampus, thalamus and occipital cortex (processing system). Our study demonstrated nonlinear modulation of the interaction between COMT and depression on brain function. These findings expand our understanding of the COMT effect underlying the pathophysiology of MDD. Copyright © 2017 Elsevier Masson SAS. All rights reserved.

Gender effects of the COMT Val 158 Met genotype on verbal fluency in healthy adults.

PubMed

Soeiro-De-Souza, Marcio Gerhardt; Bio, Danielle Soares; David, Denise Petresco; Missio, Giovani; Lima, Bruno; Fernandes, Fernando; Machado-Vieira, Rodrigo; Moreno, Ricardo Alberto

2013-09-01

Cognitive performance in healthy individuals is associated with gender differences in specific tests; a female advantage has been demonstrated in language tests, whereas a male advantage has been demonstrated in spatial relation examinations. The prefrontal cortex (PFC) mediates important cognitive domains and is influenced by dopamine (DA) activity. The single nucleotide polymorphism (SNP) rs4680 in the catechol‑O‑methyltransferase (COMT) gene results in an amino acid substitution from valine (Val) to methionine (Met). The Met allele has been demonstrated to decrease COMT enzyme activity and improve PFC cognitive function. COMT regulates DA activity in the PFC and exhibits gender effects. The aim of the present study was to investigate the gender‑specific effects of the COMT genotype on cognition in healthy young adults. Seventy‑six healthy subjects were genotyped for COMT rs4680 and submitted to an extensive range of neuropsychological tests assessing aspects of PFC function. The COMT Met allele influenced the performance of executive function. The results revealed gender effects of the COMT rs4680 Met allele on verbal fluency, with positive effects in males and negative effects in females. This suggested that DA activity affects cognitive function in different ways, according to gender.

The association between COMT Val158Met polymorphism and migraine risk: A meta-analysis.

PubMed

Liao, Yao-Jun; Jiang, Jing-Ru; Jin, San-Qing

2017-05-01

Background The COMT Val158Met polymorphism has long been regarded as a risk factor for migraine. The possible association between COMT Val158Met polymorphism and migraine has been evaluated in several studies, but the results are not consistent. Therefore, we conduct this meta-analysis to address these issues. Methods The WEB OF SCIENCE and EMBASE databases were searched for eligible studies. The odds ratio (OR) with the corresponding 95% confidence interval (CI) was calculated to estimate the strength of the association between COMT Val158Met polymorphism and migraine. Results Five studies with 979 cases and 1870 controls were ultimately included in the present meta-analysis. The overall data showed no significant association between COMT Val158Met polymorphism and migraine in the multiplicative model (OR = 0.97, 95% CI: 0.78-1.21, p = 0.805) and dominant model (OR = 1.05, 95% CI: 0.75-1.48, p = 0.773), neither in the additive model (OR = 0.97, 95% CI: 0.77-1.23, p = 0.817) nor in the recessive model (OR = 0.88, 95% CI: 0.71-1.09, p = 0.246). In subgroup analysis, both for Caucasian and Asian populations, no statistically significant associations were observed in any genetic models. Conclusions Our meta-analysis suggested that the COMT Val158Met polymorphism was not associated with migraine risk.

The COMT Val/Met polymorphism is associated with reading-related skills and consistent patterns of functional neural activation.

PubMed

Landi, Nicole; Frost, Stephen J; Mencl, W Einar; Preston, Jonathan L; Jacobsen, Leslie K; Lee, Maria; Yrigollen, Carolyn; Pugh, Kenneth R; Grigorenko, Elena L

2013-01-01

In both children and adults there is large variability in reading skill, with approximately 5-10% of individuals characterized as having reading disability; these individuals struggle to learn to read despite adequate intelligence and opportunity. Although it is well established that a substantial portion of this variability is attributed to the genetic differences between individuals, specifics of the connections between reading and the genome are not understood. This article presents data that suggest that variation in the COMT gene, which has previously been associated with variation in higher-order cognition, is associated with reading and reading-related skills, at the level of both brain and behavior. In particular, we found that the COMT Val/Met polymorphism at rs4680, which results in the substitution of the ancestral Valine (Val) by Methionine (Met), was associated with better performance on a number of critical reading measures and with patterns of functional neural activation that have been linked to better readers. We argue that this polymorphism, known for its broad effects on cognition, may modulate (likely through frontal lobe function) reading skill. © 2012 Blackwell Publishing Ltd.

The COMT Val/Met polymorphism is associated with reading related skills and consistent patterns of functional neural activation

PubMed Central

Landi, Nicole; Frost, Stephen J.; Mencl, W. Einar; Preston, Jonathan L.; Jacobsen, Leslie K.; Lee, Maria; Yrigollen, Carolyn; Pugh, Kenneth R.; Grigorenko, Elena L.

2013-01-01

In both children and adults there is large variability in reading skill, with approximately 5–10% of individuals characterized as having reading disability; these individuals struggle to learn to read despite adequate intelligence and opportunity. Although it is well established that a substantial portion of this variability is attributed to the genetic differences between individuals, specifics of the connections between reading and the genome are not understood. This article presents data that suggest that variation in the COMT gene, which has previously been associated with variation in higher-order cognition, is associated with reading and reading-related skills, both at the level of brain and behavior. In particular, we found that the COMT Val/Met polymorphism at rs4680, which results in the substitution of the ancestral Valine (Val) by Methionine (Met), was associated with better performance on a number of critical reading measures and with patterns of functional neural activation that have been linked to better readers. We argue that this polymorphism, known for its broad effects on cognition, may modulate (likely through frontal lobe function) reading skill. PMID:23278923

Pain modality- and sex-specific effects of COMT genetic functional variants

PubMed Central

Belfer, Inna; Segall, Samantha K.; Lariviere, William R.; Smith, Shad B.; Dai, Feng; Slade, Gary G.; Rashid, Naim U.; Mogil, Jeffrey S.; Campbell, Claudia; Edwards, Robert; Liu, Qian; Bair, Eric; Maixner, William; Diatchenko, Luda

2013-01-01

The enzyme catechol-O-methyltransferase (COMT) metabolizes catecholamine neurotransmitters involved in a number of physiological functions including pain perception. Both human and mouse COMT genes possess functional polymorphisms contributing to inter-individual variability in pain phenotypes such as sensitivity to noxious stimuli, severity of clinical pain and response to pain treatment. In this study, we found that the effects of Comt functional variation in mice are modality-specific. Spontaneous inflammatory nociception and thermal nociception behaviors were correlated the most with the presence of the B2 SINE transposon insertion residing in the 3’UTR mRNA region. Similarly, in humans, COMT functional haplotypes were associated with thermal pain perception and with capsaicin-induced pain. Furthermore, COMT genetic variations contributed to pain behaviors in mice and pain ratings in humans in a sex-specific manner. The ancestral Comt variant, without a B2 SINE insertion, was more strongly associated with sensitivity to capsaicin in female versus male mice. In humans, the haplotype coding for low COMT activity increased capsaicin-induced pain perception in women, but not men. These findings reemphasize the fundamental contribution of COMT to pain processes, and provide a fine-grained resolution of this contribution at the genetic level that can be used to guide future studies in the area of pain genetics. PMID:23701723

Association of COMT and PRODH gene variants with intelligence quotient (IQ) and executive functions in 22q11.2DS subjects.

PubMed

Carmel, Miri; Zarchi, Omer; Michaelovsky, Elena; Frisch, Amos; Patya, Miriam; Green, Tamar; Gothelf, Doron; Weizman, Abraham

2014-09-01

The 22q11.2 deletion syndrome (22q11.2DS) carries the highest genetic risk factor for the development of schizophrenia. We investigated the association of genetic variants in two schizophrenia candidate genes with executive function (EF) and IQ in 22q11.2DS individuals. Ninety two individuals with 22q11.2 deletion were studied for the genetic association between COMT and PRODH variants and EF and IQ. Subjects were divided into children (under 12 years old), adolescents (between 12 and 18 years old) and adults (older than 18 years), and genotyped for the COMT Val158Met (rs4680) and PRODH Arg185Trp (rs4819756) polymorphisms. The participants underwent psychiatric evaluation and EF assessment. Our main finding is a significant influence of the COMT Val158Met polymorphism on both IQ and EF performance. Specifically, 22q11.2DS subjects with Met allele displayed higher IQ scores in all age groups compared to Val carriers, reaching significance in both adolescents and adults. The Met allele carriers performed better than Val carriers in EF tasks, being statistically significant in the adult group. PRODH Arg185Trp variant did not affect IQ or EF in our 22q11.2DS cohort. In conclusion, functional COMT variant, but not PRODH, affects IQ and EF in 22q11.2DS subjects during neurodevelopment with a maximal effect at adulthood. Future studies should monitor the cognitive performance of the same individuals from childhood to old age. Copyright © 2014 Elsevier Ltd. All rights reserved.

Genotype distribution of estrogen receptor-alpha, catechol-O-methyltransferase, and cytochrome P450 17 gene polymorphisms in Caucasian women with uterine leiomyomas.

PubMed

Denschlag, Dominik; Bentz, Eva-Katrin; Hefler, Lukas; Pietrowski, Detlef; Zeillinger, Robert; Tempfer, Clemens; Tong, Dan

2006-02-01

To evaluate the association between the presence of uterine leiomyomas and three functional single nucleotide polymorphisms (SNPs) of the estrogen receptor alpha (ESR1), catechol-O-methyltransferase (COMT), and cytochrom P450 17 (CYP17A) genes, which have been described to modify the estrogen metabolism. Prospective case control study. Academic research institution. One hundred thirty women with clinically and surgically diagnosed uterine leiomyomas and 139 population controls. Peripheral venous puncture. Polymerase chain reaction and pyrosequencing were performed to genotype women with respect to the ESR1 IVS1-397 T/C (PvuII), COMT G158A, and the CYP17A 34T-->C SNPs. Comparing women with uterine leiomyomas and controls, no statistically significant differences with respect to allele frequency and genotype distribution were ascertained for ESR1 IVS 1-397 T/C (PvuII) (P=0.9 and P=0.6, respectively), COMT G158A (P=0.3 and P=0.6, respectively), and CYP17A 34T-->C (P=0.1 and P=0.5, respectively). When all two-way interactions of investigated SNPs were ascertained, no significant interactions were observed. In a multivariate model, no SNP was significantly associated with leiomyomas. Carriage of the ESR1 IVS1-397 T/C (PvuII), COMT G158A, and the CYP17A 34T-->C SNPs is not associated with the susceptibility to uterine leiomyoma in a Caucasian population.

Catechol-O-methyltransferase gene variants may associate with negative symptom response and plasma concentrations of prolactin in schizophrenia after amisulpride treatment.

PubMed

Chen, Chun-Yen; Yeh, Yi-Wei; Kuo, Shin-Chang; Ho, Pei-Shen; Liang, Chih-Sung; Yen, Che-Hung; Lu, Ru-Band; Huang, San-Yuan

2016-03-01

Catechol-O-methyltransferase (COMT) enzyme is involved in the pathogenesis of psychotic symptoms and may be associated with a therapeutic response to antipsychotic drugs. The aim of this study was to examine the relationship between COMT variants, plasma prolactin level, and the therapeutic effectiveness of amisulpride treatment in patients with schizophrenia. A 12-week naturalistic study of amisulpride treatment was carried out in 185 Han Chinese patients with schizophrenia. The patients were screened for 14 single-nucleotide polymorphisms of the COMT gene. The Positive and Negative Syndrome Scale (PANSS) was used to assess the improvement of psychopathological symptoms from the baseline to the end point in each subject. For better presentation of time-course changes in response status, a mixed model for repeated-measures (MMRM) analysis of symptom improvement during the 12-week treatment period was conducted. The change in plasma prolactin level after amisulpride treatment was also examined (n=51). No significant differences in the genotype frequencies of the COMT variants investigated were observed between responders and non-responders. Moreover, an MMRM analysis of psychopathological symptom improvement during the 12-week treatment course showed that it depended significantly on COMT variants (rs4680, rs4633, and rs6267), particularly regarding changes in negative symptoms. The increase in plasma prolactin levels observed was influenced by the COMT rs4680 variant and was positively correlated with a reduction in PANSS negative scores. Our results suggest that variation of the COMT gene is associated with treatment response regarding negative symptoms and prolactin changes after amisulpride treatment in patients with schizophrenia. Copyright © 2015 Elsevier Ltd. All rights reserved.

Moderation of the effect of adolescent-onset cannabis use on adult psychosis by a functional polymorphism in the catechol-O-methyltransferase gene: longitudinal evidence of a gene X environment interaction.

PubMed

Caspi, Avshalom; Moffitt, Terrie E; Cannon, Mary; McClay, Joseph; Murray, Robin; Harrington, HonaLee; Taylor, Alan; Arseneault, Louise; Williams, Ben; Braithwaite, Antony; Poulton, Richie; Craig, Ian W

2005-05-15

Recent evidence documents that cannabis use by young people is a modest statistical risk factor for psychotic symptoms in adulthood, such as hallucinations and delusions, as well as clinically significant schizophrenia. The vast majority of cannabis users do not develop psychosis, however, prompting us to hypothesize that some people are genetically vulnerable to the deleterious effects of cannabis. In a longitudinal study of a representative birth cohort followed to adulthood, we tested why cannabis use is associated with the emergence of psychosis in a minority of users, but not in others. A functional polymorphism in the catechol-O-methyltransferase (COMT) gene moderated the influence of adolescent cannabis use on developing adult psychosis. Carriers of the COMT valine158 allele were most likely to exhibit psychotic symptoms and to develop schizophreniform disorder if they used cannabis. Cannabis use had no such adverse influence on individuals with two copies of the methionine allele. These findings provide evidence of a gene x environment interaction and suggest that a role of some susceptibility genes is to influence vulnerability to environmental pathogens.

COMT val108/158 met genotype affects neural but not cognitive processing in healthy individuals.

PubMed

Dennis, Nancy A; Need, Anna C; LaBar, Kevin S; Waters-Metenier, Sheena; Cirulli, Elizabeth T; Kragel, James; Goldstein, David B; Cabeza, Roberto

2010-03-01

The relationship between cognition and a functional polymorphism in the catechol-O-methlytransferase (COMT) gene, val108/158met, is one of debate in the literature. Furthermore, based on the dopaminergic differences associated with the COMT val108/158met genotype, neural differences during cognition may be present, regardless of genotypic differences in cognitive performance. To investigate these issues the current study aimed to 1) examine the effects of COMT genotype using a large sample of healthy individuals (n = 496-1218) and multiple cognitive measures, and using a subset of the sample (n = 22), 2) examine whether COMT genotype effects medial temporal lobe (MTL) and frontal activity during successful relational memory processing, and 3) investigate group differences in functional connectivity associated with successful relational memory processing. Results revealed no significant group difference in cognitive performance between COMT genotypes in any of the 19 cognitive measures. However, in the subset sample, COMT val homozygotes exhibited significantly decreased MTL and increased prefrontal activity during both successful relational encoding and retrieval, and reduced connectivity between these regions compared with met homozygotes. Taken together, the results suggest that although the COMT val108/158met genotype has no effect on cognitive behavioral measures in healthy individuals, it is associated with differences in neural process underlying cognitive output.

Influence of BDNF and COMT polymorphisms on emotional decision making.

PubMed

Kang, Jee In; Namkoong, Kee; Ha, Ra Yeon; Jhung, Kyungun; Kim, Yang Tae; Kim, Se Joo

2010-06-01

Decision making is an important brain function. Although little is known about the genetic basis of decision making, it has been suggested that it is mediated by the modulation of neurotransmitter systems. We investigated how the BDNF Val66Met and COMT Val158Met polymorphisms affect emotional decision making using the Iowa Gambling Task (IGT). One hundred sixty-eight healthy Korean college students (93 males, 75 females) with a complete dataset were included in the data analysis. The IGT and genotyping for the polymorphisms of BDNF Val66Met and COMT Val158Met were performed. Both Met/Met and Val/Met of the BDNF Val66Met polymorphism were significantly associated with a lower mean score of blocks 3-5 of the IGT and with less improvement from block 1 to block 3-5 than the Val/Val. However, the BDNF was not significantly associated with the score of block 1, and the COMT Val158Met polymorphism produced no significant effect on IGT performance. No interaction effect was observed between the BDNF and the COMT for the IGT. These findings suggest the BDNF Val66Met may affect the emotional decision making performance. (c) 2010 Elsevier Ltd. All rights reserved.

Candidate genes for alcohol dependence: A genetic association study from India.

PubMed

Malhotra, Savita; Basu, Debasish; Khullar, Madhu; Ghosh, Abhishek; Chugh, Neera

2016-11-01

Search for candidate genes for alcohol dependence (AD) has been inconsistent and inconclusive. Moreover, most of the research has been confined to a few specific ethnic groups. Hence, the aim of our study was to explore specific candidate genes for AD in north Indian male population. In this clinic-based genetic association study, 210 males with AD and 200 controls matched for age, gender and ethnicity were recruited from the clinic and the general population, respectively. Cases were diagnosed with Semi-structured Assessment for Genetics of Alcoholism-II (SSAGA-II). Single-nucleotide polymorphism genotyping was done by real-time quantitative-polymerase chain reaction (PCR) using Taq Man assay (ABI 7500) fast real-time PCR system. Both at the genotypic level and at allelic frequency, Met158 variant of catechol-O-methyl transferase (COMT) showed significant increase in cases as compared to controls. The frequency of heterozygous genotype (A/G) of gamma-aminobutyric acid receptor A1 (GABRA1) was significantly lower in cases as compared to controls. Likewise, for GABRA2, the frequency of homozygous recessive genotype (G/G) was significantly higher in the control group. With respect to the 5-hydroxytryptamine (5HT) transporter long promoter region (5HTTLPR), cholinergic receptor muscarinic (CHRM2) and alcohol dehydrogenase 1B (ADH1B) genes, there was no significant difference between the cases and the controls. Aldehyde dehydrogenase (ALDH2) gene was found to be monomorphic in our study population. Our study findings showed COMT polymorphism conferring risk and GABRA polymorphism as a protective genotype for Indian male with AD. Genes for alcohol metabolism, serotonin transporter and cholinergic receptor gene polymorphism were perhaps not contributory to AD for Indian population.

Count on dopamine: influences of COMT polymorphisms on numerical cognition

PubMed Central

Júlio-Costa, Annelise; Antunes, Andressa M.; Lopes-Silva, Júlia B.; Moreira, Bárbara C.; Vianna, Gabrielle S.; Wood, Guilherme; Carvalho, Maria R. S.; Haase, Vitor G.

2013-01-01

Catechol-O-methyltransferase (COMT) is an enzyme that is particularly important for the metabolism of dopamine. Functional polymorphisms of COMT have been implicated in working memory and numerical cognition. This is an exploratory study that aims at investigating associations between COMT polymorphisms, working memory, and numerical cognition. Elementary school children from 2th to 6th grades were divided into two groups according to their COMT val158met polymorphism [homozygous for valine allele (n = 61) vs. heterozygous plus methionine homozygous children or met+ group (n = 94)]. Both groups were matched for age and intelligence. Working memory was assessed through digit span and Corsi blocks. Symbolic numerical processing was assessed through transcoding and single-digit word problem tasks. Non-symbolic magnitude comparison and estimation tasks were used to assess number sense. Between-group differences were found in symbolic and non-symbolic numerical tasks, but not in working memory tasks. Children in the met+ group showed better performance in all numerical tasks while val homozygous children presented slower development of non-symbolic magnitude representations. These results suggest COMT-related dopaminergic modulation may be related not only to working memory, as found in previous studies, but also to the development of magnitude processing and magnitude representations. PMID:23966969

Regional Anesthesia and Valproate Sodium for the Prevention of Chronic Post-Amputation Pain

DTIC Science & Technology

2013-10-01

revised documents August Non-perishable Supplies ordered & received DUKE IRB approved study via expedited review September Submitted all revisions...2013 February March April May June July August September October HRPO request for revised, addtn’l docs VA approved protocol...A few candidate gene polymorphisms have been linked to pain susceptibility, including catechol-O-methyltranferase ( COMT ). This gene modulates

COMT Val(158)Met genotype and cannabis use in people with an At Risk Mental State for psychosis: Exploring Gene x Environment interactions.

PubMed

Nieman, Dorien H; Dragt, Sara; van Duin, Esther D A; Denneman, Nadine; Overbeek, Jozefien M; de Haan, Lieuwe; Rietdijk, Judith; Ising, Helga K; Klaassen, Rianne M C; van Amelsvoort, Thérèse; Wunderink, Lex; van der Gaag, Mark; Linszen, Don H

2016-07-01

Epidemiological and retrospective studies suggest a cannabis x catechol-O-methyltransferase (COMT) Val(158)Met interaction effect on development of psychosis. The aim of this study was to examine this interaction and its association with severity of subclinical symptoms in people with an At Risk Mental State (ARMS) for psychosis. Severity of symptoms, cannabis use and genotype were assessed at baseline in 147 help-seeking young adults who met the ARMS criteria and agreed to participate in the Dutch Early Detection and Intervention (EDIE-NL) trial. Cannabis use and COMT Val-allele showed an interaction effect in ARMS subjects. Subjects who were weekly cannabis users at some point prior to entering the study showed more severe positive symptoms. This effect increased if they were carriers of the COMT Val-allele and even more so if they were homozygous for the Val-allele. Our results suggest that the COMT Val(158)Met polymorphism moderates the effect of regular cannabis use on severity of subclinical psychotic symptoms. Copyright © 2016 Elsevier B.V. All rights reserved.

No association between catechol-O-methyltransferase (COMT) genotype and attention deficit hyperactivity disorder (ADHD) in Japanese children.

PubMed

Yatsuga, Chiho; Toyohisa, Daiki; Fujisawa, Takashi X; Nishitani, Shota; Shinohara, Kazuyuki; Matsuura, Naomi; Ikeda, Shinobu; Muramatsu, Masaaki; Hamada, Akinobu; Tomoda, Akemi

2014-08-01

This study ascertained the association between attention deficit/hyperactivity disorder (ADHD) in Japanese children and a polymorphism of catechol-O-methyltransferase (COMT), a dopamine-control gene. The secondary aim of the study was the evaluation of a putative association between methylphenidate (MPH) effect/adverse effects and the COMT genotype. To ascertain the distribution of the Val158Met variant of COMT, 50 children meeting ADHD inclusion criteria were compared with 32 healthy children. Clinical improvement and the occurrence of adverse effects were measured before and 3 months after MPH administration in children with ADHD, and analyzed for genotype association. Wechsler Intelligence Scale for Children-Third Edition (WISC-III), age, MPH dose were included as co-variables. The occurrence of the COMT Val/Val genotype was significantly higher in children with ADHD (χ(2)(1)=7.13, p<0.01). However, there was no significant difference in the Val/Val genotype according to disorder, and WISC and ADHD rating scale scores, after correcting for the interaction between disorder and COMT genotype. Furthermore, no significant difference in MPH effect/adverse effects was observed in association with the COMT genotype in the ADHD group. These results showed a lack of association between the COMT Val/Val genotype and ADHD in Japan. Copyright © 2013 The Japanese Society of Child Neurology. Published by Elsevier B.V. All rights reserved.

The Influence of Genetic and Environmental Factors among MDMA Users in Cognitive Performance

PubMed Central

Cuyàs, Elisabet; Verdejo-García, Antonio; Fagundo, Ana Beatriz; Khymenets, Olha; Rodríguez, Joan; Cuenca, Aida; de Sola Llopis, Susana; Langohr, Klaus; Peña-Casanova, Jordi; Torrens, Marta; Martín-Santos, Rocío; Farré, Magí; de la Torre, Rafael

2011-01-01

This study is aimed to clarify the association between MDMA cumulative use and cognitive dysfunction, and the potential role of candidate genetic polymorphisms in explaining individual differences in the cognitive effects of MDMA. Gene polymorphisms related to reduced serotonin function, poor competency of executive control and memory consolidation systems, and high enzymatic activity linked to bioactivation of MDMA to neurotoxic metabolites may contribute to explain variations in the cognitive impact of MDMA across regular users of this drug. Sixty ecstasy polydrug users, 110 cannabis users and 93 non-drug users were assessed using cognitive measures of Verbal Memory (California Verbal Learning Test, CVLT), Visual Memory (Rey-Osterrieth Complex Figure Test, ROCFT), Semantic Fluency, and Perceptual Attention (Symbol Digit Modalities Test, SDMT). Participants were also genotyped for polymorphisms within the 5HTT, 5HTR2A, COMT, CYP2D6, BDNF, and GRIN2B genes using polymerase chain reaction and TaqMan polymerase assays. Lifetime cumulative MDMA use was significantly associated with poorer performance on visuospatial memory and perceptual attention. Heavy MDMA users (>100 tablets lifetime use) interacted with candidate gene polymorphisms in explaining individual differences in cognitive performance between MDMA users and controls. MDMA users carrying COMT val/val and SERT s/s had poorer performance than paired controls on visuospatial attention and memory, and MDMA users with CYP2D6 ultra-rapid metabolizers performed worse than controls on semantic fluency. Both MDMA lifetime use and gene-related individual differences influence cognitive dysfunction in ecstasy users. PMID:22110616

COMT Val158Met and 5-HT1A-R -1019 C/G polymorphisms: effects on the negative symptom response to clozapine.

PubMed

Bosia, Marta; Lorenzi, Cristina; Pirovano, Adele; Guglielmino, Carmelo; Cocchi, Federica; Spangaro, Marco; Bramanti, Placido; Smeraldi, Enrico; Cavallaro, Roberto

2015-01-01

Clozapine is still considered the gold standard for treatment-resistant schizophrenia patients; however, up to 40% of patients do not respond adequately. Identifying potential predictors of clinical response to this last-line antipsychotic could represent an important goal for treatment. Among these, functional polymorphisms involved in dopamine system modulation, known to be disrupted in schizophrenia, may play a role. We examined the COMT Val158Met polymorphism, which plays a key role in dopamine regulation at the prefrontal level, and the 5-HT1A-R -1019 C/G polymorphism, a target of clozapine activity involved in the interaction between the serotonin and dopamine systems. 107 neuroleptic-refractory, biologically unrelated Italian patients (70 males and 37 females) with a DSM-IV diagnosis of schizophrenia who were being treated with clozapine were recruited. Psychopathology was assessed by the Positive and Negative Symptoms Scale (PANSS) at the beginning of treatment, and at weeks 8 and 12. Genomic DNA was extracted from venous blood samples. COMT rs4680 (Val158Met) and 5-HT1A-R rs6295 (-1019 C/G) polymorphisms were analyzed by PCR-based restriction fragment length and direct sequencing, respectively. We found a significant effect of COMT and 5-HT1A-R on the PANSS Negative Subscale variation, with greater improvement among COMT Val/Val and 5-HT1A-R G/G subjects. The findings support the hypothesis that COMT rs4680 and 5-HT1A-R rs6295 polymorphisms could influence the negative symptom response to clozapine, probably through modulation of the dopaminergic system.

Stress-induced analgesia and morphine responses are changed in catechol-O-methyltransferase-deficient male mice.

PubMed

Kambur, Oleg; Männistö, Pekka T; Viljakka, Kaarin; Reenilä, Ilkka; Lemberg, Kim; Kontinen, Vesa K; Karayiorgou, Maria; Gogos, Joseph A; Kalso, Eija

2008-10-01

Catechol-O-methyltransferase (COMT) polymorphisms modulate pain and opioid analgesia in human beings. It is not clear how the effects of COMT are mediated and only few relevant animal studies have been performed. Here, we used old male Comt gene knock-out mice as an animal model to study the effects of COMT deficiency on nociception that was assessed by the hot plate and tail flick tests. Stress-induced analgesia was achieved by forced swim. Morphine antinociception was measured after 10 mg/kg of morphine subcutaneously. Morphine tolerance was produced with subcutaneous morphine pellets and withdrawal provoked with subcutaneous naloxone. In the hot plate test, morphine-induced antinociception was significantly greater in the COMT knock-out mice, compared to the wild-type mice. This may be due to increased availability of opioid receptors as suggested by previous human studies. In the tail flick test, opioid-mediated stress-induced analgesia was absent and morphine-induced analgesia was decreased in COMT knock-out mice. In the hot plate test, stress-induced analgesia developed to all mice regardless of the COMT genotype. There were no differences between the genotypes in the baseline nociceptive thresholds, morphine tolerance and withdrawal. Our findings show, for the first time, the importance of COMT activity in stress- and morphine-induced analgesia in mice. COMT activity seems to take part in the modulation of nociception not only in the brain, as suggested earlier, but also at the spinal/peripheral level.

Genetic Variation in COMT Activity Impacts Learning and Dopamine Release Capacity in the Striatum

ERIC Educational Resources Information Center

Simpson, Eleanor H.; Morud, Julia; Winiger, Vanessa; Biezonski, Dominik; Zhu, Judy P.; Bach, Mary Elizabeth; Malleret, Gael; Polan, H. Jonathan; Ng-Evans, Scott; Phillips, Paul E. M.; Kellendonk, Christoph; Krandel, Eric R.

2014-01-01

A common genetic polymorphism that results in increased activity of the dopamine regulating enzyme COMT (the "COMT Val" [superscript 158] allele) has been found to associate with poorer cognitive performance and increased susceptibility to develop psychiatric disorders. It is generally assumed that this increase in COMT activity…

Polymorphisms in phase I and phase II genes and breast cancer risk and relations to persistent organic pollutant exposure: a case-control study in Inuit women.

PubMed

Ghisari, Mandana; Eiberg, Hans; Long, Manhai; Bonefeld-Jørgensen, Eva C

2014-03-16

We have previously reported that chemicals belonging to the persistent organic pollutants (POPs) such as perfluorinated compounds (PFAS) and polychlorinated biphenyls (PCBs) are risk factors in Breast Cancer (BC) development in Greenlandic Inuit women. The present case-control study aimed to investigate the main effect of polymorphisms in genes involved in xenobiotic metabolism and estrogen biosynthesis, CYP1A1, CYP1B1, COMT and CYP17, CYP19 and the BRCA1 founder mutation in relation to BC risk and to explore possible interactions between the gene polymorphisms and serum POP levels on BC risk in Greenlandic Inuit women. The study population consisted of 31 BC cases and 115 matched controls, with information on serum levels of POPs. Genotyping was conducted for CYP1A1 (Ile462Val; rs1048943), CYP1B1 (Leu432Val; rs1056836), COMT (Val158Met; rs4680), CYP17A1 (A1> A2; rs743572); CYP19A1 (C> T; rs10046) and CYP19A1 ((TTTA)n repeats) polymorphisms and BRCA1 founder mutation using TaqMan allelic discrimination method and polymerase chain reaction based restriction fragment length polymorphism. The χ2 -test was used to compare categorical variables between cases and controls and the odds ratios were estimated by unconditional logistic regression models. We found an independent association of CYP1A1 (Val) and CYP17 (A1) with BC risk.Furthermore, an increased BC risk was observed for women with high serum levels of perfluorooctane sulfonate (PFOS) and perfluorooctanoic acid (PFOA) and carriers of at least: one CYP1A1 variant Val allele; one variant COMT Met allele; or the common CYP17 A1 allele. No combined effects were seen between PFAS exposure and CYP1B1 and CYP19 polymorphisms. The risk of BC was not found significantly associated with exposure to PCBs and OCPs, regardless of genotype for all investigated SNPs. The frequency of the Greenlandic founder mutation in BRCA1 was as expected higher in cases than in controls. The BRCA1 founder mutation and polymorphisms in CYP1A1 (Val) and CYP17 (A1) can increase the BC risk among Inuit women and the risk increases with higher serum levels of PFOS and PFOA. Serum PFAS levels were a consistent risk factor of BC, but inter-individual polymorphic differences might cause variations in sensitivity to the PFAS/POP exposure.

Association of COMT (Val158Met) and BDNF (Val66Met) Gene Polymorphisms with Anxiety, ADHD and Tics in Children with Autism Spectrum Disorder

PubMed Central

Gadow, Kenneth D.; Roohi, Jasmin; DeVincent, Carla J.; Kirsch, Sarah; Hatchwell, Eli

2015-01-01

The aim of the study is to examine rs4680 (COMT) and rs6265 (BDNF) as genetic markers of anxiety, ADHD, and tics. Parents and teachers completed a DSM-IV-referenced rating scale for a total sample of 67 children with autism spectrum disorder (ASD). Both COMT (p = 0.06) and BDNF (p = 0.07) genotypes were marginally significant for teacher ratings of social phobia (ηp2 = 0.06). Analyses also indicated associations of BDNF genotype with parent-rated ADHD (p = 0.01, ηp2 = 0.10) and teacher-rated tics (p = 0.04; ηp2 = 0.07). There was also evidence of a possible interaction (p = 0.02, ηp2 = 0.09) of BDNF genotype with DAT1 3′ VNTR with tic severity. BDNF and COMT may be biomarkers for phenotypic variation in ASD, but these preliminary findings remain tentative pending replication with larger, independent samples. PMID:19582565

Association of COMT (Val158Met) and BDNF (Val66Met) gene polymorphisms with anxiety, ADHD and tics in children with autism spectrum disorder.

PubMed

Gadow, Kenneth D; Roohi, Jasmin; DeVincent, Carla J; Kirsch, Sarah; Hatchwell, Eli

2009-11-01

The aim of the study is to examine rs4680 (COMT) and rs6265 (BDNF) as genetic markers of anxiety, ADHD, and tics. Parents and teachers completed a DSM-IV-referenced rating scale for a total sample of 67 children with autism spectrum disorder (ASD). Both COMT (p = 0.06) and BDNF (p = 0.07) genotypes were marginally significant for teacher ratings of social phobia (etap (2) = 0.06). Analyses also indicated associations of BDNF genotype with parent-rated ADHD (p = 0.01, etap (2) = 0.10) and teacher-rated tics (p = 0.04; etap (2) = 0.07). There was also evidence of a possible interaction (p = 0.02, etap (2) = 0.09) of BDNF genotype with DAT1 3' VNTR with tic severity. BDNF and COMT may be biomarkers for phenotypic variation in ASD, but these preliminary findings remain tentative pending replication with larger, independent samples.

COMT ValMet moderation of cannabis-induced psychosis: a momentary assessment study of 'switching on' hallucinations in the flow of daily life.

PubMed

Henquet, C; Rosa, A; Delespaul, P; Papiol, S; Fananás, L; van Os, J; Myin-Germeys, I

2009-02-01

A functional polymorphism in the catechol-o-methyltransferase gene (COMT Val(158)Met) may moderate the psychosis-inducing effects of cannabis. In order to extend this finding to dynamic effects in the flow of daily life, a momentary assessment study of psychotic symptoms in response to cannabis use was conducted. The experience sampling technique was used to collect data on cannabis use and occurrence of symptoms in daily life in patients with a psychotic disorder (n = 31) and healthy controls (n = 25). Carriers of the COMT Val(158)Met Val allele, but not subjects with the Met/Met genotype, showed an increase in hallucinations after cannabis exposure, conditional on prior evidence of psychometric psychosis liability. The findings confirm that in people with psychometric evidence of psychosis liability, COMT Val(158)Met genotype moderates the association between cannabis and psychotic phenomena in the flow of daily life.

Differential Genetic and Epigenetic Regulation of catechol-O-methyltransferase is Associated with Impaired Fear Inhibition in Posttraumatic Stress Disorder.

PubMed

Norrholm, Seth Davin; Jovanovic, Tanja; Smith, Alicia K; Binder, Elisabeth; Klengel, Torsten; Conneely, Karen; Mercer, Kristina B; Davis, Jennifer S; Kerley, Kimberly; Winkler, Jennifer; Gillespie, Charles F; Bradley, Bekh; Ressler, Kerry J

2013-01-01

The catechol-O-methyltransferase (COMT) enzyme is critical for the catabolic regulation of synaptic dopamine, resulting in altered cortical functioning. The COMT Val(158)Met polymorphism has been implicated in human mental illness, with Met/Met homozygotes associated with increased susceptibility to posttraumatic stress disorder (PTSD). Our primary objective was to examine the intermediate phenotype of fear inhibition in PTSD stratified by COMT genotype (Met/Met, Val/Met, and Val/Val) and differential gene regulation via methylation status at CpG sites in the COMT promoter region. More specifically, we examined the potential interaction of COMT genotype and PTSD diagnosis on fear-potentiated startle during fear conditioning and extinction and COMT DNA methylation levels (as determined using genomic DNA isolated from whole blood). Participants were recruited from medical and gynecological clinics of an urban hospital in Atlanta, GA, USA. We found that individuals with the Met/Met genotype demonstrated higher fear-potentiated startle to the CS- (safety signal) and during extinction of the CS+ (danger signal) compared to Val/Met and Val/Val genotypes. The PTSD+ Met/Met genotype group had the greatest impairment in fear inhibition to the CS- (p = 0.006), compared to Val carriers. In addition, the Met/Met genotype was associated with DNA methylation at four CpG sites, two of which were associated with impaired fear inhibition to the safety signal. These results suggest that multiple differential mechanisms for regulating COMT function - at the level of protein structure via the Val(158)Met genotype and at the level of gene regulation via differential methylation - are associated with impaired fear inhibition in PTSD.

Schooling and variation in the COMT gene: The devil is in the details

PubMed Central

Campbell, Daniel; Bick, Johanna; Yrigollen, Carolyn M.; Lee, Maria; Joseph, Antony; Chang, Joseph T.; Grigorenko, Elena L.

2013-01-01

Background Schooling is considered to be one of the major contributors to the development of intelligence within societies and individuals. Genetic variation might modulate the impact of schooling and explain, at least partially, the presence of individual differences in classrooms. Method We studied a sample of 1502 children (mean age = 11.7 years) from Zambia. Approximately 57% of these children were enrolled in school, and the rest were not. To quantify genetic variation, we investigated a number of common polymorphisms in the catechol-O-methyltransferase (COMT) gene that controls the production of the protein thought to account for >60% of the dopamine degradation in the prefrontal cortex. Results Haplotype analyses generated results ranging from the presence to absence of significant interactions between a number of COMT haplotypes and indicators of schooling (i.e., in- vs. out-of-school and grade completed) in the prediction of nonverbal intelligence, depending on the parameter specification. However, an investigation of the distribution of corresponding p-values suggested that these positive results were false. Conclusions Convincing evidence that the variation in the COMT gene is associated with individual differences in nonverbal intelligence either directly or through interactions with schooling was not found. P-values produced by the method of testing for haplotype effects employed here may be sensitive to parameter settings, invalid under default settings, and should be checked for validity through simulation. PMID:23952646

Common Variants in LRP2 and COMT Genes Affect the Susceptibility of Gout in a Chinese Population

PubMed Central

Zhou, Jingru; Qian, Qiaoxia; Ma, Yanyun; He, Hongjun; Ji, Hengdong; Yang, Yajun; Wang, Xiaofeng; Xu, Xia; Pang, Yafei; Zou, Hejian; Jin, Li; Wang, Jiucun

2015-01-01

Gout is a common inflammation disease resulting from an increase in serum uric acid. Nearly 70% of uric acid is excreted via the kidneys. To date, evidence for an association between genetic loci and gout is absent, equivocal or not replicated. Our study aims to test variants in two genes abundantly expressed in the kidney, LRP2 and COMT, for their association with uric acid and gout. In total, 1318 Chinese individuals were genotyped for rs2544390 in LRP2 and rs4680 in COMT. These LRP2 and COMT gene polymorphisms showed no significant effect on uric acid (P = 0.204 and 0.188, separately); however, rs2544390 in LRP2 did influence uric acid levels in individuals with BMI ≥ 25 (P = 0.009). In addition, the allele frequency distributions of the two loci showed a significant difference between gout patients and healthy controls. A missense variation in rs4680 (G > A) decreased the risk of gout (OR = 0.77, P = 0.015), whereas the T allele of rs2544390 was associated with gout pathogenesis risk (OR = 1.26, P = 0.020). The present study provides the first evidence for an association between COMT and gout. Rs2544390 in LRP2 only influenced uric acid levels in individuals with BMI ≥ 25, which might explain the discrepant results among previous studies. In addition, we are the first to identify the association between LRP2 and gout in a Chinese population and to confirm this association in Asians. PMID:26147675

Common Variants in LRP2 and COMT Genes Affect the Susceptibility of Gout in a Chinese Population.

PubMed

Dong, Zheng; Zhao, Dongbao; Yang, Chengde; Zhou, Jingru; Qian, Qiaoxia; Ma, Yanyun; He, Hongjun; Ji, Hengdong; Yang, Yajun; Wang, Xiaofeng; Xu, Xia; Pang, Yafei; Zou, Hejian; Jin, Li; Wang, Jiucun

2015-01-01

Gout is a common inflammation disease resulting from an increase in serum uric acid. Nearly 70% of uric acid is excreted via the kidneys. To date, evidence for an association between genetic loci and gout is absent, equivocal or not replicated. Our study aims to test variants in two genes abundantly expressed in the kidney, LRP2 and COMT, for their association with uric acid and gout. In total, 1318 Chinese individuals were genotyped for rs2544390 in LRP2 and rs4680 in COMT. These LRP2 and COMT gene polymorphisms showed no significant effect on uric acid (P = 0.204 and 0.188, separately); however, rs2544390 in LRP2 did influence uric acid levels in individuals with BMI ≥ 25 (P = 0.009). In addition, the allele frequency distributions of the two loci showed a significant difference between gout patients and healthy controls. A missense variation in rs4680 (G > A) decreased the risk of gout (OR = 0.77, P = 0.015), whereas the T allele of rs2544390 was associated with gout pathogenesis risk (OR = 1.26, P = 0.020). The present study provides the first evidence for an association between COMT and gout. Rs2544390 in LRP2 only influenced uric acid levels in individuals with BMI ≥ 25, which might explain the discrepant results among previous studies. In addition, we are the first to identify the association between LRP2 and gout in a Chinese population and to confirm this association in Asians.

Sleep and COMT Polymorphism in ADHD Children: Preliminary Actigraphic Data

ERIC Educational Resources Information Center

Gruber, Reut; Grizenko, Natalie; Schwartz, George; Amor, Leila Ben; Gauthier, Julie; de Guzman, Rosherrie; Joober, Ridha

2006-01-01

Objective: To examine whether COMT (catechol-O-methyltransferase) polymorphism modulates aspects of sleep in children diagnosed with attention-deficit/hyperactivity disorder (ADHD). Method: Nightly sleep actigraphic recordings during a double-blind, placebo-controlled, crossover clinical study (1 week of 0.5 mg/kg MPH; 1 week of placebo) were…

Modification of depression by COMT val158met polymorphism in children exposed to early severe psychosocial deprivation

PubMed Central

Drury, Stacy S; Theall, Katherine P; Smyke, Anna T; Keats, Bronya JB; Egger, Helen L; Nelson, Charles A; Fox, Nathan A; Marshall, Peter J; Zeanah, Charles H

2014-01-01

Objective To examine the impact of the Catechol-O-Methyltransferase (COMT) val158met allele on depressive symptoms in young children exposed to early severe social deprivation as a result of being raised in institutions. Methods 136 children from the Bucharest Early Intervention Project (BEIP) were randomized before 31 months of age to either care as usual (CAU) in institutions or placement in newly created foster care (FCG). At 54 months of age, a psychiatric assessment using the Preschool Age Psychiatric Assessment (PAPA) was completed. DNA was collected and genotyped for the COMT val158met polymorphism. Multivariate analysis examined the relationship between COMT alleles and depressive symptoms. Results Mean level of depressive symptoms was lower among participants with the met allele compared to those with two copies of the val allele (p <0.05). Controlling for group and gender, the rate of depressive symptoms was significantly lower among participants with the met/met or the met/val genotype (adjusted relative risk (aRR) = 0.67, 95% CI = 0.45, 0.99) compared to participants with the val/val genotype, indicating an intermediate impact for heterozygotes consistent with the biological impact of this polymorphism. The impact of genotype within groups differed significantly. There was a significant protective effect of the met allele on depressive symptoms within the CAU group, however there was no relationship seen within the FCG group. Conclusions This is the first study, to our knowledge, to find evidence of a gene × environment interaction in the setting of early social deprivation. These results support the hypothesis that individual genetic differences may explain some of the variability in recovery amongst children exposed to early severe social deprivation. PMID:20403637

Genetic moderation of the effects of cannabis: catechol-O-methyltransferase (COMT) affects the impact of Δ9-tetrahydrocannabinol (THC) on working memory performance but not on the occurrence of psychotic experiences.

PubMed

Tunbridge, Elizabeth M; Dunn, Graham; Murray, Robin M; Evans, Nicole; Lister, Rachel; Stumpenhorst, Katharina; Harrison, Paul J; Morrison, Paul D; Freeman, Daniel

2015-11-01

Cannabis use can induce cognitive impairments and psychotic experiences. A functional polymorphism in the catechol-O-methyltransferase (COMT) gene (Val(158)Met) appears to influence the immediate cognitive and psychotic effects of cannabis, or ∆(9)-tetrahydrocannabinol (THC), its primary psychoactive ingredient. This study investigated the moderation of the impact of experimentally administered THC by COMT. Cognitive performance and psychotic experiences were studied in participants without a psychiatric diagnosis, using a between-subjects design (THC vs. placebo). The effect of COMT Val(158)Met genotype on the cognitive and psychotic effects of THC, administered intravenously in a double-blind, placebo-controlled manner to 78 participants who were vulnerable to paranoia, was examined. The results showed interactive effects of genotype and drug group (THC or placebo) on working memory, assayed using the Digit Span Backwards task. Specifically, THC impaired performance in COMT Val/Val, but not Met, carriers. In contrast, the effect of THC on psychotic experiences, measured using the Community Assessment of Psychic Experiences (CAPE) positive dimension, was unaffected by COMT genotype. This study is the largest to date examining the impact of COMT genotype on response to experimentally administered THC, and the first using a purely non-clinical cohort. The data suggest that COMT genotype moderates the cognitive, but not the psychotic, effects of acutely administered THC. © The Author(s) 2015.

Epistatic interactions involving DRD2, DRD4, and COMT polymorphisms and risk of substance abuse in women with binge-purge eating disturbances.

PubMed

Steiger, Howard; Thaler, Lea; Gauvin, Lise; Joober, Ridha; Labbe, Aurelie; Israel, Mimi; Kucer, Audrey

2016-06-01

Substance abuse is common in individuals with bulimia-spectrum (binge-purge) eating disturbances, a co-occurrence that has been attributed to shared neurobiological substrates--notably alterations in dopaminergic activity. We examined the implications of variations of selected, dopamine-relevant polymorphisms (DRD2 Taq1A, DRD4 7R, and COMT) for risk of substance abuse in women with binge-purge eating syndromes. We genotyped 183 women (66.1% showing full-threshold BN and 33.9% showing sub-syndromic variants), and assessed lifetime presence of alcohol, cannabis, cocaine, and stimulant abuse or dependence using structured interviews. Tests for main and interaction effects of various allele combinations revealed that individuals who carried high function COMT and low-function DRD4 7R alleles (a combination expected to be associated with higher risk) did indeed show more lifetime substance abuse and, specifically, more cannabis abuse. Our findings suggest that a gene combination that, in theory, codes for low levels of dopaminergic neurotransmission coincides with sensitivity to substance abuse in a sample displaying binge-purge eating-disorder variants. Copyright © 2016 Elsevier Ltd. All rights reserved.

COMT and MTHFR polymorphisms interaction on cognition in schizophrenia: an exploratory study.

PubMed

Kontis, Dimitrios; Theochari, Eirini; Fryssira, Helen; Kleisas, Spyridon; Sofocleous, Christalena; Andreopoulou, Angeliki; Kalogerakou, Stamatina; Gazi, Anthia; Boniatsi, Lucia; Chaidemenos, Alexandros; Tsaltas, Eleftheria

2013-03-14

The investigation of the catechol-O-methyltransferase (COMT-[rs4680]) and methylenetetrahydrofolate reductase (MTHFR-[rs1801133]) polymorphisms' interaction might shed light into the pathogenetic mechanisms of the cognitive dysfunction in schizophrenia. In an exploratory study, we hypothesized that the MTHFR 677T allele which has been related to a hypoactive MTHFR enzyme would augment the unfavorable effects of COMT Val158 homozygosity which has been associated with COMT enzyme hyperfunction. 90 schizophrenia patients and 55 healthy volunteers were assessed on psychomotor speed, pattern and spatial recognition memory (SRM), spatial working memory (SWM), attentional flexibility and planning (Stockings of Cambridge-SOC). IQ scores in a random subgroup of patients were also measured. A significant COMT×MTHFR interaction on SWM (p=0.048) and planning (p=0.026) was revealed in both groups. Among COMT-Val/Val participants, MTHFR-C/C made more SWM errors (p=0.033) and solved fewer SOC problems (p=0.025) than MTHFR-T carriers. In patients, there was a significant COMT×MTHFR interaction on full scale IQ (p=0.035): among COMT-Met carriers, MTHFR-T carriers performed significantly worse than MTHFR-C/C (p=0.021), which was driven by a COMT×MTHFR interaction involving performance IQ (p=0.047). In conclusion, COMT and MTHFR polymorphisms interacted on cognition, suggesting that the MTHFR enzyme activity might moderate the effects of the COMT enzyme. In contrast to our initial hypothesis, the MTHFR T-allele attenuated the cognitive effects of COMT Val homozygosity. In this preliminary study, we propose that dopaminergic and intracellular methylation mechanisms could interact on cognitive deficits in schizophrenia. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

The activity of catechol-O-methyltransferase (COMT) is not impaired by high doses of epigallocatechin-3-gallate (EGCG) in vivo.

PubMed

Lorenz, Mario; Paul, Friedemann; Moobed, Minoo; Baumann, Gert; Zimmermann, Benno F; Stangl, Karl; Stangl, Verena

2014-10-05

Catechol-O-methyltransferase (COMT) inactivates many endogenous and exogenous compounds by O-methylation. Therefore, it represents a major enzyme of the metabolic pathway with important biological functions in hormonal and drug metabolism. The tea catechin epigallocatechin-3-gallate (EGCG) is known to inhibit COMT enzymatic activity in vitro. Based on beneficial in vitro results, EGCG is extensively used in human intervention studies in a variety of human diseases. Owing to its low bioavailability, rather high doses of EGCG are frequently applied that may impair COMT activity in vivo. Enzymatic activities of four functional COMT single-nucleotide polymorphisms (SNPs) were determined in red blood cells (RBCs) in 24 healthy human volunteers (14 women, 10 men). The subjects were supplemented with 750 mg of EGCG and EGCG plasma levels and COMT enzyme activities in erythrocytes were measured before and 2 h after intervention. The homozygous Val→Met substitution in the SNP rs4680 resulted in significantly decreased COMT activity. Enzymatic COMT activities in RBCs were also affected by the other three COMT polymorphisms. EGCG plasma levels significantly increased after intervention. They were not influenced by any of the COMT SNPs and different enzyme activities. Ingestion of 750 mg EGCG did not result in impairment of COMT activity. However, COMT activity was significantly increased by 24% after EGCG consumption. These results indicate that supplementation with a high dose of EGCG does not impair the activity of COMT. Consequently, it may not interfere with COMT-mediated metabolism and elimination of exogenous and endogenous COMT substrates. Copyright © 2014 Elsevier B.V. All rights reserved.

Association of Catechol-O-methyltransferase polymorphism Val158Met and mammographic density: A meta-analysis.

PubMed

Kallionpää, Roope A; Uusitalo, Elina; Peltonen, Juha

2017-08-15

The Val158Met polymorphism in catechol-O-methyltransferase (COMT) enzyme reduces the methylation of catechol estrogens, which may affect mammographic density. High mammographic density is a known risk factor of breast cancer. Our aim was to perform meta-analysis of the effect of COMT Val158Met polymorphism on mammographic density. Original studies reporting data on mammographic density, stratified by the presence of COMT Val158Met polymorphism, were identified and combined using genetic models Met/Val vs. Val/Val, Met/Met vs. Val/Val, Val/Met+Met/Met vs. Val/Val (dominant model) and Met/Met vs. Val/Met+Val/Val (recessive model). Subgroup analyses by breast cancer status, menopausal status and use of hormone replacement therapy (HRT) were also performed. Eight studies were included in the meta-analysis. The overall effect in percent mammographic density was -1.41 (CI -2.86 to 0.05; P=0.06) in the recessive model. Exclusion of breast cancer patients increased the effect size to -1.93 (CI -3.49 to -0.37; P=0.02). The results suggested opposite effect of COMT Val158Met for postmenopausal users of HRT versus premenopausal women or postmenopausal non-users of HRT. COMT Val158Met polymorphism may be associated with mammographic density at least in healthy women. Menopausal status and HRT should be taken into account in future studies to avoid masking of the underlying effects. Copyright © 2017 Elsevier B.V. All rights reserved.

Pilot study of association of catechol-O-methyl transferase rs4680 genotypes with acute kidney injury and tubular stress after open heart surgery.

PubMed

Albert, Christian; Kube, Johanna; Haase-Fielitz, Anja; Dittrich, Annemarie; Schanze, Denny; Zenker, Martin; Kuppe, Hermann; Hetzer, Roland; Bellomo, Rinaldo; Mertens, Peter R; Haase, Michael

2014-01-01

To assess the association of genetic variants of catecholamine-O-methyltransferase (COMT) genotypes with acute kidney injury (AKI) and tubular stress after open heart surgery. We genotyped 195 patients for the COMT-Val158Met polymorphism and measured creatinine, neutrophil gelatinase-associated lipocalin and midkine. We analyzed the association between such polymorphisms and these kidney-related variables. Nonsignificantly more COMT LL patients developed RIFLE-AKI compared with non-LL patients (p = 0.11). Compared with HL and HH patients, LL patients who developed AKI had lower increases in serum creatinine. COMT LL patients had less pronounced release of tubular stress biomarkers (neutrophil gelatinase-associated lipocalin: p = 0.045, midkine: p = 0.072). COMT genotype may associate with different patterns of renal functional changes and tubular stress biomarker release response after open heart surgery.

Modulating effect of COMT Val(158)Met polymorphism on interference resolution during a working memory task.

PubMed

Jaspar, Mathieu; Dideberg, Vinciane; Bours, Vincent; Maquet, Pierre; Collette, Fabienne

2015-04-01

Genetic variability related to the catechol-O-methyltransferase (COMT) gene has received increasing attention in the last 15years, in particular as a potential modulator of the neural substrates underlying inhibitory processes and updating in working memory (WM). In an event-related functional magnetic resonance imaging (fMRI) study, we administered a modified version of the Sternberg probe recency task (Sternberg, 1966) to 43 young healthy volunteers, varying the level of interference across successive items. The task was divided into two parts (high vs. low interference) to induce either proactive or reactive control processes. The participants were separated into three groups according to their COMT Val(158)Met genotype [Val/Val (VV); Val/Met (VM); Met/Met (MM)]. The general aim of the study was to determine whether COMT polymorphism has a modulating effect on the neural substrates of interference resolution during WM processing. Results indicate that interfering trials were associated with greater involvement of frontal cortices (bilateral medial frontal gyrus, left precentral and superior frontal gyri, right inferior frontal gyrus) in VV homozygous subjects (by comparison to Met allele carriers) only in the proactive condition of the task. In addition, analysis of peristimulus haemodynamic responses (PSTH) revealed that the genotype-related difference observed in the left SFG was specifically driven by a larger increase in activity from the storage to the recognition phase of the interfering trials in VV homozygous subjects. These results confirm the impact of COMT genotype on inhibitory processes during a WM task, with an advantage for Met allele carriers. Interestingly, this impact on frontal areas is present only when the level of interference is high, and especially during the transition from storage to recognition in the left superior frontal gyrus. Copyright © 2015 Elsevier Inc. All rights reserved.

The divergent impact of catechol-O-methyltransferase (COMT) Val158Met genetic polymorphisms on executive function in adolescents with discrete patterns of childhood adversity.

PubMed

Zhang, Huihui; Li, Jie; Yang, Bei; Ji, Tao; Long, Zhouting; Xing, Qiquan; Shao, Di; Bai, Huayu; Sun, Jiwei; Cao, Fenglin

2018-02-01

Catechol-O-methyltransferase (COMT) Val 158 Met functional polymorphisms play a crucial role in the development of executive function (EF), but their effect may be moderated by environmental factors such as childhood adversity. The present study aimed at testing the divergent impact of the COMT Val 158 Met genotype on EF in non-clinical adolescents with discrete patterns of childhood adversity. A total of 341 participants completed the Childhood Trauma Questionnaire, the self-reported version of the Behavior Rating Inventory of Executive Function, and self-administered questionnaires on familial function. The participants' COMT Val 158 Met genotype was determined. Associations among the variables were explored using latent class analysis and general linear models. We found that Val/Val homozygotes showed significantly worse performance on behavioral shift, relative to Met allele carriers (F=5.921, p=0.015, Partial η 2 =0.018). Moreover, three typical patterns of childhood adversity, namely, low childhood adversity (23.5%), childhood neglect (59.8%), and high childhood adversity (16.7%), were found. Both childhood neglect and high childhood adversity had a negative impact on each aspect of EF and on global EF performance. Importantly, these results provided evidence for significant interaction effects, as adolescents with the Val/Val genotype showed inferior behavioral shift performance than Met carriers (F=6.647, p=0.010, Partial η 2 =0.020) in the presence of high childhood adversity. Furthermore, there were no differences between the genotypes for childhood neglect and low childhood adversity. Overall, this is the first study to show that an interaction between the COMT genotype and childhood adversity affects EF in non-clinical adolescents. These results suggest that the COMT genotype may operate as a susceptibility gene vulnerable to an adverse environment. Copyright © 2017 Elsevier Inc. All rights reserved.

Differences in Cognitive Outcomes After ECT Depending on BDNF and COMT Polymorphisms.

PubMed

Bennett, Daniel Mark; Currie, James; Fernie, Gordon; Perrin, Jennifer S; Reid, Ian C

2016-12-01

The study aimed to explore cognitive outcomes after electroconvulsive therapy (ECT) depending on which version of common single nucleotide polymorphisms the patient expressed for brain-derived neurotrophic factor (BDNF) and catechol-O-methyltransferase (COMT). A total of 87 patients from the clinical ECT service in Aberdeen, Scotland, were included in the study. Cognitive function testing (using Spatial Recognition Memory task from the Cambridge Neuropsychological Test Automated Battery and Mini-Mental State Examination) and mood ratings (Montgomery-Åsberg Depression Rating Scale) were performed before ECT, after 4 treatments, at the end of ECT and 1 and 3 months after the end of treatment. These scores were compared depending on BDNF and COMT variant at each time point using the Student t test and using a time series generalized least squares random effects model. No differences were found between the val and met versions of the BDNF or COMT polymorphism in either cognitive or mood outcomes at any time point during ECT treatment or up to 3 months of follow-up. This study did not detect significant differences in cognitive or mood outcomes between patients who have the val66val or met versions of the BDNF polymorphism. Our results suggest that these polymorphisms will not be helpful in clinical practice for predicting cognitive outcomes after ECT.

Schooling and variation in the COMT gene: the devil is in the details.

PubMed

Campbell, Daniel; Bick, Johanna; Yrigollen, Carolyn M; Lee, Maria; Joseph, Antony; Chang, Joseph T; Grigorenko, Elena L

2013-10-01

Schooling is considered one of the major contributors to the development of intelligence within societies and individuals. Genetic variation might modulate the impact of schooling and explain, at least partially, the presence of individual differences in classrooms. We studied a sample of 1,502 children (mean age = 11.7 years) from Zambia. Approximately 57% of these children were enrolled in school, and the rest were not. To quantify genetic variation, we investigated a number of common polymorphisms in the catechol-O-methyltransferase (COMT) gene that controls the production of the protein thought to account for >60% of the dopamine degradation in the prefrontal cortex. Haplotype analyses generated results ranging from the presence to absence of significant interactions between a number of COMT haplotypes and indicators of schooling (i.e., in- vs. out-of-school and grade completed) in the prediction of nonverbal intelligence, depending on the parameter specification. However, an investigation of the distribution of corresponding p-values suggested that these positive results were false. Convincing evidence that the variation in the COMT gene is associated with individual differences in nonverbal intelligence either directly or through interactions with schooling was not found. p-values produced by the method of testing for haplotype effects employed here may be sensitive to parameter settings, invalid under default settings, and should be checked for validity through simulation. © 2013 The Authors. Journal of Child Psychology and Psychiatry © 2013 Association for Child and Adolescent Mental Health.

Age-Dependent Effects of Catechol-O-Methyltransferase (COMT) Gene Val158Met Polymorphism on Language Function in Developing Children.

PubMed

Sugiura, Lisa; Toyota, Tomoko; Matsuba-Kurita, Hiroko; Iwayama, Yoshimi; Mazuka, Reiko; Yoshikawa, Takeo; Hagiwara, Hiroko

2017-01-01

The genetic basis controlling language development remains elusive. Previous studies of the catechol-O-methyltransferase (COMT) Val158Met genotype and cognition have focused on prefrontally guided executive functions involving dopamine. However, COMT may further influence posterior cortical regions implicated in language perception. We investigated whether COMT influences language ability and cortical language processing involving the posterior language regions in 246 children aged 6-10 years. We assessed language ability using a language test and cortical responses recorded during language processing using a word repetition task and functional near-infrared spectroscopy. The COMT genotype had significant effects on language performance and processing. Importantly, Met carriers outperformed Val homozygotes in language ability during the early elementary school years (6-8 years), whereas Val homozygotes exhibited significant language development during the later elementary school years. Both genotype groups exhibited equal language performance at approximately 10 years of age. Val homozygotes exhibited significantly less cortical activation compared with Met carriers during word processing, particularly at older ages. These findings regarding dopamine transmission efficacy may be explained by a hypothetical inverted U-shaped curve. Our findings indicate that the effects of the COMT genotype on language ability and cortical language processing may change in a narrow age window of 6-10 years. © The Author 2016. Published by Oxford University Press.

Catechol-O-Methyltransferase "Val[superscript 158]Met" Genotype, Parenting Practices and Adolescent Alcohol Use: Testing the Differential Susceptibility Hypothesis

ERIC Educational Resources Information Center

Laucht, Manfred; Blomeyer, Dorothea; Buchmann, Arlette F.; Treutlein, Jens; Schmidt, Martin H.; Esser, Gunter; Jennen-Steinmetz, Christine; Rietschel, Marcella; Zimmermann, Ulrich S.; Banaschewski, Tobias

2012-01-01

Background: Recently, first evidence has been reported for a gene-parenting interaction (G x E) with regard to adolescent alcohol use. The present investigation set out to extend this research using the catechol-O-methyltransferase ("COMT") "Val[superscript 158]Met" polymorphism as a genetic susceptibility factor. Moreover, the current study…

COMT met allele differentially predicts risk versus severity of aberrant eating in a large community sample.

PubMed

Donofry, Shannon D; Roecklein, Kathryn A; Wildes, Jennifer E; Miller, Megan A; Flory, Janine D; Manuck, Stephen B

2014-12-15

Prefrontal dopamine (DA) transmission participates in the reinforcement of reward-driven behaviors like eating. Because catechol-O-methyltransferase (COMT) degrades DA and is expressed in the prefrontal cortex, variation in the COMT gene may modulate eating behavior. Previous studies have shown that the met allele of the COMT val158met single nucleotide polymorphism (SNP) is associated with Bulimia Nervosa (BN). The specific aim of this study was to test whether the met allele increased risk for, and severity of, eating disorder symptomatology in community volunteers. Caucasian adults (N=1003; 51.2% female) from the University of Pittsburgh Adult Health and Behavior Project (AHAB) were genotyped and completed the Eating Disorders Inventory (EDI). Logistic and Poisson regression analyses assessed genotype-dependent presence and severity of eating disorder symptomatology. The met allele was significantly associated with the presence of symptoms on the Bulimia subscale and the severity of Body Dissatisfaction scores. All EDI subscales significantly predicted BMI. To our knowledge, these are the first data indicating that the COMT met allele increases risk for some symptoms of disordered eating, while increasing severity of others, in a community sample. These novel findings may have important implications for understanding the etiology of heterogeneous disordered eating phenotypes. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

The influence of CHRNA4, COMT, and maternal sensitivity on orienting and executive attention in 6-month-old infants.

PubMed

Quan, Jeffry; Ong, Mei-Lyn; Bureau, Jean-Francois; Sim, Lit Wee; Sanmugam, Shamini; Abdul Malik, Adam B; Wong, Eric; Wong, Johnny; Chong, Yap-Seng; Saw, Seang Mei; Kwek, Kenneth; Qiu, Anqi; Holbrook, Joanna D; Rifkin-Graboi, Anne

2017-08-01

Despite claims concerning biological mechanisms sub-serving infant attention, little experimental work examines its underpinnings. This study examines how candidate polymorphisms from the cholinergic (CHRNA4 rs1044396) and dopaminergic (COMT rs4680) systems, respectively indicative of parietal and prefrontal/anterior cingulate involvement, are related to 6-month-olds' (n=217) performance during a visual expectation eye-tracking paradigm. As previous studies suggest that both cholinergic and dopaminergic genes may influence susceptibility to the influence of other genetic and environmental factors, we further examined whether these candidate genes interact with one another and/or with early caregiving experience in predicting infants' visual attention. We detected an interaction between CHRNA4 genotype and observed maternal sensitivity upon infants' orienting to random stimuli and a CHRNA4-COMT interaction effect upon infants' orienting to patterned stimuli. Consistent with adult research, we observed a direct effect of COMT genotype on anticipatory looking to patterned stimuli. Findings suggest that CHRNA4 genotype may influence susceptibility to other attention-related factors in infancy. These interactions may account for the inability to establish a link between CHRNA4 and orienting in infant research to date, despite developmental theorizing suggesting otherwise. Moreover, findings suggest that by 6months, dopamine, and relatedly, the prefrontal cortex/anterior cingulate, may be important to infant attention. Copyright © 2017 Elsevier Inc. All rights reserved.

COMT haplotypes modulate associations of antenatal maternal anxiety and neonatal cortical morphology.

PubMed

Qiu, Anqi; Tuan, Ta Anh; Ong, Mei Lyn; Li, Yue; Chen, Helen; Rifkin-Graboi, Anne; Broekman, Birit F P; Kwek, Kenneth; Saw, Seang-Mei; Chong, Yap-Seng; Gluckman, Peter D; Fortier, Marielle V; Holbrook, Joanna Dawn; Meaney, Michael J

2015-02-01

Exposure to antenatal maternal anxiety and complex genetic variations may shape fetal brain development. In particular, the catechol-O-methyltransferase (COMT) gene, located on chromosome 22q11.2, regulates catecholamine signaling in the prefrontal cortex and is implicated in anxiety, pain, and stress responsivity. This study examined whether individual single-nucleotide polymorphisms (SNPs) of the COMT gene and their haplotypes moderate the association between antenatal maternal anxiety and in utero cortical development. A total of 146 neonates were genotyped and underwent MRI shortly after birth. Neonatal cortical morphology was characterized using cortical thickness. Antenatal maternal anxiety was assessed using the State-Trait Anxiety Inventory at week 26 of pregnancy. Individual COMT SNPs (val158met, rs737865, and rs165599) modulated the association between antenatal maternal anxiety and the prefrontal and parietal cortical thickness in neonates. Based on haplotype trend regression analysis, findings also showed that among rs737865-val158met-rs165599 haplotypes, the A-val-G (AGG) haplotype probabilities modulated positive associations of antenatal maternal anxiety with cortical thickness in the right ventrolateral prefrontal cortex and the right superior parietal cortex and precuneus. In contrast, the G-met-A (GAA) haplotype probabilities modulated negative associations of antenatal maternal anxiety with cortical thickness in bilateral precentral gyrus and the dorsolateral prefrontal cortex. These results suggest that the association between maternal anxiety and in utero neurodevelopment is modified through complex genetic variation in COMT. Such genetic moderation may explain, in part, the variation in phenotypic outcomes in offspring associated with maternal emotional well-being.

Genetic polymorphisms involved in dopaminergic neurotransmission and risk for Parkinson's disease in a Japanese population

PubMed Central

2011-01-01

Background Parkinson's disease (PD) is characterized by alterations in dopaminergic neurotransmission. Genetic polymorphisms involved in dopaminergic neurotransmission may influence susceptibility to PD. Methods We investigated the relationship of catechol-O-methyltransferase (COMT), monoamine oxidase B (MAOB), dopamine receptor (DR) D2 and DRD4 polymorphisms and PD risk with special attention to the interaction with cigarette smoking among 238 patients with PD and 369 controls in a Japanese population. Results Subjects with the AA genotype of MAOB rs1799836 showed a significantly increased risk of PD (odds ratio (OR) = 1.70, 95% confidence interval (CI) = 1.12 - 2.58) compared with the AG and GG genotypes combined. The AA genotype of COMT rs4680 was marginally associated with an increased risk of PD (OR = 1.86, 95% CI = 0.98 - 3.50) compared with the GG genotype. The DRD2 rs1800497 and DRD4 rs1800955 polymorphisms showed no association with PD. A COMT -smoking interaction was suggested, with the combined GA and AA genotypes of rs4680 and non-smoking conferring significantly higher risk (OR = 3.97, 95% CI = 2.13 - 7.41) than the AA genotype and a history of smoking (P for interaction = 0.061). No interactions of smoking with other polymorphisms were observed. Conclusions The COMT rs4680 and MAOB rs1799836 polymorphisms may increase susceptibility to PD risk among Japanese. Future studies involving larger control and case populations and better pesticide exposure histories will undoubtedly lead to a more thorough understanding of the role of the polymorphisms involved in the dopamine pathway in PD. PMID:21781348

Influence of SLC6A3 and COMT Variation on Neural Activation During Response Inhibition

PubMed Central

Congdon, Eliza; Constable, R. Todd; Lesch, Klaus Peter; Canli, Turhan

2009-01-01

There is evidence concerning the neural and genetic correlates of inhibitory control, but there have been limited attempts to combine this information. This study tested the hypothesis that two dopaminergic polymorphisms, SLC6A3 and COMT, influence neural activation during response inhibition. Healthy adults were genotyped for these polymorphisms and performed a measure of response inhibition while undergoing functional magnetic resonance imaging (fMRI). Results support the role of key frontostriatal regions underlying response inhibition. Furthermore, results support a significant influence of SLC6A3 and COMT variants on neural activity during inhibition, with greater activation during inhibition in carriers of the SLC6A3 9-allele or the COMT met-allele as compared to carriers of the SLC6A3 10/10 genotype or the COMT val/val genotype. These results add to a growing literature suggesting that inhibitory control is sensitive to variation in dopamine function, and suggest that this variation may be detectable at the level of individuals’ genotypes. PMID:19482231

COMT Val158Met Polymorphism and Symptom Improvement Following a Cognitively-Focused Intervention for Irritable Bowel Syndrome

PubMed Central

Han, Claire J.; Kohen, Ruth; Jun, Sangeun; Jarrett, Monica E.; Cain, Kevin C.; Burr, Robert; Heitkemper, Margaret M.

2016-01-01

Background Our nurse-delivered Comprehensive Self-Management (CSM) program, a cognitive behavioral therapy intervention, is effective in reducing gastrointestinal and psychological distress symptoms in patients with irritable bowel syndrome (IBS). Findings from non-IBS studies indicate that the catechol-O-methyltransferase (COMT) Val158Met polymorphism may moderate the efficacy of cognitive behavioral therapy. It is unknown whether this COMT polymorphism is associated with symptom improvements in patients with IBS. Objective We tested whether this COMT Val158Met polymorphism influences the efficacy of our two-month CSM intervention. Methods We analyzed data from two published randomized controlled trials of CSM. The combined European-American sample included 149 women and 23 men with IBS (CSM, n =111; Usual Care [UC], n = 61). The primary outcomes were daily reports of abdominal pain, depression, anxiety, and feeling stressed measured three and six months after randomization. Secondary outcomes were additional daily symptoms, retrospective psychological distress, IBS quality of life, and cognitive beliefs about IBS. The interaction between COMT Val158Met polymorphism and treatment group (CSM vs. UC) in a generalized estimating equation model tested the main objective. Results At three months, participants with at least one Val allele benefited more from CSM than did those with the Met/Met genotype (p = .01 for anxiety and feeling stressed, and p < .16 for abdominal pain and depression). The moderating effect of genotype was weaker at six months. Discussion Persons with at least one Val allele may benefit more from CSM than those homozygous for the Met allele. Future studies with larger and more racially diverse samples are needed to confirm these findings. RCT Registration Parent studies were registered at ClinicalTrials.gov (NCT00167635 and NCT00907790). PMID:28252569

The modulatory influence of the functional COMT Val158Met polymorphism on lexical decisions and semantic priming.

PubMed

Reuter, Martin; Montag, Christian; Peters, Kristina; Kocher, Anne; Kiefer, Markus

2009-01-01

The role of the prefrontal Cortex (PFC) in higher cognitive functions - including working memory, conflict resolution, set shifting and semantic processing - has been demonstrated unequivocally. Despite the great heterogeneity among tasks measuring these phenotypes, due in part to the different cognitive sub-processes implied and the specificity of the stimulus material used, there is agreement that all of these tasks recruit an executive control system located in the PFC. On a biochemical level it is known that the dopaminergic system plays an important role in executive control functions. Evidence comes from molecular genetics relating the functional COMT Val158Met polymorphism to working memory and set shifting. In order determine whether this pattern of findings generalises to linguistic and semantic processing, we investigated the effects of the COMT Val158Met polymorphism in lexical decision making using masked and unmasked versions of the semantic priming paradigm on N = 104 healthy subjects. Although we observed strong priming effects in all conditions (masked priming, unmasked priming with short/long stimulus asynchronies (SOAs), direct and indirect priming), COMT was not significantly related to priming, suggesting no reliable influence on semantic processing. However, COMT Val158Met was strongly associated with lexical decision latencies in all priming conditions if considered separately, explaining between 9 and 14.5% of the variance. Therefore, the findings indicate that COMT mainly influences more general executive control functions in the PFC supporting the speed of lexical decisions.

Interactive effects of the COMT gene and training on individual differences in supervisory control of unmanned vehicles.

PubMed

Parasuraman, Raja; Kidwell, Brian; Olmstead, Ryan; Lin, Ming-Kuan; Jankord, Ryan; Greenwood, Pamela

2014-06-01

We examined whether a gene known to influence dopamine availability in the prefrontal cortex is associated with individual differences in learning a supervisory control task. Methods are needed for selection and training of human operators who can effectively supervise multiple unmanned vehicles (UVs). Compared to the valine (Val) allele, the methionine (Met) allele of the COMT gene has been linked to superior executive function, but it is not known whether it is associated with training-related effects in multi-UV supervisory control performance. Ninety-nine healthy adults were genotyped for the COMT Val158Met single nucleotide polymorphism (rs4680) and divided into Met/Met, Val/Met, and Val/Val groups. Participants supervised six UVs in an air defense mission requiring them to attack incoming enemy aircraft and protect a no-fly zone from intruders in conditions of low and high task load (numbers of enemy aircraft). Training effects were examined across four blocks of trials in each task load condition. Compared to the Val/Met and Val/Val groups, Met/Met individuals exhibited a greater increase in enemy targets destroyed and greater reduction in enemy red zone incursions across training blocks. Individuals with the COMT Met/Met genotype can acquire skill in executive function tasks, such as multi-UV supervisory control, to a higher level and/or faster than other genotype groups. Potential applications of this research include the development of individualized training methods for operators of multi-UV systems and selecting personnel for complex supervisory control tasks.

Association between Val66Met brain-derived neurotrophic factor (BDNF) gene polymorphism and post-treatment relapse in alcohol dependence.

PubMed

Wojnar, Marcin; Brower, Kirk J; Strobbe, Stephen; Ilgen, Mark; Matsumoto, Halina; Nowosad, Izabela; Sliwerska, Elzbieta; Burmeister, Margit

2009-04-01

The purpose of this study was to examine relationships between genetic markers of central serotonin (5-HT) and dopamine function, and risk for post-treatment relapse, in a sample of alcohol-dependent patients. The study included 154 patients from addiction treatment programs in Poland, who met DSM-IV criteria for alcohol dependence. After assessing demographics, severity of alcohol use, suicidality, impulsivity, depression, hopelessness, and severity of alcohol use at baseline, patients were followed for approximately 1 year to evaluate treatment outcomes. Genetic polymorphisms in several genes (TPH2, SLC6A4, HTR1A, HTR2A, COMT, and BDNF) were tested as predictors of relapse (defined as any drinking during follow-up) while controlling for baseline measures. Of 154 eligible patients, 123 (80%) completed follow-up and 48% (n = 59) of these individuals relapsed. Patients with the Val allele in the Val66Met BDNF polymorphism and the Met allele in the Val158Met COMT polymorphism were more likely to relapse. Only the BDNF Val/Val genotype predicted post-treatment relapse [odds ratio (OR) = 2.62; p = 0.019], and time to relapse (OR = 2.57; p = 0.002), after adjusting for baseline measures and other significant genetic markers. When the analysis was restricted to patients with a family history of alcohol dependence (n = 73), the associations between the BDNF Val/Val genotype and relapse (OR = 5.76, p = 0.0045) and time to relapse (hazard ratio = 4.93, p = 0.001) were even stronger. The Val66Met BDNF gene polymorphism was associated with a higher risk and earlier occurrence of relapse among patients treated for alcohol dependence. The study suggests a relationship between genetic markers and treatment outcomes in alcohol dependence. Because a large number of statistical tests were conducted for this study and the literature on genetics and relapse is so novel, the results should be considered as hypothesis generating and need to be replicated in independent studies.

Association between Val66Met Brain-Derived Neurotrophic Factor (BDNF) Gene Polymorphism and Post-Treatment Relapse in Alcohol Dependence

PubMed Central

Wojnar, Marcin; Brower, Kirk J.; Strobbe, Stephen; Ilgen, Mark; Matsumoto, Halina; Nowosad, Izabela; Sliwerska, Elzbieta; Burmeister, Margit

2009-01-01

Background The purpose of this study was to examine relationships between genetic markers of central serotonin and dopamine function, and risk for post-treatment relapse, in a sample of alcohol-dependent patients. Methods The study included 154 patients from addiction treatment programs in Poland, who met DSM-IV criteria for alcohol dependence. After assessing demographics, severity of alcohol use, suicidality, impulsivity, depression, hopelessness, and severity of alcohol use at baseline, patients were followed for approximately one year to evaluate treatment outcomes. Genetic polymorphisms in several genes (TPH2, SLC6A4, HTR1A, HTR2A, COMT, BDNF) were tested as predictors of relapse (defined as any drinking during follow-up) while controlling for baseline measures. Results Of 154 eligible patients, 123 (80%) completed follow-up and 48% (n = 59) of these individuals relapsed. Patients with the Val allele in the Val66Met BDNF polymorphism and the Met allele in the Val158Met COMT polymorphism were more likely to relapse. Only the BDNF Val/Val genotype predicted post-treatment relapse (OR = 2.62; p = 0.019), and time to relapse (OR = 2.57; p = 0.002), after adjusting for baseline measures and other significant genetic markers. When the analysis was restricted to patients with a family history of alcohol dependence (n = 73), the associations between the BDNF Val/Val genotype and relapse (OR = 5.76, p = 0.0045) and time to relapse (HR = 4.93, p = 0.001) were even stronger. Conclusions The Val66Met BDNF gene polymorphism was associated with a higher risk and earlier occurrence of relapse among patients treated for alcohol dependence. The study suggests a relationship between genetic markers and treatment outcomes in alcohol dependence. Because a large number of statistical tests were conducted for this study and the literature on genetics and relapse is so novel, the results should be considered as hypothesis generating and need to be replicated in independent studies. PMID:19170664

Clinical and genetic factors associated with suicide in mood disorder patients.

PubMed

Antypa, Niki; Souery, Daniel; Tomasini, Mario; Albani, Diego; Fusco, Federica; Mendlewicz, Julien; Serretti, Alessandro

2016-03-01

Suicidality is a continuum ranging from ideation to attempted and completed suicide, with a complex etiology involving both genetic heritability and environmental factors. The majority of suicide events occur in the context of psychiatric conditions, preeminently major depression and bipolar disorder. The present study investigates clinical factors associated with suicide in a sample of 553 mood disorder patients, recruited within the 'Psy Pluriel' center, Centre Européen de Psychologie Médicale, and the Department of Psychiatry of Erasme Hospital (Brussels). Furthermore, genetic association analyses examining polymorphisms within COMT, BDNF, MAPK1 and CREB1 genes were performed in a subsample of 259 bipolar patients. The presence or absence of a previous suicide attempt and of current suicide risk were assessed. A positive association with suicide attempt was reported for younger patients, females, lower educated, smokers, those with higher scores on depressive symptoms and higher functional disability and those with anxiety comorbidity and familial history of suicidality in first- and second-degree relatives. Anxiety disorder comorbidity was the stronger predictor of current suicide risk. No associations were found with polymorphisms within COMT and BDNF genes, whereas significant associations were found with variations in rs13515 (MAPK1) and rs6740584 (CREB1) polymorphisms. From a clinical perspective, our study proposes several clinical characteristics, such as increased depressive symptomatology, anxiety comorbidity, functional disability and family history of suicidality, as correlates associated with suicide. Genetic risk variants in MAPK1 and CREB1 genes might be involved in a dysregulation of inflammatory and neuroplasticity pathways and are worthy of future investigation.

COMT Val158Met Genotype Selectively Alters Prefrontal [18F]Fallypride Displacement and Subjective Feelings of Stress in Response to a Psychosocial Stress Challenge

PubMed Central

Lataster, Johan; Ceccarini, Jenny; Kenis, Gunther; Booij, Linda; Pruessner, Jens; Van Laere, Koen; van Winkel, Ruud; van Os, Jim; Myin-Germeys, Inez

2013-01-01

Catechol-O-methyltransferase (COMT) plays an essential role in degradation of extracellular dopamine in prefrontal regions of the brain. Although a polymorphism in this gene, COMT Val158Met, affects human behavior in response to stress little is known about its effect on dopaminergic activity associated with the human stress response, which may be of interest for stress-related psychiatric disorders such as psychosis. We aimed to investigate the effect of variations in COMT genotype on in vivo measures of stress-induced prefrontal cortex (PFC) dopaminergic processing and subjective stress responses. A combined sample of healthy controls and healthy first-degree relatives of psychosis patients (n = 26) were subjected to an [18F]fallypride Positron Emission Tomography scan. Psychosocial stress during the scan was induced using the Montreal Imaging Stress Task and subjective stress was assessed every 12 minutes. Parametric t-maps, generated using the linear extension of the simplified reference region model, revealed an effect of COMT genotype on the spatial extent of [18F]fallypride displacement. Detected effects of exposure to psychosocial stress were unilateral and remained restricted to the left superior and right inferior frontal gyrus, with Met-hetero- and homozygotes showing less [18F]fallypride displacement than Val-homozygotes. Additionally, Met-hetero- and homozygotes experienced larger subjective stress responses than Val-homozygotes. The direction of the effects remained the same when the data was analyzed separately for controls and first-degree relatives. The human stress response may be mediated in part by COMT-dependent dopaminergic PFC activity, providing speculation for the neurobiology underlying COMT-dependent differences in human behaviour following stress. Implications of these results for stress-related psychopathology and models of dopaminergic functioning are discussed. PMID:23799032

COMT Val158Met genotype selectively alters prefrontal [18F]fallypride displacement and subjective feelings of stress in response to a psychosocial stress challenge.

PubMed

Hernaus, Dennis; Collip, Dina; Lataster, Johan; Ceccarini, Jenny; Kenis, Gunther; Booij, Linda; Pruessner, Jens; Van Laere, Koen; van Winkel, Ruud; van Os, Jim; Myin-Germeys, Inez

2013-01-01

Catechol-O-methyltransferase (COMT) plays an essential role in degradation of extracellular dopamine in prefrontal regions of the brain. Although a polymorphism in this gene, COMT Val(158)Met, affects human behavior in response to stress little is known about its effect on dopaminergic activity associated with the human stress response, which may be of interest for stress-related psychiatric disorders such as psychosis. We aimed to investigate the effect of variations in COMT genotype on in vivo measures of stress-induced prefrontal cortex (PFC) dopaminergic processing and subjective stress responses. A combined sample of healthy controls and healthy first-degree relatives of psychosis patients (n = 26) were subjected to an [(18)F]fallypride Positron Emission Tomography scan. Psychosocial stress during the scan was induced using the Montreal Imaging Stress Task and subjective stress was assessed every 12 minutes. Parametric t-maps, generated using the linear extension of the simplified reference region model, revealed an effect of COMT genotype on the spatial extent of [(18)F]fallypride displacement. Detected effects of exposure to psychosocial stress were unilateral and remained restricted to the left superior and right inferior frontal gyrus, with Met-hetero- and homozygotes showing less [(18)F]fallypride displacement than Val-homozygotes. Additionally, Met-hetero- and homozygotes experienced larger subjective stress responses than Val-homozygotes. The direction of the effects remained the same when the data was analyzed separately for controls and first-degree relatives. The human stress response may be mediated in part by COMT-dependent dopaminergic PFC activity, providing speculation for the neurobiology underlying COMT-dependent differences in human behaviour following stress. Implications of these results for stress-related psychopathology and models of dopaminergic functioning are discussed.

Identifying new susceptibility genes on dopaminergic and serotonergic pathways for the framing effect in decision-making.

PubMed

Gao, Xiaoxue; Liu, Jinting; Gong, Pingyuan; Wang, Junhui; Fang, Wan; Yan, Hongming; Zhu, Lusha; Zhou, Xiaolin

2017-09-01

The framing effect refers the tendency to be risk-averse when options are presented positively but be risk-seeking when the same options are presented negatively during decision-making. This effect has been found to be modulated by the serotonin transporter gene (SLC6A4) and the catechol-o-methyltransferase gene (COMT) polymorphisms, which are on the dopaminergic and serotonergic pathways and which are associated with affective processing. The current study aimed to identify new genetic variations of genes on dopaminergic and serotonergic pathways that may contribute to individual differences in the susceptibility to framing. Using genome-wide association data and the gene-based principal components regression method, we examined genetic variations of 26 genes on the pathways in 1317 Chinese Han participants. Consistent with previous studies, we found that the genetic variations of the SLC6A4 gene and the COMT gene were associated with the framing effect. More importantly, we demonstrated that the genetic variations of the aromatic-L-amino-acid decarboxylase (DDC) gene, which is involved in the synthesis of both dopamine and serotonin, contributed to individual differences in the susceptibility to framing. Our findings shed light on the understanding of the genetic basis of affective decision-making. © The Author (2017). Published by Oxford University Press.

Identifying new susceptibility genes on dopaminergic and serotonergic pathways for the framing effect in decision-making

PubMed Central

Gao, Xiaoxue; Liu, Jinting; Gong, Pingyuan; Wang, Junhui; Fang, Wan; Yan, Hongming; Zhu, Lusha

2017-01-01

Abstract The framing effect refers the tendency to be risk-averse when options are presented positively but be risk-seeking when the same options are presented negatively during decision-making. This effect has been found to be modulated by the serotonin transporter gene (SLC6A4) and the catechol-o-methyltransferase gene (COMT) polymorphisms, which are on the dopaminergic and serotonergic pathways and which are associated with affective processing. The current study aimed to identify new genetic variations of genes on dopaminergic and serotonergic pathways that may contribute to individual differences in the susceptibility to framing. Using genome-wide association data and the gene-based principal components regression method, we examined genetic variations of 26 genes on the pathways in 1317 Chinese Han participants. Consistent with previous studies, we found that the genetic variations of the SLC6A4 gene and the COMT gene were associated with the framing effect. More importantly, we demonstrated that the genetic variations of the aromatic-L-amino-acid decarboxylase (DDC) gene, which is involved in the synthesis of both dopamine and serotonin, contributed to individual differences in the susceptibility to framing. Our findings shed light on the understanding of the genetic basis of affective decision-making. PMID:28431168

The COMT Val/Met polymorphism modulates effects of tDCS on response inhibition.

PubMed

Nieratschker, Vanessa; Kiefer, Christoph; Giel, Katrin; Krüger, Rejko; Plewnia, Christian

2015-01-01

Transcranial direct current stimulation (tDCS) is increasingly discussed as a new option to support the cognitive rehabilitation in neuropsychiatric disorders. However, the therapeutic impact of tDCS is limited by high inter-individual variability. Genetic factors most likely contribute to this variability by modulating the effects of tDCS. We aimed to investigate the influence of the COMT Val(108/158)Met polymorphism on cathodal tDCS effects on executive functioning. Cathodal tDCS was applied to the left dorsolateral prefrontal cortex (dlPFC) during the performance of a parametric Go/No-Go test. We demonstrate an impairing effect of cathodal tDCS to the dlPFC on response inhibition. This effect was only found in individuals homozygous for the Val-allele of the COMT Val(108/158)Met polymorphism. No effects of stimulation on executive functions in Met-allele carriers were detected. Our data indicate that i) cathodal, excitability reducing tDCS, interferes with inhibitory cognitive control, ii) the left dlPFC is critically involved in the neuronal network underlying the control of response inhibition, and iii) the COMT Val(108/158)Met polymorphism modulates the impact of cathodal tDCS on inhibitory control. Together with our previous finding that anodal tDCS selectively impairs set-shifting abilities in COMT Met/Met homozygous individuals, these results indicate that genetic factors modulate effects of tDCS on cognitive performance. Therefore, future tDCS research should account for genetic variability in the design and analysis of neurocognitive as well as therapeutic applications to reduce the variability of results and facilitate individualized neurostimulation approaches. Copyright © 2015 Elsevier Inc. All rights reserved.

Association of the Catechol-O-Methyltransferase (COMT) Val158Met Polymorphism and Anxiety-Related Traits: A Meta-Analysis

PubMed Central

Lee, Lewina O.; Prescott, Carol A.

2014-01-01

Objectives The main goals of this study were: (i) to examine genotypic association of the COMT val158met polymorphism with anxiety-related traits via a meta-analysis; (ii) to examine sex and ethnicity as moderators of the association, and (iii) to evaluate whether the association differed by particular anxiety traits. Methods Association studies of the COMT val18met polymorphism and anxiety traits were identified from the PubMed or PsycInfo databases, conference abstracts and listserv postings. Exclusion criteria were: (a) pediatric samples, (b) exclusively clinical samples, and (c) samples selected for a non-anxiety phenotype. Standardized mean differences in anxiety between genotypes were aggregated to produce mean effect sizes across all available samples, and for subgroups stratified by sex and ethnicity (Caucasians vs. Asians). Construct-specific analysis was conducted to evaluate the association of COMT with neuroticism, harm avoidance, and behavioral inhibition. Results Twenty seven eligible studies (N=15,979) with available data were identified. Overall findings indicate sex-specific and ethnic-specific effects: Val homozygotes had higher neuroticism than Met homozygotes in studies of Caucasian males ( ES¯=0.13, 95%CI: 0.02 – 0.25, p = 0.03), and higher harm avoidance in studies of Asian males ( ES¯=0.43, 95%CI: 0.14 – 0.72, p = 0.004). No significant associations were found in women and effect sizes were diminished when studies were aggregated across ethnicity or anxiety traits. Conclusions: This meta-analysis provides evidence for sex and ethnicity differences in the association of the COMT val158met polymorphism with anxiety traits. Our findings contribute to current knowledge on the relation between prefrontal dopaminergic transmission and anxiety. PMID:24300663

Child exposure to serious life events, COMT, and aggression: Testing differential susceptibility theory.

PubMed

Hygen, Beate Wold; Belsky, Jay; Stenseng, Frode; Lydersen, Stian; Guzey, Ismail Cuneyt; Wichstrøm, Lars

2015-08-01

Both genetic and environmental factors contribute to individual differences in aggression. Catechol-O-methyltransferase Val158Met (COMT), a common, functional polymorphism, has been implicated in aggression and aggression traits, as have childhood experiences of adversity. It is unknown whether these effects are additive or interactional and, in the case of interaction, whether they conform to a diathesis-stress or differential susceptibility model. We examined Gene × Environment interactions between COMT and serious life events on measures of childhood aggression and contrasted these 2 models. The sample was composed of community children (N = 704); 355 were boys, and the mean age was 54.8 months (SD = 3.0). The children were genotyped for COMT rs4680 and assessed for serious life events and by teacher-rated aggression. Regression analysis showed no main effects of COMT and serious life events on aggression. However, a significant interactive effect of childhood serious life events and COMT genotype was observed: Children who had faced many serious life events and were Val homozygotes exhibited more aggression (p = .02) than did their Met-carrying counterparts. Notably, in the absence of serious life events, Val homozygotes displayed significantly lower aggression scores than did Met carriers (p = .03). When tested, this constellation of findings conformed to the differential susceptibility hypothesis: In this case, Val homozygotes are more malleable to the effect of serious life events on aggression and not simply more vulnerable to the negative effect of having experienced many serious life events. (c) 2015 APA, all rights reserved).

Variation in the dopamine D2 receptor gene plays a key role in human pain and its modulation by transcranial magnetic stimulation.

PubMed

Jääskeläinen, Satu K; Lindholm, Pauliina; Valmunen, Tanja; Pesonen, Ullamari; Taiminen, Tero; Virtanen, Arja; Lamusuo, Salla; Forssell, Heli; Hagelberg, Nora; Hietala, Jarmo; Pertovaara, Antti

2014-10-01

We tested whether variation of the dopamine D2 receptor (DRD2) gene contributes to individual differences in thermal pain sensitivity and analgesic efficacy of repetitive transcranial magnetic stimulation (rTMS) in healthy subjects (n=29) or susceptibility to neuropathic pain in patients with neurophysiologically confirmed diagnosis (n=16). Thermal sensitivity of healthy subjects was assessed before and after navigated rTMS provided to the S1/M1 cortex. All subjects were genotyped for the DRD2 gene 957C>T and catechol-O-methyltransferase (COMT) protein Val158Met polymorphisms. In healthy subjects, 957C>T influenced both innocuous and noxious thermal detection thresholds that were lowest in 957TT homozygotes (P values from .0277 to .0462). rTMS to S1 cortex had analgesic effect only in 957TT homozygote genotype (P=.0086). In patients, prevalence of 957TT homozygote genotype was higher than in a healthy Finnish population (50% vs 27%; P=.0191). Patients with 957TT genotype reported more severe pain than patients with other genotypes (P=.0351). COMT Val158Met polymorphism was not independently associated with the studied variables. Genetic regulation of DRD2 function by 957C>T polymorphism thus seems to influence thermal and pain sensitivity, its modulation by rTMS, and susceptibility to neuropathic pain. This indicates a central role for the dopamine system and DRD2 in pain and analgesia. This may have clinical implications regarding individualized selection of patients for rTMS treatment and assessment of risks for neuropathic pain. Copyright © 2014 International Association for the Study of Pain. Published by Elsevier B.V. All rights reserved.

Epistasis between dopamine regulating genes identifies a nonlinear response of the human hippocampus during memory tasks.

PubMed

Bertolino, Alessandro; Di Giorgio, Annabella; Blasi, Giuseppe; Sambataro, Fabio; Caforio, Grazia; Sinibaldi, Lorenzo; Latorre, Valeria; Rampino, Antonio; Taurisano, Paolo; Fazio, Leonardo; Romano, Raffaella; Douzgou, Sofia; Popolizio, Teresa; Kolachana, Bhaskar; Nardini, Marcello; Weinberger, Daniel R; Dallapiccola, Bruno

2008-08-01

Dopamine modulation of neuronal activity in prefrontal cortex maps to an inverted U-curve. Dopamine is also an important factor in regulation of hippocampal mediated memory processing. Here, we investigated the effect of genetic variation of dopamine inactivation via catechol-O-methyltransferase (COMT) and the dopamine transporter (DAT) on hippocampal activity in healthy humans during different memory conditions. Using blood oxygenation level-dependent (BOLD) functional magnetic resonance imaging (fMRI) in 82 subjects matched for a series of demographic and genetic variables, we studied the effect of the COMT valine (Val)(158)methionine (Met) and the DAT 3' variable number tandem repeat (VNTR) polymorphisms on function of the hippocampus during encoding of recognition memory and during working memory. Our results consistently demonstrated a double dissociation so that DAT 9-repeat carrier alleles modulated activity in the hippocampus in the exact opposite direction of DAT 10/10-repeat alleles based on COMT Val(158)Met genotype during different memory conditions. Similar results were evident in ventrolateral and dorsolateral prefrontal cortex. These findings suggest that genetically determined dopamine signaling during memory processing maps to a nonlinear relationship also in the hippocampus. Our data also demonstrate in human brain epistasis of two genes implicated in dopamine signaling on brain activity during different memory conditions.

Modulation of the COMT Val(158)Met polymorphism on resting-state EEG power.

PubMed

Solís-Ortiz, Silvia; Pérez-Luque, Elva; Gutiérrez-Muñoz, Mayra

2015-01-01

The catechol-O-methyltransferase (COMT) Val(158)Met polymorphism impacts cortical dopamine (DA) levels and may influence cortical electrical activity in the human brain. This study investigated whether COMT genotype influences resting-state electroencephalogram (EEG) power in the frontal, parietal and midline regions in healthy volunteers. EEG recordings were conducted in the resting-state in 13 postmenopausal healthy woman carriers of the Val/Val genotype and 11 with the Met/Met genotype. The resting EEG spectral absolute power in the frontal (F3, F4, F7, F8, FC3 and FC4), parietal (CP3, CP4, P3 and P4) and midline (Fz, FCz, Cz, CPz, Pz and Oz) was analyzed during the eyes-open and eyes-closed conditions. The frequency bands considered were the delta, theta, alpha1, alpha2, beta1 and beta2. EEG data of the Val/Val and Met/Met genotypes, brain regions and conditions were analyzed using a general linear model analysis. In the individuals with the Met/Met genotype, delta activity was increased in the eyes-closed condition, theta activity was increased in the eyes-closed and in the eyes-open conditions, and alpha1 band, alpha2 band and beta1band activity was increased in the eyes-closed condition. A significant interaction between COMT genotypes and spectral bands was observed. Met homozygote individuals exhibited more delta, theta and beta1 activity than individuals with the Val/Val genotype. No significant interaction between COMT genotypes and the resting-state EEG regional power and conditions were observed for the three brain regions studied. Our findings indicate that the COMT Val(158)Met polymorphism does not directly impact resting-state EEG regional power, but instead suggest that COMT genotype can modulate resting-state EEG spectral power in postmenopausal healthy women.

Modulation of the COMT Val158Met polymorphism on resting-state EEG power

PubMed Central

Solís-Ortiz, Silvia; Pérez-Luque, Elva; Gutiérrez-Muñoz, Mayra

2015-01-01

The catechol-O-methyltransferase (COMT) Val158Met polymorphism impacts cortical dopamine (DA) levels and may influence cortical electrical activity in the human brain. This study investigated whether COMT genotype influences resting-state electroencephalogram (EEG) power in the frontal, parietal and midline regions in healthy volunteers. EEG recordings were conducted in the resting-state in 13 postmenopausal healthy woman carriers of the Val/Val genotype and 11 with the Met/Met genotype. The resting EEG spectral absolute power in the frontal (F3, F4, F7, F8, FC3 and FC4), parietal (CP3, CP4, P3 and P4) and midline (Fz, FCz, Cz, CPz, Pz and Oz) was analyzed during the eyes-open and eyes-closed conditions. The frequency bands considered were the delta, theta, alpha1, alpha2, beta1 and beta2. EEG data of the Val/Val and Met/Met genotypes, brain regions and conditions were analyzed using a general linear model analysis. In the individuals with the Met/Met genotype, delta activity was increased in the eyes-closed condition, theta activity was increased in the eyes-closed and in the eyes-open conditions, and alpha1 band, alpha2 band and beta1band activity was increased in the eyes-closed condition. A significant interaction between COMT genotypes and spectral bands was observed. Met homozygote individuals exhibited more delta, theta and beta1 activity than individuals with the Val/Val genotype. No significant interaction between COMT genotypes and the resting-state EEG regional power and conditions were observed for the three brain regions studied. Our findings indicate that the COMT Val158Met polymorphism does not directly impact resting-state EEG regional power, but instead suggest that COMT genotype can modulate resting-state EEG spectral power in postmenopausal healthy women. PMID:25883560

COMT Val158Met polymorphism is associated with post-traumatic stress disorder and functional outcome following mild traumatic brain injury

PubMed Central

Winkler, Ethan A.; Yue, John K.; Ferguson, Adam R.; Temkin, Nancy R.; Stein, Murray B.; Barber, Jason; Yuh, Esther L.; Sharma, Sourabh; Satris, Gabriela G.; McAllister, Thomas W.; Rosand, Jonathan; Sorani, Marco D.; Lingsma, Hester F.; Tarapore, Phiroz E.; Burchard, Esteban G.; Hu, Donglei; Eng, Celeste; Wang, Kevin K.W.; Mukherjee, Pratik; Okonkwo, David O.; Diaz-Arrastia, Ramon; Manley, Geoffrey T.

2017-01-01

Mild traumatic brain injury (mTBI) results in variable clinical trajectories and outcomes. The source of variability remains unclear, but may involve genetic variations, such as single nucleotide polymorphisms (SNPs). A SNP in catechol-o-methyltransferase (COMT) is suggested to influence development of post-traumatic stress disorder (PTSD), but its role in TBI remains unclear. Here, we utilize the Transforming Research and Clinical Knowledge in Traumatic Brain Injury Pilot (TRACK-TBI Pilot) study to investigate whether the COMT Val158Met polymorphism is associated with PTSD and global functional outcome as measured by the PTSD Checklist – Civilian Version and Glasgow Outcome Scale Extended (GOSE), respectively. Results in 93 predominately Caucasian subjects with mTBI show that the COMT Met158 allele is associated with lower incidence of PTSD (univariate odds ratio (OR) of 0.25, 95% CI [0.09–0.69]) and higher GOSE scores (univariate OR 2.87, 95% CI [1.20–6.86]) 6-months following injury. The COMT Val158Met genotype and PTSD association persists after controlling for race (multivariable OR of 0.29, 95% CI [0.10–0.83]) and pre-existing psychiatric disorders/substance abuse (multivariable OR of 0.32, 95% CI [0.11–0.97]). PTSD emerged as a strong predictor of poorer outcome on GOSE (multivariable OR 0.09, 95% CI [0.03–0.26]), which persists after controlling for age, GCS, and race. When accounting for PTSD in multivariable analysis, the association of COMT genotype and GOSE did not remain significant (multivariable OR 1.73, 95% CI [0.69–4.35]). Whether COMT genotype indirectly influences global functional outcome through PTSD remains to be determined and larger studies in more diverse populations are needed to confirm these findings. PMID:27769642

COMT Val158Met polymorphism is associated with post-traumatic stress disorder and functional outcome following mild traumatic brain injury.

PubMed

Winkler, Ethan A; Yue, John K; Ferguson, Adam R; Temkin, Nancy R; Stein, Murray B; Barber, Jason; Yuh, Esther L; Sharma, Sourabh; Satris, Gabriela G; McAllister, Thomas W; Rosand, Jonathan; Sorani, Marco D; Lingsma, Hester F; Tarapore, Phiroz E; Burchard, Esteban G; Hu, Donglei; Eng, Celeste; Wang, Kevin K W; Mukherjee, Pratik; Okonkwo, David O; Diaz-Arrastia, Ramon; Manley, Geoffrey T

2017-01-01

Mild traumatic brain injury (mTBI) results in variable clinical trajectories and outcomes. The source of variability remains unclear, but may involve genetic variations, such as single nucleotide polymorphisms (SNPs). A SNP in catechol-o-methyltransferase (COMT) is suggested to influence development of post-traumatic stress disorder (PTSD), but its role in TBI remains unclear. Here, we utilize the Transforming Research and Clinical Knowledge in Traumatic Brain Injury Pilot (TRACK-TBI Pilot) study to investigate whether the COMT Val 158 Met polymorphism is associated with PTSD and global functional outcome as measured by the PTSD Checklist - Civilian Version and Glasgow Outcome Scale Extended (GOSE), respectively. Results in 93 predominately Caucasian subjects with mTBI show that the COMT Met 158 allele is associated with lower incidence of PTSD (univariate odds ratio (OR) of 0.25, 95% CI [0.09-0.69]) and higher GOSE scores (univariate OR 2.87, 95% CI [1.20-6.86]) 6-months following injury. The COMT Val 158 Met genotype and PTSD association persists after controlling for race (multivariable OR of 0.29, 95% CI [0.10-0.83]) and pre-existing psychiatric disorders/substance abuse (multivariable OR of 0.32, 95% CI [0.11-0.97]). PTSD emerged as a strong predictor of poorer outcome on GOSE (multivariable OR 0.09, 95% CI [0.03-0.26]), which persists after controlling for age, GCS, and race. When accounting for PTSD in multivariable analysis, the association of COMT genotype and GOSE did not remain significant (multivariable OR 1.73, 95% CI [0.69-4.35]). Whether COMT genotype indirectly influences global functional outcome through PTSD remains to be determined and larger studies in more diverse populations are needed to confirm these findings. Copyright © 2016 Elsevier Ltd. All rights reserved.

The effect of COMT Val158 Met genotype on decision-making and preliminary findings on its interaction with the 5-HTTLPR in healthy females.

PubMed

van den Bos, Ruud; Homberg, Judith; Gijsbers, Ellen; den Heijer, Esther; Cuppen, Edwin

2009-02-01

Poor decision-making is inherent to several psychiatric conditions for which a genetic basis may exist. We previously showed that healthy female volunteers homozygous for the short allele (s/s) of the serotonin transporter length polymorphic region (5-HTTLPR) chose more often cards from disadvantageous decks in the Iowa Gambling Task (IGT), which measures decision-making, than long (l) allele carriers. The 5-HTTLPR and catechol-O-methyltransferase (COMT) Val(158) Met polymorphism affect the same set of neuronal structures. Therefore, we explored the effect of the (COMT) Val(158) Met polymorphism on IGT performance and its interaction with the 5-HTTLPR in the same subjects in this study. We observed that subjects homozygous for methionine (Met/Met) chose more disadvantageously than subjects homozygous for valine (Val/Val). s/s-Met/Met-subjects appeared to show the poorest IGT performance of all possible combinations of 5-HTTLPR and COMT allelic variants. Using the Expectancy-Valence model, no differences were found for the three different 5-HTTLPR or COMT genotypes regarding (i) attention to wins versus losses, (ii) updating rate, or (iii) response consistency. However, subjects with at least one Met-allele were paying more attention to wins than subjects with no Met-alleles. We discuss whether a common neuronal mechanism relates to s- and Met-allele-related deficits in updating and/or processing of choice outcome to guide subsequent choices in this gamble-based test.

Attention Deficit Hyperactivity Disorder comorbid oppositional defiant disorder and its predominately inattentive type: evidence for an association with COMT but not MAOA in a Chinese sample.

PubMed

Qian, Qiu-Jin; Liu, Jin; Wang, Yu-Feng; Yang, Li; Guan, Li-Li; Faraone, Stephen V

2009-02-19

There are three childhood disruptive behavior disorders (DBDs), attention deficit hyperactivity disorder (ADHD), oppositional defiant disorder (ODD), and conduct disorder (CD). The most common comorbid disorder in ADHD is ODD. DSM-IV describes three ADHD subtypes: predominantly inattentive type (ADHD-IA), predominantly hyperactive-impulsive type (ADHD-HI), and combined type (ADHD-C). Prior work suggests that specific candidate genes are associated with specific subtypes of ADHD in China. Our previous association studies between ADHD and functional polymorphisms of COMT and MAOA, consistently showed the low transcriptional activity alleles were preferentially transmitted to ADHD-IA boys. Thus, the goal of the present study is to test the hypothesis that COMT Val158Met and MAOA-uVNTR jointly contribute to the ODD phenotype among Chinese ADHD boys. 171 Chinese boys between 6 and 17.5 years old (mean = 10.3, SD = 2.6) with complete COMT val158met and MAOA-uVNTR genotyping information were studied. We used logistic regression with genotypes as independent variables and the binary phenotype as the dependent variable. We used p < 0.05 as the level of nominal statistical significance. Bonferroni correction procedures were used to adjust for multiple comparisons. Our results highlight the potential etiologic role of COMT in the ADHD with comorbid ODD and its predominately inattentive type in male Chinese subjects. ADHD with comorbid ODD was associated with homozygosity of the high-activity Val allele, while the predominantly inattentive ADHD subtype was associated with the low-activity Met allele. We found no evidence of association between the MAOA-uVNTR variant and ADHD with comorbid ODD or the ADHD-IA subtype. Our study of attention deficit hyperactivity disorder comorbid oppositional defiant disorder and its predominately inattentive type highlights the potential etiologic role of COMT for ADHD children in China. But we failed to observe an interaction between COMT and MAOA, which suggests that epistasis between COMT and MAOA genes does not influence the phenotype of ADHD-IA with comorbid ODD in a clinical sample of Chinese male subjects. To confirm our findings further studies with a larger number of subjects and healthy controls are needed.

The association between the oxytocin receptor gene (OXTR) and hypnotizability.

PubMed

Bryant, Richard A; Hung, Lynette; Dobson-Stone, Carol; Schofield, Peter R

2013-10-01

Hypnosis has puzzled scientists for centuries, and particularly the reason why some people are prone to engaging in suggested experiences discordant with external reality. Absorption in internal experience is one key component of the hypnotic response. The neuropeptide oxytocin has been posited to heighten sensitivity to external cues, and it is possible that individual differences in oxytocin-related capacity to engage in external or internal experiences influences hypnotic response. To test this proposal, 185 Caucasian individuals provided saliva samples for analysis of polymorphisms in the oxytocin receptor gene, COMT, and independently completed standardized measures of hypnotizability and absorption. Participants with the GG genotype at rs53576 were characterized by lower hypnotizability and absorption scores than those with the A allele; there was no association between hyponotizability and COMT. These findings provide initial evidence that the capacity to respond to suggestions for altered internal experience is influenced by the oxytocin receptor gene, and is consistent with evidence that oxytocin plays an important role in modulating the extent to which people engage with external versus internal experiences. Copyright © 2013 Elsevier Ltd. All rights reserved.

Is less really more: Does a prefrontal efficiency genotype actually confer better performance when working memory becomes difficult?

PubMed

Ihne, Jessica L; Gallagher, Natalie M; Sullivan, Marie; Callicott, Joseph H; Green, Adam E

2016-01-01

Perhaps the most widely studied effect to emerge from the combination of neuroimaging and human genetics is the association of the COMT-Val(108/158)Met polymorphism with prefrontal activity during working memory. COMT-Val is a putative risk factor in schizophrenia, which is characterized by disordered prefrontal function. Work in healthy populations has sought to characterize mechanisms by which the valine (Val) allele may lead to disadvantaged prefrontal cognition. Lower activity in methionine (Met) carriers has been interpreted as advantageous neural efficiency. Notably, however, studies reporting COMT effects on neural efficiency have generally not reported working memory performance effects. Those studies have employed relatively low/easy working memory loads. Higher loads are known to elicit individual differences in working memory performance that are not visible at lower loads. If COMT-Met confers greater neural efficiency when working memory is easy, a reasonable prediction is that Met carriers will be better able to cope with increasing demand for neural resources when working memory becomes difficult. To our knowledge, this prediction has thus far gone untested. Here, we tested performance on three working memory tasks. Performance on each task was measured at multiple levels of load/difficulty, including loads more demanding than those used in prior studies. We found no genotype-by-load interactions or main effects of COMT genotype on accuracy or reaction time. Indeed, even testing for performance differences at each load of each task failed to find a single significant effect of COMT genotype. Thus, even if COMT genotype has the effects on prefrontal efficiency that prior work has suggested, such effects may not directly impact high-load working memory ability. The present findings accord with previous evidence that behavioral effects of COMT are small or nonexistent and, more broadly, with a growing consensus that substantial effects on phenotype will not emerge from candidate gene studies. Copyright © 2015 Elsevier Ltd. All rights reserved.

The Mediating Effect of Prefrontal Asymmetry on the Relationship between the COMT Val158Met SNP and Trait Consummatory Positive Affect

PubMed Central

Katz, Andrea C.; Sarapas, Casey; Bishop, Jeffrey R.; Patel, Shitalben R.; Shankman, Stewart A.

2014-01-01

The Val158Met rs4680 polymorphism in the COMT gene regulates dopamine catabolism in the prefrontal cortex (PFC). Dopamine’s involvement in reward experience suggests those with the Met variant may exhibit trait-level sensitivity to reward due to more post-synaptic dopamine in the PFC. A physiological mediator of this association may be greater relative left asymmetry in the PFC, a putative biomarker for trait positive emotionality. Electroencephalograms of 120 participants were measured during a task that assesses two aspects of reward processing: pre-reward anticipation and post-reward consummatory affect. Participants provided genetics samples and completed the Temporal Experience of Pleasure Scale, which assesses trait-level anticipatory and consummatory positive affect. Met carriers had higher TEPS-Consummatory scores. This effect was mediated by greater relative left activation in the post-reward phase of the task. No effects were observed for the pre-reward phase. Results suggest that frontal asymmetry is an endophenotype between COMT genotype and trait reward responsivity. PMID:25195915

Dopamine Inactivation Efficacy Related to Functional DAT1 and COMT Variants Influences Motor Response Evaluation

PubMed Central

Bender, Stephan; Rellum, Thomas; Freitag, Christine; Resch, Franz; Rietschel, Marcella; Treutlein, Jens; Jennen-Steinmetz, Christine; Brandeis, Daniel; Banaschewski, Tobias; Laucht, Manfred

2012-01-01

Background Dopamine plays an important role in orienting, response anticipation and movement evaluation. Thus, we examined the influence of functional variants related to dopamine inactivation in the dopamine transporter (DAT1) and catechol-O-methyltransferase genes (COMT) on the time-course of motor processing in a contingent negative variation (CNV) task. Methods 64-channel EEG recordings were obtained from 195 healthy adolescents of a community-based sample during a continuous performance task (A-X version). Early and late CNV as well as motor postimperative negative variation were assessed. Adolescents were genotyped for the COMT Val158Met and two DAT1 polymorphisms (variable number tandem repeats in the 3′-untranslated region and in intron 8). Results The results revealed a significant interaction between COMT and DAT1, indicating that COMT exerted stronger effects on lateralized motor post-processing (centro-parietal motor postimperative negative variation) in homozygous carriers of a DAT1 haplotype increasing DAT1 expression. Source analysis showed that the time interval 500–1000 ms after the motor response was specifically affected in contrast to preceding movement anticipation and programming stages, which were not altered. Conclusions Motor slow negative waves allow the genomic imaging of dopamine inactivation effects on cortical motor post-processing during response evaluation. This is the first report to point towards epistatic effects in the motor system during response evaluation, i.e. during the post-processing of an already executed movement rather than during movement programming. PMID:22649558

Brain white matter structure and COMT gene are linked to second-language learning in adults

PubMed Central

Mamiya, Ping C.; Richards, Todd L.; Coe, Bradley P.; Eichler, Evan E.; Kuhl, Patricia K.

2016-01-01

Adult human brains retain the capacity to undergo tissue reorganization during second-language learning. Brain-imaging studies show a relationship between neuroanatomical properties and learning for adults exposed to a second language. However, the role of genetic factors in this relationship has not been investigated. The goal of the current study was twofold: (i) to characterize the relationship between brain white matter fiber-tract properties and second-language immersion using diffusion tensor imaging, and (ii) to determine whether polymorphisms in the catechol-O-methyltransferase (COMT) gene affect the relationship. We recruited incoming Chinese students enrolled in the University of Washington and scanned their brains one time. We measured the diffusion properties of the white matter fiber tracts and correlated them with the number of days each student had been in the immersion program at the time of the brain scan. We found that higher numbers of days in the English immersion program correlated with higher fractional anisotropy and lower radial diffusivity in the right superior longitudinal fasciculus. We show that fractional anisotropy declined once the subjects finished the immersion program. The relationship between brain white matter fiber-tract properties and immersion varied in subjects with different COMT genotypes. Subjects with the Methionine (Met)/Valine (Val) and Val/Val genotypes showed higher fractional anisotropy and lower radial diffusivity during immersion, which reversed immediately after immersion ended, whereas those with the Met/Met genotype did not show these relationships. Statistical modeling revealed that subjects’ grades in the language immersion program were best predicted by fractional anisotropy and COMT genotype. PMID:27298360

Brain white matter structure and COMT gene are linked to second-language learning in adults.

PubMed

Mamiya, Ping C; Richards, Todd L; Coe, Bradley P; Eichler, Evan E; Kuhl, Patricia K

2016-06-28

Adult human brains retain the capacity to undergo tissue reorganization during second-language learning. Brain-imaging studies show a relationship between neuroanatomical properties and learning for adults exposed to a second language. However, the role of genetic factors in this relationship has not been investigated. The goal of the current study was twofold: (i) to characterize the relationship between brain white matter fiber-tract properties and second-language immersion using diffusion tensor imaging, and (ii) to determine whether polymorphisms in the catechol-O-methyltransferase (COMT) gene affect the relationship. We recruited incoming Chinese students enrolled in the University of Washington and scanned their brains one time. We measured the diffusion properties of the white matter fiber tracts and correlated them with the number of days each student had been in the immersion program at the time of the brain scan. We found that higher numbers of days in the English immersion program correlated with higher fractional anisotropy and lower radial diffusivity in the right superior longitudinal fasciculus. We show that fractional anisotropy declined once the subjects finished the immersion program. The relationship between brain white matter fiber-tract properties and immersion varied in subjects with different COMT genotypes. Subjects with the Methionine (Met)/Valine (Val) and Val/Val genotypes showed higher fractional anisotropy and lower radial diffusivity during immersion, which reversed immediately after immersion ended, whereas those with the Met/Met genotype did not show these relationships. Statistical modeling revealed that subjects' grades in the language immersion program were best predicted by fractional anisotropy and COMT genotype.

Dopamine and the Creative Mind: Individual Differences in Creativity Are Predicted by Interactions between Dopamine Genes DAT and COMT.

PubMed

Zabelina, Darya L; Colzato, Lorenza; Beeman, Mark; Hommel, Bernhard

2016-01-01

The dopaminergic (DA) system may be involved in creativity, however results of past studies are mixed. We attempted to clarify this putative relation by considering the mediofrontal and the nigrostriatal DA pathways, uniquely and in combination, and their contribution to two different measures of creativity--an abbreviated version of the Torrance Test of Creative Thinking, assessing divergent thinking, and a real-world creative achievement index. We found that creativity can be predicted from interactions between genetic polymorphisms related to frontal (COMT) and striatal (DAT) DA pathways. Importantly, the Torrance test and the real-world creative achievement index related to different genetic patterns, suggesting that these two measures tap into different aspects of creativity, and depend on distinct, but interacting, DA sub-systems. Specifically, we report that successful performance on the Torrance test is linked with dopaminergic polymorphisms associated with good cognitive flexibility and medium top-down control, or with weak cognitive flexibility and strong top-down control. The latter is particularly true for the originality factor of divergent thinking. High real-world creative achievement, on the other hand, as assessed by the Creative Achievement Questionnaire, is linked with dopaminergic polymorphisms associated with weak cognitive flexibility and weak top-down control. Taken altogether, our findings support the idea that human creativity relies on dopamine, and on the interaction between frontal and striatal dopaminergic pathways in particular. This interaction may help clarify some apparent inconsistencies in the prior literature, especially if the genes and/or creativity measures were analyzed separately.

Dopamine and the Creative Mind: Individual Differences in Creativity Are Predicted by Interactions between Dopamine Genes DAT and COMT

PubMed Central

Zabelina, Darya L.; Colzato, Lorenza; Beeman, Mark; Hommel, Bernhard

2016-01-01

The dopaminergic (DA) system may be involved in creativity, however results of past studies are mixed. We attempted to clarify this putative relation by considering the mediofrontal and the nigrostriatal DA pathways, uniquely and in combination, and their contribution to two different measures of creativity–an abbreviated version of the Torrance Test of Creative Thinking, assessing divergent thinking, and a real-world creative achievement index. We found that creativity can be predicted from interactions between genetic polymorphisms related to frontal (COMT) and striatal (DAT) DA pathways. Importantly, the Torrance test and the real-world creative achievement index related to different genetic patterns, suggesting that these two measures tap into different aspects of creativity, and depend on distinct, but interacting, DA sub-systems. Specifically, we report that successful performance on the Torrance test is linked with dopaminergic polymorphisms associated with good cognitive flexibility and medium top-down control, or with weak cognitive flexibility and strong top-down control. The latter is particularly true for the originality factor of divergent thinking. High real-world creative achievement, on the other hand, as assessed by the Creative Achievement Questionnaire, is linked with dopaminergic polymorphisms associated with weak cognitive flexibility and weak top-down control. Taken altogether, our findings support the idea that human creativity relies on dopamine, and on the interaction between frontal and striatal dopaminergic pathways in particular. This interaction may help clarify some apparent inconsistencies in the prior literature, especially if the genes and/or creativity measures were analyzed separately. PMID:26783754

[The association of polymorphisms in SLC18A1, TPH1 and RELN genes with risk of paranoid schizophrenia].

PubMed

Galaktionova, D Iu; Gareeva, A E; Khusnutdinova, E K; Nasedkina, T V

2014-01-01

We have developed a biochip for the analysis of polymorphisms in candidate genes for schizophrenia: DISC1, RELN, ZNF804A, PLXNA2, COMT, SLC18A41, CACNA1C, ANK3, TPH1, PLAA and SNAP-25. Using biochip the allele and genotype frequencies in 198 patients with schizophrenia and 192 healthy individuals have been obtained. For SLC18A1 polymorphism rs2270641 A>C, the frequencies of A allele (p = 0.007) and AA genotype (p = 0.002) were lower in patients compared with healthy individuals. A significant association was found between AA genotype (p = 0.036) of the TPH1 polymorphism rs1800532 C>A and schizophrenia. The C allele (p = 0.039) of the RELNpolymorphism rs7341475 C>T were lower in patients with schizophrenia compared with healthy individuals in a tatar population. Genotype AA of the TPH1 polymorphism rs1800532 C>A were more frequent in patients with schizophrenia compared with healthy individuals. Ithas been shown that the C allele (p = 0.0001) and GC (p = = 0.0001) genotype of the PLXNA2 polymorphism rs1327175 G>C are associated with the family history in patients with paranoid schizophrenia. The obtained data suggest that SLC18A1, TPH1 and RELN gene polymorphisms are associated with the risk of paranoid schizophrenia.

Imaging oxytocin × dopamine interactions: an epistasis effect of CD38 and COMT gene variants influences the impact of oxytocin on amygdala activation to social stimuli

PubMed Central

Sauer, Carina; Montag, Christian; Reuter, Martin; Kirsch, Peter

2013-01-01

Although oxytocin (OT) has become a major target for the investigation of positive social processes, it can be assumed that it exerts its effects in concert with other neurotransmitters. One candidate for such an interaction is dopamine (DA). For both systems, genetic variants have been identified that influence the availability of the particular substance. A variant of the gene coding for the transmembrane protein CD38 (rs3796863), which is engaged in OT secretion, has been associated with OT plasma level. The common catechol-O-methyltransferase (COMT) val158met polymorphism is known to influence COMT activity and therefore the degradation of DA. The present study aimed to investigate OT × DA interactions in the context of an OT challenge study. Hence, we tested the influence of the above mentioned genetic variants and their interaction on the activation of different brain regions (amygdala, VTA, ventral striatum and fusiform gyrus) during the presentation of social stimuli. In a pharmacological cross-over design 55 participants were investigated under OT and placebo (PLA) by means of fMRI. Brain imaging results revealed no significant effects for VTA or ventral striatum. Regarding the fusiform gyrus, we could not find any effects apart from those already described in Sauer et al. (2012). Analyses of amygdala activation resulted in no gene main effect, no gene × substance interaction but a significant gene × gene × substance interaction. While under PLA the effect of CD38 on bilateral amygdala activation to social stimuli was modulated by the COMT genotype, no such epistasis effect was found under OT. Our results provide evidence for an OT × DA interaction during responses to social stimuli. We postulate that the effect of central OT secretion on amygdala response is modulated by the availability of DA. Therefore, for an understanding of the effect of social hormones on social behavior, interactions of OT with other transmitter systems have to be taken into account. PMID:23554586

Interaction between catechol-O-methyltransferase (COMT) Val158Met genotype and genetic vulnerability to schizophrenia during explicit processing of aversive facial stimuli.

PubMed

Lo Bianco, L; Blasi, G; Taurisano, P; Di Giorgio, A; Ferrante, F; Ursini, G; Fazio, L; Gelao, B; Romano, R; Papazacharias, A; Caforio, G; Sinibaldi, L; Popolizio, T; Bellantuono, C; Bertolino, A

2013-02-01

Emotion dysregulation is a key feature of schizophrenia, a brain disorder strongly associated with genetic risk and aberrant dopamine signalling. Dopamine is inactivated by catechol-O-methyltransferase (COMT), whose gene contains a functional polymorphism (COMT Val158Met) associated with differential activity of the enzyme and with brain physiology of emotion processing. The aim of the present study was to investigate whether genetic risk for schizophrenia and COMT Val158Met genotype interact on brain activity during implicit and explicit emotion processing. A total of 25 patients with schizophrenia, 23 healthy siblings of patients and 24 comparison subjects genotyped for COMT Val158Met underwent functional magnetic resonance imaging during implicit and explicit processing of facial stimuli with negative emotional valence. We found a main effect of diagnosis in the right amygdala, with decreased activity in patients and siblings compared with control subjects. Furthermore, a genotype × diagnosis interaction was found in the left middle frontal gyrus, such that the effect of genetic risk for schizophrenia was evident in the context of the Val/Val genotype only, i.e. the phenotype of reduced activity was present especially in Val/Val patients and siblings. Finally, a complete inversion of the COMT effect between patients and healthy subjects was found in the left striatum during explicit processing. Overall, these results suggest complex interactions between genetically determined dopamine signalling and risk for schizophrenia on brain activity in the prefrontal cortex during emotion processing. On the other hand, the effects in the striatum may represent state-related epiphenomena of the disorder itself.

The influence of the COMT genotype in the underlying functional brain activity of context processing in schizophrenia and in relatives.

PubMed

Lopez-Garcia, Pilar; Cristobal-Huerta, Alexandra; Young Espinoza, Leslie; Molero, Patricio; Ortuño Sanchez-Pedreño, Felipe; Hernández-Tamames, Juan Antonio

2016-11-03

Context processing deficits have been shown to be present in chronic and first episode schizophrenia patients and in their relatives. This cognitive process is linked to frontal functioning and is highly dependent on dopamine levels in the prefrontal cortex (PFC). The catechol-O-methyltransferase (COMT) enzyme plays a prominent role in regulating dopamine levels in PFC. Genotypic variations in the functional polymorphism Val(158)Met COMT appear to have an impact in dopamine signaling in the PFC of healthy subjects and schizophrenia patients. We aimed to explore the effect of the Val(158)Met COMT polymorphism on brain activation during the performance of a context processing task in healthy subjects, schizophrenia spectrum patients and their healthy relatives. 56 participants performed the Dot Probe Expectancy task (DPX) during the fMRI session. Subjects were genotyped and only the Val and Met homozygotes participated in the study. Schizophrenia spectrum patients and their relatives showed worse performance on context processing measures than healthy control subjects. The Val allele was associated with more context processing errors in healthy controls and in relatives compared to patients. There was a greater recruitment of frontal areas (supplementary motor area/cingulate gyrus) during context processing in patients relative to healthy controls. Met homozygotes subjects activated more frontal areas than Val homozygotes subjects. The Val(158)Met COMT polymorphism influences context processing and on its underlying brain activation, showing less recruitment of frontal areas in the subjects with the genotype associated to lower dopamine availability in PFC. Copyright © 2016. Published by Elsevier Inc.

Polymorphisms in monolignol biosynthetic genes are associated with biomass yield and agronomic traits in European maize (Zea mays L.).

PubMed

Chen, Yongsheng; Zein, Imad; Brenner, Everton Alen; Andersen, Jeppe Reitan; Landbeck, Mathias; Ouzunova, Milena; Lübberstedt, Thomas

2010-01-15

Reduced lignin content leads to higher cell wall digestibility and, therefore, better forage quality and increased conversion of lignocellulosic biomass into ethanol. However, reduced lignin content might lead to weaker stalks, lodging, and reduced biomass yield. Genes encoding enzymes involved in cell wall lignification have been shown to influence both cell wall digestibility and yield traits. In this study, associations between monolignol biosynthetic genes and plant height (PHT), days to silking (DTS), dry matter content (DMC), and dry matter yield (DMY) were identified by using a panel of 39 European elite maize lines. In total, 10 associations were detected between polymorphisms or tight linkage disequilibrium (LD) groups within the COMT, CCoAOMT2, 4CL1, 4CL2, F5H, and PAL genomic fragments, respectively, and the above mentioned traits. The phenotypic variation explained by these polymorphisms or tight LD groups ranged from 6% to 25.8% in our line collection. Only 4CL1 and F5H were found to have polymorphisms associated with both yield and forage quality related characters. However, no pleiotropic polymorphisms affecting both digestibility of neutral detergent fiber (DNDF), and PHT or DMY were discovered, even under less stringent statistical conditions. Due to absence of pleiotropic polymorphisms affecting both forage yield and quality traits, identification of optimal monolignol biosynthetic gene haplotype(s) combining beneficial quantitative trait polymorphism (QTP) alleles for both quality and yield traits appears possible within monolignol biosynthetic genes. This is beneficial to maximize forage and bioethanol yield per unit land area.

Polymorphisms in monolignol biosynthetic genes are associated with biomass yield and agronomic traits in European maize (Zea mays L.)

PubMed Central

2010-01-01

Background Reduced lignin content leads to higher cell wall digestibility and, therefore, better forage quality and increased conversion of lignocellulosic biomass into ethanol. However, reduced lignin content might lead to weaker stalks, lodging, and reduced biomass yield. Genes encoding enzymes involved in cell wall lignification have been shown to influence both cell wall digestibility and yield traits. Results In this study, associations between monolignol biosynthetic genes and plant height (PHT), days to silking (DTS), dry matter content (DMC), and dry matter yield (DMY) were identified by using a panel of 39 European elite maize lines. In total, 10 associations were detected between polymorphisms or tight linkage disequilibrium (LD) groups within the COMT, CCoAOMT2, 4CL1, 4CL2, F5H, and PAL genomic fragments, respectively, and the above mentioned traits. The phenotypic variation explained by these polymorphisms or tight LD groups ranged from 6% to 25.8% in our line collection. Only 4CL1 and F5H were found to have polymorphisms associated with both yield and forage quality related characters. However, no pleiotropic polymorphisms affecting both digestibility of neutral detergent fiber (DNDF), and PHT or DMY were discovered, even under less stringent statistical conditions. Conclusion Due to absence of pleiotropic polymorphisms affecting both forage yield and quality traits, identification of optimal monolignol biosynthetic gene haplotype(s) combining beneficial quantitative trait polymorphism (QTP) alleles for both quality and yield traits appears possible within monolignol biosynthetic genes. This is beneficial to maximize forage and bioethanol yield per unit land area. PMID:20078869

Simultaneous Downregulation of MTHFR and COMT in Switchgrass Affects Plant Performance and Induces Lesion-Mimic Cell Death.

PubMed

Liu, Sijia; Fu, Chunxiang; Gou, Jiqing; Sun, Liang; Huhman, David; Zhang, Yunwei; Wang, Zeng-Yu

2017-01-01

Switchgrass ( Panicum virgatum ) has been developed into a model lignocellulosic bioenergy crop. Downregulation of caffeic acid O -methyltransferase (COMT), a key enzyme in lignin biosynthesis, has been shown to alter lignification and increase biofuel yield in switchgrass. Methylenetetrahydrofolate reductase (MTHFR) mediates C1 metabolism and provides methyl units consumed by COMT. It was predicted that co-silencing of MTHFR and COMT would impact lignification even more than either of the single genes. However, our results showed that strong downregulation of MTHFR in a COMT -deficient background led to altered plant growth and development, but no significant change in lignin content or composition was found when compared with COMT plants. Another unexpected finding was that the double MTHFR/COMT downregulated plants showed a novel lesion-mimic leaf phenotype. Molecular analyses revealed that the lesion-mimic phenotype was caused by the synergistic effect of MTHFR and COMT genes, with MTHFR playing a predominant role. Microarray analysis showed significant induction of genes related to oxidative and defense responses. The results demonstrated the lack of additive effects of MTHFR and COMT on lignification. Furthermore, this research revealed an unexpected role of the two genes in the modulation of lesion-mimic cell death as well as their synergistic effects on agronomic performance.

Simultaneous Downregulation of MTHFR and COMT in Switchgrass Affects Plant Performance and Induces Lesion-Mimic Cell Death

PubMed Central

Liu, Sijia; Fu, Chunxiang; Gou, Jiqing; Sun, Liang; Huhman, David; Zhang, Yunwei; Wang, Zeng-Yu

2017-01-01

Switchgrass (Panicum virgatum) has been developed into a model lignocellulosic bioenergy crop. Downregulation of caffeic acid O-methyltransferase (COMT), a key enzyme in lignin biosynthesis, has been shown to alter lignification and increase biofuel yield in switchgrass. Methylenetetrahydrofolate reductase (MTHFR) mediates C1 metabolism and provides methyl units consumed by COMT. It was predicted that co-silencing of MTHFR and COMT would impact lignification even more than either of the single genes. However, our results showed that strong downregulation of MTHFR in a COMT-deficient background led to altered plant growth and development, but no significant change in lignin content or composition was found when compared with COMT plants. Another unexpected finding was that the double MTHFR/COMT downregulated plants showed a novel lesion-mimic leaf phenotype. Molecular analyses revealed that the lesion-mimic phenotype was caused by the synergistic effect of MTHFR and COMT genes, with MTHFR playing a predominant role. Microarray analysis showed significant induction of genes related to oxidative and defense responses. The results demonstrated the lack of additive effects of MTHFR and COMT on lignification. Furthermore, this research revealed an unexpected role of the two genes in the modulation of lesion-mimic cell death as well as their synergistic effects on agronomic performance. PMID:28676804

Childhood Abuse Experiences and the COMT and MTHFR Genetic Variants Associated With Male Sexual Orientation in the Han Chinese Populations: A Case-Control Study.

PubMed

Qin, Jia-Bi; Zhao, Guang-Lu; Wang, Feng; Cai, Yu-Mao; Lan, Li-Na; Yang, Lin; Feng, Tie-Jian

2018-01-01

Although it is widely acknowledged that genetic and environmental factors are involved in the development of male homosexuality, the causes are not fully understood. To explore the association and interaction of childhood abuse experiences and genetic variants of the catechol-O-methyltransferase (COMT) and methylenetetrahydrofolate reductase (MTHFR) genes with the development of male homosexuality. A case-control study of 537 exclusively homosexual men and 583 exclusively heterosexual men was conducted, with data collected from March 2013 to August 2015. Data were analyzed using χ 2 tests and logistic regression models. Sociodemographic characteristics, childhood abuse experiences, and polymorphisms of COMT at rs4680, rs4818, and rs6267 and MTHFR at rs1801133. More frequent occurrence of physical (adjusted odds ratio [aOR] = 1.78), emotional (aOR = 2.07), and sexual (aOR = 2.53) abuse during childhood was significantly associated with the development of male homosexuality. The polymorphisms of MTHFR at rs1801133 and COMT at rs4818 also were significantly associated with the development of male homosexuality in the homozygote comparisons (T/T vs C/C at rs1801133, aOR = 1.68; G/G vs C/C at rs4818, aOR = 1.75). In addition, significant interaction effects between childhood abuse experiences and the COMT and MTHFR genetic variants on the development of male homosexuality were found. This is the first time that an association of childhood abuse, COMT and MTHFR genetic variants, and their interactions with development of male homosexuality was exhaustively explored, which could help provide new insight into the etiology of male homosexuality. Because homosexual men are a relatively obscure population, it was impossible to select the study participants by random sampling, which could lead to selection bias. In addition, because this was a case-control study, recall bias was inevitable, and we could not verify causality. Childhood abuse and the COMT and MTHFR genetic variants could be positively associated with the development of homosexuality. However, it remains unknown how these factors jointly play a role in the development of homosexuality, and more studies in different ethnic populations and with a larger sample and a prospective design are required to confirm our findings. Qin J-B, Zhao G-L, Wang F, et al. Childhood Abuse Experiences and the COMT and MTHFR Genetic Variants Associated With Male Sexual Orientation in the Han Chinese Populations: A Case-Control Study. J Sex Med 2018;15:29-42. Copyright © 2017 International Society for Sexual Medicine. Published by Elsevier Inc. All rights reserved.

Biological Effects of COMT Haplotypes and Psychosis Risk in 22q11.2 Deletion Syndrome

PubMed Central

Gothelf, Doron; Law, Amanda J.; Frisch, Amos; Chen, Jingshan; Zarchi, Omer; Michaelovsky, Elena; Ren-Patterson, Renee; Lipska, Barbara K.; Carmel, Miri; Kolachana, Bhaskar; Weizman, Abraham; Weinberger, Daniel R.

2013-01-01

Background 22q11.2 deletion syndrome (22q11.2DS) is the most common genetic syndrome associated with schizophrenia. The catechol-o-methyltransferase (COMT) gene is located in the obligatory deletion region, and possible associations between COMT variants and neuropsychiatric manifestations in 22q11.2DS have been reported. The purpose of the current study was to evaluate the effect of COMT hemizygosity and molecular haplotypes on gene expression and enzyme activity and its association with psychotic symptoms in 22q11.2DS. Methods Lymphoblast samples were drawn from 53 individuals with 22q11.2DS and 16 typically developing controls. We measured COMT mRNA and protein expression and enzyme activity using standard procedures. The presence of a psychotic disorder and cognitive deficits were also evaluated using structured testing. Results There was a ~50% reduction in COMT mRNA, protein and enzyme activity levels in 22q11.2DS samples. Haplotype analysis revealed clear phenotypic differences between various Val-containing haplotypes on COMT-3′UTR extended mRNA, S-COMT and MB proteins and enzyme activity. The G variant of rs165599, a 3′UTR SNP, was associated with low levels of COMT expression and with the presence of psychosis and lower performance IQ scores in our 22q11.2DS sample. Finally, we demonstrate that the COMT rs74745580 ‘T’ mutation is associated with absent S-COMT expression and very low COMT activity in two 22q11.2DS individuals. Conclusions Our findings confirm a robust effect of COMT hemizygosity on COMT activity and show complex interactions of variants within the COMT gene that influence COMT biology and confound conclusions based on associations with the Val158Met genotype alone. PMID:23992923

Child Exposure to Serious Life Events, COMT, and Aggression: Testing Differential Susceptibility Theory

ERIC Educational Resources Information Center

Hygen, Beate Wold; Belsky, Jay; Stenseng, Frode; Lydersen, Stian; Guzey, Ismail Cuneyt; Wichstrøm, Lars

2015-01-01

Both genetic and environmental factors contribute to individual differences in aggression. Catechol-O-methyltransferase Val158Met (COMT), a common, functional polymorphism, has been implicated in aggression and aggression traits, as have childhood experiences of adversity. It is unknown whether these effects are additive or interactional and, in…

Does COMT genotype influence the effects of d-amphetamine on executive functioning?

PubMed Central

Wardle, Margaret C.; Hart, Amy B.; Palmer, Abraham A.; de Wit, Harriet

2012-01-01

In a widely cited study, Mattay et al. (2003) reported that amphetamine (0.25 mg/kg oral, or 17mg for a 68kg individual) impaired behavioral and brain indices of executive functioning, measured using the Wisconsin Card Sorting Task (WCST) and N-Back working memory task, in 6 individuals homozygous for the met allele of the val158met polymorphism in the catechol-O-methyltransferase (COMT) gene, whereas it improved executive functioning in 10 individuals homozygous for the more active val allele. We attempted to replicate their behavioral findings in a larger sample, using similar executive functioning tasks and a broader range of amphetamine doses. Over four sessions, n = 200 healthy normal adults received oral placebo, d-amphetamine 5mg, 10mg, and 20mg (average of 0.07, 0.15 and 0.29 mg/kg), under counterbalanced double-blind conditions, and completed WCST and N-back tests of executive functioning. Amphetamine had typical effects on blood pressure and processing speed but did not affect executive functioning. COMT genotype (val158met) was not related to executive functioning under placebo or amphetamine conditions, even when we compared only the homozygous val/val and met/met genotypes at the highest dose of amphetamine (20 mg). Thus, we were not able to replicate the behavioral interaction between COMT and amphetamine seen in Mattay et al. (Mattay et al., 2003). We discuss possible differences between the studies and the implications of our findings for the use of COMT genotyping to predict clinical responses to dopaminergic drugs, and the use of intermediate phenotypes in genetic research. PMID:23231539

Estrogen-DNA Adducts as Novel Biomarkers for Ovarian Cancer Risk and for Use in Prevention

DTIC Science & Technology

2013-03-01

genes for four selected estrogen-metabolizing enzymes : cytochrome P450 (CYP)1A1 (I462V), CYP1B1 (V432L),catechol-O-methyltransferase (COMT) (V158M...homozygous for the catechol-O-methyltransferase allele and the cytochrome P450 1B1 high activity allele had significantly increased DNA adduct ratios and... enzyme polymorphisms to serve as biomarkers to screen for ovarian cancer . Task 1. Obtain approval of the protocol from the OCRP Human Research

Association of catechol-O-methyltransferase genetic variants with outcome in patients undergoing surgical treatment for lumbar degenerative disc disease.

PubMed

Dai, Feng; Belfer, Inna; Schwartz, Carolyn E; Banco, Robert; Martha, Julia F; Tighioughart, Hocine; Tromanhauser, Scott G; Jenis, Louis G; Kim, David H

2010-11-01

Surgical treatment for lumbar degenerative disc disease (DDD) has been associated with highly variable results in terms of postoperative pain relief and functional improvement. Many experts believe that DDD should be considered a chronic pain disorder as opposed to a degenerative disease. Genetic variation of the catechol-O-methyltransferase (COMT) gene has been associated with variation in human pain sensitivity and response to analgesics in previous studies. To determine whether genetic variation of COMT is associated with clinical outcome after surgical treatment for DDD. Prospective genetic association study. Sixty-nine patients undergoing surgical treatment for lumbar DDD. Diagnosis was based on documentation of chronic disabling low back pain (LBP) present for a minimum of 6 months and unresponsive to supervised nonoperative treatment, including activity modification, medication, physical therapy, and/or injection therapy. Plain radiographs and magnetic resonance imaging revealed intervertebral disc desiccation, tears, and/or collapse without focal herniation, nerve root compression, stenosis, spondylolisthesis, spondylolysis, or alternative diagnoses. Oswestry Disability Index (ODI) and visual analog score (VAS) for LBP. Surgical treatment included 65 instrumented fusions and four disc arthroplasty procedures. All patients completed preoperative and 1-year postoperative ODI questionnaires. DNA was extracted from a sample of venous blood, and genotype analysis was performed for five common COMT single nucleotide polymorphisms (SNPs). Potential genetic association between these COMT SNPs and the primary outcome variable, 1-year change in ODI, was investigated using both single-marker and haplotype association analyses. Association with VAS scores for LBP was analyzed as a secondary outcome variable. Single-marker analysis revealed that the COMT SNP rs4633 was significantly associated with greater improvement in ODI score 1 year after surgery (p=.03), with individuals homozygous for the less common "T" allele demonstrating the largest improvement in ODI. Haplotype analysis of four COMT SNPs, rs6269, rs4633, rs4818, and rs4680, also identified a common haplotype "ATCA" (haplotype frequency of 39.3% in the study population) associated with greater improvement in ODI (p=.046). The greatest mean improvement in ODI was observed in patients homozygous for the "ATCA"COMT haplotype. A nonsignificant trend was observed between SNP rs4633 and greater improvement in VAS score for LBP. This is the first study to report an association between surgical treatment success in DDD patients and genetic variation in the putative pain sensitivity gene COMT. These findings require replication in other DDD populations but suggest that genetic testing for pain-relevant genetic markers such as COMT may provide useful clinical information in terms of predicting outcome after surgery for patients diagnosed with DDD. Copyright © 2010 Elsevier Inc. All rights reserved.

Pharmacogenetic analysis of opioid dependence treatment dose and dropout rate.

PubMed

Crist, Richard C; Li, James; Doyle, Glenn A; Gilbert, Alex; Dechairo, Bryan M; Berrettini, Wade H

2018-01-01

Currently, no pharmacogenetic tests for selecting an opioid-dependence pharmacotherapy have been approved by the US Food and Drug Administration. Determine the effects of variants in 11 genes on dropout rate and dose in patients receiving methadone or buprenorphine/naloxone (ClinicalTrials.gov Identifier: NCT00315341). Variants in six pharmacokinetic genes (CYP1A2, CYP2B6, CYP2C19, CYP2C9, CYP2D6, CYP3A4) and five pharmacodynamic genes (HTR2A, OPRM1, ADRA2A, COMT, SLC6A4) were genotyped in samples from a 24-week, randomized, open-label trial of methadone and buprenorphine/naloxone for the treatment of opioid dependence (n = 764; 68.7% male). Genotypes were then used to determine the metabolism phenotype for each pharmacokinetic gene. Phenotypes or genotypes for each gene were analyzed for association with dropout rate and mean dose. Genotype for 5-HTTLPR in the SLC6A4 gene was nominally associated with dropout rate when the methadone and buprenorphine/naloxone groups were combined. When the most significant variants associated with dropout rate were analyzed using pairwise analyses, SLC6A4 (5-HTTLPR) and COMT (Val158Met; rs4860) had nominally significant associations with dropout rate in methadone patients. None of the genes analyzed in the study was associated with mean dose of methadone or buprenorphine/naloxone. This study suggests that functional polymorphisms related to synaptic dopamine or serotonin levels may predict dropout rates during methadone treatment. Patients with the S/S genotype at 5-HTTLPR in SLC6A4 or the Val/Val genotype at Val158Met in COMT may require additional treatment to improve their chances of completing addiction treatment. Replication in other methadone patient populations will be necessary to ensure the validity of these findings.

A replicated molecular genetic basis for subtyping antisocial behavior in children with attention-deficit/hyperactivity disorder.

PubMed

Caspi, Avshalom; Langley, Kate; Milne, Barry; Moffitt, Terrie E; O'Donovan, Michael; Owen, Michael J; Polo Tomas, Monica; Poulton, Richie; Rutter, Michael; Taylor, Alan; Williams, Benjamin; Thapar, Anita

2008-02-01

Attention-deficit/hyperactivity disorder (ADHD) is a heterogeneous neurodevelopmental disorder that in some cases is accompanied by antisocial behavior. To test if variations in the catechol O-methyltransferase gene (COMT) would prove useful in identifying the subset of children with ADHD who exhibit antisocial behavior. Three independent samples composed of 1 clinical sample of ADHD cases and 2 birth cohort studies. Participants in the clinical sample were drawn from child psychiatry and child health clinics in England and Wales. The 2 birth cohort studies included 1 sample of 2232 British children born in 1994-1995 and a second sample of 1037 New Zealander children born in 1972-1973. Diagnosis of ADHD and measures of antisocial behavior. We present replicated evidence that the COMT valine/methionine polymorphism at codon 158 (COMT Val158Met) was associated with phenotypic variation among children with ADHD. Across the 3 samples, valine/valine homozygotes had more symptoms of conduct disorder, were more aggressive, and were more likely to be convicted of criminal offenses compared with methionine carriers. The findings confirm the presence of genetic heterogeneity in ADHD and illustrate how genetic information may provide biological evidence pointing to clinical subtypes.

CENTEC: Center for Excellence in Neuroergonomics, Technology, and Cognition

DTIC Science & Technology

2016-10-26

paper, "Interactive Effects of the COMT Gene and Training on Individual Differences in Supervisory Control of Unmanned Vehicles." Awards to Raja...in the DBH gene on performance on a command-and-control task (Parasuraman et al., 2012), the effects of variation in the COMT gene on supervisory...control of unmanned vehicles (Parasuraman et al., 2014), and were the first to report the combined effect of COMT and DBH genes on extracellular

COMT Val(108/158)Met polymorphism effects on emotional brain function and negativity bias.

PubMed

Williams, Leanne M; Gatt, Justine M; Grieve, Stuart M; Dobson-Stone, Carol; Paul, Robert H; Gordon, Evian; Schofield, Peter R

2010-11-15

Biases toward processing negative versus positive information vary as a function of level of awareness, and are modulated by monoamines. Excessive biases are associated with individual differences in mood and emotional stability, and emotional disorder. Here, we examined the impact of the catechol-O-methyltransferase (COMT) Val(108/158)Met polymorphism, involved in dopamine and norepinephrine catabolism, on both emotional brain function and self-reported negativity bias. COMT genotyping and self-reported level of negativity bias were completed for 46 healthy participants taking part in the Brain Resource International Database. Functional MRI was undertaken during perception of facial expressions of fear and happiness presented under unmasked (consciously identified) and masked (to prevent conscious detection) conditions. Structural MR images were also acquired. A greater number of COMT Met alleles predicted increased activation in brainstem, amygdala, basal ganglia and medial prefrontal regions for conscious fear, but decreased activation for conscious happiness. This pattern was also apparent for brainstem activation for the masked condition. Effects were most apparent for females. These differences could not be explained by gray matter variations. The Met-related profile of activation, particularly prefrontally, predicted greater negativity bias associated with risk for emotional disorder. The findings suggest that the COMT Met allele modulates neural substrates of negative versus positive emotion processing. This effect may contribute to negativity biases, which confer susceptibility for emotional disorders. Copyright 2010 Elsevier Inc. All rights reserved.

Modification of Depression by COMT val[superscript 158]Met Polymorphism in Children Exposed to Early Severe Psychosocial Deprivation

ERIC Educational Resources Information Center

Drury, Stacy S.; Theall, Katherine P.; Smyke, Anna T.; Keats, Bronya J. B.; Egger, Helen L.; Nelson, Charles A.; Fox, Nathan A.; Marshall, Peter J.; Zeanah, Charles H.

2010-01-01

Objective: To examine the impact of the catechol-O-methyltransferase (COMT) val[superscript 158]met allele on depressive symptoms in young children exposed to early severe social deprivation as a result of being raised in institutions. Methods: One hundred thirty six children from the Bucharest Early Intervention Project (BEIP) were randomized…

Association of genetic and psychological factors with persistent pain after cosmetic thoracic surgery

PubMed Central

Dimova, Violeta; Lötsch, Jörn; Hühne, Kathrin; Winterpacht, Andreas; Heesen, Michael; Parthum, Andreas; Weber, Peter G; Carbon, Roman; Griessinger, Norbert; Sittl, Reinhard; Lautenbacher, Stefan

2015-01-01

The genetic control of pain has been repeatedly demonstrated in human association studies. In the present study, we assessed the relative contribution of 16 single nucleotide polymorphisms in pain-related genes, such as cathechol-O-methyl transferase gene (COMT), fatty acid amino hydrolase gene (FAAH), transient receptor potential cation channel, subfamily V, member 1 gene (TRPV1), and δ-opioid receptor gene (OPRD1), for postsurgical pain chronification. Ninety preoperatively pain-free male patients were assigned to good or poor outcome groups according to their intensity or disability score assessed at 1 week, 3 months, 6 months, and 1 year after funnel chest correction. The genetic effects were compared with those of two psychological predictors, the attentional bias toward positive words (dot-probe task) and the self-reported pain vigilance (Pain Vigilance and Awareness Questionnaire [PVAQ]), which were already shown to be the best predictors for pain intensity and disability at 6 months after surgery in the same sample, respectively. Cox regression analyses revealed no significant effects of any of the genetic predictors up to the end point of survival time at 1 year after surgery. Adding the genetics to the prediction by the attentional bias to positive words for pain intensity and the PVAQ for pain disability, again no significant additional explanation could be gained by the genetic predictors. In contrast, the preoperative PVAQ score was also, in the present enlarged sample, a meaningful predictor for lasting pain disability after surgery. Effect size measures suggested some genetic variables, for example, the polymorphism rs1800587G>A in the interleukin 1 alpha gene (IL1A) and the COMT haplotype rs4646312T>C/rs165722T>C/rs6269A>G/rs4633T>C/rs4818C>G/rs4680A>G, as possible relevant modulators of long-term postsurgical pain outcome. A comparison between pathophysiologically different predictor groups appears to be helpful in identifying clinically relevant predictors of chronic pain. PMID:26664154

The Role of the Catechol-o-methyltransferase (COMT) Gene Val158Met in Aggressive Behavior, A Review of Genetic Studies

PubMed Central

Qayyum, Arqam; Zai, Clement C.; Hirata, Yuko; Tiwari, Arun K.; Cheema, Sheraz; Nowrouzi, Behdin; Beitchman, Joseph H.; Kennedy, James L.

2015-01-01

Aggressive behaviors have become a major public health problem, and early-onset aggression can lead to outcomes such as substance abuse, antisocial personality disorder among other issues. In recent years, there has been an increase in research in the molecular and genetic underpinnings of aggressive behavior, and one of the candidate genes codes for the catechol-O-methyltransferase (COMT). COMT is involved in catabolizing catecholamines such as dopamine. These neurotransmitters appear to be involved in regulating mood which can contribute to aggression. The most common gene variant studied in the COMT gene is the Valine (Val) to Methionine (Met) substitution at codon 158. We will be reviewing the current literature on this gene variant in aggressive behavior. PMID:26630958

Crystal structures of human 108V and 108M catechol O-methyltransferase

DOE Office of Scientific and Technical Information (OSTI.GOV)

Rutherford, K.; Le Trong, I.; Stenkamp, R.E.

2008-08-01

Catechol O-methyltransferase (COMT) plays important roles in the metabolism of catecholamine neurotransmitters and catechol estrogens. The development of COMT inhibitors for use in the treatment of Parkinson's disease has been aided by crystallographic structures of the rat enzyme. However, the human and rat proteins have significantly different substrate specificities. Additionally, human COMT contains a common valine-methionine polymorphism at position 108. The methionine protein is less stable than the valine polymorph, resulting in decreased enzyme activity and protein levels in vivo. Here we describe the crystal structures of the 108V and 108M variants of the soluble form of human COMT boundmore » with S-adenosylmethionine (SAM) and a substrate analog, 3,5-dinitrocatechol. The polymorphic residue 108 is located in the {alpha}5-{beta}3 loop, buried in a hydrophobic pocket {approx}16 {angstrom} from the SAM-binding site. The 108V and 108M structures are very similar overall [RMSD of C{sup {alpha}} atoms between two structures (C{sup {alpha}} RMSD) = 0.2 {angstrom}], and the active-site residues are superposable, in accord with the observation that SAM stabilizes 108M COMT. However, the methionine side chain is packed more tightly within the polymorphic site and, consequently, interacts more closely with residues A22 ({alpha}2) and R78 ({alpha}4) than does valine. These interactions of the larger methionine result in a 0.7-{angstrom} displacement in the backbone structure near residue 108, which propagates along {alpha}1 and {alpha}5 toward the SAM-binding site. Although the overall secondary structures of the human and rat proteins are very similar (C{sup {alpha}} RMSD = 0.4 {angstrom}), several nonconserved residues are present in the SAM-(I89M, I91M, C95Y) and catechol- (C173V, R201M, E202K) binding sites. The human protein also contains three additional solvent-exposed cysteine residues (C95, C173, C188) that may contribute to intermolecular disulfide bond formation and protein aggregation.« less

Time-Resolved Influences of Functional DAT1 and COMT Variants on Visual Perception and Post-Processing

PubMed Central

Bender, Stephan; Rellum, Thomas; Freitag, Christine; Resch, Franz; Rietschel, Marcella; Treutlein, Jens; Jennen-Steinmetz, Christine; Brandeis, Daniel; Banaschewski, Tobias; Laucht, Manfred

2012-01-01

Background Dopamine plays an important role in orienting and the regulation of selective attention to relevant stimulus characteristics. Thus, we examined the influences of functional variants related to dopamine inactivation in the dopamine transporter (DAT1) and catechol-O-methyltransferase genes (COMT) on the time-course of visual processing in a contingent negative variation (CNV) task. Methods 64-channel EEG recordings were obtained from 195 healthy adolescents of a community-based sample during a continuous performance task (A-X version). Early and late CNV as well as preceding visual evoked potential components were assessed. Results Significant additive main effects of DAT1 and COMT on the occipito-temporal early CNV were observed. In addition, there was a trend towards an interaction between the two polymorphisms. Source analysis showed early CNV generators in the ventral visual stream and in frontal regions. There was a strong negative correlation between occipito-temporal visual post-processing and the frontal early CNV component. The early CNV time interval 500–1000 ms after the visual cue was specifically affected while the preceding visual perception stages were not influenced. Conclusions Late visual potentials allow the genomic imaging of dopamine inactivation effects on visual post-processing. The same specific time-interval has been found to be affected by DAT1 and COMT during motor post-processing but not motor preparation. We propose the hypothesis that similar dopaminergic mechanisms modulate working memory encoding in both the visual and motor and perhaps other systems. PMID:22844499

Race moderates the association of Catechol-O-methyltransferase genotype and posttraumatic stress disorder in preschool children.

PubMed

Humphreys, Kathryn L; Scheeringa, Michael S; Drury, Stacy S

2014-10-01

The present study sought to replicate previous findings of an association between the Catechol-O-methyltransferase (COMT) val158met polymorphism with posttraumatic stress disorder (PTSD) and symptomatology in a novel age group, preschool children. COMT genotype was determined in a sample of 171 3-6-year-old trauma-exposed children. PTSD was assessed with a semistructured interview. Accounting for sex, trauma type, and age, genotype was examined in relation to categorical and continuous measures of PTSD both controlling for race and within the two largest racial categories (African American [AA] and European American [EA]). Race significantly moderated the association between genotype and PTSD. Specifically, the genotype associated with increased PTSD symptoms in one racial group had the opposite association in the other racial group. For AA children the met/met genotype was associated with more PTSD symptoms. However, for EA children, val allele carriers had more PTSD symptoms. Whereas every AA child with the met/met genotype met criteria for PTSD, none of the EA children with the met/met genotype did. This genetic association with COMT genotype, in both races but in opposite directions, was most associated with increased arousal symptoms. These findings replicate previous findings in participants of African descent, highlight the moderating effect of race on the association between COMT genotype and PTSD, and provide direct evidence that consideration of population stratification within gene-by-environment studies is valuable to prevent false negative findings.

Race Moderates the Association of Catechol-O-methyltransferase Genotype and Posttraumatic Stress Disorder in Preschool Children

PubMed Central

Humphreys, Kathryn L.; Scheeringa, Michael S.

2014-01-01

Abstract Objective: The present study sought to replicate previous findings of an association between the Catechol-O-methyltransferase (COMT) val158met polymorphism with posttraumatic stress disorder (PTSD) and symptomatology in a novel age group, preschool children. Methods: COMT genotype was determined in a sample of 171 3–6-year-old trauma-exposed children. PTSD was assessed with a semistructured interview. Accounting for sex, trauma type, and age, genotype was examined in relation to categorical and continuous measures of PTSD both controlling for race and within the two largest racial categories (African American [AA] and European American [EA]). Results: Race significantly moderated the association between genotype and PTSD. Specifically, the genotype associated with increased PTSD symptoms in one racial group had the opposite association in the other racial group. For AA children the met/met genotype was associated with more PTSD symptoms. However, for EA children, val allele carriers had more PTSD symptoms. Whereas every AA child with the met/met genotype met criteria for PTSD, none of the EA children with the met/met genotype did. This genetic association with COMT genotype, in both races but in opposite directions, was most associated with increased arousal symptoms. Conclusions: These findings replicate previous findings in participants of African descent, highlight the moderating effect of race on the association between COMT genotype and PTSD, and provide direct evidence that consideration of population stratification within gene-by-environment studies is valuable to prevent false negative findings. PMID:25329975

Time-resolved influences of functional DAT1 and COMT variants on visual perception and post-processing.

PubMed

Bender, Stephan; Rellum, Thomas; Freitag, Christine; Resch, Franz; Rietschel, Marcella; Treutlein, Jens; Jennen-Steinmetz, Christine; Brandeis, Daniel; Banaschewski, Tobias; Laucht, Manfred

2012-01-01

Dopamine plays an important role in orienting and the regulation of selective attention to relevant stimulus characteristics. Thus, we examined the influences of functional variants related to dopamine inactivation in the dopamine transporter (DAT1) and catechol-O-methyltransferase genes (COMT) on the time-course of visual processing in a contingent negative variation (CNV) task. 64-channel EEG recordings were obtained from 195 healthy adolescents of a community-based sample during a continuous performance task (A-X version). Early and late CNV as well as preceding visual evoked potential components were assessed. Significant additive main effects of DAT1 and COMT on the occipito-temporal early CNV were observed. In addition, there was a trend towards an interaction between the two polymorphisms. Source analysis showed early CNV generators in the ventral visual stream and in frontal regions. There was a strong negative correlation between occipito-temporal visual post-processing and the frontal early CNV component. The early CNV time interval 500-1000 ms after the visual cue was specifically affected while the preceding visual perception stages were not influenced. Late visual potentials allow the genomic imaging of dopamine inactivation effects on visual post-processing. The same specific time-interval has been found to be affected by DAT1 and COMT during motor post-processing but not motor preparation. We propose the hypothesis that similar dopaminergic mechanisms modulate working memory encoding in both the visual and motor and perhaps other systems.

Left Parietal Functional Connectivity Mediates the Association Between COMT rs4633 and Verbal Intelligence in Healthy Adults

PubMed Central

Xu, Qiang; Fu, Jilian; Liu, Feng; Qin, Wen; Liu, Bing; Jiang, Tianzi; Yu, Chunshui

2018-01-01

In Chinese Han population, Catechol-O-methyltransferase gene (COMT) rs4633 is found to be associated with impaired cognitive process. We aimed to investigate the association between COMT rs4633 and verbal intelligence and the underlying neural mechanisms in Chinese Han healthy young adults. In 256 Chinese Han healthy young adults, we explored the modulatory effects of COMT rs4633 on verbal intelligence quotient (VIQ) and functional connectivity density (FCD) of the brain and the mediation effect of FCD on the association between COMT and VIQ. We further investigated the association between the expression patterns of dopamine receptor genes and the effect of COMT on FCD in the human brain. COMT rs4633 TT homozygotes exhibited lower VIQ than CC homozygotes and TC heterozygotes, higher long-range FCD (lrFCD) than CC homozygotes and TC heterozygotes in the left superior frontal gyrus. TT homozygotes and TC heterozygotes showed higher lrFCD than CC homozygotes in the left inferior parietal lobule. The lrFCD differences across genotypic subgroups were negatively associated with the expression of DRD2 and DRD3 genes. The left parietal lrFCD mediated the association between COMT rs4633 and VIQ. These findings provide a biological pathway that COMT rs4633 affects verbal intelligence via modulating the lrFCD of the left inferior parietal lobule. PMID:29692704

Stressful life events, perceived stress, and 12-month course of geriatric depression: direct effects and moderation by the 5-HTTLPR and COMT Val158Met polymorphisms.

PubMed

Zannas, Anthony S; McQuoid, Douglas R; Steffens, David C; Chrousos, George P; Taylor, Warren D

2012-07-01

Although the relation between stressful life events (SLEs) and risk of major depressive disorder is well established, important questions remain about the effects of stress on the course of geriatric depression. Our objectives were (1) to examine how baseline stress and change in stress is associated with course of geriatric depression and (2) to test whether polymorphisms of serotonin transporter (5-HTTLPR) and catechol-O-methyltransferase (COMT Val158Met) genes moderate this relation. Two-hundred and sixteen depressed subjects aged 60 years or older were categorized by remission status (Montgomery-Asberg depression rating scale≤6) at 6 and 12 months. At 6 months, greater baseline numbers of self-reported negative and total SLEs and greater baseline perceived stress severity were associated with lower odds of remission. At 12 months, only baseline perceived stress predicted remission. When we examined change in stress, 12-month decrease in negative SLEs and level of perceived stress were associated with improved odds of 12-month remission. When genotype data were included, COMT Val158Met genotype did not influence these relations. However, when compared with 5-HTTLPR L/L homozygotes, S allele carriers with greater baseline numbers of negative SLEs and with greater decrease in negative SLEs were more likely to remit at 12 months. This study demonstrates that baseline SLEs and perceived stress severity may influence the 12-month course of geriatric depression. Moreover, changes in these stress measures over time correlate with depression outcomes. 5-HTTLPR S carriers appear to be more susceptible to both the effects of enduring stress and the benefit of interval stress reduction.

Catechol-o-methyl transferase (COMT) val158met polymorphism and adolescent cortical development in patients with childhood-onset schizophrenia, their non-psychotic siblings, and healthy controls

PubMed Central

Raznahan, Armin; Greenstein, Deanna; Lee, Yohan; Long, Robert; Clasen, Liv; Gochman, Pete; Addington, Anjene; Giedd, Jay N.; Rapoport, Judith L.; Gogtay, Nitin

2012-01-01

Non-psychotic individuals at increased risk for schizophrenia show alterations in fronto-striatal dopamine signaling and cortical gray matter maturation reminiscent of those seen in schizophrenia. It remains unclear however if variations in dopamine signaling influence rates of structural cortical maturation in typically developing individuals, and whether such influences are disrupted in patients with schizophrenia and their non-psychotic siblings. We sought to address these issues by relating a functional Val→Met polymorphism within the gene encoding catechol-o-methyltransferase (COMT)—a key enzymatic regulator of cortical dopamine levels—to longitudinal structural neuroimaging measures of cortical gray matter thickness. We included a total of 792 magnetic resonance imaging brain scans, acquired between ages 9 and 22 years from patients with childhood-onset schizophrenia (COS), their non-psychotic full siblings, and matched healthy controls. Whereas greater Val allele dose (which confers enhanced dopamine catabolism and is proposed to aggravate cortical deficits in schizophrenia) accelerated adolescent cortical thinning in both schizophrenia probands and their siblings, it attenuated cortical thinning in healthy controls. This similarity between COS patients and their siblings was accompanied by differences between the two groups in the timing and spatial distribution of disrupted COMT influences on cortical maturation. Consequently, whereas greater Val “dose” conferred persistent dorsolateral prefrontal cortical deficits amongst affected probands by adulthood, cortical thickness differences associated with varying Val dose in non-psychotic siblings resolved over the age-range studied. These findings suggest that cortical abnormalities in pedigrees affected by schizophrenia may be contributed to by a disruption of dopaminergic infleunces on cortical maturation. PMID:21620981

Influence of COMT genotype and affective distractors on the processing of self-generated thought.

PubMed

Kilford, Emma J; Dumontheil, Iroise; Wood, Nicholas W; Blakemore, Sarah-Jayne

2015-06-01

The catechol-O-methyltransferase (COMT) enzyme is a major determinant of prefrontal dopamine levels. The Val(158)Met polymorphism affects COMT enzymatic activity and has been associated with variation in executive function and affective processing. This study investigated the effect of COMT genotype on the flexible modulation of the balance between processing self-generated and processing stimulus-oriented information, in the presence or absence of affective distractors. Analyses included 124 healthy adult participants, who were also assessed on standard working memory (WM) tasks. Relative to Val carriers, Met homozygotes made fewer errors when selecting and manipulating self-generated thoughts. This effect was partly accounted for by an association between COMT genotype and visuospatial WM performance. We also observed a complex interaction between the influence of affective distractors, COMT genotype and sex on task accuracy: male, but not female, participants showed a sensitivity to the affective distractors that was dependent on COMT genotype. This was not accounted for by WM performance. This study provides novel evidence of the role of dopaminergic genetic variation on the ability to select and manipulate self-generated thoughts. The results also suggest sexually dimorphic effects of COMT genotype on the influence of affective distractors on executive function. © The Author (2014). Published by Oxford University Press.

Initial evidence that polymorphisms in neurotransmitter-regulating genes contribute to being born small for gestational age

PubMed Central

Morgan, Angharad R.; Thompson, John M.D.; Waldie, Karen E.; Cornforth, Christine M.; Turic, Darko; Sonuga-Barke, Edmund J.S.; Lam, Wen-Jiun; Ferguson, Lynnette R.; Mitchell, Edwin A.

2012-01-01

Being born small for gestational age (SGA) is a putative risk factor for the development of later cognitive and psychiatric health problems. While the inter-uterine environment has been shown to play an important role in predicting birth weight, little is known about the genetic factors that might be important. Here we test the hypothesis that neurotransmitter-regulating genes implicated in psychiatric disorders previously shown to be associated with SGA (such as attention-deficit hyperactivity disorder) are themselves predictive of SGA. DNA was collected from 227 SGA and 319 appropriate for gestational age children taking part in the Auckland Birthweight Collaborative Study. Candidate single nucleotide polymorphisms in genes regulating activity within dopamine, serotonin, glutamate and gamma-aminobutyric acid pathways were genotyped. Multiple regression analysis, controlling for potentially confounding factors, supported nominally significant associations between SGA and single nucleotide polymorphisms in COMT, HTR2A, SLC1A1 and SLC6A1. This is the first evidence that genes implicated in psychiatric disorders previously linked to SGA status themselves predict SGA. This highlights the possibility that the link between SGA and psychiatric disorders such as attention-deficit hyperactivity disorder may in part be genetically determined – that SGA marks pre-existing genetic risk for later problems. PMID:27625810

Physical and verbal aggressive behavior and COMT genotype: Sensitivity to the environment.

PubMed

Tuvblad, Catherine; Narusyte, Jurgita; Comasco, Erika; Andershed, Henrik; Andershed, Anna-Karin; Colins, Olivier F; Fanti, Kostas A; Nilsson, Kent W

2016-07-01

Catechol-O-methyltransferase (COMT) genotype has been implicated as a vulnerability factor for several psychiatric diseases as well as aggressive behavior, either directly, or in interaction with an adverse environment. The present study aimed at investigating the susceptibility properties of COMT genotype to adverse and favorable environment in relation to physical and verbal aggressive behavior. The COMT Val158Met polymorphism was genotyped in a Swedish population-based cohort including 1,783 individuals, ages 20-24 years (47% males). A significant three-way interaction was found, after correction for multiple testing, between COMT genotype, exposure to violence, and parent-child relationship in association with physical but not verbal aggressive behavior. Homozygous for the Val allele reported lower levels of physical aggressive behavior when they were exposed to violence and at the same time experienced a positive parent-child relationship compared to Met carriers. Thus, susceptibility properties of COMT genotype were observed in relation to physical aggressive behavior supporting the hypothesis that COMT genotypes are modifying the sensitivity to environment that confers either risk or protection for aggressive behavior. As these are novel findings, they warrant further investigation and replication in independent samples. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

Right secondary somatosensory cortex-a promising novel target for the treatment of drug-resistant neuropathic orofacial pain with repetitive transcranial magnetic stimulation.

PubMed

Lindholm, Pauliina; Lamusuo, Salla; Taiminen, Tero; Pesonen, Ullamari; Lahti, Ari; Virtanen, Arja; Forssell, Heli; Hietala, Jarmo; Hagelberg, Nora; Pertovaara, Antti; Parkkola, Riitta; Jääskeläinen, Satu

2015-07-01

High-frequency repetitive transcranial magnetic stimulation (rTMS) of the motor cortex has analgesic effect; however, the efficacy of other cortical targets and the mode of action remain unclear. We examined the effects of rTMS in neuropathic orofacial pain, and compared 2 cortical targets against placebo. Furthermore, as dopaminergic mechanisms modulate pain responses, we assessed the influence of the functional DRD2 gene polymorphism (957C>T) and the catechol-O-methyltransferase (COMT) Val158Met polymorphism on the analgesic effect of rTMS. Sixteen patients with chronic drug-resistant neuropathic orofacial pain participated in this randomized, placebo-controlled, crossover study. Navigated high-frequency rTMS was given to the sensorimotor (S1/M1) and the right secondary somatosensory (S2) cortices. All subjects were genotyped for the DRD2 957C>T and COMT Val158Met polymorphisms. Pain, mood, and quality of life were monitored throughout the study. The numerical rating scale pain scores were significantly lower after the S2 stimulation than after the S1/M1 (P = 0.0071) or the sham (P = 0.0187) stimulations. The Brief Pain Inventory scores were also lower 3 to 5 days after the S2 stimulation than those at pretreatment baseline (P = 0.0127 for the intensity of pain and P = 0.0074 for the interference of pain) or after the S1/M1 (P = 0.001 and P = 0.0001) and sham (P = 0.0491 and P = 0.0359) stimulations. No correlations were found between the genetic polymorphisms and the analgesic effect in the present small clinical sample. The right S2 cortex is a promising new target for the treatment of neuropathic orofacial pain with high-frequency rTMS.

No Association of BDNF, COMT, MAOA, SLC6A3, and SLC6A4 Genes and Depressive Symptoms in a Sample of Healthy Colombian Subjects.

PubMed

González-Giraldo, Yeimy; Camargo, Andrés; López-León, Sandra; Forero, Diego A

2015-01-01

Background. Major depressive disorder (MDD) is the second cause of years lived with disability around the world. A large number of studies have been carried out to identify genetic risk factors for MDD and related endophenotypes, mainly in populations of European and Asian descent, with conflicting results. The main aim of the current study was to analyze the possible association of five candidate genes and depressive symptoms in a Colombian sample of healthy subjects. Methods and Materials. The Spanish adaptation of the Hospital Anxiety and Depression Scale (HADS) was applied to one hundred eighty-eight healthy Colombian subjects. Five functional polymorphisms were genotyped using PCR-based assays: BDNF-Val66Met (rs6265), COMT-Val158Met (rs4680), SLC6A4-HTTLPR (rs4795541), MAOA-uVNTR, and SLC6A3-VNTR (rs28363170). Result. We did not find significant associations with scores of depressive symptoms, derived from the HADS, for any of the five candidate genes (nominal p values >0.05). In addition, we did not find evidence of significant gene-gene interactions. Conclusion. This work is one of the first studies of candidate genes for depressive symptoms in a Latin American sample. Study of additional genetic and epigenetic variants, taking into account other pathophysiological theories, will help to identify novel candidates for MDD in populations around the world.

[The effect of the serotonin transporter 5-HTTLPR polymorphism on the recognition of facial emotions in schizophrenia].

PubMed

Alfimova, M V; Golimbet, V E; Korovaitseva, G I; Lezheiko, T V; Abramova, L I; Aksenova, E V; Bolgov, M I

2014-01-01

The 5-HTTLPR SLC6A4 and catechol-o-methyltransferase (COMT) Val158Met polymorphisms are reported to be associated with processing of facial expressions in general population. Impaired recognition of facial expressions that is characteristic of schizophrenia negatively impacts on the social adaptation of the patients. To search for molecular mechanisms of this deficit, we studied main and epistatic effects of 5-HTTLPR and Val158Met polymorphisms on the facial emotion recognition in patients with schizophrenia (n=299) and healthy controls (n=232). The 5-HTTLPR polymorphism was associated with the emotion recognition in patients. The ll-homozygotes recognized facial emotions significantly better compared to those with an s-allele (F=8.00; p=0.005). Although the recognition of facial emotions was correlated with negative symptoms, verbal learning and trait anxiety, these variables did not significantly modified the association. In both groups, no effect of the COMT on the recognition of facial emotions was found.

Catechol-O-methyltransferase (COMT) genotype biases neural correlates of empathy and perceived personal distress in schizophrenia.

PubMed

Poletti, Sara; Radaelli, Daniele; Cavallaro, Roberto; Bosia, Marta; Lorenzi, Cristina; Pirovano, Adele; Smeraldi, Enrico; Benedetti, Francesco

2013-02-01

The catechol-O-methyltransferase (COMT) Val(108/158)Met polymorphism (rs4680) influences enzyme activity with valine (Val) allele associated with higher enzymatic activity. Several studies suggest that factors influencing dopaminergic transmission could control response to stressful situations. Empathy is an essential element of human behavior, requires the ability to adopt another person's perspective, and has been found to be dysfunctional in schizophrenia. Twenty-eight schizophrenic patients underwent functional magnetic resonance imaging performing an empathy task. Perceived empathy has been evaluated with the Interpersonal Reactivity Index. An effect of COMT on perceived distress subscale has been shown, with methionine (Met)/Met subjects reporting lower rates of stress compared with Val/Val. Moreover, imaging results showed an effect of genotype on empathy processing in the anterior cingulate with Val/Val subjects showing the lowest activation. This is the first study of the effect of rs4680 on interpersonal distress and neural correlates of empathy in schizophrenia. We found a decrease in neural responses in areas that ensure a cognitive control of emotion that is paralleled by perceived distress in interpersonal situation; this functional pattern seems to be influenced by rs4680 COMT polymorphism. Copyright © 2013 Elsevier Inc. All rights reserved.

COMT Val158Met Polymorphism, Executive Dysfunction, and Sexual Risk Behavior in the Context of HIV Infection and Methamphetamine Dependence

PubMed Central

Bousman, C. A.; Cherner, M.; Atkinson, J. H.; Heaton, R. K.; Grant, I.; Everall, I. P.; HNRC Group, The

2010-01-01

Catechol-O-methyltransferease (COMT) metabolizes prefrontal cortex dopamine (DA), a neurotransmitter involved in executive behavior; the Val158Met genotype has been linked to executive dysfunction, which might increase sexual risk behaviors favoring HIV transmission. Main and interaction effects of COMT genotype and executive functioning on sexual risk behavior were examined. 192 sexually active nonmonogamous men completed a sexual behavior questionnaire, executive functioning tests, and were genotyped using blood-derived DNA. Main effects for executive dysfunction but not COMT on number of sexual partners were observed. A COMT x executive dysfunction interaction was found for number of sexual partners and insertive anal sex, significant for carriers of the Met/Met and to a lesser extent Val/Met genotypes but not Val/Val carriers. In the context of HIV and methamphetamine dependence, dopaminergic overactivity in prefrontal cortex conferred by the Met/Met genotype appears to result in a liability for executive dysfunction and potentially associated risky sexual behavior. PMID:20069120

Genetic and vascular modifiers of age-sensitive cognitive skills: effects of COMT, BDNF, ApoE, and hypertension.

PubMed

Raz, Naftali; Rodrigue, Karen M; Kennedy, Kristen M; Land, Susan

2009-01-01

Several single nucleotide polymorphisms have been linked to neural and cognitive variation in healthy adults. We examined contribution of three polymorphisms frequently associated with individual differences in cognition (Catechol-O-Methyl-Transferase Val158Met, Brain-Derived-Neurotrophic-Factor Val66Met, and Apolipoprotein E epsilon4) and a vascular risk factor (hypertension) in a sample of 189 volunteers (age 18-82). Genotypes were determined from buccal culture samples, and cognitive performance was assessed in 4 age-sensitive domains?fluid intelligence, executive function (inhibition), associative memory, and processing speed. We found that younger age and COMT Met/Met genotype, associated with low COMT activity and higher prefrontal dopamine content, were independently linked to better performance in most of the tested domains. Homozygotes for Val allele of BDNF polymorphism exhibited better associative memory and faster speed of processing than the Met allele carriers, with greater effect for women and persons with hypertension. Carriers of ApoE epsilon4 allele evidenced steeper age-related increase in costs of Stroop color interference, but showed no negative effects on memory. The findings indicate that age-related cognitive performance is differentially affected by distinct genetic factors and their interactions with vascular health status. (c) 2009 APA, all rights reserved.

Catechol-O-Methyltransferase Val158Met Polymorphism Associates with Individual Differences in Sleep Physiologic Responses to Chronic Sleep Loss

PubMed Central

Goel, Namni; Banks, Siobhan; Lin, Ling; Mignot, Emmanuel; Dinges, David F.

2011-01-01

Background The COMT Val158Met polymorphism modulates cortical dopaminergic catabolism, and predicts individual differences in prefrontal executive functioning in healthy adults and schizophrenic patients, and associates with EEG differences during sleep loss. We assessed whether the COMT Val158Met polymorphism was a novel marker in healthy adults of differential vulnerability to chronic partial sleep deprivation (PSD), a condition distinct from total sleep loss and one experienced by millions on a daily and persistent basis. Methodology/Principal Findings 20 Met/Met, 64 Val/Met, and 45 Val/Val subjects participated in a protocol of two baseline 10h time in bed (TIB) nights followed by five consecutive 4 h TIB nights. Met/Met subjects showed differentially steeper declines in non-REM EEG slow-wave energy (SWE)—the putative homeostatic marker of sleep drive—during PSD, despite comparable baseline SWE declines. Val/Val subjects showed differentially smaller increases in slow-wave sleep and smaller reductions in stage 2 sleep during PSD, and had more stage 1 sleep across nights and a shorter baseline REM sleep latency. The genotypes, however, did not differ in performance across various executive function and cognitive tasks and showed comparable increases in subjective and physiological sleepiness in response to chronic sleep loss. Met/Met genotypic and Met allelic frequencies were higher in whites than African Americans. Conclusions/Significance The COMT Val158Met polymorphism may be a genetic biomarker for predicting individual differences in sleep physiology—but not in cognitive and executive functioning—resulting from sleep loss in a healthy, racially-diverse adult population of men and women. Beyond healthy sleepers, our results may also provide insight for predicting sleep loss responses in patients with schizophrenia and other psychiatric disorders, since these groups repeatedly experience chronically-curtailed sleep and demonstrate COMT-related treatment responses and risk factors for symptom exacerbation. PMID:22216231

Music genetics research: Association with musicality of a polymorphism in the AVPR1A gene.

PubMed

Mariath, Luiza Monteavaro; Silva, Alexandre Mauat da; Kowalski, Thayne Woycinck; Gattino, Gustavo Schulz; Araujo, Gustavo Andrade de; Figueiredo, Felipe Grahl; Tagliani-Ribeiro, Alice; Roman, Tatiana; Vianna, Fernanda Sales Luiz; Schuler-Faccini, Lavínia; Schuch, Jaqueline Bohrer

2017-01-01

Musicality is defined as a natural tendency, sensibility, knowledge, or talent to create, perceive, and play music. Musical abilities involve a great range of social and cognitive behaviors, which are influenced by both environmental and genetic factors. Although a number of studies have yielded insights into music genetics research, genes and biological pathways related to these traits are not fully understood. Our hypothesis in the current study is that genes associated with different behaviors could also influence the musical phenotype. Our aim was to investigate whether polymorphisms in six genes (AVPR1A, SLC6A4, ITGB3, COMT, DRD2 and DRD4) related to social and cognitive traits are associated with musicality in a sample of children. Musicality was assessed through an individualized music therapy assessment profile (IMTAP) which has been validated in Brazil to measure musical ability. We show here that the RS1 microsatellite of the AVPR1A gene is nominally associated with musicality, corroborating previous results linking AVPR1A with musical activity. This study is one of the first to investigate musicality in a comprehensive way, and it contributes to better understand the genetic basis underlying musical ability.

Music genetics research: Association with musicality of a polymorphism in the AVPR1A gene

PubMed Central

Mariath, Luiza Monteavaro; da Silva, Alexandre Mauat; Kowalski, Thayne Woycinck; Gattino, Gustavo Schulz; de Araujo, Gustavo Andrade; Figueiredo, Felipe Grahl; Tagliani-Ribeiro, Alice; Roman, Tatiana; Vianna, Fernanda Sales Luiz; Schuler-Faccini, Lavínia; Schuch, Jaqueline Bohrer

2017-01-01

Abstract Musicality is defined as a natural tendency, sensibility, knowledge, or talent to create, perceive, and play music. Musical abilities involve a great range of social and cognitive behaviors, which are influenced by both environmental and genetic factors. Although a number of studies have yielded insights into music genetics research, genes and biological pathways related to these traits are not fully understood. Our hypothesis in the current study is that genes associated with different behaviors could also influence the musical phenotype. Our aim was to investigate whether polymorphisms in six genes (AVPR1A, SLC6A4, ITGB3, COMT, DRD2 and DRD4) related to social and cognitive traits are associated with musicality in a sample of children. Musicality was assessed through an individualized music therapy assessment profile (IMTAP) which has been validated in Brazil to measure musical ability. We show here that the RS1 microsatellite of the AVPR1A gene is nominally associated with musicality, corroborating previous results linking AVPR1A with musical activity. This study is one of the first to investigate musicality in a comprehensive way, and it contributes to better understand the genetic basis underlying musical ability. PMID:28534928

The role of histamine degradation gene polymorphisms in moderating the effects of food additives on children's ADHD symptoms.

PubMed

Stevenson, Jim; Sonuga-Barke, Edmund; McCann, Donna; Grimshaw, Kate; Parker, Karen M; Rose-Zerilli, Matthew J; Holloway, John W; Warner, John O

2010-09-01

Food additives can exacerbate ADHD symptoms and cause non-immunoglobulin E-dependent histamine release from circulating basophils. However, children vary in the extent to which their ADHD symptoms are exacerbated by the ingestion of food additives. The authors hypothesized that genetic polymorphisms affecting histamine degradation would explain the diversity of responses to additives. In a double-blind, placebo-controlled crossover trial, challenges involving two food color additive and sodium benzoate (preservative) mixtures in a fruit drink were administered to a general community sample of 3-year-old children (N = 153) and 8/9-year-old children (N = 144). An aggregate ADHD symptom measure (based on teacher and parent blind ratings of behavior, blind direct observation of behavior in the classroom, and--for 8/9-year-old children only--a computerized measure of attention) was the main outcome variable. The adverse effect of food additives on ADHD symptoms was moderated by histamine degradation gene polymorphisms HNMT T939C and HNMT Thr105Ile in 3- and 8/9-year-old children and by a DAT1 polymorphism (short versus long) in 8/9-year-old children only. There was no evidence that polymorphisms in catecholamine genes COMT Val108Met, ADRA2A C1291G, and DRD4-rs7403703 moderated the effect on ADHD symptoms. Histamine may mediate the effects of food additives on ADHD symptoms, and variations in genes influencing the action of histamine may explain the inconsistency between previous studies. Genes influencing a range of neurotransmitter systems and their interplay with environmental factors, such as diet, need to be examined to understand genetic influences on ADHD symptoms.

Effects of sex and COMT genotype on environmentally modulated cognitive control in mice

PubMed Central

Papaleo, Francesco; Erickson, Lucy; Liu, Guangping; Chen, Jingshan; Weinberger, Daniel R.

2012-01-01

Cognitive functioning differs between males and females, likely in part related to genetic dimorphisms. An example of a common genetic variation reported to have sexually dimorphic effects on cognition and temperament in humans is the Val/Met polymorphism in catechol-O-methyltransferase (COMT). We tested male and female wild-type mice (+/+) and their COMT knockout littermates (+/− and −/−) in the five-choice serial reaction time task (5CSRTT) to investigate the effects of sex, COMT genotype, and their interactions with environmental manipulations of cognitive functions such as attention, impulsivity, compulsivity, motivation, and rule-reversal learning. No sex- or COMT-dependent differences were present in the basic acquisition of the five-choice serial reaction time task. In contrast, specific environmental manipulations revealed a variety of sex- and COMT-dependent effects. Following an experimental change to trigger impulsive responding, the sexes showed similar increases in impulsiveness, but males eventually habituated whereas females did not. Moreover, COMT knockout mice were more impulsive compared with wild-type littermates. Manipulations involving mild stress adversely affected cognitive performance in males, and particularly COMT knockout males, but not in females. In contrast, following amphetamine treatment, subtle sex by genotype and sex by treatment interactions emerged primarily limited to compulsive behavior. After repeated testing, female mice showed improved performance, working harder and eventually outperforming males. Finally, removing the food-restriction condition enhanced sex and COMT differences, revealing that overall, females outperform males and COMT knockout males outperform their wild-type littermates. These findings illuminate complex sex- and COMT-related effects and their interactions with environmental factors to influence specific executive cognitive domains. PMID:23169629

Glucocorticoid Receptors, Brain-Derived Neurotrophic Factor, Serotonin and Dopamine Neurotransmission are Associated with Interferon-Induced Depression

PubMed Central

Udina, M; Navinés, R; Egmond, E; Oriolo, G; Langohr, K; Gimenez, D; Valdés, M; Gómez-Gil, E; Grande, I; Gratacós, M; Kapczinski, F; Artigas, F; Vieta, E; Solà, R

2016-01-01

Background: The role of inflammation in mood disorders has received increased attention. There is substantial evidence that cytokine therapies, such as interferon alpha (IFN-alpha), can induce depressive symptoms. Indeed, proinflammatory cytokines change brain function in several ways, such as altering neurotransmitters, the glucocorticoid axis, and apoptotic mechanisms. This study aimed to evaluate the impact on mood of initiating IFN-alpha and ribavirin treatment in a cohort of patients with chronic hepatitis C. We investigated clinical, personality, and functional genetic variants associated with cytokine-induced depression. Methods: We recruited 344 Caucasian outpatients with chronic hepatitis C, initiating IFN-alpha and ribavirin therapy. All patients were euthymic at baseline according to DSM-IV-R criteria. Patients were assessed at baseline and 4, 12, 24, and 48 weeks after treatment initiation using the Patient Health Questionnaire (PHQ), the Hospital Anxiety and Depression Scale (HADS), and the Temperament and Character Inventory (TCI). We genotyped several functional polymorphisms of interleukin-28 (IL28B), indoleamine 2,3-dioxygenase (IDO-1), serotonin receptor-1A (HTR1A), catechol-O-methyl transferase (COMT), glucocorticoid receptors (GCR1 and GCR2), brain-derived neurotrophic factor (BDNF), and FK506 binding protein 5 (FKBP5) genes. A survival analysis was performed, and the Cox proportional hazards model was used for the multivariate analysis. Results: The cumulative incidence of depression was 0.35 at week 24 and 0.46 at week 48. The genotypic distributions were in Hardy-Weinberg equilibrium. Older age (p = 0.018, hazard ratio [HR] per 5 years = 1.21), presence of depression history (p = 0.0001, HR = 2.38), and subthreshold depressive symptoms at baseline (p = 0.005, HR = 1.13) increased the risk of IFN-induced depression. So too did TCI personality traits, with high scores on fatigability (p = 0.0037, HR = 1.17), impulsiveness (p = 0.0200 HR = 1.14), disorderliness (p = 0.0339, HR = 1.11), and low scores on extravagance (p = 0.0040, HR = 0.85). An interaction between HTR1A and COMT genes was found. Patients carrying the G allele of HTR1A plus the Met substitution of the COMT polymorphism had a greater risk for depression during antiviral treatment (HR = 3.83) than patients with the CC (HTR1A) and Met allele (COMT) genotypes. Patients carrying the HTR1A CC genotype and the COMT Val/Val genotype (HR = 3.25) had a higher risk of depression than patients with the G allele (HTR1A) and the Val/Val genotype. Moreover, functional variants of the GCR1 (GG genotype: p = 0.0436, HR = 1.88) and BDNF genes (Val/Val genotype: p = 0.0453, HR = 0.55) were associated with depression. Conclusions: The results of the study support the theory that IFN-induced depression is associated with a complex pathophysiological background, including serotonergic and dopaminergic neurotransmission as well as glucocorticoid and neurotrophic factors. These findings may help to improve the management of patients on antiviral treatment and broaden our understanding of the pathogenesis of mood disorders. PMID:26721949

Genetic variants and early cigarette smoking and nicotine dependence phenotypes in adolescents.

PubMed

O'Loughlin, Jennifer; Sylvestre, Marie-Pierre; Labbe, Aurélie; Low, Nancy C; Roy-Gagnon, Marie-Hélène; Dugas, Erika N; Karp, Igor; Engert, James C

2014-01-01

While the heritability of cigarette smoking and nicotine dependence (ND) is well-documented, the contribution of specific genetic variants to specific phenotypes has not been closely examined. The objectives of this study were to test the associations between 321 tagging single-nucleotide polymorphisms (SNPs) that capture common genetic variation in 24 genes, and early smoking and ND phenotypes in novice adolescent smokers, and to assess if genetic predictors differ across these phenotypes. In a prospective study of 1294 adolescents aged 12-13 years recruited from ten Montreal-area secondary schools, 544 participants who had smoked at least once during the 7-8 year follow-up provided DNA. 321 single-nucleotide polymorphisms (SNPs) in 24 candidate genes were tested for an association with number of cigarettes smoked in the past 3 months, and with five ND phenotypes (a modified version of the Fagerstrom Tolerance Questionnaire, the ICD-10 and three clusters of ND symptoms representing withdrawal symptoms, use of nicotine for self-medication, and a general ND/craving symptom indicator). The pattern of SNP-gene associations differed across phenotypes. Sixteen SNPs in seven genes (ANKK1, CHRNA7, DDC, DRD2, COMT, OPRM1, SLC6A3 (also known as DAT1)) were associated with at least one phenotype with a p-value <0.01 using linear mixed models. After permutation and FDR adjustment, none of the associations remained statistically significant, although the p-values for the association between rs557748 in OPRM1 and the ND/craving and self-medication phenotypes were both 0.076. Because the genetic predictors differ, specific cigarette smoking and ND phenotypes should be distinguished in genetic studies in adolescents. Fifteen of the 16 top-ranked SNPs identified in this study were from loci involved in dopaminergic pathways (ANKK1/DRD2, DDC, COMT, OPRM1, and SLC6A3). Dopaminergic pathways may be salient during early smoking and the development of ND.

Prediction of remission of depression with clinical variables, neuropsychological performance, and serotonergic/dopaminergic gene polymorphisms.

PubMed

Gudayol-Ferré, Esteve; Herrera-Guzmán, Ixchel; Camarena, Beatriz; Cortés-Penagos, Carlos; Herrera-Abarca, Jorge E; Martínez-Medina, Patricia; Asbun-Bojalil, Juan; Lira-Islas, Yuridia; Reyes-Ponce, Celia; Guàrdia-Olmos, Joan

2012-11-01

The aim of our work is to study the possible role of clinical variables, neuropsychological performance, and the 5HTTLPR, rs25531, and val108/58Met COMT polymorphisms on the prediction of depression remission after 12 weeks' treatment with fluoxetine. These variables have been studied as potential predictors of depression remission, but they present poor prognostic sensitivity and specificity by themselves. Seventy-two depressed patients were genotyped according to the aforementioned polymorphisms and were clinically and neuropsychologically assessed before a 12-week fluxetine treatment. Only the La allele of rs25531 polymorphism and the GG and AA forms of the val 108/158 Met polymorphism predict major depressive disorder remission after 12 weeks' treatment with fluoxetine. None of the clinical and neuropsychological variables studied predicted remission. Our results suggest that clinical and neuropsychological variables can initially predict early response to fluoxetine and mask the predictive role of genetic variables; but in remission, where clinical and neuropsychological symptoms associated with depression tend to disappear thanks to the treatment administered, the polymorphisms studied are the only variables in our model capable of predicting remission. However, placebo effects that are difficult to control require cautious interpretation of the results.

The role of catechol-O-methyltransferase in catechol-enhanced erythroid differentiation of K562 cells

DOE Office of Scientific and Technical Information (OSTI.GOV)

Suriguga,; Li, Xiao-Fei; Li, Yang

2013-12-15

Catechol is widely used in pharmaceutical and chemical industries. Catechol is also one of phenolic metabolites of benzene in vivo. Our previous study showed that catechol improved erythroid differentiation potency of K562 cells, which was associated with decreased DNA methylation in erythroid specific genes. Catechol is a substrate for the catechol-O-methyltransferase (COMT)-mediated methylation. In the present study, the role of COMT in catechol-enhanced erythroid differentiation of K562 cells was investigated. Benzidine staining showed that exposure to catechol enhanced hemin-induced hemoglobin accumulation and induced mRNA expression of erythroid specific genes in K562 cells. Treatment with catechol caused a time- and concentration-dependentmore » increase in guaiacol concentration in the medium of cultured K562 cells. When COMT expression was knocked down by COMT shRNA expression in K562 cells, the production of guaiacol significantly reduced, and the sensitivity of K562 cells to cytotoxicity of catechol significantly increased. Knockdown of COMT expression by COMT shRNA expression also eliminated catechol-enhanced erythroid differentiation of K562 cells. In addition, the pre-treatment with methyl donor S-adenosyl-L-methionine or its demethylated product S-adenosyl-L-homocysteine induced a significant increase in hemin-induced Hb synthesis in K562 cells and the mRNA expression of erythroid specific genes. These findings indicated that O-methylation catalyzed by COMT acted as detoxication of catechol and involved in catechol-enhanced erythroid differentiation of K562 cells, and the production of S-adenosyl-L-homocysteine partly explained catechol-enhanced erythroid differentiation. - Highlights: • Catechol enhanced hemin-induced hemoglobin accumulation. • COMT-catalyzed methylation acted as detoxication of catechol. • COMT involved in catechol-enhanced erythroid differentiation.« less

Psychosis-inducing effects of cannabis are related to both childhood abuse and COMT genotypes.

PubMed

Alemany, S; Arias, B; Fatjó-Vilas, M; Villa, H; Moya, J; Ibáñez, M I; Ortet, G; Gastó, C; Fañanás, L

2014-01-01

To test whether the association between childhood abuse, cannabis use and psychotic experiences (PEs) was moderated by the COMT (catechol-O-methyltransferase) gene. Psychotic experiences (PEs), childhood abuse, cannabis use and COMT Val158Met genotypes were assessed in 533 individuals from the general population. Data were analysed hierarchically by means of multiple linear regression models. Childhood abuse showed a significant main effect on both positive (β = 0.09; SE = 0.04; P = 0.047) and negative PEs (β = 0.11; SE = 0.05; P = 0.038). A significant three-way interaction effect was found among childhood abuse, cannabis use and the COMT gene on positive PEs (β = -0.30; SE = 0.11; P = 0.006). This result suggests that COMT genotypes and cannabis use only influenced PE scores among individuals exposed to childhood abuse. Furthermore, exposure to childhood abuse and cannabis use increased PE scores in Val carriers. However, in individuals exposed to childhood abuse but who did not use cannabis, PEs increased as a function of the Met allele copies of the COMT gene. Cannabis use after exposure to childhood abuse may have opposite effects on the risk of PEs, depending on the COMT genotypes providing evidence for a qualitative interaction. Val carriers exposed to childhood abuse are vulnerable to the psychosis-inducing effects of cannabis. © 2013 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Clinical pharmacology of 3,4-methylenedioxymethamphetamine (MDMA, "ecstasy"): the influence of gender and genetics (CYP2D6, COMT, 5-HTT).

PubMed

Pardo-Lozano, Ricardo; Farré, Magí; Yubero-Lahoz, Samanta; O'Mathúna, Brian; Torrens, Marta; Mustata, Cristina; Pérez-Mañá, Clara; Langohr, Klaus; Cuyàs, Elisabet; Carbó, Marcel lí; de la Torre, Rafael

2012-01-01

The synthetic psychostimulant MDMA (± 3,4-methylenedioxymethamphetamine, ecstasy) acts as an indirect serotonin, dopamine, and norepinephrine agonist and as a mechanism-based inhibitor of the cytochrome P-450 2D6 (CYP2D6). It has been suggested that women are more sensitive to MDMA effects than men but no clinical experimental studies have satisfactorily evaluated the factors contributing to such observations. There are no studies evaluating the influence of genetic polymorphism on the pharmacokinetics (CYP2D6; catechol-O-methyltransferase, COMT) and pharmacological effects of MDMA (serotonin transporter, 5-HTT; COMT). This clinical study was designed to evaluate the pharmacokinetics and physiological and subjective effects of MDMA considering gender and the genetic polymorphisms of CYP2D6, COMT, and 5-HTT. A total of 27 (12 women) healthy, recreational users of ecstasy were included (all extensive metabolizers for CYP2D6). A single oral weight-adjusted dose of MDMA was administered (1.4 mg/kg, range 75-100 mg) which was similar to recreational doses. None of the women were taking oral contraceptives and the experimental session was performed during the early follicular phase of their menstrual cycle. Principal findings show that subjects reached similar MDMA plasma concentrations, and experienced similar positive effects, irrespective of gender or CYP2D6 (not taking into consideration poor or ultra-rapid metabolizers) or COMT genotypes. However, HMMA plasma concentrations were linked to CYP2D6 genotype (higher with two functional alleles). Female subjects displayed more intense physiological (heart rate, and oral temperature) and negative effects (dizziness, sedation, depression, and psychotic symptoms). Genotypes of COMT val158met or 5-HTTLPR with high functionality (val/val or l/*) determined greater cardiovascular effects, and with low functionality (met/* or s/s) negative subjective effects (dizziness, anxiety, sedation). In conclusion, the contribution of MDMA pharmacokinetics following 1.4 mg/kg MDMA to the gender differences observed in drug effects appears to be negligible or even null. In contrast, 5-HTTLPR and COMT val158met genotypes play a major role. ClinicalTrials.gov NCT01447472.

Clinical Pharmacology of 3,4-Methylenedioxymethamphetamine (MDMA, “Ecstasy”): The Influence of Gender and Genetics (CYP2D6, COMT, 5-HTT)

PubMed Central

O’Mathúna, Brian; Torrens, Marta; Mustata, Cristina; Pérez-Mañá, Clara; Langohr, Klaus; Cuyàs, Elisabet; Carbó, Marcel·lí; de la Torre, Rafael

2012-01-01

The synthetic psychostimulant MDMA (±3,4-methylenedioxymethamphetamine, ecstasy) acts as an indirect serotonin, dopamine, and norepinephrine agonist and as a mechanism-based inhibitor of the cytochrome P-450 2D6 (CYP2D6). It has been suggested that women are more sensitive to MDMA effects than men but no clinical experimental studies have satisfactorily evaluated the factors contributing to such observations. There are no studies evaluating the influence of genetic polymorphism on the pharmacokinetics (CYP2D6; catechol-O-methyltransferase, COMT) and pharmacological effects of MDMA (serotonin transporter, 5-HTT; COMT). This clinical study was designed to evaluate the pharmacokinetics and physiological and subjective effects of MDMA considering gender and the genetic polymorphisms of CYP2D6, COMT, and 5-HTT. A total of 27 (12 women) healthy, recreational users of ecstasy were included (all extensive metabolizers for CYP2D6). A single oral weight-adjusted dose of MDMA was administered (1.4 mg/kg, range 75–100 mg) which was similar to recreational doses. None of the women were taking oral contraceptives and the experimental session was performed during the early follicular phase of their menstrual cycle. Principal findings show that subjects reached similar MDMA plasma concentrations, and experienced similar positive effects, irrespective of gender or CYP2D6 (not taking into consideration poor or ultra-rapid metabolizers) or COMT genotypes. However, HMMA plasma concentrations were linked to CYP2D6 genotype (higher with two functional alleles). Female subjects displayed more intense physiological (heart rate, and oral temperature) and negative effects (dizziness, sedation, depression, and psychotic symptoms). Genotypes of COMT val158met or 5-HTTLPR with high functionality (val/val or l/*) determined greater cardiovascular effects, and with low functionality (met/* or s/s) negative subjective effects (dizziness, anxiety, sedation). In conclusion, the contribution of MDMA pharmacokinetics following 1.4 mg/kg MDMA to the gender differences observed in drug effects appears to be negligible or even null. In contrast, 5-HTTLPR and COMT val158met genotypes play a major role. Trial Registration ClinicalTrials.gov NCT01447472 PMID:23112822

Differential Effects of the Catechol-O-Methyltransferase Val158Met Genotype on the Cognitive Function of Schizophrenia Patients and Healthy Japanese Individuals

PubMed Central

Tsuchimine, Shoko; Yasui-Furukori, Norio; Kaneda, Ayako; Kaneko, Sunao

2013-01-01

Background The functional polymorphism Val158Met in the catechol-O-methyltransferase (COMT) gene has been associated with differences in prefrontal cognitive functions in patients with schizophrenia and healthy individuals. Several studies have indicated that the Met allele is associated with better performance on measures of cognitive function. We investigated whether the COMT Val158Met genotype was associated with cognitive function in 149 healthy controls and 118 patients with schizophrenia. Methods Cognitive function, including verbal memory, working memory, motor speed, attention, executive function and verbal fluency, was assessed by the Brief Assessment of Cognition in Schizophrenia (BACS-J). We employed a one-way analysis of variance (ANOVA) and a multiple regression analysis to determine the associations between the COMT Val158Met genotype and the BACS-J measurements. Results The one-way ANOVA revealed a significant difference in the scores on the Tower of London, a measure of executive function, between the different Val158Met genotypes in the healthy controls (p = 0.023), and a post-hoc analysis showed significant differences between the scores on the Tower of London in the val/val genotype group (18.6 ± 2.4) compared to the other two groups (17.6 ± 2.7 for val/met and 17.1 ± 3.2 for met/met; p = 0.027 and p = 0.024, respectively). Multiple regression analyses revealed that executive function was significantly correlated with the Val158Met genotype (p = 0.003). However, no evidence was found for an effect of the COMT on any cognitive domains of the BACS-J in the patients with schizophrenia. Conclusion These data support the hypothesis that the COMT Val158Met genotype maintains an optimal level of dopamine activity. Further studies should be performed that include a larger sample size and include patients on and off medication, as these patients would help to confirm our findings. PMID:24282499

Perception of emotion in facial stimuli: The interaction of ADRA2A and COMT genotypes, and sex.

PubMed

Tamm, Gerly; Kreegipuu, Kairi; Harro, Jaanus

2016-01-04

Emotional facial stimuli are important social signals that are essential to be perceived and recognized in order to make appropriate decisions and responses in everyday communication. The ability to voluntarily guide attention to perceive and recognize emotions, and react to them varies largely across individuals, and has a strong genetic component (Friedman et al., 2008). Two key genetic variants of the catecholamine system that have been related to emotion perception and attention are the catechol-O-methyl transferase genetic variant (COMT Val158Met) and the α2A-receptor gene promoter polymorphism (ADRA2A C-1291G) accordingly. So far, the interaction of the two with sex in emotion perception has not been studied. Multilevel modeling method was applied to study how COMT Val158Met, ADRA2A C-1291G and sex are associated with measures of emotion perception in a large sample of young adults. Participants (n=506) completed emotion recognition and behavioral emotion detection tasks. It was found that COMT Val158Met genotype in combination with the ADRA2A C-1291G and sex predicts emotion detection, and perception of valence and arousal. In simple visual detection, the ADRA2A C-1291G G-allele leads to slower detection of a highly arousing face (scheming), which is modulated by each additional COMT Val158Met Met-allele and male sex predicting faster responses. The combination of G-allele, Met-allele and male sex also predicts higher perceived negativity in sad faces. No effects of C-1291G, Val158Met, and sex were found on verbal emotion recognition. Applying the findings to study the interplay between catecholamine-O-methyl transferase activity and α2A-receptors in emotion perception disorders (such as ADHD, autism and schizophrenia) in men and women would be the next step towards understanding individual differences in emotion perception. Copyright © 2015 Elsevier Inc. All rights reserved.

Inhibition of Comt with tolcapone slows progression of polycystic kidney disease in the more severely affected PKD/Mhm (cy/+) substrain of the Hannover Sprague-Dawley rat

PubMed Central

Boehn, Susanne N.E.; Spahn, Sonja; Neudecker, Sabine; Keppler, Andrea; Bihoreau, Marie-Thérèse; Kränzlin, Bettina; Pandey, Priyanka; Hoffmann, Sigrid C.; Li, Li; Torres, Vicente E.; Gröne, Hermann-Josef; Gretz, Norbert

2013-01-01

Background Autosomal dominant polycystic kidney disease (ADPKD) is one of the most common human inherited diseases. Modifier genes seem to modulate the disease progression and might therefore be promising drug targets. Although a number of modifier loci have been already identified, no modifier gene has been proven to be a real modifier yet. Methods Gene expression profiling of two substrains of the Han:SPRD rat, namely PKD/Mhm and PKD/US, both harboring the same mutation, was conducted in 36-day-old animals. Catechol-O-methyltransferase (Comt) was identified as a potential modifier gene. A 3-month treatment with tolcapone, a selective inhibitor of Comt, was carried out in PKD/Mhm and PKD/US (cy/+) animals. Results Comt is localized within a known modifier locus of PKD (MOP2). The enzyme encoding gene was found upregulated in the more severely affected PKD/Mhm substrain and was hence presumed to be a putative modifier gene of PKD. The treatment with tolcapone markedly attenuated the loss of renal function, inhibited renal enlargement, shifted the size distribution of renal cysts and retarded cell proliferation, apoptosis, inflammation and fibrosis development in affected (cy/+) male and female PKD/Mhm and PKD/US rats. Conclusions Comt has been confirmed to be the first reported modifier gene for PKD and tolcapone offers a promising drug for treating PKD. PMID:23543593

Genetic and Non-genetic Factors Associated With Constipation in Cancer Patients Receiving Opioids.

PubMed

Laugsand, Eivor A; Skorpen, Frank; Kaasa, Stein; Sabatowski, Rainer; Strasser, Florian; Fayers, Peter; Klepstad, Pål

2015-06-18

To examine whether the inter-individual variation in constipation among patients receiving opioids for cancer pain is associated with genetic or non-genetic factors. Cancer patients receiving opioids were included from 17 centers in 11 European countries. Intensity of constipation was reported by 1,568 patients on a four-point categorical scale. Non-genetic factors were included as covariates in stratified regression analyses on the association between constipation and 75 single-nucleotide polymorphisms (SNPs) within 15 candidate genes related to opioid- or constipation-signaling pathways (HTR3E, HTR4, HTR2A, TPH1, ADRA2A, CHRM3, TACR1, CCKAR, KIT, ARRB2, GHRL, ABCB1, COMT, OPRM1, and OPRD1). The non-genetic factors significantly associated with constipation were type of laxative, mobility and place of care among patients receiving laxatives (N=806), in addition to Karnofsky performance status and presence of metastases among patients not receiving laxatives (N=762) (P<0.01). Age, gender, body mass index, cancer diagnosis, time on opioids, opioid dose, and type of opioid did not contribute to the inter-individual differences in constipation. Five SNPs, rs1800532 in TPH1, rs1799971 in OPRM1, rs4437575 in ABCB1, rs10802789 in CHRM3, and rs2020917 in COMT were associated with constipation (P<0.01). Only rs2020917 in COMT passed the Benjamini-Hochberg criterion for a 10% false discovery rate. Type of laxative, mobility, hospitalization, Karnofsky performance status, presence of metastases, and five SNPs within TPH1, OPRM1, ABCB1, CHRM3, and COMT may contribute to the variability in constipation among cancer patients treated with opioids. Knowledge of these factors may help to develop new therapies and to identify patients needing a more individualized approach to treatment.

Catechol-O-methyltransferase association with hemoglobin A1c

PubMed Central

Hall, Kathryn T.; Jablonski, Kathleen A.; Chen, Ling; Harden, Maegan; Tolkin, Benjamin R.; Kaptchuk, Ted J.; Bray, George A.; Ridker, Paul M.; Florez, Jose C.; Chasman, Daniel I.

2016-01-01

Aims Catecholamines have metabolic effects on blood pressure, insulin sensitivity and blood glucose. Genetic variation in catechol-O-methyltransferase (COMT), an enzyme that degrades catecholamines, is associated with cardiometabolic risk factors and incident cardiovascular disease (CVD). Here we examined COMT effects on glycemic function and type 2 diabetes. Methods We tested whether COMT polymorphisms were associated with baseline HbA1c in the Women’s Genome Health Study (WGHS), and Meta-Analyses of Glucose and Insulin-related traits Consortium (MAGIC), and with susceptibility to type 2 diabetes in WGHS, DIAbetes Genetics Replication And Meta-analysis consortium (DIAGRAM), and the Diabetes Prevention Program (DPP). Given evidence that COMT modifies some drug responses, we examined association with type 2 diabetes and randomized metformin and aspirin treatment. Results COMT rs4680 high-activity G-allele was associated with lower HbA1c in WGHS (β = −0.032% [0.012], p = 0.008) and borderline significant in MAGIC (β = −0.006% [0.003], p = 0.07). Combined COMT per val allele effects on type 2 diabetes were significant (OR = 0.98 [0.96–0.998], p = 0.03) in fixed-effects analyses across WGHS, DIAGRAM, and DPP. Similar results were obtained for 2 other COMT SNPs rs4818 and rs4633. In the DPP, the rs4680 val allele was borderline associated with lower diabetes incidence among participants randomized to metformin (HR = 0.81 [0.65–1.00], p = 0.05). Conclusions COMT rs4680 high-activity G-allele was associated with lower HbA1c and modest protection from type 2 diabetes. The directionality of COMT associations was concordant with those previously observed for cardiometabolic risk factors and CVD. PMID:27282867

Genetic variation in catechol-O-methyltransferase modifies effects of clonidine treatment in chronic fatigue syndrome.

PubMed

Hall, K T; Kossowsky, J; Oberlander, T F; Kaptchuk, T J; Saul, J P; Wyller, V B; Fagermoen, E; Sulheim, D; Gjerstad, J; Winger, A; Mukamal, K J

2016-10-01

Clonidine, an α2-adrenergic receptor agonist, decreases circulating norepinephrine and epinephrine, attenuating sympathetic activity. Although catechol-O-methyltransferase (COMT) metabolizes catecholamines, main effectors of sympathetic function, COMT genetic variation effects on clonidine treatment are unknown. Chronic fatigue syndrome (CFS) is hypothesized to result in part from dysregulated sympathetic function. A candidate gene analysis of COMT rs4680 effects on clinical outcomes in the Norwegian Study of Chronic Fatigue Syndrome in Adolescents: Pathophysiology and Intervention Trial (NorCAPITAL), a randomized double-blinded clonidine versus placebo trial, was conducted (N=104). Patients homozygous for rs4680 high-activity allele randomized to clonidine took 2500 fewer steps compared with placebo (Pinteraction=0.04). There were no differences between clonidine and placebo among patients with COMT low-activity alleles. Similar gene-drug interactions were observed for sleep (Pinteraction=0.003) and quality of life (Pinteraction=0.018). Detrimental effects of clonidine in the subset of CFS patients homozygous for COMT high-activity allele warrant investigation of potential clonidine-COMT interaction effects in other conditions.

MB-COMT promoter DNA methylation is associated with working-memory processing in schizophrenia patients and healthy controls

PubMed Central

Walton, Esther; Liu, Jingyu; Hass, Johanna; White, Tonya; Scholz, Markus; Roessner, Veit; Gollub, Randy; Calhoun, Vince D; Ehrlich, Stefan

2014-01-01

Many genetic studies report mixed results both for the associations between COMT polymorphisms and schizophrenia and for the effects of COMT variants on common intermediate phenotypes of the disorder. Reasons for this may include small genetic effect sizes and the modulation of environmental influences. To improve our understanding of the role of COMT in the disease etiology, we investigated the effect of DNA methylation in the MB-COMT promoter on neural activity in the dorsolateral prefrontal cortex during working memory processing as measured by fMRI - an intermediate phenotype for schizophrenia. Imaging and epigenetic data were measured in 102 healthy controls and 82 schizophrenia patients of the Mind Clinical Imaging Consortium (MCIC) study of schizophrenia. Neural activity during the Sternberg Item Recognition Paradigm was acquired with either a 3T Siemens Trio or 1.5T Siemens Sonata and analyzed using the FMRIB Software Library (FSL). DNA methylation measurements were derived from cryo-conserved blood samples. We found a positive association between MB-COMT promoter methylation and neural activity in the left dorsolateral prefrontal cortex in a model using a region-of-interest approach and could confirm this finding in a whole-brain model. This effect was independent of disease status. Analyzing the effect of MB-COMT promoter DNA methylation on a neuroimaging phenotype can provide further evidence for the importance of COMT and epigenetic risk mechanisms in schizophrenia. The latter may represent trans-regulatory or environmental risk factors that can be measured using brain-based intermediate phenotypes. PMID:24837210

Association between COMT, PTSD, and Increased Smoking Following Hurricane Exposure in an Epidemiologic Sample

PubMed Central

Nugent, Nicole R.; Koenen, Karestan C.; Ruggiero, Kenneth J.; Acierno, Ron; Galea, Sandro; Kilpatrick, Dean G.; Gelernter, Joel

2009-01-01

Background Tobacco smoking has been found to increase after the experience of a traumatic event and has been associated with posttraumatic stress disorder (PTSD). Initiation and persistence of cigarette smoking is moderately heritable; two recent investigations have implicated the COMT Val158Met (also known as rs4680) polymorphism in smoking age of initiation, dependence, as well as in quantity and frequency of smoking. Method To examine a possible association of COMT Val158Met and posttrauma increases in cigarette smoking, we studied 614 adults from the 2004 Florida Hurricane Study who returned saliva DNA samples via mail. Results PTSD was strongly associated with increased smoking. Moreover, each COMT Val158Met ‘Met’ allele predicted a 2.10 fold risk of smoking post-hurricane independent of PTSD; follow-up analyses revealed that this finding was primarily driven by European-American males. Conclusions This study represents the first genetic association study (to our knowledge) of smoking behavior following an acute stressor. PMID:20070134

The role of maternal stress during pregnancy, maternal discipline, and child COMT Val158Met genotype in the development of compliance.

PubMed

Kok, Rianne; Bakermans-Kranenburg, Marian J; van Ijzendoorn, Marinus H; Velders, Fleur P; Linting, Mariëlle; Jaddoe, Vincent W V; Hofman, Albert; Verhulst, Frank C; Tiemeier, Henning

2013-07-01

Maternal discipline is an important predictor of child committed compliance. Maternal stress can affect both parenting and child development. In a large population-based cohort study (N = 613) we examined whether maternal discipline mediated the association between maternal stress during pregnancy and child compliance, and whether COMT or DRD4 polymorphisms moderated the association between maternal discipline and child compliance. Family-related and general stress were measured through maternal self-report and genetic material was collected through cord blood sampling at birth. Mother-child dyads were observed at 36 months in disciplinary tasks in which the child was not allowed to touch attractive toys. Maternal discipline and child compliance were observed in two different tasks and independently coded. The association between family stress during pregnancy and child committed compliance was mediated by maternal positive discipline. Children with more COMT Met alleles seemed more susceptible to maternal positive discipline than children with more COMT Val alleles. Copyright © 2012 Wiley Periodicals, Inc.

COMT Val158Met polymorphism moderates the association between PTSD symptom severity and hippocampal volume.

PubMed

Hayes, Jasmeet P; Logue, Mark W; Reagan, Andrew; Salat, David; Wolf, Erika J; Sadeh, Naomi; Spielberg, Jeffrey M; Sperbeck, Emily; Hayes, Scott M; McGlinchey, Regina E; Milberg, William P; Verfaellie, Mieke; Stone, Annjanette; Schichman, Steven A; Miller, Mark W

2017-03-01

Memory-based alterations are among the hallmark symptoms of posttraumatic stress disorder (PTSD) and may be associated with the integrity of the hippocampus. However, neuroimaging studies of hippocampal volume in individuals with PTSD have yielded inconsistent results, raising the possibility that various moderators, such as genetic factors, may influence this association. We examined whether the catechol-O-methyltransferase (COMT) Val158Met polymorphism, which has previously been shown to be associated with hippocampal volume in healthy individuals, moderates the association between PTSD and hippocampal volume. Recent war veterans underwent structural MRI on a 3 T scanner. We extracted volumes of the right and left hippocampus using FreeSurfer and adjusted them for individual differences in intracranial volume. We assessed PTSD severity using the Clinician-Administered PTSD Scale. Hierarchical linear regression was used to model the genotype (Val158Met polymorphism) × PTSD severity interaction and its association with hippocampal volume. We included 146 white, non-Hispanic recent war veterans (90% male, 53% with diagnosed PTSD) in our analyses. A significant genotype × PTSD symptom severity interaction emerged such that individuals with greater current PTSD symptom severity who were homozygous for the Val allele showed significant reductions in left hippocampal volume. The direction of proposed effects is unknown, thus precluding definitive assessment of whether differences in hippocampal volume reflect a consequence of PTSD, a pre-existing characteristic, or both. Our findings suggest that the COMT polymorphism moderates the association between PTSD and hippocampal volume. These results highlight the role that the dopaminergic system has in brain structure and suggest a possible mechanism for memory disturbance in individuals with PTSD.

COMT Val158Met polymorphism moderates the association between PTSD symptom severity and hippocampal volume

PubMed Central

Hayes, Jasmeet P.; Logue, Mark W.; Reagan, Andrew; Salat, David; Wolf, Erika J.; Sadeh, Naomi; Spielberg, Jeffrey M.; Sperbeck, Emily; Hayes, Scott M.; McGlinchey, Regina E.; Milberg, William P.; Verfaellie, Mieke; Stone, Annjanette; Schichman, Steven A.; Miller, Mark W.

2017-01-01

Background Memory-based alterations are among the hallmark symptoms of posttraumatic stress disorder (PTSD) and may be associated with the integrity of the hippocampus. However, neuroimaging studies of hippocampal volume in individuals with PTSD have yielded inconsistent results, raising the possibility that various moderators, such as genetic factors, may influence this association. We examined whether the catechol-O-methyltransferase (COMT) Val158Met polymorphism, which has previously been shown to be associated with hippocampal volume in healthy individuals, moderates the association between PTSD and hippocampal volume. Methods Recent war veterans underwent structural MRI on a 3 T scanner. We extracted volumes of the right and left hippocampus using FreeSurfer and adjusted them for individual differences in intracranial volume. We assessed PTSD severity using the Clinician-Administered PTSD Scale. Hierarchical linear regression was used to model the genotype (Val158Met polymorphism) × PTSD severity interaction and its association with hippocampal volume. Results We included 146 white, non-Hispanic recent war veterans (90% male, 53% with diagnosed PTSD) in our analyses. A significant genotype × PTSD symptom severity interaction emerged such that individuals with greater current PTSD symptom severity who were homozygous for the Val allele showed significant reductions in left hippocampal volume. Limitations The direction of proposed effects is unknown, thus precluding definitive assessment of whether differences in hippocampal volume reflect a consequence of PTSD, a pre-existing characteristic, or both. Conclusion Our findings suggest that the COMT polymorphism moderates the association between PTSD and hippocampal volume. These results highlight the role that the dopaminergic system has in brain structure and suggest a possible mechanism for memory disturbance in individuals with PTSD. PMID:28234210

Gene-gene interactions of CYP2A6 and MAOA polymorphisms on smoking behavior in Chinese male population.

PubMed

Tang, Xun; Guo, Song; Sun, Hongqiang; Song, Xuemei; Jiang, Zuonin; Sheng, Lixiang; Zhou, Dongfeng; Hu, Yonghua; Chen, Dafang

2009-05-01

Nicotine is the major psychoactive ingredient in tobacco, and is responsible for dependence through the nicotine-stimulated reward pathway mediated by the central dopaminergic system. Consequently, genetic polymorphisms in both nicotine metabolism and dopamine catabolism genes may influence smoking behavior, and interact with each other resulting in risk modulation. In this study, we investigated the association and multilocus gene-gene interactions of cytochrome P450 2A6 (CYP2A6), dopamine beta-hydroxylase (DBH), catechol O-methyl transferase (COMT), and monoamine oxidase A (MAOA) polymorphisms with smoking behavior in a community-based Chinese male population. The polymorphisms were genotyped in 203 current smokers, 66 former smokers, and 102 never smokers. Multivariate logistic regression models and the multifactor dimensionality reduction method were used to analyze the association and multilocus gene-gene interactions. Statistically significant trends were shown for increased risk of smoking initiation in participants with CYP2A6*1B/CYP2A6*1B genotypes compared with those with CYP2A6*1A/CYP2A6*1A genotypes [odds ratio (OR)=3.5, 95% confidence interval (CI)= 1.5-8.1], and participants with CYP2A6*1/CYP2A6*1 genotypes were at higher risk of smoking initiation (OR=2.4, 95% CI=1.2-4.5) and smoking persistence (OR=4.0, 95% CI=1.5-10.3) than those who have CYP2A6*4C genotypes. Moreover, the best model involved a gene-gene interaction between MAOA and CYP2A6 was characterized by the multifactor dimensionality reduction method (64.11% accuracy, P<0.001), and indicated that carriers of the combined 1460 T/O genotype for MAOA EcoRV and CYP2A6*1/CYP2A6*1 genotypes were at higher risk of smoking (OR=15.4, 95% CI=4.5-52.5). These findings suggested a substantial influence of CYP2A6 polymorphism as well as the interaction with MAOA resulting in risk modulation on smoking behavior in Chinese male population.

No effect of serotoninergic gene variants on response to interpersonal counseling and antidepressants in major depression.

PubMed

Serretti, Alessandro; Fabbri, Chiara; Pellegrini, Silvia; Porcelli, Stefano; Politi, Pierluigi; Bellino, Silvio; Menchetti, Marco; Mariotti, Veronica; Demi, Cristina; Martinelli, Valentina; Cappucciati, Marco; Bozzatello, Paola; Brignolo, Elena; Brambilla, Paolo; Pae, Chi-Un; Balestrieri, Matteo; De Ronchi, Diana

2013-06-01

Gene variants within the serotonin pathway have been associated with major depressive disorder (MDD) treatment outcomes, however a possible different modulation on pharmacological or psychological treatments has never been investigated. One hundred sixty MDD patients were partially randomized to either inter-personal counseling (IPC) or antidepressants. The primary outcome was remission at week 8. Five serotonergic polymorphisms were investigated (COMT rs4680, HTR1A rs6295, HTR2A rs2224721, HTR2A rs7997012 and SLC6A4 rs421417). IPC (n=43) and antidepressant (n=117) treated patients did not show any difference in remission rates at week 8 (corrected for baseline severity, age and center). None of the studied gene variants impacted on response and remission rates at week 8 neither in the IPC nor in the antidepressant group. An analysis of the whole sample showed a trend of association between rs7997012 AA genotype and a better treatment outcome. Our study confirms that IPC is an effective psychological intervention comparable to antidepressants in mild-moderate MDD. Polymorphisms related to the serotonin system did not exert a major effect on clinical outcomes in none of the treatment groups.

Perceived Stress in Adults Aged 65 to 90: Relations to Facets of Time Perspective and COMT Val158Met Polymorphism.

PubMed

Rönnlund, Michael; Åström, Elisabeth; Adolfsson, Rolf; Carelli, Maria G

2018-01-01

This study examined the relation between perceived stress and time perspective (views of past, present, future) in a population-based sample of older adults (65-90 years, N = 340). The Perceived Questionnaire (PSQ index) was used to measure stress and the Swedish version of the Zimbardo Time Perspective Inventory (S-ZTPI) was used to operationalize time perspective. Unlike the original inventory, S-ZTPI separates positive and negative aspects of a future time perspective and we hypothesized that the Future Negative (FN) scale would be important to account for variations in stress. Additionally, associations with Catechol-O-methyltransferase ( COMT ) Val 158 Met polymorphism were examined, motivated by prior associations of this single nucleotide polymorphism (SNP) with stress (or "anxiety") related personality traits. In line with the hypotheses, FN was the strongest predictor of PSQ index scores in multiple regression analyses. In a related vein, the dichotomization of the unitary Future scale increased the association between PSQ scores and a measure of deviations from a balanced time perspective, i.e., the difference between a proposed optimal and observed ZTPI profile. Finally, higher levels of stress as well as higher scores on FN were observed in COMT Val/Val carriers, at least among men. This suggests a shared dopaminergic genetic influence on these variables. Collectively, the results demonstrate that perceived stress is closely linked to time perspective and highlight the need to take negative aspects of a future temporal orientation into account to understand this relation.

Cathecol-O-methyl transferase Val158Met genotype is not a risk factor for conversion disorder.

PubMed

Armagan, E; Almacıoglu, M L; Yakut, T; Köse, A; Karkucak, M; Köksal, O; Görükmez, O

2013-03-19

Alterations in catechol-O-methyltransferase (COMT) activity are involved in various types of neurological disorders. We examined a possible association between the COMT Val158Met polymorphism and conversion disorder in a study of 48 patients with conversion disorder and 48 control patients. In the conversion disorder group, 31 patients were Val/Met heterozygotes, 15 patients were Val/Val homozygotes and 2 patients were Met/Met homozygotes. In the control group, 32 patients were Val/Met heterozygotes and 16 patients were Val/Val homozygotes. There was no significant difference between the groups. We conclude that the COMT Val158Met genotype is quite common in Turkey and that it is not a risk factor for conversion disorder in the Turkish population.

The role of catechol-O-methyltransferase in catechol-enhanced erythroid differentiation of K562 cells.

PubMed

Suriguga; Li, Xiao-Fei; Li, Yang; Yu, Chun-Hong; Li, Yi-Ran; Yi, Zong-Chun

2013-12-15

Catechol is widely used in pharmaceutical and chemical industries. Catechol is also one of phenolic metabolites of benzene in vivo. Our previous study showed that catechol improved erythroid differentiation potency of K562 cells, which was associated with decreased DNA methylation in erythroid specific genes. Catechol is a substrate for the catechol-O-methyltransferase (COMT)-mediated methylation. In the present study, the role of COMT in catechol-enhanced erythroid differentiation of K562 cells was investigated. Benzidine staining showed that exposure to catechol enhanced hemin-induced hemoglobin accumulation and induced mRNA expression of erythroid specific genes in K562 cells. Treatment with catechol caused a time- and concentration-dependent increase in guaiacol concentration in the medium of cultured K562 cells. When COMT expression was knocked down by COMT shRNA expression in K562 cells, the production of guaiacol significantly reduced, and the sensitivity of K562 cells to cytotoxicity of catechol significantly increased. Knockdown of COMT expression by COMT shRNA expression also eliminated catechol-enhanced erythroid differentiation of K562 cells. In addition, the pre-treatment with methyl donor S-adenosyl-L-methionine or its demethylated product S-adenosyl-L-homocysteine induced a significant increase in hemin-induced Hb synthesis in K562 cells and the mRNA expression of erythroid specific genes. These findings indicated that O-methylation catalyzed by COMT acted as detoxication of catechol and involved in catechol-enhanced erythroid differentiation of K562 cells, and the production of S-adenosyl-L-homocysteine partly explained catechol-enhanced erythroid differentiation. © 2013.

Obesity is associated with genetic variants that alter dopamine availability.

PubMed

Need, A C; Ahmadi, K R; Spector, T D; Goldstein, D B

2006-05-01

Human and animal studies have implicated dopamine in appetite regulation, and family studies have shown that BMI has a strong genetic component. Dopamine availability is controlled largely by three enzymes: COMT, MAOA and MAOB, and by the dopamine transporter SLC6A3, and each gene has a well-characterized functional variant. Here we look at these four functional polymorphisms together, to investigate how heritable variation in dopamine levels influences the risk of obesity in a cohort of 1150, including 240 defined as obese (BMI > or = 30). The COMT and SLC6A3 polymorphisms showed no association with either weight, BMI or obesity risk. We found, however, that both MAOA and MAOB show an excess of the low-activity genotypes in obese individuals (MAOA:chi2= 15.45, p = 0.004; MAOB:chi2= 8.05, p = 0.018). Additionally, the MAOA genotype was significantly associated with both weight (p = 0.0005) and BMI (p = 0.001). When considered together, the 'at risk genotype'--low activity genotypes at both the MAOA and MAOB loci--shows a relative risk for obesity of 5.01. These results have not been replicated and, given the experience of complex trait genetics, warrant caution in interpretation. In implicating both the MAOA and MOAB variants, however, this study provides the first indication that dopamine availability (as opposed to other effects of MAOA) is involved in human obesity. It is therefore a priority to assess the associations in replication datasets.

Orientation and cellular distribution of membrane-bound catechol-O-methyltransferase in cortical neurons: implications for drug development.

PubMed

Chen, Jingshan; Song, Jian; Yuan, Peixiong; Tian, Qingjun; Ji, Yuanyuan; Ren-Patterson, Renee; Liu, Guangping; Sei, Yoshitasu; Weinberger, Daniel R

2011-10-07

Catechol-O-methyltransferase (COMT) is a key enzyme for inactivation and metabolism of catechols, including dopamine, norepinephrine, caffeine, and estrogens. It plays an important role in cognition, arousal, pain sensitivity, and stress reactivity in humans and in animal models. The human COMT gene is associated with a diverse spectrum of human behaviors and diseases from cognition and psychiatric disorders to chronic pain and cancer. There are two major forms of COMT proteins, membrane-bound (MB) COMT and soluble (S) COMT. MB-COMT is the main form in the brain. The cellular distribution of MB-COMT in cortical neurons remains unclear and the orientation of MB-COMT on the cellular membrane is controversial. In this study, we demonstrate that MB-COMT is located in the cell body and in axons and dendrites of rat cortical neurons. Analyses of MB-COMT orientation with computer simulation, flow cytometry and a cell surface enzyme assay reveal that the C-terminal catalytic domain of MB-COMT is in the extracellular space, which suggests that MB-COMT can inactivate synaptic and extrasynaptic dopamine on the surface of presynaptic and postsynaptic neurons. Finally, we show that the COMT inhibitor tolcapone induces cell death via the mechanism of apoptosis, and its cytotoxicity is dependent on dosage and correlated with COMT Val/Met genotypes in human lymphoblastoid cells. These results suggest that MB-COMT specific inhibitors can be developed and that tolcapone may be less hazardous at low doses and in specific genetic backgrounds.

The Role of Dopamine in Anticipatory Pursuit Eye Movements: Insights from Genetic Polymorphisms in Healthy Adults

PubMed Central

Hennig, Jürgen

2016-01-01

Abstract There is a long history of eye movement research in patients with psychiatric diseases for which dysfunctions of neurotransmission are considered to be the major pathologic mechanism. However, neuromodulation of oculomotor control is still hardly understood. We aimed to investigate in particular the impact of dopamine on smooth pursuit eye movements. Systematic variability in dopaminergic transmission due to genetic polymorphisms in healthy subjects offers a noninvasive opportunity to determine functional associations. We measured smooth pursuit in 110 healthy subjects genotyped for two well-documented polymorphisms, the COMT Val158Met polymorphism and the SLC6A3 3′-UTR-VNTR polymorphism. Pursuit paradigms were chosen to particularly assess the ability of the pursuit system to initiate tracking when target motion onset is blanked, reflecting the impact of extraretinal signals. In contrast, when following a fully visible target sensory, retinal signals are available. Our results highlight the crucial functional role of dopamine for anticipatory, but not for sensory-driven, pursuit processes. We found the COMT Val158Met polymorphism specifically associated with anticipatory pursuit parameters, emphasizing the dominant impact of prefrontal dopamine activity on complex oculomotor control. In contrast, modulation of striatal dopamine activity by the SLC6A3 3′-UTR-VNTR polymorphism had no significant functional effect. Though often neglected so far, individual differences in healthy subjects provide a promising approach to uncovering functional mechanisms and can be used as a bridge to understanding deficits in patients. PMID:28101524

The Role of Dopamine in Anticipatory Pursuit Eye Movements: Insights from Genetic Polymorphisms in Healthy Adults.

PubMed

Billino, Jutta; Hennig, Jürgen; Gegenfurtner, Karl R

2016-01-01

There is a long history of eye movement research in patients with psychiatric diseases for which dysfunctions of neurotransmission are considered to be the major pathologic mechanism. However, neuromodulation of oculomotor control is still hardly understood. We aimed to investigate in particular the impact of dopamine on smooth pursuit eye movements. Systematic variability in dopaminergic transmission due to genetic polymorphisms in healthy subjects offers a noninvasive opportunity to determine functional associations. We measured smooth pursuit in 110 healthy subjects genotyped for two well-documented polymorphisms, the COMT Val 158 Met polymorphism and the SLC6A3 3'-UTR-VNTR polymorphism. Pursuit paradigms were chosen to particularly assess the ability of the pursuit system to initiate tracking when target motion onset is blanked, reflecting the impact of extraretinal signals. In contrast, when following a fully visible target sensory, retinal signals are available. Our results highlight the crucial functional role of dopamine for anticipatory, but not for sensory-driven, pursuit processes. We found the COMT Val 158 Met polymorphism specifically associated with anticipatory pursuit parameters, emphasizing the dominant impact of prefrontal dopamine activity on complex oculomotor control. In contrast, modulation of striatal dopamine activity by the SLC6A3 3'-UTR-VNTR polymorphism had no significant functional effect. Though often neglected so far, individual differences in healthy subjects provide a promising approach to uncovering functional mechanisms and can be used as a bridge to understanding deficits in patients.

An experimental study of catechol-o-methyltransferase Val158Met moderation of delta-9-tetrahydrocannabinol-induced effects on psychosis and cognition.

PubMed

Henquet, Cécile; Rosa, Araceli; Krabbendam, Lydia; Papiol, Sergi; Fananás, Lourdes; Drukker, Marjan; Ramaekers, Johannes G; van Os, Jim

2006-12-01

Observational studies have suggested that psychometric psychosis liability and a functional polymorphism in the catechol-O-methyltransferase (COMT Val(158)Met) gene moderate the psychosis-inducing effect of cannabis. To replicate and extend this finding, a double-blind, placebo-controlled cross-over design was used in which patients with a psychotic disorder (n=30), relatives of patients with a psychotic disorder (n=12), and healthy controls (n=32) were exposed to Delta-9-tetrahydrocannabinol (Delta-9-THC, the principal component of cannabis) or placebo, followed by cognitive assessment and assessment of current psychotic experiences. Previous expression of psychometric psychosis liability was also assessed. Models of current psychotic experiences and cognition were examined with multilevel random regression analyses to assess (i) main effects of genotype and condition, (ii) interactions between condition and genotype, and (iii) three-way interactions between condition, genotype, and psychometric psychosis liability. Carriers of the Val allele were most sensitive to Delta-9-THC-induced psychotic experiences, but this was conditional on prior evidence of psychometric psychosis liability. Delta-9-THC impacted negatively on cognitive measures. Carriers of the Val allele were also more sensitive to Delta-9-THC-induced memory and attention impairments compared to carriers of the Met allele. Experimental effects of Delta-9-THC on cognition and psychosis are moderated by COMT Val(158)Met genotype, but the effects may in part be conditional on the additional presence of pre-existing psychosis liability. The association between cannabis and psychosis may represent higher order gene-environment and gene-gene interactions.

Evidence that COMT genotype and proline interact on negative-symptom outcomes in schizophrenia and bipolar disorder.

PubMed

Clelland, C L; Drouet, V; Rilett, K C; Smeed, J A; Nadrich, R H; Rajparia, A; Read, L L; Clelland, J D

2016-09-13

Elevated peripheral proline is associated with psychiatric disorders, and there is evidence that proline is a neuromodulator. The proline dehydrogenase (PRODH) gene, which encodes the enzyme that catalyzes proline catabolism, maps to human chromosome 22q11.2, a region conferring risk of schizophrenia. In the Prodh-null mouse, an interaction between elevated peripheral proline and another 22q11.2 gene, catechol-O-methyltransferase (COMT), on neurotransmission and behavior has been reported. We explored the relationship between fasting plasma proline levels and COMT Val(158)Met genotype on symptoms (positive, negative and total) in schizophrenia patients. In an exploratory study we also examined symptom change in patients with bipolar disorder. There was a significant interaction between peripheral proline and COMT on negative symptoms in schizophrenia (P<0.0001, n=95). In COMT Val/Val patients, high proline was associated with low Scale for the Assessment of Negative Symptom (SANS) scores. In contrast, high proline was associated with high SANS scores in patients carrying a Met allele. The relationship between proline and COMT also appears to modify negative symptoms across psychiatric illness. In bipolar disorder, a significant interaction was also observed on negative-symptom change (P=0.007, n=43). Negative symptoms are intractable and largely unaddressed by current medications. These data indicate a significant interaction between peripheral proline and COMT genotype, influencing negative symptoms in schizophrenia and bipolar disorder. That high proline has converse effects on symptoms by COMT genotype, may have implications for therapeutic decisions.

Facial emotion recognition in schizophrenia: An exploratory study on the role of comorbid alcohol and substance use disorders and COMT Val158Met.

PubMed

Carrà, Giuseppe; Nicolini, Gabriella; Lax, Annamaria; Bartoli, Francesco; Castellano, Filippo; Chiorazzi, Alessia; Gamba, Giulia; Bava, Mattia; Crocamo, Cristina; Papagno, Costanza

2017-11-01

To explore whether facial emotion recognition (FER), impaired in both schizophrenia and alcohol and substance use disorders (AUDs/SUDs), is additionally compromised among comorbid subjects, also considering the role of catechol-O-methyltransferase (COMT) Val158Met. We conducted a cross-sectional study, randomly recruiting 67 subjects with a DSM-IV-TR diagnosis of schizophrenia, and rigorously assessing AUDs/SUDs and COMT Val158Met polymorphism. FER was assessed using the Ekman 60 Faces Test- EK-60F. As a whole, the sample scored significantly lower than normative data on EK-60F. However, subjects with comorbid AUDs/SUDs did not perform worse on EK-60F than those without, who had a better performance on EK-60F if they carried the COMT Val/Met variant. This study is the first to date examining the impact of AUDs/SUDs and COMT variants on FER in an epidemiologically representative sample of subjects with schizophrenia. Our findings do not suggest an additional impairment from comorbid AUDs/SUDs on FER among subjects with schizophrenia, whilst COMT Val158Met, though based on a limited sample, might have a role just among those without AUDs/SUDs. Based on our results, additional research is needed also exploring differential roles of various substances. Copyright © 2017 John Wiley & Sons, Ltd.

Catechol-O-Methyltransferase moderates effect of stress mindset on affect and cognition

PubMed Central

Akinola, Modupe; Turnwald, Bradley P.; Kaptchuk, Ted J.; Hall, Kathryn T.

2018-01-01

There is evidence that altering stress mindset—the belief that stress is enhancing vs. debilitating—can change cognitive, affective and physiological responses to stress. However individual differences in responsiveness to stress mindset manipulations have not been explored. Given the previously established role of catecholamines in both placebo effects and stress, we hypothesized that genetic variation in catechol-O-methyltransferase (COMT), an enzyme that metabolizes catecholamines, would moderate responses to an intervention intended to alter participants’ mindsets about stress. Participants (N = 107) were exposed to a stress mindset manipulation (videos highlighting either the enhancing or debilitating effects of stress) prior to engaging in a Trier Social Stress task and subsequent cognitive tasks. The associations of the COMT rs4680 polymorphism with the effect of stress mindset video manipulations on cognitive and affective responses were examined. Genetic variation at rs4680 modified the effects of stress mindset on affective and cognitive responses to stress. Individuals homozygous for rs4680 low-activity allele (met/met) were responsive to the stress-is-enhancing mindset manipulation as indicated by greater increases in positive affect, improved cognitive functioning, and happiness bias in response to stress. Conversely, individuals homozygous for the high-activity allele (val/val) were not as responsive to the stress mindset manipulation. These results suggest that responses to stress mindset intervention may vary with COMT genotype. These findings contribute to the understanding of gene by environment interactions for mindset interventions and stress reactivity and therefore warrant further investigations. PMID:29677196

Catechol-O-methyltransferase (COMT) influences the connectivity of the prefrontal cortex at rest

PubMed Central

Tunbridge, Elizabeth M.; Farrell, Sarah M.; Harrison, Paul J.; Mackay, Clare E.

2013-01-01

Catechol-O-methyltransferase (COMT) modulates dopamine in the prefrontal cortex (PFC) and influences PFC dopamine-dependent cognitive task performance. A human COMT polymorphism (Val158Met) alters enzyme activity and is associated with both the activation and functional connectivity of the PFC during task performance, particularly working memory. Here, we used functional magnetic resonance imaging and a data-driven, independent components analysis (ICA) approach to compare resting state functional connectivity within the executive control network (ECN) between young, male COMT Val158 (n = 27) and Met158 (n = 28) homozygotes. COMT genotype effects on grey matter were assessed using voxel-based morphometry. COMT genotype significantly modulated functional connectivity within the ECN, which included the head of the caudate, and anterior cingulate and frontal cortical regions. Val158 homozygotes showed greater functional connectivity between a cluster within the left ventrolateral PFC and the rest of the ECN (using a threshold of Z > 2.3 and a family-wise error cluster significance level of p < 0.05). This difference occurred in the absence of any alterations in grey matter. Our data show that COMT Val158Met affects the functional connectivity of the PFC at rest, complementing its prominent role in the activation and functional connectivity of this region during cognitive task performance. The results suggest that genotype-related differences in prefrontal dopaminergic tone result in neuroadaptive changes in basal functional connectivity, potentially including subtle COMT genotype-dependent differences in the relative coupling of task-positive and task-negative regions, which could in turn contribute to its effects on brain activation, connectivity, and behaviour. PMID:23228511

[Effects of anxiety and the COMT gene on cortical evoked potentials and performance effectiveness of selective attention].

PubMed

Alfimova, M V; Golimbet, V E; Lebedeva, I S; Korovaĭtseva, G I; Lezheĭko, T V

2014-01-01

We studied influence of the anxiety-related trait Harm Avoidance and the COMT gene, which is an important modulator of prefrontal functioning, on event-related potentials in oddball paradigm and performance effectiveness of selective attention. For 50 individuals accuracy and time of searching words among letters at any desired rate and then under an instruction to perform the task as quickly and accurate as possible were measured. Scores on the Harm Avoidance scale from Cloninger's Temperament and Character Inventory, N100 and P300 parameters, and COMTVa1158Met genotypes were obtained for them as well. Searching accuracy and time were mainly related to N100 amplitude. The COMT genotype and Harm Avoidance did not affect N100 amplitude; however, the N100 amplitude modulated their effects on accuracy and time dynamics. Harm Avoidance was positively correlated with P300 latency. The results suggest that anxiety and the COMT gene effects on performance effectiveness of selective attention depend on cognitive processes reflected in N100 parameters.

Catechol-O-methyltransferase (COMT) genotype affects cognitive control during total sleep deprivation.

PubMed

Satterfield, Brieann C; Hinson, John M; Whitney, Paul; Schmidt, Michelle A; Wisor, Jonathan P; Van Dongen, Hans P A

2018-02-01

Adaptive decision making is profoundly impaired by total sleep deprivation (TSD). This suggests that TSD impacts fronto-striatal pathways involved in cognitive control, where dopamine is a key neuromodulator. In the prefrontal cortex (PFC), dopamine is catabolized by the enzyme catechol-O-methyltransferase (COMT). A functional polymorphism (Val158Met) influences COMT's enzymatic activity, resulting in markedly different levels of prefrontal dopamine. We investigated the effect of this polymorphism on adaptive decision making during TSD. Sixty-six healthy young adults participated in one of two in-laboratory studies. After a baseline day, subjects were randomized to either a TSD group (n = 32) with 38 h or 62 h of extended wakefulness or a well-rested control group (n = 34) with 10 h nighttime sleep opportunities. Subjects performed a go/no-go reversal learning (GNGr) task at well-rested baseline and again during TSD or equivalent control. During the task, subjects were required to learn stimulus-response relationships from accuracy feedback. The stimulus-response relationships were reversed halfway through the task, which required subjects to learn the new stimulus-response relationships from accuracy feedback. Performance on the GNGr task was quantified by discriminability (d') between go and no-go stimuli before and after the stimulus-response reversal. GNGr performance did not differ between COMT genotypes when subjects were well-rested. However, TSD exposed a significant vulnerability to adaptive decision making impairment in subjects with the Val allele. Our results indicate that sleep deprivation degrades cognitive control through a fronto-striatal, dopaminergic mechanism. Copyright © 2017 Elsevier Ltd. All rights reserved.

COMT genotype, gambling activity, and cognition.

PubMed

Grant, Jon E; Leppink, Eric W; Redden, Sarah A; Odlaug, Brian L; Chamberlain, Samuel R

2015-09-01

Neuropsychological studies of adults with problem gambling indicate impairments across multiple cognitive domains. Catechol-O-methyltransferase (COMT) plays a unique role in the regulation of dopamine in the prefrontal cortex, and has been implicated in the cognitive dysfunction evident in problem gambling. This study examined adults with varying levels of gambling behavior to determine whether COMT genotype was associated with differences in gambling symptoms and cognitive functioning. 260 non-treatment-seeking adults aged 18-29 years with varying degrees of gambling behavior provided saliva samples for genotyping COMT val158met (rs4680). All subjects underwent clinical evaluations and neurocognitive assessment of decision-making, working memory, and impulsivity. The Val/Val COMT genotype was associated with the largest percentage of subjects with gambling disorder (31.8%), a rate significantly different from the Val/Met (13.2%) group (p = 0.001). The Val/Val COMT group was also associated with significantly more gambling disorder diagnostic criteria being met, greater frequency of gambling behavior, and significantly worse cognitive performance on the Cambridge Gamble Task (risk adjustment and delay aversion) and the Spatial Working Memory task (total errors). This study adds to the growing literature on the role of COMT in impulsive behaviors by showing that the Val/Val genotype was associated with specific clinical and cognitive elements among young adults who gamble, in the absence of differences on demographic measures and other cognitive domains. Future work should consider using genotyping to explore whether certain polymorphisms predict subsequent development of impulsive behaviors including gambling disorder, and treatment outcomes. Copyright © 2015 Elsevier Ltd. All rights reserved.

Genetic determinants of time perception mediated by the serotonergic system.

PubMed

Sysoeva, Olga V; Tonevitsky, Alexander G; Wackermann, Jirí

2010-09-17

The present study investigates neurobiological underpinnings of individual differences in time perception. Forty-four right-handed Russian Caucasian males (18-35 years old) participated in the experiment. The polymorphism of the genes related to the activity of serotonin (5-HT) and dopamine (DA)-systems (such as 5-HTT, 5HT2a, MAOA, DAT, DRD2, COMT) was determined upon the basis of DNA analysis according to a standard procedure. Time perception in the supra-second range (mean duration 4.8 s) was studied, using the duration discrimination task and parametric fitting of psychometric functions, resulting in individual determination of the point of subjective equality (PSE). Assuming the 'dual klepsydra model' of internal duration representation, the PSE values were transformed into equivalent values of the parameter κ (kappa), which is a measure of the 'loss rate' of the duration representation. An association between time representation parameters (PSE and κ, respectively) and 5-HT-related genes was found, but not with DA-related genes. Higher 'loss rate' (κ) of the cumulative duration representation were found for the carriers of genotypes characterized by higher 5-HT transmission, i.e., 1) lower 5-HT reuptake, known for the 5-HTTLPR SS polymorphism compared with LL, 2) lower 5-HT degradation, described for the 'low expression' variant of MAOA VNTR gene compared with 'high expression' variant, and 3) higher 5-HT2a receptor density, proposed for the TT polymorphism of 5-HT2a T102C gene compared with CC. Convergent findings of the present study and previous psychopharmacological studies suggest an action path from 5-HT-activity-related genes, via activity of 5-HT in the brain, to time perception. An involvement of the DA-system in the encoding of durations in the supra-second range is questioned.

Review of Opioid Pharmacogenetics and Considerations for Pain Management.

PubMed

Owusu Obeng, Aniwaa; Hamadeh, Issam; Smith, Michael

2017-09-01

Opioid analgesics are the standards of care for the treatment of moderate to severe nociceptive pain, particularly in the setting of cancer and surgery. Their analgesic properties mainly emanate from stimulation of the μ receptors, which are encoded by the OPRM1 gene. Hepatic metabolism represents the major route of elimination, which, for some opioids, namely codeine and tramadol, is necessary for their bioactivation into more potent analgesics. The highly polymorphic nature of the genes coding for phase I and phase II enzymes (pharmacokinetics genes) that are involved in the metabolism and bioactivation of opioids suggests a potential interindividual variation in their disposition and, most likely, response. In fact, such an association has been substantiated in several pharmacokinetic studies described in this review, in which drug exposure and/or metabolism differed significantly based on the presence of polymorphisms in these pharmacokinetics genes. Furthermore, in some studies, the observed variability in drug exposure translated into differences in the incidence of opioid-related adverse effects, particularly nausea, vomiting, constipation, and respiratory depression. Although the influence of polymorphisms in pharmacokinetics genes, as well as pharmacodynamics genes (OPRM1 and COMT) on response to opioids has been a subject of intense research, the results have been somehow conflicting, with some evidence insinuating for a potential role for OPRM1. The Clinical Pharmacogenetics Implementation Consortium guidelines provide CYP2D6-guided therapeutic recommendations to individualize treatment with tramadol and codeine. However, implementation guidelines for other opioids, which are more commonly used in real-world settings for pain management, are currently lacking. Hence, further studies are warranted to bridge this gap in our knowledge base and ultimately ascertain the role of pharmacogenetic markers as predictors of response to opioid analgesics. © 2017 Pharmacotherapy Publications, Inc.

Working memory brain activity and capacity link MAOA polymorphism to aggressive behavior during development.

PubMed

Ziermans, T; Dumontheil, I; Roggeman, C; Peyrard-Janvid, M; Matsson, H; Kere, J; Klingberg, T

2012-02-28

A developmental increase in working memory capacity is an important part of cognitive development, and low working memory (WM) capacity is a risk factor for developing psychopathology. Brain activity represents a promising endophenotype for linking genes to behavior and for improving our understanding of the neurobiology of WM development. We investigated gene-brain-behavior relationships by focusing on 18 single-nucleotide polymorphisms (SNPs) located in six dopaminergic candidate genes (COMT, SLC6A3/DAT1, DBH, DRD4, DRD5, MAOA). Visuospatial WM (VSWM) brain activity, measured with functional magnetic resonance imaging, and VSWM capacity were assessed in a longitudinal study of typically developing children and adolescents. Behavioral problems were evaluated using the Child Behavior Checklist (CBCL). One SNP (rs6609257), located ~6.6 kb downstream of the monoamine oxidase A gene (MAOA) on human chromosome X, significantly affected brain activity in a network of frontal, parietal and occipital regions. Increased activity in this network, but not in caudate nucleus or anterior prefrontal regions, was correlated with VSWM capacity, which in turn predicted externalizing (aggressive/oppositional) symptoms, with higher WM capacity associated with fewer externalizing symptoms. There were no direct significant correlations between rs6609257 and behavioral symptoms. These results suggest a mediating role of WM brain activity and capacity in linking the MAOA gene to aggressive behavior during development.

Perceived Stress in Adults Aged 65 to 90: Relations to Facets of Time Perspective and COMT Val158Met Polymorphism

PubMed Central

Rönnlund, Michael; Åström, Elisabeth; Adolfsson, Rolf; Carelli, Maria G.

2018-01-01

This study examined the relation between perceived stress and time perspective (views of past, present, future) in a population-based sample of older adults (65–90 years, N = 340). The Perceived Questionnaire (PSQ index) was used to measure stress and the Swedish version of the Zimbardo Time Perspective Inventory (S-ZTPI) was used to operationalize time perspective. Unlike the original inventory, S-ZTPI separates positive and negative aspects of a future time perspective and we hypothesized that the Future Negative (FN) scale would be important to account for variations in stress. Additionally, associations with Catechol-O-methyltransferase (COMT) Val158Met polymorphism were examined, motivated by prior associations of this single nucleotide polymorphism (SNP) with stress (or “anxiety”) related personality traits. In line with the hypotheses, FN was the strongest predictor of PSQ index scores in multiple regression analyses. In a related vein, the dichotomization of the unitary Future scale increased the association between PSQ scores and a measure of deviations from a balanced time perspective, i.e., the difference between a proposed optimal and observed ZTPI profile. Finally, higher levels of stress as well as higher scores on FN were observed in COMT Val/Val carriers, at least among men. This suggests a shared dopaminergic genetic influence on these variables. Collectively, the results demonstrate that perceived stress is closely linked to time perspective and highlight the need to take negative aspects of a future temporal orientation into account to understand this relation. PMID:29623060

COMT Val[superscript 108/158] Met Gene Variant, Birth Weight, and Conduct Disorder in Children with ADHD

ERIC Educational Resources Information Center

Sengupta, Sarojini M.; Grizenko, Natalie; Schmitz, Norbert; Schwartz, George; Amor, Leila Ben; Bellingham, Johanne; de Guzman, Rosherrie; Polotskaia, Anna; Stepanian, Marina Ter; Thakur, Geeta; Joober, Ridha

2006-01-01

Objective: In a recent study, Thapar and colleagues reported that COMT "gene variant and birth weight predict early-onset antisocial behavior in children" with attention-deficit/hyperactivity disorder. We have attempted to replicate these findings in a group of ADHD children using a similar research design. Method: Children (n = 191)…

Financial and Psychological Risk Attitudes Associated with Two Single Nucleotide Polymorphisms in the Nicotine Receptor (CHRNA4) Gene

PubMed Central

Roe, Brian E.; Tilley, Michael R.; Gu, Howard H.; Beversdorf, David Q.; Sadee, Wolfgang; Haab, Timothy C.; Papp, Audrey C.

2009-01-01

With recent advances in understanding of the neuroscience of risk taking, attention is now turning to genetic factors that may contribute to individual heterogeneity in risk attitudes. In this paper we test for genetic associations with risk attitude measures derived from both the psychology and economics literature. To develop a long-term prospective study, we first evaluate both types of risk attitudes and find that the economic and psychological measures are poorly correlated, suggesting that different genetic factors may underlie human response to risk faced in different behavioral domains. We then examine polymorphisms in a spectrum of candidate genes that affect neurotransmitter systems influencing dopamine regulation or are thought to be associated with risk attitudes or impulsive disorders. Analysis of the genotyping data identified two single nucleotide polymorphisms (SNPs) in the gene encoding the alpha 4 nicotine receptor (CHRNA4, rs4603829 and rs4522666) that are significantly associated with harm avoidance, a risk attitude measurement drawn from the psychology literature. Novelty seeking, another risk attitude measure from the psychology literature, is associated with several COMT (catechol-O-methyl transferase) SNPs while economic risk attitude measures are associated with several VMAT2 (vesicular monoamine transporter) SNPs, but the significance of these associations did not withstand statistical adjustment for multiple testing and requires larger cohorts. These exploratory results provide a starting point for understanding the genetic basis of risk attitudes by considering the range of methods available for measuring risk attitudes and by searching beyond the traditional direct focus on dopamine and serotonin receptor and transporter genes. PMID:19693267

The catechol-O-methyltransferase (COMT) Val158Met genotype modulates working memory-related dorsolateral prefrontal response and performance in bipolar disorder.

PubMed

Miskowiak, K W; Kjaerstad, H L; Støttrup, M M; Svendsen, A M; Demant, K M; Hoeffding, L K; Werge, T M; Burdick, K E; Domschke, K; Carvalho, A F; Vieta, E; Vinberg, M; Kessing, L V; Siebner, H R; Macoveanu, J

2017-05-01

Cognitive dysfunction affects a substantial proportion of patients with bipolar disorder (BD), and genetic-imaging paradigms may aid in the elucidation of mechanisms implicated in this symptomatic domain. The Val allele of the functional Val158Met polymorphism of the catechol-O-methyltransferase (COMT) gene is associated with reduced prefrontal cortex dopamine and exaggerated working memory-related prefrontal activity. This functional magnetic resonance imaging (fMRI) study investigated for the first time whether the COMT Val158Met genotype modulates prefrontal activity during spatial working memory in BD. Sixty-four outpatients with BD in full or partial remission were stratified according to COMT Val158Met genotype (ValVal [n=13], ValMet [n=34], and MetMet [n=17]). The patients completed a spatial n-back working memory task during fMRI and the Cambridge Neuropsychological Test Automated Battery (CANTAB) Spatial Working Memory test outside the scanner. During high working memory load (2-back vs 1-back), Val homozygotes displayed decreased activity relative to ValMet individuals, with Met homozygotes displaying intermediate levels of activity in the right dorsolateral prefrontal cortex (dlPFC) (P=.016). Exploratory whole-brain analysis revealed a bilateral decrease in working memory-related dlPFC activity in the ValVal group vs the ValMet group which was not associated with differences in working memory performance during fMRI. Outside the MRI scanner, Val carriers performed worse in the CANTAB Spatial Working Memory task than Met homozygotes (P≤.006), with deficits being most pronounced in Val homozygotes. The association between Val allelic load, dlPFC activity and WM impairment points to a putative role of aberrant PFC dopamine tonus in the cognitive impairments in BD. © 2017 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Genetic and Non-genetic Factors Associated With Constipation in Cancer Patients Receiving Opioids

PubMed Central

Laugsand, Eivor A; Skorpen, Frank; Kaasa, Stein; Sabatowski, Rainer; Strasser, Florian; Fayers, Peter; Klepstad, Pål

2015-01-01

Objectives: To examine whether the inter-individual variation in constipation among patients receiving opioids for cancer pain is associated with genetic or non-genetic factors. Methods: Cancer patients receiving opioids were included from 17 centers in 11 European countries. Intensity of constipation was reported by 1,568 patients on a four-point categorical scale. Non-genetic factors were included as covariates in stratified regression analyses on the association between constipation and 75 single-nucleotide polymorphisms (SNPs) within 15 candidate genes related to opioid- or constipation-signaling pathways (HTR3E, HTR4, HTR2A, TPH1, ADRA2A, CHRM3, TACR1, CCKAR, KIT, ARRB2, GHRL, ABCB1, COMT, OPRM1, and OPRD1). Results: The non-genetic factors significantly associated with constipation were type of laxative, mobility and place of care among patients receiving laxatives (N=806), in addition to Karnofsky performance status and presence of metastases among patients not receiving laxatives (N=762) (P<0.01). Age, gender, body mass index, cancer diagnosis, time on opioids, opioid dose, and type of opioid did not contribute to the inter-individual differences in constipation. Five SNPs, rs1800532 in TPH1, rs1799971 in OPRM1, rs4437575 in ABCB1, rs10802789 in CHRM3, and rs2020917 in COMT were associated with constipation (P<0.01). Only rs2020917 in COMT passed the Benjamini–Hochberg criterion for a 10% false discovery rate. Conclusions: Type of laxative, mobility, hospitalization, Karnofsky performance status, presence of metastases, and five SNPs within TPH1, OPRM1, ABCB1, CHRM3, and COMT may contribute to the variability in constipation among cancer patients treated with opioids. Knowledge of these factors may help to develop new therapies and to identify patients needing a more individualized approach to treatment. PMID:26087058

No Effect of Serotoninergic Gene Variants on Response to Interpersonal Counseling and Antidepressants in Major Depression

PubMed Central

Fabbri, Chiara; Pellegrini, Silvia; Porcelli, Stefano; Politi, Pierluigi; Bellino, Silvio; Menchetti, Marco; Mariotti, Veronica; Demi, Cristina; Martinelli, Valentina; Cappucciati, Marco; Bozzatello, Paola; Brignolo, Elena; Brambilla, Paolo; Pae, Chi-Un; Balestrieri, Matteo; De Ronchi, Diana

2013-01-01

Objective Gene variants within the serotonin pathway have been associated with major depressive disorder (MDD) treatment outcomes, however a possible different modulation on pharmacological or psychological treatments has never been investigated. Methods One hundred sixty MDD patients were partially randomized to either inter-personal counseling (IPC) or antidepressants. The primary outcome was remission at week 8. Five serotonergic polymorphisms were investigated (COMT rs4680, HTR1A rs6295, HTR2A rs2224721, HTR2A rs7997012 and SLC6A4 rs421417). Results IPC (n=43) and antidepressant (n=117) treated patients did not show any difference in remission rates at week 8 (corrected for baseline severity, age and center). None of the studied gene variants impacted on response and remission rates at week 8 neither in the IPC nor in the antidepressant group. An analysis of the whole sample showed a trend of association between rs7997012 AA genotype and a better treatment outcome. Conclusion Our study confirms that IPC is an effective psychological intervention comparable to antidepressants in mild-moderate MDD. Polymorphisms related to the serotonin system did not exert a major effect on clinical outcomes in none of the treatment groups. PMID:23798967

The interaction between cannabis use and the Val158Met polymorphism of the COMT gene in psychosis: A transdiagnostic meta - analysis.

PubMed

Vaessen, Thomas Stephanus Johannes; de Jong, Lea; Schäfer, Annika Theresia; Damen, Thomas; Uittenboogaard, Aniek; Krolinski, Pauline; Nwosu, Chinyere Vicky; Pinckaers, Florentina Maria Egidius; Rotee, Iris Leah Marije; Smeets, Antonius Petrus Wilhelmus; Ermiş, Ayşegül; Kennedy, James L; Nieman, Dorien H; Tiwari, Arun; van Os, Jim; Drukker, Marjan

2018-01-01

Neither environmental nor genetic factors are sufficient to predict the transdiagnostic expression of psychosis. Therefore, analysis of gene-environment interactions may be productive. A meta-analysis was performed using papers investigating the interaction between cannabis use and catechol-O-methyl transferase (COMT) polymorphism Val158Met (COMTVal158Met). PubMed, Embase, PsychInfo. All observational studies assessing the interaction between COMTVal158Met and cannabis with any psychosis or psychotic symptoms measure as an outcome. A meta-analysis was performed using the Meta-analysis of Observational Studies in Epidemiology guidelines and forest plots were generated. Thirteen articles met the selection criteria: 7 clinical studies using a case-only design, 3 clinical studies with a dichotomous outcome, and 3 studies analysing a continuous outcome of psychotic symptoms below the threshold of psychotic disorder. The three study types were analysed separately. Validity of the included studies was assessed using "A Cochrane Risk of Bias Assessment Tool: for Non-Randomized Studies of Interventions". For case-only studies, a significant interaction was found between cannabis use and COMTVal158Met, with an OR of 1.45 (95% Confidence Interval = 1.05-2.00; Met/Met as the risk genotype). However, there was no evidence for interaction in either the studies including dichotomous outcomes (B = -0.51, 95% Confidence Interval -1.72, 0.70) or the studies including continuous outcomes (B = -0.04 95% Confidence Interval -0.16-0.08). A substantial part of the included studies used the case-only design, which has lower validity and tends to overestimate true effects. The interaction term between cannabis use and COMTVal158Met was only statistically significant in the case-only studies, but not in studies using other clinical or non-clinical psychosis outcomes. Future additional high quality studies might change current perspectives, yet currently evidence for the interaction remains unconvincing.

Perinatal asphyxia alters neuregulin-1 and COMT gene expression in the medial prefrontal cortex in rats.

PubMed

Wakuda, Tomoyasu; Iwata, Keiko; Iwata, Yasuhide; Anitha, Ayyappan; Takahashi, Taro; Yamada, Kohei; Vasu, Mahesh Mundalil; Matsuzaki, Hideo; Suzuki, Katsuaki; Mori, Norio

2015-01-02

Epidemiological studies suggest that perinatal complications, particularly hypoxia-related ones, increase the risk of schizophrenia. Recent genetic studies of the disorder have identified several putative susceptibility genes, some of which are known to be regulated by hypoxia. It can be postulated therefore that birth complications that cause hypoxia in the fetal brain may be associated with a dysregulation in the expression of some of the schizophrenia candidate genes. To test this, we used an animal model of perinatal asphyxia, in which rat pups were exposed to 15 min of intrauterine anoxia during Caesarean section birth, and examined the expression of mRNA of five of the putative susceptibility genes (NRG1, ErbB4, AKT1, COMT and BDNF) by real-time quantitative PCR in the medial prefrontal cortex (mPFC) and the hippocampus at 6 and 12 weeks after birth. The expression of NRG1 mRNA was significantly decreased in the mPFC, but not in the hippocampus, at 6 and 12 weeks after birth. In addition, a significant increase in COMT mRNA expression was observed in the mPFC at 12 weeks. The alteration in mRNA levels of NRG1 and COMT was not associated with a change in their protein levels. These results suggest that perinatal asphyxia may lead to disturbances in the PFC, which in turn may exert a long-lasting influence on the expression of specific genes, such as NRG1 and COMT. Our results also suggest that translational interruption may occur in this model of perinatal asphyxia. Copyright © 2014 Elsevier Inc. All rights reserved.

Working memory brain activity and capacity link MAOA polymorphism to aggressive behavior during development

PubMed Central

Ziermans, T; Dumontheil, I; Roggeman, C; Peyrard-Janvid, M; Matsson, H; Kere, J; Klingberg, T

2012-01-01

A developmental increase in working memory capacity is an important part of cognitive development, and low working memory (WM) capacity is a risk factor for developing psychopathology. Brain activity represents a promising endophenotype for linking genes to behavior and for improving our understanding of the neurobiology of WM development. We investigated gene–brain–behavior relationships by focusing on 18 single-nucleotide polymorphisms (SNPs) located in six dopaminergic candidate genes (COMT, SLC6A3/DAT1, DBH, DRD4, DRD5, MAOA). Visuospatial WM (VSWM) brain activity, measured with functional magnetic resonance imaging, and VSWM capacity were assessed in a longitudinal study of typically developing children and adolescents. Behavioral problems were evaluated using the Child Behavior Checklist (CBCL). One SNP (rs6609257), located ∼6.6 kb downstream of the monoamine oxidase A gene (MAOA) on human chromosome X, significantly affected brain activity in a network of frontal, parietal and occipital regions. Increased activity in this network, but not in caudate nucleus or anterior prefrontal regions, was correlated with VSWM capacity, which in turn predicted externalizing (aggressive/oppositional) symptoms, with higher WM capacity associated with fewer externalizing symptoms. There were no direct significant correlations between rs6609257 and behavioral symptoms. These results suggest a mediating role of WM brain activity and capacity in linking the MAOA gene to aggressive behavior during development. PMID:22832821

Distribution of genetic polymorphisms of genes encoding drug metabolizing enzymes & drug transporters - a review with Indian perspective.

PubMed

Umamaheswaran, Gurusamy; Kumar, Dhakchinamoorthi Krishna; Adithan, Chandrasekaran

2014-01-01

Phase I and II drug metabolizing enzymes (DME) and drug transporters are involved in the absorption, distribution, metabolism as well as elimination of many therapeutic agents, toxins and various pollutants. Presence of genetic polymorphisms in genes encoding these proteins has been associated with marked inter-individual variability in their activity that could result in variation in drug response, toxicity as well as in disease predisposition. The emergent field pharmacogenetics and pharmacogenomics (PGx) is a promising discipline, as it predicts disease risk, selection of proper medication with regard to response and toxicity, and appropriate drug dosage guidance based on an individual's genetic make-up. Consequently, genetic variations are essential to understand the ethnic differences in disease occurrence, development, prognosis, therapeutic response and toxicity. For that reason, it is necessary to establish the normative frequency of these genes in a particular population before unraveling the genotype-phenotype associations. Although a fair amount of allele frequency data are available in Indian populations, the existing pharmacogenetic data have not been compiled into a database. This review was intended to compile the normative frequency distribution of the variants of genes encoding DMEs (CYP450s, TPMT, GSTs, COMT, SULT1A1, NAT2 and UGTs) and transporter proteins (MDR1, OCT1 and SLCO1B1) with Indian perspective.

Can heterogeneity of chronic sickle-cell disease pain be explained by genomics? A literature review.

PubMed

Adegbola, Maxine A

2009-07-01

This literature review explores the potential of genomics to explain, or at least contribute to the discussion about, heterogeneity in chronic pain in sickle-cell disease (SCD). Adults with SCD, a single-gene disorder, are living longer than in years past, yet report being burdened by chronic pain. With only a few studies on chronic pain in this population, the epidemiology is unclear. However, research in the area of pain genetics continues to advance since the conclusion of the Human Genome Project. Two pain susceptibility genes, catechol-O-methyltransferase (COMT) and cytochrome P450, have, to date, been discovered that can increase individual susceptibility to the development of chronic pain. A search was conducted in PubMed, CINAHL, and EBSCO using the terms "sickle cell,'' "chronic pain,'' "polymorphism,'' "genetics,'' "pain genetics,'' "human,'' "adult,'' "association studies,'' and "pain susceptibility genes'' to search for articles published between 1970 and 2008. Chronic pain generally is more prevalent and severe than previously reported, and individuals with SCD report daily pain. The genomic era has made it possible for scientists to identify pain susceptibility genes that contribute to variability in the interindividual experience of chronic pain. Nurses are well positioned to generate and translate genomic research, thus improving care delivery. Such research may lead to the identification of polymorphisms associated with pain sensitivity in individuals with SCD.

The role of clinical variables, neuropsychological performance and SLC6A4 and COMT gene polymorphisms on the prediction of early response to fluoxetine in major depressive disorder.

PubMed

Gudayol-Ferré, Esteve; Herrera-Guzmán, Ixchel; Camarena, Beatriz; Cortés-Penagos, Carlos; Herrera-Abarca, Jorge E; Martínez-Medina, Patricia; Cruz, David; Hernández, Sandra; Genis, Alma; Carrillo-Guerrero, Mariana Y; Avilés Reyes, Rubén; Guàrdia-Olmos, Joan

2010-12-01

Major depressive disorder (MDD) is treated with antidepressants, but only between 50% and 70% of the patients respond to the initial treatment. Several authors suggested different factors that could predict antidepressant response, including clinical, psychophysiological, neuropsychological, neuroimaging, and genetic variables. However, these different predictors present poor prognostic sensitivity and specificity by themselves. The aim of our work is to study the possible role of clinical variables, neuropsychological performance, and the 5HTTLPR, rs25531, and val108/58Met COMT polymorphisms in the prediction of the response to fluoxetine after 4weeks of treatment in a sample of patient with MDD. 64 patients with MDD were genotyped according to the above-mentioned polymorphisms, and were clinically and neuropsychologically assessed before a 4-week fluoxetine treatment. Fluoxetine response was assessed by using the Hamilton Depression Rating Scale. We carried out a binary logistic regression model for the potential predictive variables. Out of the clinical variables studied, only the number of anxiety disorders comorbid with MDD have predicted a poor response to the treatment. A combination of a good performance in variables of attention and low performance in planning could predict a good response to fluoxetine in patients with MDD. None of the genetic variables studied had predictive value in our model. The possible placebo effect has not been controlled. Our study is focused on response prediction but not in remission prediction. Our work suggests that the combination of the number of comorbid anxiety disorders, an attentional variable, and two planning variables makes it possible to correctly classify 82% of the depressed patients who responded to the treatment with fluoxetine, and 74% of the patients who did not respond to that treatment. Copyright © 2010 Elsevier B.V. All rights reserved.

Interaction between childhood adversity and functional polymorphisms in the dopamine pathway on first-episode psychosis.

PubMed

Trotta, Antonella; Iyegbe, Conrad; Yiend, Jenny; Dazzan, Paola; David, Anthony S; Pariante, Carmine; Mondelli, Valeria; Colizzi, Marco; Murray, Robin M; Di Forti, Marta; Fisher, Helen L

2018-04-10

There is consistent evidence of a cumulative relationship between childhood adversity and psychosis, with number of adversities experienced increasing the probability of psychosis onset. It is possible that genetic factors moderate the association between childhood adversity and psychosis, potentially by influencing how an individual reacts biologically and/or psychologically following exposure to adversity, in such a way as to set them off on the path to psychosis. However, identifying the specific genetic variants involved and how they interact with childhood adversity remains challenging. We examined whether the association between cumulative exposure to childhood adversity and development of psychotic disorder was moderated by the COMT Val 158 Met, AKT1 rs2494732 or DRD2 rs1076560 polymorphisms, known to affect dopamine levels. Participants were 285 first-presentation psychosis cases and 256 geographically-matched controls drawn from the Genetics and Psychosis (GAP) study. Childhood adversity was assessed using the Childhood Experience of Care and Abuse Questionnaire (CECA.Q) and blood- and cheek-derived genotype data were collected. Our findings revealed no main effect of COMT Val 158 Met, AKT1 rs2494732 and DRD2 rs1076560 polymorphisms on psychosis case status or reports of childhood adversity. Individuals reporting a history of multiple adversities were more likely to be psychosis patients than controls, regardless of their genetic risk. There was no evidence of candidate genotype by childhood adversity interactions in relation to psychosis onset. These findings did not provide evidence of a possible role of COMT Val 158 Met, AKT1 rs2494732 or DRD2 rs1076560 genotypes in modifying the association between childhood adversity and onset of psychosis. Copyright © 2018 Elsevier B.V. All rights reserved.

The impact of the Val158Met catechol-O-methyltransferase genotype on neural correlates of sad facial affect processing in patients with bipolar disorder and their relatives.

PubMed

Lelli-Chiesa, G; Kempton, M J; Jogia, J; Tatarelli, R; Girardi, P; Powell, J; Collier, D A; Frangou, S

2011-04-01

The Met allele of the catechol-O-methyltransferase (COMT) valine-to-methionine (Val158Met) polymorphism is known to affect dopamine-dependent affective regulation within amygdala-prefrontal cortical (PFC) networks. It is also thought to increase the risk of a number of disorders characterized by affective morbidity including bipolar disorder (BD), major depressive disorder (MDD) and anxiety disorders. The disease risk conferred is small, suggesting that this polymorphism represents a modifier locus. Therefore our aim was to investigate how the COMT Val158Met may contribute to phenotypic variation in clinical diagnosis using sad facial affect processing as a probe for its neural action. We employed functional magnetic resonance imaging to measure activation in the amygdala, ventromedial PFC (vmPFC) and ventrolateral PFC (vlPFC) during sad facial affect processing in family members with BD (n=40), MDD and anxiety disorders (n=22) or no psychiatric diagnosis (n=25) and 50 healthy controls. Irrespective of clinical phenotype, the Val158 allele was associated with greater amygdala activation and the Met158 allele with greater signal change in the vmPFC and vlPFC. Signal changes in the amygdala and vmPFC were not associated with disease expression. However, in the right vlPFC the Met158 allele was associated with greater activation in all family members with affective morbidity compared with relatives without a psychiatric diagnosis and healthy controls. Our results suggest that the COMT Val158Met polymorphism has a pleiotropic effect within the neural networks subserving emotional processing. Furthermore the Met158 allele further reduces cortical efficiency in the vlPFC in individuals with affective morbidity.

The Role of Catechol-O-Methyl Transferase Val(108/158)Met Polymorphism (rs4680) in the Effect of Green Tea on Resting Energy Expenditure and Fat Oxidation: A Pilot Study

PubMed Central

Hursel, Rick; Janssens, Pilou L. H. R.; Bouwman, Freek G.; Mariman, Edwin C.; Westerterp-Plantenga, Margriet S.

2014-01-01

Introduction Green tea(GT) is able to increase energy expenditure(EE) and fat oxidation(FATox) via inhibition of catechol-O-methyl transferase(COMT) by catechins. However, this does not always appear unanimously because of large inter-individual variability. This may be explained by different alleles of the functional COMT Val108/158Met polymorphism that are associated with COMT enzyme activity; high-activity enzyme, COMTH(Val/Val genotype), and low-activity COMTL(Met/Met genotype). Methods Fourteen Caucasian subjects (BMI: 22.2±2.3 kg/m2, age: 21.4±2.2 years) of whom 7 with the COMTH-genotype and 7 with the COMTL-genotype were included in a randomized, cross-over study in which EE and substrate oxidation were measured with a ventilated-hood system after decaffeinated GT and placebo(PL) consumption. Results At baseline, EE, RQ, FATox and carbohydrate oxidation(CHOox) did not differ between groups. Significant interactions were observed between COMT genotypes and treatment for RQ, FATox and CHOox (p<0.05). After GT vs. PL, EE(GT: 62.2 vs. PL: 35.4 kJ.3.5 hrs; p<0.01), RQ(GT: 0.80 vs. PL: 0.83; p<0.01), FATox(GT: 18.3 vs. PL: 15.3 g/d; p<0.001) and CHOox(GT: 18.5 vs. PL: 24.3 g/d; p<0.001) were significantly different for subjects carrying the COMTH genotype, but not for subjects carrying the COMTL genotype (EE, GT: 60.3 vs. PL: 51.7 kJ.3.5 hrs; NS), (RQ, GT: 0.81 vs. PL: 0.81; NS), (FATox, GT: 17.3 vs. PL: 17.0 g/d; NS), (CHOox, GT: 22.1 vs. PL: 21.4 g/d; NS). Conclusion Subjects carrying the COMTH genotype increased energy expenditure and fat-oxidation upon ingestion of green tea catechins vs, placebo, whereas COMTL genotype carriers reacted similarly to GT and PL ingestion. The differences in responses were due to the different responses on PL ingestion, but similar responses to GT ingestion, pointing to different mechanisms. The different alleles of the functional COMT Val108/158Met polymorphism appear to play a role in the inter-individual variability for EE and FATox after GT treatment. Trial Registration Nederlands Trial register NTR1918 PMID:25238062

Simultaneous Down-Regulation of Caffeic/5-Hydroxy Ferulic Acid-O-Methyltransferase I and Cinnamoyl-Coenzyme A Reductase in the Progeny from a Cross between Tobacco Lines Homozygous for Each Transgene. Consequences for Plant Development and Lignin Synthesis1

PubMed Central

Pinçon, Gaelle; Chabannes, Matthieu; Lapierre, Catherine; Pollet, Brigitte; Ruel, Katia; Joseleau, Jean-Paul; Boudet, Alain M.; Legrand, Michel

2001-01-01

Inhibition of specific lignin biosynthetic steps by antisense strategy has previously been shown to alter lignin content and/or structure. In this work, homozygous tobacco (Nicotiana tabacum) lines transformed with cinnamoyl-coenzyme A reductase (CCR) or caffeic acid/5-hydroxy ferulic acid-O-methyltransferase I (COMT I) antisense sequences have been crossed and enzyme activities, lignin synthesis, and cell wall structure of the progeny have been analyzed. In single transformed parents, CCR inhibition did not affect COMT I expression, whereas marked increases in CCR activity were observed in COMT I antisense plants, suggesting potential cross talk between some genes of the pathway. In the progeny, both CCR and COMT I activities were shown to be markedly decreased due to the simultaneous repression of the two genes. In these double transformants, the lignin profiles were dependent on the relative extent of down-regulation of each individual enzyme. For the siblings issued from a strongly repressed antisense CCR parent, the lignin patterns mimicked the patterns obtained in single transformants with a reduced CCR activity. In contrast, the specific lignin profile of COMT I repression could not be detected in double transformed siblings. By transmission electron microscopy some cell wall loosening was detected in the antisense CCR parent but not in the antisense COMT I parent. In double transformants, immunolabeling of non-condensed guaiacyl-syringyl units was weaker and revealed changes in epitope distribution that specifically affected vessels. Our results more widely highlight the impact of culture conditions on phenotypes and gene expression of transformed plants. PMID:11351078

Joint effects of smoking and gene variants involved in sex steroid metabolism on hot flashes in late reproductive-age women.

PubMed

Butts, Samantha F; Freeman, Ellen W; Sammel, Mary D; Queen, Kaila; Lin, Hui; Rebbeck, Timothy R

2012-06-01

Although smoking has a known association with hot flashes, the factors distinguishing smokers at greatest risk for menopausal symptoms have not been well delineated. Recent evidence supports a relationship between menopausal symptoms and variants in several genes encoding enzymes that metabolize substrates such as sex steriods, xenobiotics, and catechols. It is currently not known whether the impact of smoking on hot flashes is modified by the presence of such variants. The objective of the study was to investigate the relationship between smoking and hot flash occurrence as a function of genetic variation in sex steroid-metabolizing enzymes. A cross-sectional analysis of data from the Penn Ovarian Aging study, an ongoing population-based cohort of late reproductive-aged women, was performed. Smoking behavior was characterized. Single-nucleotide polymorphisms in five genes were investigated: COMT Val158Met (rs4680), CYP1A2*1F (rs762551), CYP1B1*4 (Asn452Ser, rs1800440), CYP1B1*3 (Leu432Val, rs1056836), and CYP3A4*1B (rs2740574). Compared with nonsmokers, European-American COMT Val158Met double-variant carriers who smoked had increased odds of hot flashes [adjusted odds ratio (AOR) 6.15, 95% confidence interval (CI) 1.32-28.78)]; European-American COMT Val158Met double-variant carriers who smoked heavily had more frequent moderate or severe hot flashes than nonsmokers (AOR 13.7, 95% CI 1.2-154.9). European-American CYP 1B1*3 double-variant carriers who smoked described more frequent moderate or severe hot flashes than nonsmoking (AOR 20.6, 95% CI 1.64-257.93) and never-smoking (AOR 20.59, 95% CI 1.39-304.68) carriers, respectively. African-American single-variant CYP 1A2 carriers who smoked were more likely to report hot flashes than the nonsmoking carriers (AOR 6.16, 95% CI 1.11-33.91). This is the first report demonstrating the effects of smoking within the strata of gene variants involved in sex steroid metabolism on hot flashes in late reproductive-age women. The identification of individuals with a genetic susceptibility to smoking-related menopausal symptoms could contribute to interventions targeted at reducing reproductive morbidity both in the menopause and across the reproductive life course.

Molecular genetic mechanisms of allelic specific regulation of murine Comt expression

PubMed Central

Segall, Samantha K.; Shabalina, Svetlana A.; Meloto, Carolina B.; Wen, Xia; Cunningham, Danielle; Tarantino, Lisa M.; Wiltshire, Tim; Gauthier, Josée; Tohyama, Sarasa; Martin, Loren J.; Mogil, Jeffrey S.; Diatchenko, Luda

2015-01-01

Abstract A functional allele of the mouse catechol-O-methyltransferase (Comt) gene is defined by the insertion of a B2 short interspersed repeat element in its 3′-untranslated region (UTR). This allele has been associated with a number of phenotypes, such as pain and anxiety. In comparison with mice carrying the ancestral allele (Comt+), ComtB2i mice show higher Comt mRNA and enzymatic activity levels. Here, we investigated the molecular genetic mechanisms underlying this allelic specific regulation of Comt expression. Insertion of the B2 element introduces an early polyadenylation signal generating a shorter Comt transcript, in addition to the longer ancestral mRNA. Comparative analysis and in silico prediction of Comt mRNA potential targets within the transcript 3′ to the B2 element was performed and allowed choosing microRNA (miRNA) candidates for experimental screening: mmu-miR-3470a, mmu-miR-3470b, and mmu-miR-667. Cell transfection with each miRNA downregulated the expression of the ancestral transcript and COMT enzymatic activity. Our in vivo experiments showed that mmu-miR-667-3p is strongly correlated with decreasing amounts of Comt mRNA in the brain, and lentiviral injections of mmu-miR-3470a, mmu-miR-3470b, and mmu-miR-667 increase hypersensitivity in the mouse formalin model, consistent with reduced COMT activity. In summary, our data demonstrate that the Comt+ transcript contains regulatory miRNA signals in its 3′-untranslated region leading to mRNA degradation; these signals, however, are absent in the shorter transcript, resulting in higher mRNA expression and activity levels. PMID:26067582

Modulation of Estrogen-Depurinating DNA Adducts by Sulforaphane for Breast Cancer

DTIC Science & Technology

2014-12-01

adducts. NQO1 reduces CE-3,4- 5 quinones back to catechols and GST catalyzes the conjugation of CE-3,4-quinones with glutathione, whereas COMT ... COMT , GSTA1 and β-actin (Sigma) antibodies were made in blocking solution (5% non-fat dry milk in Tris-buffered saline). The blots were incubated...other genes known to influence E2 metabolism, namely CYP1B1 and COMT , were observed (Figure 4A). These inductions exhibited a dose response, with

Association Between Genetic Polymorphisms and Pain Sensitivity in Patients with Hip Osteoarthritis.

PubMed

Olesen, Anne E; Nielsen, Lecia M; Feddersen, Søren; Erlenwein, Joachim; Petzke, Frank; Przemeck, Michael; Christrup, Lona L; Drewes, Asbjørn M

2018-06-01

Factors such as age, gender, and genetic polymorphisms may explain individual differences in pain phenotype. Genetic associations with pain sensitivity have previously been investigated in osteoarthritis patients, with a focus on the P2X7, TRPV1, and TACR1 genes. However, other genes may play a role as well. Osteoarthritis is a common joint disease, and many patients suffering from this disease are thought to have increased sensitivity to noxious stimuli resulting from sensitization in the nociceptive system. The aim of this study was to investigate if genetic variants of mu, kappa, and delta opioid receptor genes (OPRM1, OPRK1, and OPRD1) and the catechol-O-methyltransferase gene (COMT) influenced the pain phenotype in patients with osteoarthritis. The frequencies of 17 polymorphisms were examined. Pain sensitivity was assessed preoperatively by (1) hip rotation, (2) contact heat stimulation, (3) conditioned pain modulation effect, and (4) pressure stimulation at the tibia in both the affected and the unaffected leg. Ninety-two patients (mean age 66 years) with unilateral hip osteoarthritis were included in the study. Carriage of the OPRM1 rs589046T allele was found to be associated with increased pain ratings during hip rotation (P = 0.04) and increased conditioned pain modulation (P = 0.049). Carriage of the OPRD1 rs2234918C allele was found to be associated with an increased pain detection threshold to contact heat stimulation (P = 0.001). No other associations were found (all P > 0.05). Results from the present study suggest that, in patients with hip osteoarthritis, genetic variants in OPRM1 and OPRD1 may contribute to the pain phenotype. © 2017 World Institute of Pain.

Genetic polymorphisms and their association with the prevalence and severity of chronic postsurgical pain: a systematic review.

PubMed

Hoofwijk, D M N; van Reij, R R I; Rutten, B P; Kenis, G; Buhre, W F; Joosten, E A

2016-12-01

Although several patient characteristic, clinical, and psychological risk factors for chronic postsurgical pain (CPSP) have been identified, genetic variants including single nucleotide polymorphisms have also become of interest as potential risk factors for the development of CPSP. The aim of this review is to summarize the current evidence on genetic polymorphisms associated with the prevalence and severity of CPSP in adult patients. A systematic review of the literature was performed, and additional literature was obtained by reference tracking. The primary outcome was CPSP, defined as pain at least 2 months after the surgery. Studies performed exclusively in animals were excluded. Out of the 1001 identified studies, 14 studies were selected for inclusion. These studies described 5269 participants in 17 cohorts. A meta-analysis was not possible because of heterogeneity of data and data analysis. Associations with the prevalence or severity of CPSP were reported for genetic variants in the COMT gene, OPRM1, potassium channel genes, GCH1, CACNG, CHRNA6, P2X7R, cytokine-associated genes, human leucocyte antigens, DRD2, and ATXN1 CONCLUSIONS: Research on the topic of genetic variants associated with CPSP is still in its initial phase. Hypothesis-free, genome-wide association studies on large cohorts are needed in this field. In addition, future studies may also integrate genetic risk factors and patient characteristic, clinical, and psychological predictors for CPSP. © The Author 2016. Published by Oxford University Press on behalf of the British Journal of Anaesthesia. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

HsfA1a upregulates melatonin biosynthesis to confer cadmium tolerance in tomato plants.

PubMed

Cai, Shu-Yu; Zhang, Yun; Xu, You-Ping; Qi, Zhen-Yu; Li, Meng-Qi; Ahammed, Golam Jalal; Xia, Xiao-Jian; Shi, Kai; Zhou, Yan-Hong; Reiter, Russel J; Yu, Jing-Quan; Zhou, Jie

2017-03-01

Melatonin regulates broad aspects of plant responses to various biotic and abiotic stresses, but the upstream regulation of melatonin biosynthesis by these stresses remains largely unknown. Herein, we demonstrate that transcription factor heat-shock factor A1a (HsfA1a) conferred cadmium (Cd) tolerance to tomato plants, in part through its positive role in inducing melatonin biosynthesis under Cd stress. Analysis of leaf phenotype, chlorophyll content, and photosynthetic efficiency revealed that silencing of the HsfA1a gene decreased Cd tolerance, whereas its overexpression enhanced plant tolerance to Cd. HsfA1a-silenced plants exhibited reduced melatonin levels, and HsfA1a overexpression stimulated melatonin accumulation and the expression of the melatonin biosynthetic gene caffeic acid O-methyltransferase 1 (COMT1) under Cd stress. Both an in vitro electrophoretic mobility shift assay and in vivo chromatin immunoprecipitation coupled with qPCR analysis revealed that HsfA1a binds to the COMT1 gene promoter. Meanwhile, Cd stress induced the expression of heat-shock proteins (HSPs), which was compromised in HsfA1a-silenced plants and more robustly induced in HsfA1a-overexpressing plants under Cd stress. COMT1 silencing reduced HsfA1a-induced Cd tolerance and melatonin accumulation in HsfA1a-overexpressing plants. Additionally, the HsfA1a-induced expression of HSPs was partially compromised in COMT1-silenced wild-type or HsfA1a-overexpressing plants under Cd stress. These results demonstrate that HsfA1a confers Cd tolerance by activating transcription of the COMT1 gene and inducing accumulation of melatonin that partially upregulates expression of HSPs. © 2017 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Methylation polymorphism influences practice effects in children during attention tasks1

PubMed Central

Voelker, Pascale; Sheese, Brad E.; Rothbart, Mary K.; Posner, Michael I.

2017-01-01

Epigenetic mechanisms mediate the influence of experience on gene expression. Methylation is a principal method for inducing epigenetic effects on DNA. In this paper, we examine alleles of the methylenetetrahydrofolate reductase (MTHFR) gene that vary enzyme activity, altering the availability of the methyl donor and thus changing the efficiency of methylation. We hypothesized that alleles of the MTHFR gene would influence behavior in an attention related task in conjunction with genes known to influence attention. We found that 7-year-old children homozygous for the C allele of MTHFR in interaction with the catechol O-methyltransferase (COMT) gene showed greater improvement in overall reaction time (RT) and in conflict resolution with practice on the Attention Network Test (ANT). This finding indicates that methylation may operate on or through genes that influence executive network operation. However, MTHFR T allele carriers showed faster overall RT and conflict resolution. Some children showed an initial improvement in ANT RT followed by a decline in performance, and we found that alleles of the dopamine beta-hydroxylase (DBH) gene were related to this performance decline. These results suggest a genetic dissociation between improvement while learning a skill and reduction in performance with continued practice. PMID:27050482

Genetic variation throughout the folate metabolic pathway influences negative symptom severity in schizophrenia.

PubMed

Roffman, Joshua L; Brohawn, David G; Nitenson, Adam Z; Macklin, Eric A; Smoller, Jordan W; Goff, Donald C

2013-03-01

Low serum folate levels previously have been associated with negative symptom risk in schizophrenia, as has the hypofunctional 677C>T variant of the MTHFR gene. This study examined whether other missense polymorphisms in folate-regulating enzymes, in concert with MTHFR, influence negative symptoms in schizophrenia, and whether total risk allele load interacts with serum folate status to further stratify negative symptom risk. Medicated outpatients with schizophrenia (n = 219), all of European origin and some included in a previous report, were rated with the Positive and Negative Syndrome Scale. A subset of 82 patients also underwent nonfasting serum folate testing. Patients were genotyped for the MTHFR 677C>T (rs1801133), MTHFR 1298A>C (rs1801131), MTR 2756A>G (rs1805087), MTRR 203A>G (rs1801394), FOLH1 484T>C (rs202676), RFC 80A>G (rs1051266), and COMT 675G>A (rs4680) polymorphisms. All genotypes were entered into a linear regression model to determine significant predictors of negative symptoms, and risk scores were calculated based on total risk allele dose. Four variants, MTHFR 677T, MTR 2756A, FOLH1 484C, and COMT 675A, emerged as significant independent predictors of negative symptom severity, accounting for significantly greater variance in negative symptoms than MTHFR 677C>T alone. Total allele dose across the 4 variants predicted negative symptom severity only among patients with low folate levels. These findings indicate that multiple genetic variants within the folate metabolic pathway contribute to negative symptoms of schizophrenia. A relationship between folate level and negative symptom severity among patients with greater genetic vulnerability is biologically plausible and suggests the utility of folate supplementation in these patients.

Catechol-O-methyltransferase genotype modifies executive functioning and prefrontal functional connectivity in women with anorexia nervosa.

PubMed

Favaro, Angela; Clementi, Maurizio; Manara, Renzo; Bosello, Romina; Forzan, Monica; Bruson, Alice; Tenconi, Elena; Degortes, Daniela; Titton, Francesca; Di Salle, Francesco; Santonastaso, Paolo

2013-07-01

Anorexia nervosa is characterized by high levels of perseveration and inflexibility, which interfere with successful treatments. Dopamine (DA) signalling seems to play a key role in modulating the prefrontal cortex, since both DA deficiency and excess nega tively influence the efficiency of cognitive functions. The present study explores the effect of a functional polymorphism (Val158Met) in the catechol-O-methyltransferase (COMT) gene on the set-shifting abilities and prefrontal functional connectivity of patients with anorexia nervosa. All participants performed the Wisconsin Card Sorting Task, and a subsample underwent resting-state functional magnetic resonance imaging. We included 166 patients with DSM-IV lifetime anorexia nervosa and 140 healthy women in our study. Both underweight and weight-recovered patients with anorexia nervosa showed high levels of perseveration, but only in the underweight group did the Val158Met polymorphism affect cognitive performance, showing the U-shaped curve characteristic of increased DA signalling in the prefrontal cortex. Underweight patients with anorexia nervosa who are Met homozygotes had significantly higher levels of perseveration and increased prefrontal functional connectivity than underweight patients in the other genotype groups, indicating abnormal regional cortical processing. Although our data show that grey matter reduction in starving patients with anorexia nervosa did not explain our findings, the cross-sectional design of the present study did not allow us to distinguish between the effects of starvation and those of low estrogen levels. Starvation affects DA release in the prefrontal cortex of patients with anorexia nervosa with different effects on executive functioning and prefrontal functional connectivity according to the COMT genotype. This observation has several therapeutic implications that need to be addressed by future studies.

Catechol-O-methyltransferase genotype modifies executive functioning and prefrontal functional connectivity in women with anorexia nervosa

PubMed Central

Favaro, Angela; Clementi, Maurizio; Manara, Renzo; Bosello, Romina; Forzan, Monica; Bruson, Alice; Tenconi, Elena; Degortes, Daniela; Titton, Francesca; Di Salle, Francesco; Santonastaso, Paolo

2013-01-01

Background Anorexia nervosa is characterized by high levels of perseveration and inflexibility, which interfere with successful treatments. Dopamine (DA) signalling seems to play a key role in modulating the prefrontal cortex, since both DA deficiency and excess negatively influence the efficiency of cognitive functions. The present study explores the effect of a functional polymorphism (Val158Met) in the catechol-O-methyltransferase (COMT) gene on the set-shifting abilities and prefrontal functional connectivity of patients with anorexia nervosa. Methods All participants performed the Wisconsin Card Sorting Task, and a subsample underwent resting-state functional magnetic resonance imaging. Results We included 166 patients with DSM-IV lifetime anorexia nervosa and 140 healthy women in our study. Both underweight and weight-recovered patients with anorexia nervosa showed high levels of perseveration, but only in the underweight group did the Val158Met polymorphism affect cognitive performance, showing the U-shaped curve characteristic of increased DA signalling in the prefrontal cortex. Underweight patients with anorexia nervosa who are Met homozygotes had significantly higher levels of perseveration and increased prefrontal functional connectivity than underweight patients in the other genotype groups, indicating abnormal regional cortical processing. Limitations Although our data show that grey matter reduction in starving patients with anorexia nervosa did not explain our findings, the cross-sectional design of the present study did not allow us to distinguish between the effects of starvation and those of low estrogen levels. Conclusion Starvation affects DA release in the prefrontal cortex of patients with anorexia nervosa with different effects on executive functioning and prefrontal functional connectivity according to the COMT genotype. This observation has several therapeutic implications that need to be addressed by future studies. PMID:23046831

Genetic Risk for Age-Related Cognitive Impairment Does Not Predict Cognitive Performance in Middle Age.

PubMed

Korthauer, Laura E; Awe, Elizabeth; Frahmand, Marijam; Driscoll, Ira

2018-05-26

Alzheimer's disease (AD) is characterized by memory loss and executive dysfunction, which correspond to structural changes to the medial temporal lobes (MTL) and prefrontal cortex (PFC), respectively. Given the overlap in cognitive deficits between healthy aging and the earliest stages of AD, early detection of AD remains a challenge. The goal of the present study was to study MTL- and PFC-dependent cognitive functioning in middle-aged individuals at genetic risk for AD or cognitive impairment who do not currently manifest any clinical symptoms. Participants (N = 150; aged 40-60 years) underwent genotyping of 47 single nucleotide polymorphisms (SNPs) in six genes previously associated with memory or executive functioning: APOE, SORL1, BDNF, TOMM40, KIBRA, and COMT. They completed two MTL-dependent tasks, the virtual Morris Water Task (vMWT) and transverse patterning discriminations task (TPDT), and the PFC-dependent reversal learning task. Although age was associated with poorer performance on the vMWT and TPDT within this middle-aged sample, there were no genotype-associated differences in cognitive performance. Although the vMWT and TPDT may be sensitive to age-related changes in cognition, carriers of APOE, SORL1, BDNF, TOMM40, KIBRA, and COMT risk alleles do not exhibit alteration in MTL- and PFC-dependent functioning in middle age compared to non-carriers.

Genetic predictor of working memory and prefrontal function in women with HIV.

PubMed

Sundermann, Erin E; Bishop, Jeffrey R; Rubin, Leah H; Little, Deborah M; Meyer, Vanessa J; Martin, Eileen; Weber, Kathleen; Cohen, Mardge; Maki, Pauline M

2015-02-01

The Val158Met (rs4680) single-nucleotide polymorphism (SNP) of the catechol-O-methyltransferase gene (COMT) influences executive function and prefrontal function through its effect on dopamine (DA) metabolism. Both HIV and the Val allele of the Val158Met SNP are associated with compromised executive function and inefficient prefrontal function. The present study used behavioral and neuroimaging techniques to determine independent and interactive associations between HIV serostatus and COMT genotype on working memory and prefrontal function in women. For the behavioral study, 54 HIV-infected and 33 HIV-uninfected women completed the 0-, 1-, and 2-back conditions of the verbal N-back, a working memory test. For the imaging study, 36 women (23 HIV-infected, 13 HIV-uninfected) underwent functional magnetic resonance imaging (fMRI) assessments while completing the N-back task. HIV-infected women demonstrated significantly worse N-back performance compared with HIV-uninfected women (p < 0.05). A significant serostatus by genotype interaction (p < 0.01) revealed that, among Val/Val, but not Met allele carriers, HIV-infected women performed significantly worse than HIV-uninfected controls across N-back conditions (p < 0.01). Analogous to behavioral findings, a serostatus by genotype interaction revealed that HIV-infected Val/Val carriers showed significantly greater prefrontal activation compared with HIV-uninfected Val/Val carriers (p < 0.01). Conversely, HIV-uninfected Met allele carriers demonstrated significantly greater prefrontal activation compared with HIV-infected Met allele carriers. Findings suggest that the combination of HIV infection and the Val/Val COMT genotype leads to working memory deficits and altered prefrontal function in HIV-infected individuals.

Placebo analgesia and reward processing: integrating genetics, personality, and intrinsic brain activity.

PubMed

Yu, Rongjun; Gollub, Randy L; Vangel, Mark; Kaptchuk, Ted; Smoller, Jordan W; Kong, Jian

2014-09-01

Our expectations about an event can strongly shape our subjective evaluation and actual experience of events. This ability, applied to the modulation of pain, has the potential to affect therapeutic analgesia substantially and constitutes a foundation for non-pharmacological pain relief. A typical example of such modulation is the placebo effect. Studies indicate that placebo may be regarded as a reward, and brain activity in the reward system is involved in this modulation process. In the present study, we combined resting-state functional magnetic resonance imaging (rs-fMRI) measures, genotype at a functional COMT polymorphism (Val158Met), and personality measures in a model to predict the magnitude of placebo conditioning effect indicated by subjective pain rating reduction to calibrated noxious stimuli. We found that the regional homogeneity (ReHo), an index of local neural coherence, in the ventral striatum, was significantly associated with conditioning effects on pain rating changes. We also found that the number of Met alleles at the COMT polymorphism was linearly correlated to the suppression of pain. In a fitted regression model, we found the ReHo in the ventral striatum, COMT genotype, and Openness scores accounted for 59% of the variance in the change in pain ratings. The model was further tested using a separate data set from the same study. Our findings demonstrate the potential of combining resting-state connectivity, genetic information, and personality to predict placebo effect. Copyright © 2014 Wiley Periodicals, Inc.

COMT Genetic Reduction Produces Sexually Divergent Effects on Cortical Anatomy and Working Memory in Mice and Humans.

PubMed

Sannino, Sara; Gozzi, Alessandro; Cerasa, Antonio; Piras, Fabrizio; Scheggia, Diego; Managò, Francesca; Damiano, Mario; Galbusera, Alberto; Erickson, Lucy C; De Pietri Tonelli, Davide; Bifone, Angelo; Tsaftaris, Sotirios A; Caltagirone, Carlo; Weinberger, Daniel R; Spalletta, Gianfranco; Papaleo, Francesco

2015-09-01

Genetic variations in catechol-O-methyltransferase (COMT) that modulate cortical dopamine have been associated with pleiotropic behavioral effects in humans and mice. Recent data suggest that some of these effects may vary among sexes. However, the specific brain substrates underlying COMT sexual dimorphisms remain unknown. Here, we report that genetically driven reduction in COMT enzyme activity increased cortical thickness in the prefrontal cortex (PFC) and postero-parieto-temporal cortex of male, but not female adult mice and humans. Dichotomous changes in PFC cytoarchitecture were also observed: reduced COMT increased a measure of neuronal density in males, while reducing it in female mice. Consistent with the neuroanatomical findings, COMT-dependent sex-specific morphological brain changes were paralleled by divergent effects on PFC-dependent working memory in both mice and humans. These findings emphasize a specific sex-gene interaction that can modulate brain morphological substrates with influence on behavioral outcomes in healthy subjects and, potentially, in neuropsychiatric populations. © The Author 2014. Published by Oxford University Press. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.

Molecular cloning, characterization and expression of the caffeic acid O-methyltransferase (COMT) ortholog from kenaf (Hibiscus cannabinus)

USDA-ARS?s Scientific Manuscript database

We cloned the full-length of the gene putatively encoding caffeic acid O-methyltransferase (COMT) from kenaf (Hibiscus cannabinus L.) using degenerate primers and the RACE (rapid amplification of cDNA ends) method. Kenaf is an herbaceous and rapidly growing dicotyledonous plant with great potential ...

Genetics of Aggression in Alzheimer’s Disease (AD)

PubMed Central

Lukiw, Walter J.; Rogaev, Evgeny I.

2017-01-01

Alzheimer’s disease (AD) is a terminal, age-related neurological syndrome exhibiting progressive cognitive and memory decline, however AD patients in addition exhibit ancillary neuropsychiatric symptoms (NPSs) and these include aggression. In this communication we provide recent evidence for the mis-regulation of a small family of genes expressed in the human hippocampus that appear to be significantly involved in expression patterns common to both AD and aggression. DNA array- and mRNA transcriptome-based gene expression analysis and candidate gene association and/or genome-wide association studies (CGAS, GWAS) of aggressive attributes in humans have revealed a surprisingly small subset of six brain genes that are also strongly associated with altered gene expression patterns in AD. These genes encoded on five different chromosomes (chr) include the androgen receptor (AR; chrXq12), brain-derived neurotrophic factor (BDNF; chr11p14.1), catechol-O-methyl transferase (COMT; chr22q11.21), neuronal specific nitric oxide synthase (NOS1; chr12q24.22), dopamine beta-hydroxylase (DBH chr9q34.2) and tryptophan hydroxylase (TPH1, chr11p15.1 and TPH2, chr12q21.1). Interestingly, (i) the expression of three of these six genes (COMT, DBH, NOS1) are highly variable; (ii) three of these six genes (COMT, DBH, TPH1) are involved in DA or serotonin metabolism, biosynthesis and/or neurotransmission; and (iii) five of these six genes (AR, BDNF, COMT, DBH, NOS1) have been implicated in the development, onset and/or propagation of schizophrenia. The magnitude of the expression of genes implicated in aggressive behavior appears to be more pronounced in the later stages of AD when compared to MCI. These recent genetic data further indicate that the extent of cognitive impairment may have some bearing on the degree of aggression which accompanies the AD phenotype. PMID:28443016

Dopaminergic foundations of schizotypy as measured by the German version of the Oxford-Liverpool Inventory of Feelings and Experiences (O-LIFE)—a suitable endophenotype of schizophrenia

PubMed Central

Grant, Phillip; Kuepper, Yvonne; Mueller, Eva A.; Wielpuetz, Catrin; Mason, Oliver; Hennig, Juergen

2013-01-01

The concept of schizotypy or “psychosis proneness” captures individual differences in perceptual, cognitive, and affective experiences that may relate to a range of psychotic disorders. The concept is an important way to assess the contribution of pre-existing psychological and genetically based biological features to the development of illnesses such as schizophrenia (so called endophenotypes). The Oxford-Liverpool Inventory of Feelings and Experiences (O-LIFE) is a widely used multi-dimensional measure of the construct and consists of four scales which mirror several groups of psychotic symptoms: Unusual Experiences (UnEx; positive symptoms), Cognitive Disorganization (CogDis; cognitive symptoms), Introvertive Anhedonia (IntAn; negative symptoms), and Impulsive Nonconformity (ImpNon; impulsive and antisocial symptoms). For the purpose of evaluating the suitability of schizotypy as an endophenotype of schizophrenia the current version of the O-LIFE was translated into German: its psychometric properties (including re-test reliability and construct validity) were examined in a large sample (n > 1200) and compared to those of the English original. The German version was both highly reliable and consistent with the original. The study aimed to show that schizotypy as measured by the O-LIFE can indeed be regarded as an endophenotype of schizophrenia in terms of genetic associations regarding relevant dopamine-related candidate polymorphisms of schizotypy [i.e., Val158Met-polymorphism of the COMT gene, uVNTR of the MAOA gene, Taq1A-polymorphism of the DRD2 gene, VNTR of the SLC6A3 (DAT) gene]. We also wanted to compare the genetic associations of the O-LIFE to those published using other operationalizations of schizotypy. Our results show a large number of significant associations and borderline-significant trends between the O-LIFE sub-scales and a range of genes, thereby supporting using the O-LIFE in the search for endophenotypic markers. PMID:23355817

Childhood Trauma and COMT Genotype Interact to Increase Hippocampal Activation in Resilient Individuals.

PubMed

van Rooij, Sanne J H; Stevens, Jennifer S; Ely, Timothy D; Fani, Negar; Smith, Alicia K; Kerley, Kimberly A; Lori, Adriana; Ressler, Kerry J; Jovanovic, Tanja

2016-01-01

Both childhood trauma and a functional catechol-O-methyltransferase (COMT) genetic polymorphism have been associated with posttraumatic stress disorder (PTSD) and depression; however, it is still unclear whether the two interact and how this interaction relates to long-term risk or resilience. Imaging and genotype data were collected on 73 highly traumatized women. DNA extracted from saliva was used to determine COMT genotype (Val/Val, n = 38, Met carriers, n = 35). Functional MRI data were collected during a Go/NoGo task to investigate the neurocircuitry underlying response inhibition. Self-report measures of adult and childhood trauma exposure, PTSD and depression symptom severity, and resilience were collected. Childhood trauma was found to interact with COMT genotype to impact inhibition-related hippocampal activation. In Met carriers, more childhood trauma was associated with decreased hippocampal activation, whereas in the Val/Val group childhood trauma was related to increased hippocampal activation. Second, hippocampal activation correlated negatively with PTSD and depression symptoms and positively with trait resilience. Moreover, hippocampal activation mediated the relationship between childhood trauma and psychiatric risk or resilience in the Val/Val, but not in the Met carrier group. These data reveal a potential mechanism by which childhood trauma and COMT genotype interact to increase risk for trauma-related psychopathology or resilience. Hippocampal recruitment during inhibition may improve the ability to use contextual information to guide behavior, thereby enhancing resilience in trauma-exposed individuals. This finding may contribute to early identification of individuals at risk and suggests a mechanism that can be targeted in future studies aiming to prevent or limit negative outcomes.

The interaction between cannabis use and the Val158Met polymorphism of the COMT gene in psychosis: A transdiagnostic meta – analysis

PubMed Central

Schäfer, Annika Theresia; Damen, Thomas; Uittenboogaard, Aniek; Krolinski, Pauline; Nwosu, Chinyere Vicky; Pinckaers, Florentina Maria Egidius; Rotee, Iris Leah Marije; Ermiş, Ayşegül; Kennedy, James L.; Nieman, Dorien H.; Tiwari, Arun; van Os, Jim

2018-01-01

Background Neither environmental nor genetic factors are sufficient to predict the transdiagnostic expression of psychosis. Therefore, analysis of gene-environment interactions may be productive. Objective A meta-analysis was performed using papers investigating the interaction between cannabis use and catechol-O-methyl transferase (COMT) polymorphism Val158Met (COMTVal158Met). Data sources PubMed, Embase, PsychInfo. Study eligibility criteria All observational studies assessing the interaction between COMTVal158Met and cannabis with any psychosis or psychotic symptoms measure as an outcome. Study appraisal and synthesis methods A meta-analysis was performed using the Meta-analysis of Observational Studies in Epidemiology guidelines and forest plots were generated. Thirteen articles met the selection criteria: 7 clinical studies using a case-only design, 3 clinical studies with a dichotomous outcome, and 3 studies analysing a continuous outcome of psychotic symptoms below the threshold of psychotic disorder. The three study types were analysed separately. Validity of the included studies was assessed using "A Cochrane Risk of Bias Assessment Tool: for Non-Randomized Studies of Interventions". Results For case-only studies, a significant interaction was found between cannabis use and COMTVal158Met, with an OR of 1.45 (95% Confidence Interval = 1.05–2.00; Met/Met as the risk genotype). However, there was no evidence for interaction in either the studies including dichotomous outcomes (B = -0.51, 95% Confidence Interval -1.72, 0.70) or the studies including continuous outcomes (B = -0.04 95% Confidence Interval -0.16–0.08). Limitation A substantial part of the included studies used the case-only design, which has lower validity and tends to overestimate true effects. Conclusion The interaction term between cannabis use and COMTVal158Met was only statistically significant in the case-only studies, but not in studies using other clinical or non-clinical psychosis outcomes. Future additional high quality studies might change current perspectives, yet currently evidence for the interaction remains unconvincing. PMID:29444152

The interaction of early life experiences with COMT val158met affects anxiety sensitivity.

PubMed

Baumann, C; Klauke, B; Weber, H; Domschke, K; Zwanzger, P; Pauli, P; Deckert, J; Reif, A

2013-11-01

The pathogenesis of anxiety disorders is considered to be multifactorial with a complex interaction of genetic factors and individual environmental factors. Therefore, the aim of this study was to examine gene-by-environment interactions of the genes coding for catechol-O-methyltransferase (COMT) and monoamine oxidase A (MAOA) with life events on measures related to anxiety. A sample of healthy subjects (N = 782; thereof 531 women; mean age M = 24.79, SD = 6.02) was genotyped for COMT rs4680 and MAOA-uVNTR (upstream variable number of tandem repeats), and was assessed for childhood adversities [Childhood Trauma Questionnaire (CTQ)], anxiety sensitivity [Anxiety Sensitivity Index (ASI)] and anxious apprehension [Penn State Worry Questionnaire (PSWQ)]. Main and interaction effects of genotype, environment and gender on measures related to anxiety were assessed by means of regression analyses. Association analysis showed no main gene effect on either questionnaire score. A significant interactive effect of childhood adversities and COMT genotype was observed: Homozygosity for the low-active met allele and high CTQ scores was associated with a significant increment of explained ASI variance [R(2) = 0.040, false discovery rate (FDR) corrected P = 0.04]. A borderline interactive effect with respect to MAOA-uVNTR was restricted to the male subgroup. Carriers of the low-active MAOA allele who reported more aversive experiences in childhood exhibited a trend for enhanced anxious apprehension (R(2) = 0.077, FDR corrected P = 0.10). Early aversive life experiences therefore might increase the vulnerability to anxiety disorders in the presence of homozygosity for the COMT 158met allele or low-active MAOA-uVNTR alleles. © 2013 John Wiley & Sons Ltd and International Behavioural and Neural Genetics Society.

Joint Effects of Smoking and Gene Variants Involved in Sex Steroid Metabolism on Hot Flashes in Late Reproductive-Age Women

PubMed Central

Freeman, Ellen W.; Sammel, Mary D.; Queen, Kaila; Lin, Hui; Rebbeck, Timothy R.

2012-01-01

Background: Although smoking has a known association with hot flashes, the factors distinguishing smokers at greatest risk for menopausal symptoms have not been well delineated. Recent evidence supports a relationship between menopausal symptoms and variants in several genes encoding enzymes that metabolize substrates such as sex steriods, xenobiotics, and catechols. It is currently not known whether the impact of smoking on hot flashes is modified by the presence of such variants. Objective: The objective of the study was to investigate the relationship between smoking and hot flash occurrence as a function of genetic variation in sex steroid-metabolizing enzymes. Methods: A cross-sectional analysis of data from the Penn Ovarian Aging study, an ongoing population-based cohort of late reproductive-aged women, was performed. Smoking behavior was characterized. Single-nucleotide polymorphisms in five genes were investigated: COMT Val158Met (rs4680), CYP1A2*1F (rs762551), CYP1B1*4 (Asn452Ser, rs1800440), CYP1B1*3 (Leu432Val, rs1056836), and CYP3A4*1B (rs2740574). Results: Compared with nonsmokers, European-American COMT Val158Met double-variant carriers who smoked had increased odds of hot flashes [adjusted odds ratio (AOR) 6.15, 95% confidence interval (CI) 1.32–28.78)]; European-American COMT Val158Met double-variant carriers who smoked heavily had more frequent moderate or severe hot flashes than nonsmokers (AOR 13.7, 95% CI 1.2–154.9). European-American CYP 1B1*3 double-variant carriers who smoked described more frequent moderate or severe hot flashes than nonsmoking (AOR 20.6, 95% CI 1.64–257.93) and never-smoking (AOR 20.59, 95% CI 1.39–304.68) carriers, respectively. African-American single-variant CYP 1A2 carriers who smoked were more likely to report hot flashes than the nonsmoking carriers (AOR 6.16, 95% CI 1.11–33.91). Conclusion: This is the first report demonstrating the effects of smoking within the strata of gene variants involved in sex steroid metabolism on hot flashes in late reproductive-age women. The identification of individuals with a genetic susceptibility to smoking-related menopausal symptoms could contribute to interventions targeted at reducing reproductive morbidity both in the menopause and across the reproductive life course. PMID:22466345

Interaction between COMT Val(158)Met polymorphism and childhood adversity affects reward processing in adulthood.

PubMed

Boecker-Schlier, Regina; Holz, Nathalie E; Buchmann, Arlette F; Blomeyer, Dorothea; Plichta, Michael M; Jennen-Steinmetz, Christine; Wolf, Isabella; Baumeister, Sarah; Treutlein, Jens; Rietschel, Marcella; Meyer-Lindenberg, Andreas; Banaschewski, Tobias; Brandeis, Daniel; Laucht, Manfred

2016-05-15

Accumulating evidence suggests that altered dopamine transmission may increase the risk of mental disorders such as ADHD, schizophrenia or depression, possibly mediated by reward system dysfunction. This study aimed to clarify the impact of the COMT Val(158)Met polymorphism in interaction with environmental variation (G×E) on neuronal activity during reward processing. 168 healthy young adults from a prospective study conducted over 25years participated in a monetary incentive delay task measured with simultaneous EEG-fMRI. DNA was genotyped for COMT, and childhood family adversity (CFA) up to age 11 was assessed by a standardized parent interview. At reward delivery, a G×E revealed that fMRI activation for win vs. no-win trials in reward-related regions increased with the level of CFA in Met homozygotes as compared to Val/Met heterozygotes and Val homozygotes, who showed no significant effect. During the anticipation of monetary vs. verbal rewards, activation decreased with the level of CFA, which was also observed for EEG, in which the CNV declined with the level of CFA. These results identify convergent genetic and environmental effects on reward processing in a prospective study. Moreover, G×E effects during reward delivery suggest that stress during childhood is associated with higher reward sensitivity and reduced efficiency in processing rewarding stimuli in genetically at-risk individuals. Together with previous evidence, these results begin to define a specific system mediating interacting effects of early environmental and genetic risk factors, which may be targeted by early intervention and prevention. Copyright © 2016 Elsevier Inc. All rights reserved.

Effects of human blood levels of two PAH mixtures on the AHR signalling activation pathway and CYP1A1 and COMT target genes in granulosa non-tumor and granulosa tumor cell lines.

PubMed

Zajda, Karolina; Ptak, Anna; Rak, Agnieszka; Fiedor, Elżbieta; Grochowalski, Adam; Milewicz, Tomasz; Gregoraszczuk, Ewa L

2017-08-15

Epidemiological studies have shown a link between problems with offspring of couples living in a contaminated environment in comparison to those who live in an uncontaminated environment. We measured the concentrations of 16 priority polycyclic aromatic hydrocarbons (PAHs) in maternal and cord blood. To explore the mechanism of the effects of PAH mixtures on nonluteinized granulosa cells (HGrC1) and granulosa tumor cells (COV434), as well as cell proliferation and apoptosis, we investigated the effect of PAH mixtures on the expression of the aryl hydrocarbon receptor (AHR), aryl hydrocarbon receptor nuclear translocator (ARNT) and aryl hydrocarbon receptor repressor (AHRR) genes, as well as the expression and activity of target genes cytochrome P450 1A1 (CYP1A1) and catechol-O-methyltransferase (COMT). The cells were exposed to mixture 1 (M1), composed of all 16 priority PAHs, and mixture 2 (M2), composed of five PAHs which are not classified as human carcinogens, and which are observed in the highest amounts both in maternal and cord blood. All 16 priority PAHs were bioavailable in maternal and cord plasma, suggesting that perinatal exposure should be considered. In HGrC1 cells, M1 increased AHR and ARNT, but decreased AHRR expression, in parallel with increased CYP1A1 and COMT expression and activity. M2 decreased AHR and AHRR, and increased ARNT, with no effect on CYP1A1 expression and activity; however, it did increase COMT expression and activity. In tumor cells, M1 lowered AHR and up-regulated AHRR and ARNT expression, consequently decreasing CYP1A1 expression and COMT activity. M2 up-regulated AHR and ARNT, down-regulated AHRR, and had no effect on CYP1A1 and COMT expression, but decreased COMT activity. We hypothesise that, dependent on composition, mixtures of PAHs activate the AHR differently through varying transcription responses: in HGrC1, a canonical AHR mechanism of M1, with activation of CYP1A1 important for detoxication, while in COV434, a noncanonical AHR mechanism, probably by activation the nuclear factor NFkB. Copyright © 2017. Published by Elsevier B.V.

A Transposon in Comt Generates mRNA Variants and Causes Widespread Expression and Behavioral Differences among Mice

PubMed Central

Wang, Xusheng; Miles, Michael F.; Lu, Lu; Williams, Robert W.

2010-01-01

Background Catechol-O-methyltransferase (COMT) is a key enzyme responsible for the degradation of dopamine and norepinephrine. COMT activity influences cognitive and emotional states in humans and aggression and drug responses in mice. This study identifies the key sequence variant that leads to differences in Comt mRNA and protein levels among mice, and that modulates synaptic function and pharmacological and behavioral traits. Methodology/Principal Findings We examined Comt expression in multiple tissues in over 100 diverse strains and several genetic crosses. Differences in expression map back to Comt and are generated by a 230 nt insertion of a B2 short interspersed element (B2 SINE) in the proximal 3′ UTR of Comt in C57BL/6J. This transposon introduces a premature polyadenylation signal and creates a short 3′ UTR isoform. The B2 SINE is shared by a subset of strains, including C57BL/6J, A/J, BALB/cByJ, and AKR/J, but is absent in others, including DBA/2J, FVB/NJ, SJL/J, and wild subspecies. The short isoform is associated with increased protein expression in prefrontal cortex and hippocampus relative to the longer ancestral isoform. The Comt variant causes downstream differences in the expression of genes involved in synaptic function, and also modulates phenotypes such as dopamine D1 and D2 receptor binding and pharmacological responses to haloperidol. Conclusions/Significance We have precisely defined the B2 SINE as the source of variation in Comt and demonstrated that a transposon in a 3′ UTR can alter mRNA isoform use and modulate behavior. The recent fixation of the variant in a subset of strains may have contributed to the rapid divergence of inbred strains. PMID:20808911

Functional characterization of cinnamyl alcohol dehydrogenase and caffeic acid O-methyltransferase in Brachypodium distachyon

PubMed Central

2013-01-01

Background Lignin is a significant barrier in the conversion of plant biomass to bioethanol. Cinnamyl alcohol dehydrogenase (CAD) and caffeic acid O-methyltransferase (COMT) catalyze key steps in the pathway of lignin monomer biosynthesis. Brown midrib mutants in Zea mays and Sorghum bicolor with impaired CAD or COMT activity have attracted considerable agronomic interest for their altered lignin composition and improved digestibility. Here, we identified and functionally characterized candidate genes encoding CAD and COMT enzymes in the grass model species Brachypodium distachyon with the aim of improving crops for efficient biofuel production. Results We developed transgenic plants overexpressing artificial microRNA designed to silence BdCAD1 or BdCOMT4. Both transgenes caused altered flowering time and increased stem count and weight. Downregulation of BdCAD1 caused a leaf brown midrib phenotype, the first time this phenotype has been observed in a C3 plant. While acetyl bromide soluble lignin measurements were equivalent in BdCAD1 downregulated and control plants, histochemical staining and thioacidolysis indicated a decrease in lignin syringyl units and reduced syringyl/guaiacyl ratio in the transgenic plants. BdCOMT4 downregulated plants exhibited a reduction in total lignin content and decreased Maule staining of syringyl units in stem. Ethanol yield by microbial fermentation was enhanced in amiR-cad1-8 plants. Conclusion These results have elucidated two key genes in the lignin biosynthetic pathway in B. distachyon that, when perturbed, may result in greater stem biomass yield and bioconversion efficiency. PMID:23902793

Potential Genetic Risk Factors for Chronic TMD: Genetic Associations from the OPPERA Case Control Study

PubMed Central

Smith, Shad B.; Maixner, Dylan; Greenspan, Joel; Dubner, Ron; Fillingim, Roger; Ohrbach, Richard; Knott, Charles; Slade, Gary; Bair, Eric; Gibson, Dustin G.; Zaykin, Dmitri V.; Weir, Bruce; Maixner, William; Diatchenko, Luda

2011-01-01

Genetic factors play a role in the etiology of persistent pain conditions, putatively by modulating underlying processes such as nociceptive sensitivity, psychological well-being, inflammation, and autonomic response. However, to date, only a few genes have been associated with temporomandibular disorders (TMD). This study evaluated 358 genes involved in pain processes, comparing allelic frequencies between 166 cases with chronic TMD and 1442 controls enrolled in the OPPERA (Orofacial Pain: Prospective Evaluation and Risk Assessment) study cooperative agreement. To enhance statistical power, 182 TMD cases and 170 controls from a similar study were included in the analysis. Genotyping was performed using the Pain Research Panel, an Affymetrix gene chip representing 3295 single nucleotide polymorphisms, including ancestry-informative markers that were used to adjust for population stratification. Adjusted associations between genetic markers and TMD case status were evaluated using logistic regression. The OPPERA findings provided evidence supporting previously-reported associations between TMD and two genes: HTR2A and COMT. Other genes were revealed as potential new genetic risk factors for TMD, including NR3C1, CAMK4, CHRM2, IFRD1, and GRK5. While these findings need to be replicated in independent cohorts, the genes potentially represent important markers of risk for TMD and they identify potential targets for therapeutic intervention. PMID:22074755

COMT-by-Sex Interaction Effect on Psychosis Proneness

PubMed Central

de Castro-Catala, Marta; Barrantes-Vidal, Neus; Sheinbaum, Tamara; Moreno-Fortuny, Artal; Kwapil, Thomas R.; Rosa, Araceli

2015-01-01

Schizotypy phenotypes in the general population share etiopathogenic mechanisms and risk factors with schizophrenia, supporting the notion of psychosis as a continuum ranging from nonclinical to clinical deviance. Catechol-O-methyltransferase (COMT) is a candidate susceptibility gene for schizophrenia that is involved in the regulation of dopamine in the prefrontal cortex. Several recent studies have reported a sex difference in the impact of COMT genotype on psychiatric and cognitive phenotypes and personality traits. The present study investigated the association of COMT Val158Met (rs4680) with psychometric positive and negative schizotypy and psychotic experiences in a sample of 808 nonclinical young adults. The main finding was that sex moderates the association of COMT genotype with the negative dimension of both schizotypy and psychotic experiences. Male subjects carrying the Val allele tended to score higher on the negative dimension of both trait and symptom-like measures. The results from the present study are consistent with recent work suggesting an association between negative schizotypy and diminished prefrontal dopamine availability. They support the idea that a biological differentiation underlies the positive and negative schizotypy dimensions. Additionally, these findings contribute to the growing literature on sex-specific effects of COMT on the predisposition to psychiatric disorders and personality traits. PMID:25722988

Modification of menopausal hormone therapy-associated colorectal cancer risk by polymorphisms in sex steroid signaling, metabolism and transport related genes.

PubMed

Rudolph, Anja; Sainz, Juan; Hein, Rebecca; Hoffmeister, Michael; Frank, Bernd; Försti, Asta; Brenner, Hermann; Hemminki, Kari; Chang-Claude, Jenny

2011-06-01

The mechanisms underlying the association of menopausal hormone therapy (MHT) with reduced colorectal cancer (CRC) risk are unknown and the identification of genetic modifiers may yield further insight. We explored the effect modification of MHT-associated CRC risk in postmenopausal women by 47 polymorphisms with known or putative functional relevance in 16 candidate genes related to hormone metabolism (COMT, CYP1A1, CYP1A2, CYP1B1, CYP2C9, CYP2C19, CYP3A4, CYP17A1, GSTP, and HSD17B1), transport (ABCB1), and signaling (ESR1, ESR2, SHBG, PGR, and NR1I2). A total of 685 CRC patients and 684 healthy controls from a German population-based case-control study (DACHS) were genotyped. Multiplicative statistical interaction between polymorphisms and ever MHT use as well as duration of use was assessed using multivariate logistic regression. CRC risk associated with ever MHT use as well as with duration was significantly modified by rs1202168 in the transporter gene ABCB1 (P interaction=0.04). The MHT-associated risk reduction was not significant in homozygous non-carriers (odds ratio (OR) ever use=0.84, 95% confidence interval (CI) 0.53-1.34; OR per 5 year duration=0.94, 95% CI 0.83-1.08), while homozygous carriers of the minor T allele had a 57% lower risk with ever use of MHT (95% CI 0.21-0.88) and a 22% lower risk per 5 years of MHT use (95% CI 0.62-0.97). Significant effect modification was also observed for the ESR1_rs910416 polymorphism (P interaction=0.03 for ever use and 0.07 for duration of use), whereby the decreased risk was attenuated in homozygous carriers of the minor C allele (OR ever use=0.87, 95% CI 0.48-1.60, OR per 5 year duration=0.99, 95% CI 0.83-1.18). Results of this exploratory study provide first evidence that polymorphisms in genes related to estrogen transport and signaling may modify MHT-associated CRC risk but warrant replication in an independent population.

Phenolic compounds in ectomycorrhizal interaction of lignin modified silver birch

PubMed Central

Sutela, Suvi; Niemi, Karoliina; Edesi, Jaanika; Laakso, Tapio; Saranpää, Pekka; Vuosku, Jaana; Mäkelä, Riina; Tiimonen, Heidi; Chiang, Vincent L; Koskimäki, Janne; Suorsa, Marja; Julkunen-Tiitto, Riitta; Häggman, Hely

2009-01-01

Background The monolignol biosynthetic pathway interconnects with the biosynthesis of other secondary phenolic metabolites, such as cinnamic acid derivatives, flavonoids and condensed tannins. The objective of this study is to evaluate whether genetic modification of the monolignol pathway in silver birch (Betula pendula Roth.) would alter the metabolism of these phenolic compounds and how such alterations, if exist, would affect the ectomycorrhizal symbiosis. Results Silver birch lines expressing quaking aspen (Populus tremuloides L.) caffeate/5-hydroxyferulate O-methyltransferase (PtCOMT) under the 35S cauliflower mosaic virus (CaMV) promoter showed a reduction in the relative expression of a putative silver birch COMT (BpCOMT) gene and, consequently, a decrease in the lignin syringyl/guaiacyl composition ratio. Alterations were also detected in concentrations of certain phenolic compounds. All PtCOMT silver birch lines produced normal ectomycorrhizas with the ectomycorrhizal fungus Paxillus involutus (Batsch: Fr.), and the formation of symbiosis enhanced the growth of the transgenic plants. Conclusion The down-regulation of BpCOMT in the 35S-PtCOMT lines caused a reduction in the syringyl/guaiacyl ratio of lignin, but no significant effect was seen in the composition or quantity of phenolic compounds that would have been caused by the expression of PtCOMT under the 35S or UbB1 promoter. Moreover, the detected alterations in the composition of lignin and secondary phenolic compounds had no effect on the interaction between silver birch and P. involutus. PMID:19788757

Effects of COMT, DRD2, BDNF, and APOE Genotypic Variation on Treatment Efficacy and Cognitive Side Effects of Electroconvulsive Therapy.

PubMed

Bousman, Chad A; Katalinic, Natalie; Martin, Donel M; Smith, Deidre J; Ingram, Anna; Dowling, Nathan; Ng, Chee; Loo, Colleen K

2015-06-01

The aim of this study was to explore the main and interaction effects of the COMT Val158Met, DRD2 C957T, BDNF Val66Met, and APOE polymorphisms on treatment efficacy and cognitive side effects of electroconvulsive therapy (ECT). A total of 117 adult inpatients with a diagnosis of major depressive disorder recruited from 3 hospitals were administered the Montgomery-Äsberg Depression Rating Scale and a cognitive battery assessing global cognition, anterograde memory, executive function, speed and concentration, as well as retrograde memory at baseline and after ECT treatment. DRD2 C957T heterozygotes had 3.7 (95% confidence interval, 1.13-12.25; P = 0.032) greater odds of remission compared with CC homozygotes. Among the men, COMT Val/Val carriers had greater depressive symptom reduction compared with Met/Met carriers (Montgomery-Äsberg Depression Rating Scale percentage of reduction, 76% vs 35%; P = 0.020) but not among the women (P = 0.903) after ECT. For cognitive outcomes, an interaction effect on anterograde memory was observed between the DRD2 and BDNF polymorphisms (P = 0.016), in which carriers of the DRD2 TT and BDNF Val/Val genotypes had significantly less decline in anterograde performance than those that carried the TC and Met-allele (P = 0.001) or CC and Met-allele (P = 0.003) genotypes. However, no results withstood correction for multiple comparisons. These observations provide preliminary evidence supporting an association between common functional genotypic variation and ECT efficacy as well as anterograde memory side effects after ECT. Validation of these findings is required before firm conclusions can be made and clinical utility can be assessed.

Genotype status of the dopamine-related catechol-O-methyltransferase (COMT) gene corresponds with desirability of “unhealthy” foods

PubMed Central

Wallace, Deanna L.; Aarts, Esther; Uquillas, Federico d’Oleire; Dang, Linh C.; Greer, Stephanie M.; Jagust, William J.; D’Esposito, Mark

2015-01-01

The role of dopamine is extensively documented in weight regulation and food intake in both animal models and humans. Yet the role of dopamine has not been well studied in individual differences for food desirability. Genotype status of the dopamine-related catechol-O-methyltransferase (COMT) gene has been shown to influence dopamine levels, with greater COMT enzymatic activity in val/val individuals corresponding to greater degradation of dopamine. Decreased dopamine has been associated with poorer cognitive control and diminished goal-directed behavior in various behavioral paradigms. Additionally, dopaminergic-rich regions such as the frontal cortex and dorsal striatum have been shown to be important for supporting food-related decision-making. However, the role of dopamine, as assessed by COMT genotype status, in food desirability has not been fully explored. Therefore, we utilized an individual’s COMT genotype status (n=61) and investigated food desirability based on self-rated “healthy” and “unhealthy” food perceptions. Here we found val/val individuals (n=19) have greater desirability for self-rated “unhealthy” food items, but not self-rated “healthy” food items, as compared to val/met (n=24) and met/met (n=18) individuals (p<0.005). Utilizing an objective health measure for the food items, we also found val/val and val/met individuals have greater desirability for objectively defined “unhealthy” food items, as compared to met/met individuals (p<0.01). This work further substantiates a role of dopamine in food-related behaviors and more specifically in relationship to food desirability for “unhealthy” food items. PMID:25963102

Systematic review and meta-analysis of genetic risk factors for neuropathic pain.

PubMed

Veluchamy, Abirami; Hébert, Harry L; Meng, Weihua; Palmer, Colin N A; Smith, Blair H

2018-05-01

Neuropathic pain (NP) is an increasingly common chronic pain state and a major health burden, affecting approximately 7% to 10% of the general population. Emerging evidence suggests that genetic factors could partially explain individual susceptibility to NP and the estimated heritability in twins is 37%. The aim of this study was to systematically review and summarize the studies in humans that have investigated the influence of genetic factors associated with NP. We conducted a comprehensive literature search and performed meta-analyses of all the potential genetic variants associated with NP. We reviewed 29 full-text articles and identified 28 genes that were significantly associated with NP, mainly involved in neurotransmission, immune response, and metabolism. Genetic variants in HLA genes, COMT, OPRM1, TNFA, IL6, and GCH1, were found to have an association with NP in more than one study. In the meta-analysis, polymorphisms in HLA-DRB1*13 (odds ratio [OR], 2.96; confidence interval [CI], 1.93-4.56), HLA-DRB1*04 (OR, 1.40; CI, 1.02-1.93), HLA-DQB1*03 (OR, 2.86; CI, 1.57-5.21), HLA-A*33 (OR, 2.32; CI, 1.42-3.80), and HLA-B*44 (OR, 3.17; CI, 2.22-4.55) were associated with significantly increased risk of developing NP, whereas HLA-A*02 (OR, 0.64; CI, 0.47-0.87) conferred reduced risk and neither rs1799971 in OPRM1 (OR, 0.55; CI, 0.27-1.11) nor rs4680 in COMT (OR, 0.95; CI, 0.81-1.13) were significantly associated with NP. These findings demonstrate an important and specific contribution of genetic factors to the risk of developing NP. However, large-scale replication studies are required to validate these candidate genes. Our review also highlights the need for genome-wide association studies with consistent case definition to elucidate the genetic architecture underpinning NP.

A potyvirus-based gene vector allows producing active human S-COMT and animal GFP, but not human sorcin, in vector-infected plants.

PubMed

Kelloniemi, Jani; Mäkinen, Kristiina; Valkonen, Jari P T

2006-05-01

Potato virus A (PVA), a potyvirus with a (+)ssRNA genome translated to a large polyprotein, was engineered and used as a gene vector for expression of heterologous proteins in plants. Foreign genes including jellyfish GFP (Aequorea victoria) encoding the green fluorescent protein (GFP, 27 kDa) and the genes of human origin (Homo sapiens) encoding a soluble resistance-related calcium-binding protein (sorcin, 22 kDa) and the catechol-O-methyltransferase (S-COMT; 25 kDa) were cloned between the cistrons for the viral replicase and coat protein (CP). The inserts caused no adverse effects on viral infectivity and virulence, and the inserted sequences remained intact in progeny viruses in the systemically infected leaves. The heterologous proteins were released from the viral polyprotein following cleavage by the main viral proteinase, NIa, at engineered proteolytic processing sites flanking the insert. Active GFP, as indicated by green fluorescence, and S-COMT with high levels of enzymatic activity were produced. In contrast, no sorcin was detected despite the expected equimolar amounts of the foreign and viral proteins being expressed as a polyprotein. These data reveal inherent differences between heterologous proteins in their suitability for production in plants.

Interaction of childhood urbanicity and variation in dopamine genes alters adult prefrontal function as measured by functional magnetic resonance imaging (fMRI).

PubMed

Reed, Jessica L; D'Ambrosio, Enrico; Marenco, Stefano; Ursini, Gianluca; Zheutlin, Amanda B; Blasi, Giuseppe; Spencer, Barbara E; Romano, Raffaella; Hochheiser, Jesse; Reifman, Ann; Sturm, Justin; Berman, Karen F; Bertolino, Alessandro; Weinberger, Daniel R; Callicott, Joseph H

2018-01-01

Brain phenotypes showing environmental influence may help clarify unexplained associations between urban exposure and psychiatric risk. Heritable prefrontal fMRI activation during working memory (WM) is such a phenotype. We hypothesized that urban upbringing (childhood urbanicity) would alter this phenotype and interact with dopamine genes that regulate prefrontal function during WM. Further, dopamine has been hypothesized to mediate urban-associated factors like social stress. WM-related prefrontal function was tested for main effects of urbanicity, main effects of three dopamine genes-catechol-O-methyltransferase (COMT), dopamine receptor D1 (DRD1), and dopamine receptor D2 (DRD2)-and, importantly, dopamine gene-by-urbanicity interactions. For COMT, three independent human samples were recruited (total n = 487). We also studied 253 subjects genotyped for DRD1 and DRD2. 3T fMRI activation during the N-back WM task was the dependent variable, while childhood urbanicity, dopamine genotype, and urbanicity-dopamine interactions were independent variables. Main effects of dopamine genes and of urbanicity were found. Individuals raised in an urban environment showed altered prefrontal activation relative to those raised in rural or town settings. For each gene, dopamine genotype-by-urbanicity interactions were shown in prefrontal cortex-COMT replicated twice in two independent samples. An urban childhood upbringing altered prefrontal function and interacted with each gene to alter genotype-phenotype relationships. Gene-environment interactions between multiple dopamine genes and urban upbringing suggest that neural effects of developmental environmental exposure could mediate, at least partially, increased risk for psychiatric illness in urban environments via dopamine genes expressed into adulthood.

MAOA Influences the Trajectory of Attentional Development

PubMed Central

Lundwall, Rebecca A.; Rasmussen, Claudia G.

2016-01-01

Attention is vital to success in all aspects of life (Meck and Benson, 2002; Erickson et al., 2015), hence it is important to identify biomarkers of later attentional problems early enough to intervene. Our objective was to determine if any of 11 genes (APOE, BDNF, HTR4, CHRNA4, COMT, DRD4, IGF2, MAOA, SLC5A7, SLC6A3, and SNAP25) predicted the trajectory of attentional development within the same group of children between infancy and childhood. We recruited follow up participants from children who participated as infants in visual attention studies and used a similar task at both time points. Using multilevel modeling, we associated changes in the participant’s position in the distribution of scores in infancy to his/her position in childhood with genetic markers on each of 11 genes. While all 11 genes predicted reaction time (RT) residual scores, only Monoamine oxidase A (MAOA) had a significant interaction including time point. We conclude that the MAOA single nucleotide polymorphism (SNP) rs1137070 is useful in predicting which girls are likely to develop slower RTs on an attention task between infancy and childhood. This early identification is likely to be helpful in early intervention. PMID:27610078

Smoking, genes encoding dopamine pathway and risk for Parkinson's disease.

PubMed

Gu, Zhuqin; Feng, Xiuli; Dong, Xiumin; Chan, Piu

2010-09-20

Smoking has been reported to be inversely associated with Parkinson's disease (PD) in many studies, but a recent study in China found that smoking increased the risk of PD. Variants in genes associated with dopamine metabolism found to increase the risk for PD have also been associated with smoking behavior. To investigate the association between smoking and PD in a Chinese population and determine whether the genetic variants of genes involved in dopamine metabolism influence the relationship between smoking and risk for PD. Chinese PD patients were recruited from Xuanwu Hospital. Controls were sampled from community. Detailed information on life-long smoking behavior was collected by face-to-face interview. Genotypes were determined for SLC6A3 VNTR, COMT Val108/158Met and MAO-B intron13 A/G polymorphisms by PCR-RFLP, DHPLC and sequencing. Chi-square and logistic regression model were used in the analysis. 176 PD cases and 354 controls were enrolled in this study. 23.9% cases are smokers, compared to 48.0% in controls. Ever smoking is inversely associated with PD (odds ratio=0.14, 95% CI 0.08-0.26, adjusted for age and gender). None of the above-mentioned genetic polymorphisms was associated with PD risk or smoking. When each variant was included in the logistic regression model, the inverse association between smoking and PD remained the same, and the interactions between smoking and variants were not significant in the model. Our data support a reduction of PD risk associated with smoking in a Chinese population. These variants of genes associated with DA uptake and metabolism do not affect the inverse association between smoking and PD. Copyright 2010 Elsevier Ireland Ltd. All rights reserved.

COMT and DRD2/ANKK-1 gene-gene interaction account for resetting of gamma neural oscillations to auditory stimulus-driven attention.

PubMed

Garcia-Garcia, Manuel; Via, Marc; Zarnowiec, Katarzyna; SanMiguel, Iria; Escera, Carles; Clemente, Immaculada C

2017-01-01

Attention capture by potentially relevant environmental stimuli is critical for human survival, yet it varies considerably among individuals. A large series of studies has suggested that attention capture may depend on the cognitive balance between maintenance and manipulation of mental representations and the flexible switch between goal-directed representations and potentially relevant stimuli outside the focus of attention; a balance that seems modulated by a prefrontostriatal dopamine pathway. Here, we examined inter-individual differences in the cognitive control of attention through studying the effects of two single nucleotide polymorphisms regulating dopamine at the prefrontal cortex and the striatum (i.e., COMTMet108/158Val and ANKK1/DRD2TaqIA) on stimulus-driven attention capture. Healthy adult participants (N = 40) were assigned to different groups according to the combination of the polymorphisms COMTMet108/158Val and ANKK1/DRD2TaqIA, and were instructed to perform on a well-established distraction protocol. Performance in individuals with a balance between prefrontal dopamine display and striatal receptor density was slowed down by the occurrence of unexpected distracting events, while those with a rather unbalanced dopamine activity were able maintain task performance with no time delay, yet at the expense of a slightly lower accuracy. This advantage, associated to their distinct genetic profiles, was paralleled by an electrophysiological mechanism of phase-resetting of gamma neural oscillation to the novel, distracting events. Taken together, the current results suggest that the epistatic interaction between COMTVal108/158Met and ANKK1/DRD2 TaqIa genetic polymorphisms lies at the basis of stimulus-driven attention capture.

Genetic polymorphisms in phase I and phase II enzymes and breast cancer risk associated with menopausal hormone therapy in postmenopausal women.

PubMed

2010-01-01

Recent findings indicate a greater risk of postmenopausal breast cancer with estrogen-progestagen therapy than estrogen monotherapy, and more so for current than past use. Few studies have examined individual genetic susceptibility to the effects of menopausal hormone therapy. We used two population-based case-control studies with 3,155 postmenopausal breast cancer patients and 5,496 controls to evaluate modification of breast cancer risk associated with duration of hormone use by genes involved in hormone metabolism and detoxification. Twenty-eight polymorphisms in eight genes of phase I (CYP1A1, CYP1A2, CYP1B1, CYP2C9, CYP2C19, CYP3A4, CYP3A5, CYP3A7) and nine genes of phase II enzymes (COMT, GSTM1, GSTM3, GSTP1, GSTT1, SULT1A1, UGT1A1, UGT1A6, UGT2B7) were genotyped. The risk associated with duration of use of combined estrogen-progestagen therapy was significantly modified by genetic polymorphisms located in CYP1B1, GSTP1, and GSTT1. In homozygote carriers of the CYP1B1_142_G and the CYP1B1_355 _T variant alleles, adjusted odds ratios (OR) per year of use were 1.06 (95% confidence interval (CI) = 1.02-1.09) and 1.06 (95% CI = 1.03-1.09), respectively, compared with 1.02 (95% CI = 1.01-1.03) in non-carriers of either polymorphism (p(interaction) = 0.01). Carriers of the functional GSTT1 allele and the GSTP1_341_T allele were at significantly higher risks associated with hormone use compared with non-carriers (p(interaction) = 0.0001 and 0.02). CYP1A1_2452_C>A significantly reduced the risk associated with duration of use of estrogen monotherapy (p(interaction) = 0.01). The finding regarding GSTT1 was still statistically significant after corrections for multiple comparisons. Postmenopausal breast cancer risk associated with hormone therapy may be modified by genetically determined variations in phase I and II enzymes involved in steroid hormone metabolism.

Serotonin and Dopamine Gene Variation and Theory of Mind Decoding Accuracy in Major Depression: A Preliminary Investigation.

PubMed

Zahavi, Arielle Y; Sabbagh, Mark A; Washburn, Dustin; Mazurka, Raegan; Bagby, R Michael; Strauss, John; Kennedy, James L; Ravindran, Arun; Harkness, Kate L

2016-01-01

Theory of mind-the ability to decode and reason about others' mental states-is a universal human skill and forms the basis of social cognition. Theory of mind accuracy is impaired in clinical conditions evidencing social impairment, including major depressive disorder. The current study is a preliminary investigation of the association of polymorphisms of the serotonin transporter (SLC6A4), dopamine transporter (DAT1), dopamine receptor D4 (DRD4), and catechol-O-methyl transferase (COMT) genes with theory of mind decoding in a sample of adults with major depression. Ninety-six young adults (38 depressed, 58 non-depressed) completed the 'Reading the Mind in the Eyes task' and a non-mentalistic control task. Genetic associations were only found for the depressed group. Specifically, superior accuracy in decoding mental states of a positive valence was seen in those homozygous for the long allele of the serotonin transporter gene, 9-allele carriers of DAT1, and long-allele carriers of DRD4. In contrast, superior accuracy in decoding mental states of a negative valence was seen in short-allele carriers of the serotonin transporter gene and 10/10 homozygotes of DAT1. Results are discussed in terms of their implications for integrating social cognitive and neurobiological models of etiology in major depression.

Consolidated bioprocessing of transgenic switchgrass by an engineered and evolved Clostridium thermocellum strain

DOE Office of Scientific and Technical Information (OSTI.GOV)

Yee, Kelsey L; Rodriguez Jr, Miguel; Thompson, Olivia A

Background: Switchgrass is an abundant and dedicated bioenergy feedstock however its inherent recalcitrance is one of the economic hurdles for producing biofuels. The down-regulation of the caffeic acid O-methyl transferase (COMT) gene in the lignin pathway of switchgrass reduced lignin content and S/G ratio, and the transgenic lines showed improved fermentation yield with S. cerevisiae and C. thermocellum (ATCC 27405) in comparison to the wild-type switchgrass. Results: Here we examine the fermentation potential of the COMT transgenic switchgrass and its wild-type line, with an engineered and evolved Clostridium thermocellum (M1570) strain. The fermentation of the transgenic switchgrass had superior conversionmore » relative to the control line with an increase of 20% and ethanol was the primary metabolite accounting for 90% of the total metabolites measured by HPLC. Conclusions: The down-regulation of the COMT gene in switchgrass reduced recalcitrance and improved microbial bioconversion yield. Moreover, these results showed ethanol as the main fermentation metabolite produced by an engineered and evolved C. thermocellum strain grown on a transgenic switchgrass.« less

Stress-related methylation of the catechol-O-methyltransferase Val 158 allele predicts human prefrontal cognition and activity.

PubMed

Ursini, Gianluca; Bollati, Valentina; Fazio, Leonardo; Porcelli, Annamaria; Iacovelli, Luisa; Catalani, Assia; Sinibaldi, Lorenzo; Gelao, Barbara; Romano, Raffaella; Rampino, Antonio; Taurisano, Paolo; Mancini, Marina; Di Giorgio, Annabella; Popolizio, Teresa; Baccarelli, Andrea; De Blasi, Antonio; Blasi, Giuseppe; Bertolino, Alessandro

2011-05-04

DNA methylation at CpG dinucleotides is associated with gene silencing, stress, and memory. The catechol-O-methyltransferase (COMT) Val(158) allele in rs4680 is associated with differential enzyme activity, stress responsivity, and prefrontal activity during working memory (WM), and it creates a CpG dinucleotide. We report that methylation of the Val(158) allele measured from peripheral blood mononuclear cells (PBMCs) of Val/Val humans is associated negatively with lifetime stress and positively with WM performance; it interacts with stress to modulate prefrontal activity during WM, such that greater stress and lower methylation are related to reduced cortical efficiency; and it is inversely related to mRNA expression and protein levels, potentially explaining the in vivo effects. Finally, methylation of COMT in prefrontal cortex and that in PBMCs of rats are correlated. The relationship of methylation of the COMT Val(158) allele with stress, gene expression, WM performance, and related brain activity suggests that stress-related methylation is associated with silencing of the gene, which partially compensates the physiological role of the high-activity Val allele in prefrontal cognition and activity. Moreover, these results demonstrate how stress-related DNA methylation of specific functional alleles impacts directly on human brain physiology beyond sequence variation.

Genetic moderation of the association between regulatory focus and reward responsiveness: a proof-of-concept study.

PubMed

Goetz, Elena L; Hariri, Ahmad R; Pizzagalli, Diego A; Strauman, Timothy J

2013-02-01

Recent studies implicate individual differences in regulatory focus as contributing to self-regulatory dysfunction, particularly not responding to positive outcomes. How such individual differences emerge, however, is unclear. We conducted a proof-of-concept study to examine the moderating effects of genetically driven variation in dopamine signaling, a key modulator of neural reward circuits, on the association between regulatory focus and reward cue responsiveness. Healthy Caucasians (N=59) completed a measure of chronic regulatory focus and a probabilistic reward task. A common functional genetic polymorphism impacting prefrontal dopamine signaling (COMT rs4680) was evaluated. Response bias, the participants' propensity to modulate behavior as a function of reward, was predicted by an interaction of regulatory focus and COMT genotype. Specifically, self-perceived success at achieving promotion goals predicted total response bias, but only for individuals with the COMT genotype (Val/Val) associated with relatively increased phasic dopamine signaling and cognitive flexibility. The combination of success in promotion goal pursuit and Val/Val genotype appears to facilitate responding to reward opportunities in the environment. This study is among the first to integrate an assessment of self-regulatory style with an examination of genetic variability that underlies responsiveness to positive outcomes in goal pursuit.

evaluation of the bioconversion of genetically modified switchgrass using simultaneous saccharification and fermentation ans a consolidated bioprocessing approach

DOE Office of Scientific and Technical Information (OSTI.GOV)

Yee, Kelsey L; Rodriguez, Jr., Miguel; Tschaplinski, Timothy J

2012-01-01

Abstract Background: The inherent recalcitrance of lignocellulosic biomass is one of the major economic hurdles for the production of fuels and chemicals from biomass. Additionally, lignin is recognized as having a negative impact on enzymatic hydrolysis of biomass, and as a result much interest has been placed on modifying the lignin pathway to improve bioconversion of lignocellulosic feedstocks. Results: Previous results showed down-regulation of the caffeic acid 3-O-methyl transferase (COMT) gene in the lignin pathway yielded switchgrass (Panicum virgatum) that was more susceptible to bioconversion after dilute acid pretreatment. Here we examined the response of these plant lines to mildermore » pretreatment conditions with yeast-based SSF, CBP with Clostridium thermocellum, and fermentations with the cellulolytic extreme thermophiles, Caldicellulosiruptor bescii and Caldicellulosiruptor obsidiansis. Unlike the S. cerevisiae SSF conversions, fermentations of pretreated down-regulated COMT transgenic switchgrass with C. thermocellum showed an apparent inhibition of fermentation not observed in the wild-type switchgrass. This inhibition can be eliminated by hot water extraction of the pretreated biomass which resulted in superior conversion yield with transgenic versus wild-type switchgrass for C. thermocellum, also exceeding the yeast-based SSF yield. Further fermentation evaluation of the transgenic switchgrass indicated differential inhibition for the Caldicellulosiruptor strains, which could not be rectified by additional processing conditions. Gas chromatography-mass spectrometry metabolite profiling was used to examine the fermentation broth to elucidate the relative abundance of lignin derived aromatic compounds. The types and abundance of fermentation-derived lignin constituents varied between C. thermocellum and each of the Caldicellulosiruptor strains. Conclusions: The down-regulation of the COMT gene improves the bioconversion of switchgrass relative to the wild-type regardless of the pretreatment condition or fermentation microorganism. However, bacterial fermentations demonstrated strain-dependent sensitivity to the COMT transgenic biomass, likely due to additional soluble lignin pathway-derived constituents resulting from the COMT gene disruption. Removal of these inhibitory constituents permitted completion of fermentation by C. thermocellum, but not by the Caldicellulosiruptor strains. The reason for this difference needs to be explored further.« less

Identification and characterization of a catechol-o-methyltransferase cDNA in the catfish Heteropneustes fossilis: Tissue, sex and seasonal variations, and effects of gonadotropin and 2-hydroxyestradiol-17β on mRNA expression.

PubMed

Chaube, R; Rawat, A; Inbaraj, R M; Bobe, J; Guiguen, Y; Fostier, A; Joy, K P

2017-05-15

Catechol-O-methyltransferase (COMT) is involved in the methylation and inactivation of endogenous and xenobiotic catechol compounds, and serves as a common biochemical link in the catecholamine and catecholestrogen metabolism. Studies on cloning, sequencing and function characterization comt gene in lower vertebrates like fish are fewer. In the present study, a full-length comt cDNA of 1442bp with an open-reading frame (ORF) of 792bp, and start codon (ATG) at nucleotide 162 and stop codon (TAG) at nucleotide 953 was isolated and characterized in the stinging catfish Heteropneustes fossilis (accession No. KT597925). The ORF codes for a protein of 263 amino acid residues, which is also validated by the catfish transcriptome data analysis. The catfish Comt shared conserved putative structural regions important for S-adenosyl methionine (AdoMet)- and catechol-binding, transmembrane regions, two glycosylation sites (N-65 and N-91) at the N-terminus and two phosphorylation sites (Ser-235 and Thr-240) at the C-terminus. The gene was expressed in all tissues examined and the expression showed significant sex dimorphic distribution with high levels in females. The transcript was abundant in the liver, brain and gonads and low in muscles. The transcripts showed significant seasonal variations in the brain and ovary, increased progressively to the peak levels in spawning phase and then declined. The brain and ovarian comt mRNA levels showed periovulatory changes after in vivo and in vitro human chorionic gonadotropin (hCG) treatments with high fold increases at 16 and 24h in the brain and at 16h in the ovary. The catecholestrogen 2-hydroxyE 2 up regulated ovarian comt expression in vitro with the highest fold increase at 16h. The mRNA and protein was localized in the follicular layer of the vitellogenic follicles and in the cytoplasm of primary follicles. The data were discussed in relation to catecholamine and catecholestrogen-mediated functions in the brain and ovary of the stinging catfish. Copyright © 2016 Elsevier Inc. All rights reserved.

Polymorphisms in the dopamine receptor 2 gene region influence improvements during working memory training in children and adolescents.

PubMed

Söderqvist, Stina; Matsson, Hans; Peyrard-Janvid, Myriam; Kere, Juha; Klingberg, Torkel

2014-01-01

Studying the effects of cognitive training can lead to finding better treatments, but it can also be a tool for investigating factors important for brain plasticity and acquisition of cognitive skills. In this study, we investigated how single-nucleotide polymorphisms (SNPs) and ratings of intrinsic motivation were associated to interindividual differences in improvement during working memory training. The study included 256 children aged 7-19 years who were genotyped for 13 SNPs within or near eight candidate genes previously implicated in learning: COMT, SLC6A3 (DAT1), DRD4, DRD2, PPP1R1B (DARPP32), MAOA, LMX1A, and BDNF. Ratings on the intrinsic motivation inventory were also available for 156 of these children. All participants performed at least 20 sessions of working memory training, and performance during the training was logged and used as the outcome variable. We found that two SNPs, rs1800497 and rs2283265, located near and within the dopamine receptor 2 (DRD2) gene, respectively, were significantly associated with improvements during training (p < .003 and p < .0004, respectively). Scores from a questionnaire regarding intrinsic motivation did not correlate with training outcome. However, we observed both the main effect of genotype at those two loci as well as the interaction between genotypes and ratings of intrinsic motivation (perceived competence). Both SNPs have previously been shown to affect DRD2 receptor density primarily in the BG. Our results suggest that genetic variation is accounting for some interindividual differences in how children acquire cognitive skills and that part of this effect is also seen on intrinsic motivation. Moreover, they suggest that dopamine D2 transmission in the BG is a key factor for cognitive plasticity.

APOE, MAPT, and COMT and Parkinson's Disease Susceptibility and Cognitive Symptom Progression.

PubMed

Paul, Kimberly C; Rausch, Rebecca; Creek, Michelle M; Sinsheimer, Janet S; Bronstein, Jeff M; Bordelon, Yvette; Ritz, Beate

2016-04-02

Cognitive decline is well recognized in Parkinson's disease (PD) and a major concern for patients and caregivers. Apolipoprotein E (APOE), catechol-O-methyl transferase (COMT), and microtubule-associated protein tau (MAPT) are of interest related to their contributions to cognitive decline or dementia in PD. Here, we investigate whether APOE, COMT, or MAPT influence the rate of cognitive decline in PD patients. We relied on 634 PD patients and 879 controls to examine gene-PD susceptibility associations, and nested longitudinal cohort of 246 patients from the case-control study, which followed patients on average 5 years and 7.5 years into disease. We repeatedly assessed cognitive symptom progression with the MMSE and conducted a full neuropsychological battery on a subset of 183 cognitively normal patients. We used repeated-measures regression analyses to assess longitudinal associations between genotypes and cognitive progression scores. The MAPT H1 haplotype was associated with PD susceptibility. APOE 4 carriers (ɛ4+) (p = 0.03) and possibly COMT Met/Met (p = 0.06) carriers exhibited faster annual decline on the MMSE. Additionally, APOEɛ4+ carriers showed faster decline in many of the neuropsychological test scores. No such differences in neuropsychological outcomes were seen for the COMT genotypes. This work supports a growing set of research identifying overlapping etiology and pathology between synucleinopathies, such as PD, Alzheimer's disease, and tauopathies, especially in the context of cognitive dysfunction in PD. We provide support for the argument that APOE ɛ4+ and COMT Met/Met genotypes can be used as predictors of faster cognitive decline in PD.

Chloroplast overexpression of rice caffeic acid O-methyltransferase increases melatonin production in chloroplasts via the 5-methoxytryptamine pathway in transgenic rice plants.

PubMed

Choi, Geun-Hee; Lee, Hyoung Yool; Back, Kyoungwhan

2017-08-01

Recent analyses of the enzymatic features of various melatonin biosynthetic genes from bacteria, animals, and plants have led to the hypothesis that melatonin could be synthesized via the 5-methoxytryptamine (5-MT) pathway. 5-MT is known to be synthesized in vitro from serotonin by the enzymatic action of O-methyltransferases, including N-acetylserotonin methyltransferase (ASMT) and caffeic acid O-methyltransferase (COMT), leading to melatonin synthesis by the subsequent enzymatic reaction with serotonin N-acetyltransferase (SNAT). Here, we show that 5-MT was produced and served as a precursor for melatonin synthesis in plants. When rice seedlings were challenged with senescence treatment, 5-MT levels and melatonin production were increased in transgenic rice seedlings overexpressing the rice COMT in chloroplasts, while no such increases were observed in wild-type or transgenic seedlings overexpressing the rice COMT in the cytosol, suggesting a 5-MT transport limitation from the cytosol to chloroplasts. In contrast, cadmium treatment led to results different from those in senescence. The enhanced melatonin production was not observed in the chloroplast COMT lines relative over the cytosol COMT lines although 5-MT levels were equally induced in all genotypes upon cadmium treatment. The transgenic seedlings with enhanced melatonin in their chloroplasts exhibited improved seedling growth vs the wild type under continuous light conditions. This is the first report describing enhanced melatonin production in chloroplasts via the 5-MT pathway with the ectopic overexpression of COMT in chloroplasts in plants. © 2017 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Genetic Correlates of Maladaptive Beliefs: COMT VAL(158)MET and Irrational Cognitions Linked Depending on Distress.

PubMed

Podina, Ioana; Popp, Radu; Pop, Ioan; David, Daniel

2015-11-01

Maladaptive/irrational beliefs are significant cognitive vulnerability mechanisms in psychopathology. They are more likely to be associated with a genetic vulnerability marker under conditions of emotional distress when irrational beliefs are more salient. Therefore, in the current study we investigated the COMT Val(158)Met gene variation in relation to irrational beliefs, assuming this relationship depended on the level of emotional distress. Two hundred and sixty-seven genotyped volunteers were assessed for core/general maladaptive beliefs, as well as trait emotional distress. We focused on context-independent measures of irrational beliefs and emotional distress in the absence of a stressor. As expected, the relationship between COMT Val(158)Met and irrational beliefs depended on the level of emotional distress (f(2)=.314). The COMT Val(158)Met-irrationality association was significant only when individuals fell in the average to above average range of emotional distress. Furthermore, within this range the Met allele seemed to relate to higher irrational beliefs. These results were significant for overall irrational beliefs and its subtypes, but not for rational beliefs, the functional counterpart of irrationality. In light of the study's limitations, the results should be considered as preliminary. If replicable, these findings have potential implications for therapygenetics, changing the view that COMT Val(158)Met might be of greater relevance when treatment modality does not rely on cognitive variables. Copyright © 2015. Published by Elsevier Ltd.

Genetics of Lesch's typology of alcoholism.

PubMed

Samochowiec, Jerzy; Kucharska-Mazur, Jolanta; Grzywacz, Anna; Pelka-Wysiecka, Justyna; Mak, Monika; Samochowiec, Agnieszka; Bienkowski, Przemyslaw

2008-02-15

It is widely accepted that dopamine and serotonin (5-HT) neurotransmission can be critically involved in the development of alcohol abuse and alcohol dependence. Lesch's typology of alcoholism has been gaining increasing popularity as it qualitatively differentiates patients into different treatment response subgroups. The aim of the present study was to evaluate a possible genetic background of Lesch's typology with special emphasis placed on dopamine- and serotonin-related genes. 122 alcoholics (the mean age: 35+/-9 years) were investigated. According to Lesch's typology, 58 patients were of type I, 36 patients of type II, 11 patients of type III, and 17 patients of type IV. Alcohol drinking and family history was assessed by means of a structured interview, based on the Semi-Structured Assessment for the Genetics of Alcoholism. 150 control subjects without psychiatric disorders were also recruited. The control group was ethnically-, age- and gender-matched to the patients. The DRD2 TaqIA, exon 8, and promoter -141C ins/del polymorphisms as well as COMT Val158Met, 5HTT 44 bp del in promoter, and DAT 40 bp VNTR polymorphisms were detected by means of PCR. No significant differences were observed when the whole group of alcoholics and the controls were compared. Similarly, there were no differences between either the Lesch type I or type II alcoholics and the control subjects. No significant differences were observed between type I and type II alcoholics. Alleles frequencies were not calculated for the Lesch type III and type IV alcoholics since the number of patients was too small. The present results argue against any major role of the investigated polymorphisms in either Lesch type I or type II alcoholism. More comprehensive studies are needed to define the role of the investigated polymorphisms in Lesch type III and type IV alcoholism.

Associations between neurodevelopmental genes, neuroanatomy, and ultra high risk symptoms of psychosis in 22q11.2 deletion syndrome.

PubMed

Thompson, Carlie A; Karelis, Jason; Middleton, Frank A; Gentile, Karen; Coman, Ioana L; Radoeva, Petya D; Mehta, Rashi; Fremont, Wanda P; Antshel, Kevin M; Faraone, Stephen V; Kates, Wendy R

2017-04-01

22q11.2 deletion syndrome is a neurogenetic disorder resulting in the deletion of over 40 genes. Up to 40% of individuals with 22q11.2DS develop schizophrenia, though little is known about the underlying mechanisms. We hypothesized that allelic variation in functional polymorphisms in seven genes unique to the deleted region would affect lobar brain volumes, which would predict risk for psychosis in youth with 22q11.2DS. Participants included 56 individuals (30 males) with 22q11.2DS. Anatomic MR images were collected and processed using Freesurfer. Participants were genotyped for 10 SNPs in the COMT, DGCR8, GNB1L, PIK4CA, PRODH, RTN4R, and ZDHHC8 genes. All subjects were assessed for ultra high risk symptoms of psychosis. Allelic variation of the rs701428 SNP of RTN4R was significantly associated with volumetric differences in gray matter of the lingual gyrus and cuneus of the occipital lobe. Moreover, occipital gray matter volumes were robustly associated with ultra high risk symptoms of psychosis in the presence of the G allele of rs701428. Our results suggest that RTN4R, a relatively under-studied gene at the 22q11 locus, constitutes a susceptibility gene for psychosis in individuals with this syndrome through its alteration of the architecture of the brain. © 2017 Wiley Periodicals, Inc. © 2017 Wiley Periodicals, Inc.

COMT Diplotype Amplifies Effect of Stress on Risk of Temporomandibular Pain.

PubMed

Slade, G D; Sanders, A E; Ohrbach, R; Bair, E; Maixner, W; Greenspan, J D; Fillingim, R B; Smith, S; Diatchenko, L

2015-09-01

When measured once, psychological stress predicts development of painful temporomandibular disorder (TMD). However, a single measurement fails to characterize the dynamic nature of stress over time. Moreover, effects of stress on pain likely vary according to biological susceptibility. We hypothesized that temporal escalation in stress exacerbates risk for TMD, and the effect is amplified by allelic variants in a gene, catechol-O-methyltransferase (COMT), regulating catechol neurotransmitter catabolism. We used data from the Orofacial Pain: Prospective Evaluation and Risk Assessment prospective cohort study of 2,707 community-dwelling adults with no lifetime history of TMD on enrollment. At baseline and quarterly periods thereafter, the Perceived Stress Scale (PSS) measured psychological stress. Genotyped DNA from blood samples determined COMT diplotypes. During follow-up of 0.25 to 5.2 y, 248 adults developed examiner-verified incident TMD. PSS scores at baseline were 20% greater (P < 0.001) in adults who developed incident TMD compared with TMD-free controls. Baseline PSS scores increased by 9% (P = 0.003) during follow-up in cases but remained stable in controls. This stress escalation was limited to incident cases with COMT diplotypes coding for low-activity COMT, signifying impaired catabolism of catecholamines. Cox regression models confirmed significant effects on TMD hazard of both baseline PSS (P < 0.001), modeled as a time-constant covariate, and change in PSS (P < 0.001), modeled as a time-varying covariate. Furthermore, a significant (P = 0.04) interaction of COMT diplotype and time-varying stress showed that a postbaseline increase of 1.0 standard deviation in PSS more than doubled risk of TMD incidence in subjects with low-activity COMT diplotypes (hazard ratio = 2.35; 95% confidence limits: 1.66, 3.32), an effect not found in subjects with high-activity COMT diplotypes (hazard ratio = 1.42; 95% confidence limits: 0.96, 2.09). Findings provide novel insights into dynamic effects of psychological stress on TMD pain, highlighting that effects are most pronounced in individuals whose genetic susceptibility increases responsiveness to catecholamine neurotransmitters. © International & American Associations for Dental Research 2015.

Genetic and environmental factors for hyperhomocysteinaemia and its clinical implications in Parkinson's disease.

PubMed

Białecka, Monika; Robowski, Piotr; Honczarenko, Krystyna; Roszmann, Anna; Sławek, Jarosław

2009-01-01

Elevated homocysteine (Hcy) plasma levels are caused by genetic and environmental factors. Polymorphisms of Hcy metabolizing enzyme genes may result in its plasma increase. Experimental and clinical studies have shown the possible role of hyperhomocysteinaemia in pathogenesis of Parkinson's disease (PD), Alzheimer's disease and vascular disorders. The results of clinical studies in PD generally do not support the theoretical hypotheses, and animal studies remain controversial. A major environmental factor responsible for Hcy increase in PD seems to be levodopa therapy. Its metabolism results in Hcy increase and may be reduced with folate and vitamins B6, B12 supplementation or inhibition of catechol-O-methyltransferase (COMT) activity. Therefore, the potential harmful role of Hcy may be diminished in PD patients with vascular comorbidities. Further studies are needed to establish the real role of Hcy for PD and other neurological disorders. The paper summarizes the current knowledge on the genetic and environmental factors responsible for Hcy increase in PD.

Linking unfounded beliefs to genetic dopamine availability

PubMed Central

Schmack, Katharina; Rössler, Hannes; Sekutowicz, Maria; Brandl, Eva J.; Müller, Daniel J.; Petrovic, Predrag; Sterzer, Philipp

2015-01-01

Unfounded convictions involving beliefs in the paranormal, grandiosity ideas or suspicious thoughts are endorsed at varying degrees among the general population. Here, we investigated the neurobiopsychological basis of the observed inter-individual variability in the propensity toward unfounded beliefs. One hundred two healthy individuals were genotyped for four polymorphisms in the COMT gene (rs6269, rs4633, rs4818, and rs4680, also known as val158met) that define common functional haplotypes with substantial impact on synaptic dopamine degradation, completed a questionnaire measuring unfounded beliefs, and took part in a behavioral experiment assessing perceptual inference. We found that greater dopamine availability was associated with a stronger propensity toward unfounded beliefs, and that this effect was statistically mediated by an enhanced influence of expectations on perceptual inference. Our results indicate that genetic differences in dopaminergic neurotransmission account for inter-individual differences in perceptual inference linked to the formation and maintenance of unfounded beliefs. Thus, dopamine might be critically involved in the processes underlying one's interpretation of the relationship between the self and the world. PMID:26483654

Time course field analysis of COMT-downregulated switchgrass: Lignification, recalcitrance, and rust susceptibility

DOE PAGES

Baxter, Holly L.; Mazarei, Mitra; Fu, Chunxiang; ...

2016-05-18

Modifying plant cell walls by manipulating lignin biosynthesis can improve biofuel yields from lignocellulosic crops. For example, transgenic switchgrass lines with downregulated expression of caffeic acid O-methyltransferase, a lignin biosynthetic enzyme, produce up to 38% more ethanol than controls. The aim of the present study was to understand cell wall lignification over the second and third growing seasons of COMT-downregulated field-grown switchgrass. COMT gene expression, lignification, and cell wall recalcitrance were assayed for two independent transgenic lines at monthly intervals. Switchgrass rust (Puccinia emaculata) incidence was also tracked across the seasons. Trends in lignification over time differed between the 2more » years. In 2012, sampling was initiated in mid-growing season on reproductive-stage plants and there was little variation in the lignin content of all lines (COMT-downregulated and control) over time. COMT-downregulated lines maintained 11-16% less lignin, 33-40% lower S/G (syringyl-to-guaiacyl) ratios, and 15-42% higher sugar release relative to controls for all time points. In 2013, sampling was initiated earlier in the season on elongation-stage plants and the lignin content of all lines steadily increased over time, while sugar release expectedly decreased. S/G ratios increased in non-transgenic control plants as biomass accumulated over the season, while remaining relatively stable across the season in the COMT-downregulated lines. Differences in cell wall chemistry between transgenic and non-transgenic lines were not apparent until plants transitioned to reproductive growth in mid-season, after which the cell walls of COMT-downregulated plants exhibited phenotypes consistent with what was observed in 2012. There were no differences in rust damage between transgenics and controls at any time point. Finally, these results provide relevant fundamental insights into the process of lignification in a maturing field-grown biofuel feedstock with downregulated lignin biosynthesis.« less

Time course field analysis of COMT-downregulated switchgrass: Lignification, recalcitrance, and rust susceptibility

DOE Office of Scientific and Technical Information (OSTI.GOV)

Baxter, Holly L.; Mazarei, Mitra; Fu, Chunxiang

Modifying plant cell walls by manipulating lignin biosynthesis can improve biofuel yields from lignocellulosic crops. For example, transgenic switchgrass lines with downregulated expression of caffeic acid O-methyltransferase, a lignin biosynthetic enzyme, produce up to 38% more ethanol than controls. The aim of the present study was to understand cell wall lignification over the second and third growing seasons of COMT-downregulated field-grown switchgrass. COMT gene expression, lignification, and cell wall recalcitrance were assayed for two independent transgenic lines at monthly intervals. Switchgrass rust (Puccinia emaculata) incidence was also tracked across the seasons. Trends in lignification over time differed between the 2more » years. In 2012, sampling was initiated in mid-growing season on reproductive-stage plants and there was little variation in the lignin content of all lines (COMT-downregulated and control) over time. COMT-downregulated lines maintained 11-16% less lignin, 33-40% lower S/G (syringyl-to-guaiacyl) ratios, and 15-42% higher sugar release relative to controls for all time points. In 2013, sampling was initiated earlier in the season on elongation-stage plants and the lignin content of all lines steadily increased over time, while sugar release expectedly decreased. S/G ratios increased in non-transgenic control plants as biomass accumulated over the season, while remaining relatively stable across the season in the COMT-downregulated lines. Differences in cell wall chemistry between transgenic and non-transgenic lines were not apparent until plants transitioned to reproductive growth in mid-season, after which the cell walls of COMT-downregulated plants exhibited phenotypes consistent with what was observed in 2012. There were no differences in rust damage between transgenics and controls at any time point. Finally, these results provide relevant fundamental insights into the process of lignification in a maturing field-grown biofuel feedstock with downregulated lignin biosynthesis.« less

Dopamine receptor D2 (DRD2), dopamine transporter solute carrier family C6, member 4 (SLC6A3), and catechol-O-methyltransferase (COMT) genes as moderators of the relation between maternal history of maltreatment and infant emotion regulation.

PubMed

Villani, Vanessa; Ludmer, Jaclyn; Gonzalez, Andrea; Levitan, Robert; Kennedy, James; Masellis, Mario; Basile, Vincenzo S; Wekerle, Christine; Atkinson, Leslie

2018-05-01

Although infants less than 18 months old are capable of engaging in self-regulatory behavior (e.g., avoidance, withdrawal, and orienting to other aspects of their environment), the use of self-regulatory strategies at this age (as opposed to relying on caregivers) is associated with elevated behavioral and physiological distress. This study investigated infant dopamine-related genotypes (dopamine receptor D2 [DRD2], dopamine transporter solute carrier family C6, member 4 [SLC6A3], and catechol-O-methyltransferase [COMT]) as they interact with maternal self-reported history of maltreatment to predict observed infant independent emotion regulation behavior. A community sample (N = 193) of mother-infant dyads participated in a toy frustration challenge at infant age 15 months, and infant emotion regulation behavior was coded. Buccal cells were collected for genotyping. Maternal maltreatment history significantly interacted with infant SLC6A3 and COMT genotypes, such that infants with more 10-repeat and valine alleles of SLC6A3 and COMT, respectively, relative to infants with fewer or no 10-repeat and valine alleles, utilized more independent (i.e., maladaptive) regulatory behavior if mother reported a more extensive maltreatment history, as opposed to less. The findings indicate that child genetic factors moderate the intergenerational impact of maternal maltreatment history. The results are discussed in terms of potential mechanism of Gene × Environment interaction.

Determination of the Structure and Catalytic Mechanism of Sorghum bicolor Caffeic Acid O-Methyltransferase and the Structural Impact of Three brown midrib12 Mutations1[W

PubMed Central

Green, Abigail R.; Lewis, Kevin M.; Barr, John T.; Jones, Jeffrey P.; Lu, Fachuang; Ralph, John; Vermerris, Wilfred; Sattler, Scott E.; Kang, ChulHee

2014-01-01

Using S-adenosyl-methionine as the methyl donor, caffeic acid O-methyltransferase from sorghum (Sorghum bicolor; SbCOMT) methylates the 5-hydroxyl group of its preferred substrate, 5-hydroxyconiferaldehyde. In order to determine the mechanism of SbCOMT and understand the observed reduction in the lignin syringyl-to-guaiacyl ratio of three brown midrib12 mutants that carry COMT gene missense mutations, we determined the apo-form and S-adenosyl-methionine binary complex SbCOMT crystal structures and established the ternary complex structure with 5-hydroxyconiferaldehyde by molecular modeling. These structures revealed many features shared with monocot ryegrass (Lolium perenne) and dicot alfalfa (Medicago sativa) COMTs. SbCOMT steady-state kinetic and calorimetric data suggest a random bi-bi mechanism. Based on our structural, kinetic, and thermodynamic results, we propose that the observed reactivity hierarchy among 4,5-dihydroxy-3-methoxycinnamyl (and 3,4-dihydroxycinnamyl) aldehyde, alcohol, and acid substrates arises from the ability of the aldehyde to stabilize the anionic intermediate that results from deprotonation of the 5-hydroxyl group by histidine-267. Additionally, despite the presence of other phenylpropanoid substrates in vivo, sinapaldehyde is the preferential product, as demonstrated by its low Km for 5-hydroxyconiferaldehyde. Unlike its acid and alcohol substrates, the aldehydes exhibit product inhibition, and we propose that this is due to nonproductive binding of the S-cis-form of the aldehydes inhibiting productive binding of the S-trans-form. The S-cis-aldehydes most likely act only as inhibitors, because the high rotational energy barrier around the 2-propenyl bond prevents S-trans-conversion, unlike alcohol substrates, whose low 2-propenyl bond rotational energy barrier enables rapid S-cis/S-trans-interconversion. PMID:24948836

Monoamine oxidase A gene polymorphisms and enzyme activity associated with risk of gout in Taiwan aborigines.

PubMed

Tu, Hung-Pin; Ko, Albert Min-Shan; Wang, Shu-Jung; Lee, Chien-Hung; Lea, Rod A; Chiang, Shang-Lun; Chiang, Hung-Che; Wang, Tsu-Nai; Huang, Meng-Chuan; Ou, Tsan-Teng; Lin, Gau-Tyan; Ko, Ying-Chin

2010-02-01

Taiwanese aborigines have a high prevalence of hyperuricemia and gout. Uric acid levels and urate excretion have correlated with dopamine-induced glomerular filtration response. MAOs represent one of the major renal dopamine metabolic pathways. We aimed to identify the monoamine oxidase A (MAOA, Xp11.3) gene variants and MAO-A enzyme activity associated with gout risk. This study was to investigate the association between gout and the MAOA single-nucleotide polymorphisms (SNPs) rs5953210, rs2283725, and rs1137070 as well as between gout and the COMT SNPs rs4680 Val158Met for 374 gout cases and 604 controls. MAO-A activity was also measured. All three MAOA SNPs were significantly associated with gout. A synonymous MAOA SNP, rs1137070 Asp470Asp, located in exon 14, was associated with the risk of having gout (P = 4.0 x 10(-5), adjusted odds ratio 1.46, 95% confidence intervals [CI]: 1.11-1.91). We also showed that, when compared to individuals with the MAOA GAT haplotype, carriers of the AGC haplotype had a 1.67-fold (95% CI: 1.28-2.17) higher risk of gout. Moreover, we found that MAOA enzyme activity correlated positively with hyperuricemia and gout (P for trend = 2.00 x 10(-3) vs. normal control). We also found that MAOA enzyme activity by rs1137070 allele was associated with hyperuricemia and gout (P for trend = 1.53 x 10(-6) vs. wild-type allele). Thus, our results show that some MAOA alleles, which have a higher enzyme activity, predispose to the development of gout.

COMBINE genetics study: the pharmacogenetics of alcoholism treatment response: genes and mechanisms.

PubMed

Goldman, David; Oroszi, Gabor; O'Malley, Stephanie; Anton, Raymond

2005-07-01

Partial efficacy of treatment and differences in adverse events across individuals are a challenge and an opportunity in the treatment of alcoholism. Individuation of therapy and understanding origins of differential treatment response may require identification of inherited functional variants of genes. The neurobiology of reward, executive cognitive function, anxiety and dysphoria have been identified as critical domains that may have a genetic basis that could predict treatment response. The COMBINE Study presents a unique opportunity to evaluate specific genetic loci (markers) that affect neurobiology central to addiction and extended withdrawal. The study also addresses variation in drug metabolism and action. Candidate genetic markers are selected for study based on functionality and abundance. COMT Vall58Met is a common (minor allele frequency 0.42), functional, catecholamine-metabolizing enzyme polymorphism with threefold relevance. Vall58Met alters executive cognitive function, stress and anxiety responses and brain endogenous opioid function. OPRM1 Asn40Asp is a common (minor allele frequency 0.10), functional polymorphism of the mu-opioid receptor, which may serve as a gatekeeper molecule in naltrexone's actions and was recently reported to affect naltrexone response. HTTLPR (minor allele frequency 0.40) alters serotonin transporter function to affect anxiety, dysphoria and obsessional behavior, which are assessed in COMBINE and may be related to relapse and addictive behavior. All genetic testing is consented through a separate human research protocol, and the testing is conducted nonclinically, confidentially and apart from the clinical record to protect human research participants who have volunteered for this aspect of COMBINE.

Aggressive behavior, related conduct problems, and variation in genes affecting dopamine turnover.

PubMed

Grigorenko, Elena L; De Young, Colin G; Eastman, Maria; Getchell, Marya; Haeffel, Gerald J; Klinteberg, Britt af; Koposov, Roman A; Oreland, Lars; Pakstis, Andrew J; Ponomarev, Oleg A; Ruchkin, Vladislav V; Singh, Jay P; Yrigollen, Carolyn M

2010-01-01

A number of dopamine-related genes have been implicated in the etiology of violent behavior and conduct problems. Of these genes, the ones that code for the enzymes that influence the turnover of dopamine (DA) have received the most attention. In this study, we investigated 12 genetic polymorphisms in four genes involved with DA functioning (COMT, MAOA and MAOB, and DbetaH) in 179 incarcerated male Russian adolescents and two groups of matched controls: boys without criminal records referred to by their teachers as (a) "troubled-behavior-free" boys, n=182; and (b) "troubled-behavior" boys, n=60. The participants were classified as (1) being incarcerated or not, (2) having the DSM-IV diagnosis of conduct disorder (CD) or not, and (3) having committed violent or nonviolent crimes (for the incarcerated individuals only). The findings indicate that, although no single genetic variant in any of the four genes differentiated individuals in the investigated groups, various linear combinations (i.e., haplotypes) and nonlinear combinations (i.e., interactions between variants within and across genes) of genetic variants resulted in informative and robust classifications for two of the three groupings. These combinations of genetic variants differentiated individuals in incarceration vs. nonincarcerated and CD vs. no-CD groups; no informative combinations were established consistently for the grouping by crime within the incarcerated individuals. This study underscores the importance of considering multiple rather than single markers within candidate genes and their additive and interactive combinations, both with themselves and with nongenetic indicators, while attempting to understand the genetic background of such complex behaviors as serious conduct problems. (c) 2010 Wiley-Liss, Inc.

Cigarettes, genetic background, and menopausal timing: the presence of single nucleotide polymorphisms in cytochrome P450 genes is associated with increased risk of natural menopause in European-American smokers.

PubMed

Butts, Samantha F; Sammel, Mary D; Greer, Christine; Rebbeck, Timothy R; Boorman, David W; Freeman, Ellen W

2014-07-01

This study aims to evaluate associations between variations in genes involved in the metabolism of environmental chemicals and steroid hormones and risk of menopause in smokers. Survival analysis was performed on 410 eligible participants from the Penn Ovarian Aging study (ongoing for 14 years), a cohort study of late-reproductive-age women. Single nucleotide polymorphisms at the following loci were studied: COMT Val158Met, CYP1B1*4 Asn452Ser, CYP1B1*3 Leu432Val, and CYP3A4*1B. Significant interactions between smoking and single nucleotide polymorphisms were observed in European-American carriers of CYP3A4*1B and CYP1B1*3, supporting a greater risk of menopause entry compared with those not carrying these alleles. Among CYP1B1*3 carriers, smokers had a greater risk of menopause entry than nonsmokers (adjusted hazard ratio [HR], 2.26; 95% CI, 1.4-3.67; median time to menopause, 10.42 and 11.07 y, respectively). No association between smoking and menopause was identified in CYP1B1 wild types. Among CYP3A4*1B carriers, smokers were at greater risk for menopause entry than nonsmokers (adjusted HR, 15.1; 95% CI, 3.31-69.2; median time to menopause, 11.36 and 13.91 y, respectively). Risk of menopause entry in CYP3A4 wild types who smoked was far lower (adjusted HR, 1.59; 95% CI, 1.03-2.44). Heavily smoking CYP1B1*3 carriers (adjusted HR, 3.0; 95% CI, 1.54-5.84; median time to menopause, 10.41 y) and heavily smoking CYP3A4*1B carriers (adjusted HR, 17.79; 95% CI, 3.21-98.65; median time to menopause, 5.09 y) had the greatest risk of menopause entry. Our finding that the risk of menopause entry in European-American smokers varies depending on genetic background represents a novel gene-environment interaction in reproductive aging.

Cigarettes, genetic background, and menopausal timing: the presence of single nucleotide polymorphisms in cytochrome P450 genes is associated with increased risk of natural menopause in European-American smokers

PubMed Central

Butts, Samantha F.; Sammel, Mary D.; Greer, Christine; Rebbeck, Timothy R.; Boorman, David W.; Freeman, Ellen W.

2016-01-01

Objective This study aims to evaluate associations between variations in genes involved in the metabolism of environmental chemicals and steroid hormones and risk of menopause in smokers. Methods Survival analysis was performed on 410 eligible participants from the Penn Ovarian Aging study (ongoing for 14 years), a cohort study of late-reproductive-age women. Single nucleotide polymorphisms at the following loci were studied: COMT Val158Met, CYP1B1*4 Asn452Ser, CYP1B1*3 Leu432Val, and CYP3A4*1B. Results Significant interactions between smoking and single nucleotide polymorphisms were observed in European-American carriers of CYP3A4*1B and CYP1B1*3, supporting a greater risk of menopause entry compared with those not carrying these alleles. Among CYP1B1*3 carriers, smokers had a greater risk of menopause entry than nonsmokers (adjusted hazard ratio [HR], 2.26; 95% CI, 1.4–3.67; median time to menopause, 10.42 and 11.07 y, respectively). No association between smoking and menopause was identified in CYP1B1 wild types. Among CYP3A4*1B carriers, smokers were at greater risk for menopause entry than nonsmokers (adjusted HR, 15.1; 95% CI, 3.31–69.2; median time to menopause, 11.36 and 13.91 y, respectively). Risk of menopause entry in CYP3A4 wild types who smoked was far lower (adjusted HR, 1.59; 95% CI, 1.03–2.44). Heavily smoking CYP1B1*3 carriers (adjusted HR, 3.0; 95% CI, 1.54–5.84; median time to menopause, 10.41 y) and heavily smoking CYP3A4*1B carriers (adjusted HR, 17.79; 95% CI, 3.21–98.65; median time to menopause, 5.09 y) had the greatest risk of menopause entry. Conclusions Our finding that the risk of menopause entry in European-American smokers varies depending on genetic background represents a novel gene-environment interaction in reproductive aging. PMID:24448104

Genetics of generalized anxiety disorder and related traits.

PubMed

Gottschalk, Michael G; Domschke, Katharina

2017-06-01

This review serves as a systematic guide to the genetics of generalized anxiety disorder (GAD) and further focuses on anxiety-relevant endophenotypes, such as pathological worry fear of uncertainty, and neuroticism. We inspect clinical genetic evidence for the familialityl heritability of GAD and cross-disorder phenotypes based on family and twin studies. Recent advances of linkage studies, genome-wide association studies, and candidate gene studies (eg, 5-HTT, 5-HT1A, MAOA, BDNF ) are outlined. Functional and structural neuroimaging and neurophysiological readouts relating to peripheral stress markers and psychophysiology are further integrated, building a multilevel disease framework. We explore etiologic factors in gene-environment interaction approaches investigating childhood trauma, environmental adversity, and stressful life events in relation to selected candidate genes ( 5-HTT, NPSR1, COMT, MAOA, CRHR1, RGS2 ), Additionally, the pharmacogenetics of selective serotonin reuptake inhibitor/serotonin-norepinephrine reuptake inhibitor treatment are summarized ( 5-HTT, 5-HT2A, COMT, CRHR1 ). Finally, GAD and trait anxiety research challenges and perspectives in the field of genetics, including epigenetics, are discussed.

Ethnicity-dependent influence of innate immune genetic markers on morphine PCA requirements and adverse effects in postoperative pain.

PubMed

Somogyi, Andrew A; Sia, Alex T; Tan, Ene-Choo; Coller, Janet K; Hutchinson, Mark R; Barratt, Daniel T

2016-11-01

Although several genetic factors have been associated with postsurgical morphine requirements, those involving the innate immune system and cytokines have not been well investigated. The aim of this study was to investigate the contribution of genetic variability in innate immune signalling pathways to variability in morphine dosage after elective caesarean section under spinal anaesthesia in 133 Indian, 230 Malay, and 598 Han Chinese women previously studied. Twenty single nucleotide polymorphisms in 14 genes involved in glial activation (TLR2, TLR4, MYD88, MD2), inflammatory signalling (IL2, IL6, IL10, IL1B, IL6R, TNFA, TGFB1, CRP, CASP1), and neuronal regulation (BDNF) were newly investigated, in addition to OPRM1, COMT, and ABCB1 genetic variability identified previously. Postsurgical patient-controlled analgesia morphine use (mg/24 hours) was binned into 6 normally distributed groups and scored 0 to 5 to facilitate step-down multiple linear regression analysis of genetic predictors, controlling for ethnicity and nongenetic variables. Ethnicity, OPRM1 rs1799971 (increased), TLR2 rs3804100 (decreased), and an interaction between ethnicity and IL1B rs1143634 (increased), predicted 9.8% of variability in morphine use scores in the entire cohort. In the Indian cohort, 14.5% of the variance in morphine use score was explained by IL1B rs1143634 (increased) and TGFB1 rs1800469 (decreased). In Chinese patients, the incidence of postsurgical pain was significantly higher in variant COMT rs4680 genotypes (P = 0.0007) but not in the Malay or Indian cohorts. Innate immune genetics may contribute to variability in postsurgical opioid requirements in an ethnicity-dependent manner.

Genetic variants in TPMT and COMT are associated with hearing loss in children receiving cisplatin chemotherapy.

PubMed

Ross, Colin J D; Katzov-Eckert, Hagit; Dubé, Marie-Pierre; Brooks, Beth; Rassekh, S Rod; Barhdadi, Amina; Feroz-Zada, Yassamin; Visscher, Henk; Brown, Andrew M K; Rieder, Michael J; Rogers, Paul C; Phillips, Michael S; Carleton, Bruce C; Hayden, Michael R

2009-12-01

Cisplatin is a widely used and effective chemotherapeutic agent, although its use is restricted by the high incidence of irreversible ototoxicity associated with it. In children, cisplatin ototoxicity is a serious and pervasive problem, affecting more than 60% of those receiving cisplatin and compromising language and cognitive development. Candidate gene studies have previously reported associations of cisplatin ototoxicity with genetic variants in the genes encoding glutathione S-transferases and megalin. We report association analyses for 220 drug-metabolism genes in genetic susceptibility to cisplatin-induced hearing loss in children. We genotyped 1,949 SNPs in these candidate genes in an initial cohort of 54 children treated in pediatric oncology units, with replication in a second cohort of 112 children recruited through a national surveillance network for adverse drug reactions in Canada. We identified genetic variants in TPMT (rs12201199, P value = 0.00022, OR = 17.0, 95% CI 2.3-125.9) and COMT (rs9332377, P value = 0.00018, OR = 5.5, 95% CI 1.9-15.9) associated with cisplatin-induced hearing loss in children.

Delayed O-methylation of l-DOPA in MB-COMT-deficient mice after oral administration of l-DOPA and carbidopa.

PubMed

Tammimäki, Anne; Aonurm-Helm, Anu; Männistö, Pekka T

2018-04-01

1. Catechol-O-methyltransferase (COMT) is involved in the O-methylation of l-DOPA, dopamine, and other catechols. The enzyme is expressed in two isoforms: soluble (S-COMT), which resides in the cytoplasm, and membrane-bound (MB-COMT), which is anchored to intracellular membranes. 2. To obtain specific information on the functions of COMT isoforms, we studied how a complete MB-COMT deficiency affects the total COMT activity in the body, peripheral l-DOPA levels, and metabolism after l-DOPA (10 mg kg -1 ) plus carbidopa (30 mg kg -1 ) administration by gastric tube in wild-type (WT) and MB-COMT-deficient mice. l-DOPA and 3-O-methyl-l-DOPA (3-OMD) levels were assayed in plasma, duodenum, and liver. 3. We showed that the selective lack of MB-COMT did not alter the total COMT activity, COMT enzyme kinetics, l-DOPA levels, or the total O-methylation of l-DOPA but delayed production of 3-OMD in plasma and peripheral tissues.

SERT Ileu425Val in autism, Asperger syndrome and obsessive-compulsive disorder.

PubMed

Wendland, Jens R; DeGuzman, Theresa B; McMahon, Francis; Rudnick, Gary; Detera-Wadleigh, Sevilla D; Murphy, Dennis L

2008-02-01

SERT I425V, an uncommon missense single nucleotide polymorphism producing a gain-of-function of the serotonin transporter (SERT), was originally found to segregate with a primarily obsessive-compulsive disorder (OCD) but complexly comorbid phenotype in two unrelated families. As two individuals with SERT I425V and OCD also had Asperger syndrome (AS), an autism spectrum disorder, and as other rare SERT variants have recently shown significant associations with autism, we set out to extend our original OCD study by genotyping additional autism/AS and OCD samples. Case-control association study of SERT I425V in 210 AS/autism probands and 215 controls, plus 335 OCD probands and their family members. SERT I425V was not found in any of the individuals with AS/autism, OCD alone or OCD comorbid with AS and other disorders, or in controls. This results in new estimates of SERT I425V having a 1.5% prevalence in 530 individuals with OCD from five unrelated families genotyped by us and by one other group and a 0.23% frequency in four control populations totaling 1300 individuals, yielding a continuing significant OCD-control difference (Fisher's exact test corrected for family coefficient of identity P=0.004, odds ratio=6.54). As several other uncommon, less well quantitated genetic variations occur with an OCD phenotype, including chromosomal anomalies and some other rare gene variants (SGCE, GCH1 and SLITRK1), a tentative conclusion is that OCD resembles other complex disorders in being etiologically heterogeneous and in having both highly penetrant familial subtypes associated with rare alleles or chromosomal anomalies, as well as having a more common, polygenetic form that may involve polymorphisms in such genes as BDNF, COMT, GRIN2beta, TPH2, HTR2A and SLC1A1.

Determination of the Structure and Catalytic Mechanism of Sorghum bicolor Caffeic Acid O-Methyltransferase and the Structural Impact of Three brown midrib12 Mutations.

PubMed

Green, Abigail R; Lewis, Kevin M; Barr, John T; Jones, Jeffrey P; Lu, Fachuang; Ralph, John; Vermerris, Wilfred; Sattler, Scott E; Kang, ChulHee

2014-08-01

Using S-adenosyl-methionine as the methyl donor, caffeic acid O-methyltransferase from sorghum (Sorghum bicolor; SbCOMT) methylates the 5-hydroxyl group of its preferred substrate, 5-hydroxyconiferaldehyde. In order to determine the mechanism of SbCOMT and understand the observed reduction in the lignin syringyl-to-guaiacyl ratio of three brown midrib12 mutants that carry COMT gene missense mutations, we determined the apo-form and S-adenosyl-methionine binary complex SbCOMT crystal structures and established the ternary complex structure with 5-hydroxyconiferaldehyde by molecular modeling. These structures revealed many features shared with monocot ryegrass (Lolium perenne) and dicot alfalfa (Medicago sativa) COMTs. SbCOMT steady-state kinetic and calorimetric data suggest a random bi-bi mechanism. Based on our structural, kinetic, and thermodynamic results, we propose that the observed reactivity hierarchy among 4,5-dihydroxy-3-methoxycinnamyl (and 3,4-dihydroxycinnamyl) aldehyde, alcohol, and acid substrates arises from the ability of the aldehyde to stabilize the anionic intermediate that results from deprotonation of the 5-hydroxyl group by histidine-267. Additionally, despite the presence of other phenylpropanoid substrates in vivo, sinapaldehyde is the preferential product, as demonstrated by its low K m for 5-hydroxyconiferaldehyde. Unlike its acid and alcohol substrates, the aldehydes exhibit product inhibition, and we propose that this is due to nonproductive binding of the S-cis-form of the aldehydes inhibiting productive binding of the S-trans-form. The S-cis-aldehydes most likely act only as inhibitors, because the high rotational energy barrier around the 2-propenyl bond prevents S-trans-conversion, unlike alcohol substrates, whose low 2-propenyl bond rotational energy barrier enables rapid S-cis/S-trans-interconversion. © 2014 American Society of Plant Biologists. All Rights Reserved.

Catechol-O-Methyltransferase Genotypes and Parenting Influence on Long-Term Executive Functioning After Moderate to Severe Early Childhood Traumatic Brain Injury: An Exploratory Study.

PubMed

Kurowski, Brad G; Treble-Barna, Amery; Zang, Huaiyu; Zhang, Nanhua; Martin, Lisa J; Yeates, Keith Owen; Taylor, H Gerry; Wade, Shari L

To examine catechol-O-methyltransferase (COMT) rs4680 genotypes as moderators of the effects of parenting style on postinjury changes in parent behavior ratings of executive dysfunction following moderate to severe early childhood traumatic brain injury. Research was conducted in an outpatient setting. Participants included children admitted to hospital with moderate to severe traumatic brain injury (n = 55) or orthopedic injuries (n = 70) between ages 3 and 7 years. Prospective cohort followed over 7 years postinjury. Parenting Practices Questionnaire and the Behavior Rating Inventory of Executive Functioning obtained at baseline, 6, 12, and 18 months, and 3.5 and 6.8 years postinjury. DNA was collected from saliva samples, purified using the Oragene (DNA Genotek, Ottawa, Ontario, Canada) OG-500 self-collection tubes, and analyzed using TaqMan (Applied Biosystems, Thermo Fisher Scientific, Waltham, Massachusetts) assay protocols to identify the COMT rs4680 polymorphism. Linear mixed models revealed a significant genotype × parenting style × time interaction (F = 5.72, P = .02), which suggested that the adverse effects of authoritarian parenting on postinjury development of executive functioning were buffered by the presence of the COMT AA genotype (lower enzyme activity, higher dopamine levels). There were no significant associations of executive functioning with the interaction between genotype and authoritative or permissive parenting ratings. The lower activity COMT rs4680 genotype may buffer the negative effect of authoritarian parenting on long-term executive functioning following injury in early childhood. The findings provide preliminary evidence for associations of parenting style with executive dysfunction in children and for a complex interplay of genetic and environmental factors as contributors to decreases in these problems after traumatic injuries in children. Further investigation is warranted to understand the interplay among genetic and environmental factors related to recovery after traumatic brain injury in children.

An entropy-based statistic for genomewide association studies.

PubMed

Zhao, Jinying; Boerwinkle, Eric; Xiong, Momiao

2005-07-01

Efficient genotyping methods and the availability of a large collection of single-nucleotide polymorphisms provide valuable tools for genetic studies of human disease. The standard chi2 statistic for case-control studies, which uses a linear function of allele frequencies, has limited power when the number of marker loci is large. We introduce a novel test statistic for genetic association studies that uses Shannon entropy and a nonlinear function of allele frequencies to amplify the differences in allele and haplotype frequencies to maintain statistical power with large numbers of marker loci. We investigate the relationship between the entropy-based test statistic and the standard chi2 statistic and show that, in most cases, the power of the entropy-based statistic is greater than that of the standard chi2 statistic. The distribution of the entropy-based statistic and the type I error rates are validated using simulation studies. Finally, we apply the new entropy-based test statistic to two real data sets, one for the COMT gene and schizophrenia and one for the MMP-2 gene and esophageal carcinoma, to evaluate the performance of the new method for genetic association studies. The results show that the entropy-based statistic obtained smaller P values than did the standard chi2 statistic.

9th Annual Safar Symposium

DTIC Science & Technology

2012-07-01

residents, medical students, nursing, pharmacy, and undergraduate trainees. Each trainee presentation was judged by an august group of faculty and a total...Environmental Enrichment-Mediated Functional Improvement After Experimental Traumatic Brain Injury." 62 Megan Miller, BS - " COMT Gene Variant

[MODERN VIEWS ON THE PHARMACOGENETICS OF PAIN.

PubMed

Makharin, O A; Zhenilo, V M; Patyuchenko, O Yu

2017-09-01

Quality anesthesia during surgery and in the postoperative period remains a topical problem of modern anesthesiology. The study of genetic characteristics of a patient is a goal that may be allow us to develop a personalized approach to solve this problem. The purpose of the review is a synthesis of literature data about the influence of genetic factors on pain perception and its treatment. The review included information obtained from SCOPUS, MedLine, EMBASE. The search keywords were: pain, pharmacogenetics, polymorphism, analgesics.Describe the effect ofgene polymorphisms of OPRM, 5HTRIA, 5HTR2A, COMT GCHI, SCN9A, KCNSI, CACNA2D3, CACNG2, PTGSI, PTGS2, MDRJ/ABCB] on the perception of pain, and CYP2D6, CYP2C9, CYP3A4 on the pharmacokinetics and pharmacodynamics of medi- cations used in the treatment of pain.

Genetic Risk for Conduct Disorder Symptom Subtypes in an ADHD Sample: Specificity to Aggressive Symptoms

ERIC Educational Resources Information Center

Monuteaux, Michael C.; Biederman, Joseph; Doyle, Alysa E.; Mick, Eric; Faraone, Stephen V.

2009-01-01

Four hundred forty-four subjects aged 6-55 years were evaluated to examine the role of COMT and SLC6A4 genes in the risk for conduct disorder and its symptomatic subtypes in the context of attention deficit hyperactivity disorder. No significant association is found between these genes and the risk for conduct disorder.

Positive symptoms in first-episode psychosis patients experiencing low maternal care and stressful life events: a pilot study to explore the role of the COMT gene.

PubMed

Ira, Elisa; De Santi, Katia; Lasalvia, Antonio; Bonetto, Chiara; Zanatta, Gioia; Cristofalo, Doriana; Bertani, Mariaelena; Bissoli, Sarah Saviana; Riolo, Rossana; Gardellin, Francesco; Morandin, Idana; Ramon, Luana; Tansella, Michele; Ruggeri, Mirella; Tosato, Sarah

2014-09-01

COMT Val(158)Met moderates the effect of stress on psychotic symptoms. Exposure to stress is also associated with mesolimbic dopamine release in individuals experiencing low maternal care. We therefore test the hypothesis that recent stressful life events are associated with more severe positive symptoms (associated with mesolimbic dopamine release) in first-episode psychosis (FEP) patients who experienced low maternal care during childhood. We hypothesized that COMT Val(158)Met moderates this association. A total of 149 FEP patients recruited within the Psychosis Incident Cohort Outcome Study (PICOS) participated in the present study. Maternal care was assessed by the Parental Bonding Instrument (PBI), stressful life events were collected by the List of Events Scale and positive symptoms were assessed by the Positive and Negative Syndrome Scale (PANSS). We found that low maternal care and recent stressful life events were associated with higher level of positive symptoms at the onset (analysis of variance [ANOVA], p = 0.012), and that patients who were also homozygotes for the COMT Val(158) allele had the highest level of positive symptoms (ANOVA, p = 0.024). Low maternal care and severe stressful life events may contribute to a symptomatology characterized by more severe positive symptoms at the onset, possibly due to an increased mesolimbic dopamine release. Homozygosity for the COMT Val(158) allele seems to confer a biological predisposition to the stress-related hyperactivity of the mesolimbic dopaminergic system. The data imply that the mesolimbic dopaminergic system is involved in the mediation/modulation of the effect of stressful events on the vulnerability for psychosis.

Dissociable contribution of prefrontal and striatal dopaminergic genes to learning in economic games

PubMed Central

Set, Eric; Saez, Ignacio; Zhu, Lusha; Houser, Daniel E.; Myung, Noah; Zhong, Songfa; Ebstein, Richard P.; Chew, Soo Hong; Hsu, Ming

2014-01-01

Game theory describes strategic interactions where success of players’ actions depends on those of coplayers. In humans, substantial progress has been made at the neural level in characterizing the dopaminergic and frontostriatal mechanisms mediating such behavior. Here we combined computational modeling of strategic learning with a pathway approach to characterize association of strategic behavior with variations in the dopamine pathway. Specifically, using gene-set analysis, we systematically examined contribution of different dopamine genes to variation in a multistrategy competitive game captured by (i) the degree players anticipate and respond to actions of others (belief learning) and (ii) the speed with which such adaptations take place (learning rate). We found that variation in genes that primarily regulate prefrontal dopamine clearance—catechol-O-methyl transferase (COMT) and two isoforms of monoamine oxidase—modulated degree of belief learning across individuals. In contrast, we did not find significant association for other genes in the dopamine pathway. Furthermore, variation in genes that primarily regulate striatal dopamine function—dopamine transporter and D2 receptors—was significantly associated with the learning rate. We found that this was also the case with COMT, but not for other dopaminergic genes. Together, these findings highlight dissociable roles of frontostriatal systems in strategic learning and support the notion that genetic variation, organized along specific pathways, forms an important source of variation in complex phenotypes such as strategic behavior. PMID:24979760

Dissociable contribution of prefrontal and striatal dopaminergic genes to learning in economic games.

PubMed

Set, Eric; Saez, Ignacio; Zhu, Lusha; Houser, Daniel E; Myung, Noah; Zhong, Songfa; Ebstein, Richard P; Chew, Soo Hong; Hsu, Ming

2014-07-01

Game theory describes strategic interactions where success of players' actions depends on those of coplayers. In humans, substantial progress has been made at the neural level in characterizing the dopaminergic and frontostriatal mechanisms mediating such behavior. Here we combined computational modeling of strategic learning with a pathway approach to characterize association of strategic behavior with variations in the dopamine pathway. Specifically, using gene-set analysis, we systematically examined contribution of different dopamine genes to variation in a multistrategy competitive game captured by (i) the degree players anticipate and respond to actions of others (belief learning) and (ii) the speed with which such adaptations take place (learning rate). We found that variation in genes that primarily regulate prefrontal dopamine clearance--catechol-O-methyl transferase (COMT) and two isoforms of monoamine oxidase--modulated degree of belief learning across individuals. In contrast, we did not find significant association for other genes in the dopamine pathway. Furthermore, variation in genes that primarily regulate striatal dopamine function--dopamine transporter and D2 receptors--was significantly associated with the learning rate. We found that this was also the case with COMT, but not for other dopaminergic genes. Together, these findings highlight dissociable roles of frontostriatal systems in strategic learning and support the notion that genetic variation, organized along specific pathways, forms an important source of variation in complex phenotypes such as strategic behavior.

A clinical genetic method to identify mechanisms by which pain causes depression and anxiety

PubMed Central

Max, Mitchell B; Wu, Tianxia; Atlas, Steven J; Edwards, Robert R; Haythornthwaite, Jennifer A; Bollettino, Antonella F; Hipp, Heather S; McKnight, Colin D; Osman, Inge A; Crawford, Erin N; Pao, Maryland; Nejim, Jemiel; Kingman, Albert; Aisen, Daniel C; Scully, Michele A; Keller, Robert B; Goldman, David; Belfer, Inna

2006-01-01

Background Pain patients are often depressed and anxious, and benefit less from psychotropic drugs than pain-free patients. We hypothesize that this partial resistance is due to the unique neurochemical contribution to mood by afferent pain projections through the spino-parabrachial-hypothalamic-amygdalar systems and their projections to other mood-mediating systems. New psychotropic drugs for pain patients might target molecules in such brain systems. We propose a method to prioritize molecular targets by studying polymorphic genes in cohorts of patients undergoing surgical procedures associated with a variable pain relief response. We seek molecules that show a significant statistical interaction between (1) the amount of surgical pain relief, and (2) the alleles of the gene, on depression and anxiety during the first postoperative year. Results We collected DNA from 280 patients with sciatica due to a lumbar disc herniation, 162 treated surgically and 118 non-surgically, who had been followed for 10 years in the Maine Lumbar Spine Study, a large, prospective, observational study. In patients whose pain was reduced >25% by surgery, symptoms of depression and anxiety, assessed with the SF-36 Mental Health Scale, improved briskly at the first postoperative measurement. In patients with little or no surgical pain reduction, mood scores stayed about the same on average. There was large inter-individual variability at each level of residual pain. Polymorphisms in three pre-specified pain-mood candidate genes, catechol-O-methyl transferase (COMT), serotonin transporter, and brain-derived neurotrophic factor (BDNF) were not associated with late postoperative mood or with a pain-gene interaction on mood. Although the sample size did not provide enough power to persuasively search through a larger number of genes, an exploratory survey of 25 other genes provides illustrations of pain-gene interactions on postoperative mood – the mu opioid receptor for short-term effects of acute sciatica on mood, and the galanin-2 receptor for effects of unrelieved post-discectomy pain on mood one year after surgery. Conclusion Genomic analysis of longitudinal studies of pain, depression, and anxiety in patients undergoing pain-relieving surgery may help to identify molecules through which pain alters mood. Detection of alleles with modest-sized effects will require larger cohorts. PMID:16623937

Modification of Monolignol Biosynthetic Pathway in Jute: Different Gene, Different Consequence

PubMed Central

Shafrin, Farhana; Ferdous, Ahlan Sabah; Sarkar, Suprovath Kumar; Ahmed, Rajib; Amin, Al-; Hossain, Kawsar; Sarker, Mrinmoy; Rencoret, Jorge; Gutiérrez, Ana; del Rio, Jose C.; Sanan-Mishra, Neeti; Khan, Haseena

2017-01-01

Lignin, a cross-linked macromolecule of hydrophobic aromatic structure, provides additional rigidity to a plant cell wall. Although it is an integral part of the plant cell, presence of lignin considerably reduces the quality of the fiber of fiber-yielding plants. Decreasing lignin in such plants holds significant commercial and environmental potential. This study aimed at reducing the lignin content in jute-a fiber crop, by introducing hpRNA-based vectors for downregulation of two monolignoid biosynthetic genes- cinnamate 4-hydroxylase (C4H) and caffeic acid O-methyltransferase (COMT). Transgenic generations, analyzed through Southern, RT-PCR and northern assays showed downregulation of the selected genes. Transgenic lines exhibited reduced level of gene expression with ~ 16–25% reduction in acid insoluble lignin for the whole stem and ~13–14% reduction in fiber lignin content compared to the control lines. Among the two transgenic plant types one exhibited an increase in cellulose content and concomitant improvement of glucose release. Composition of the lignin building blocks was found to alter and this alteration resulted in a pattern, different from other plants where the same genes were manipulated. It is expected that successful COMT-hpRNA and C4H-hpRNA transgenesis in jute will have far-reaching commercial implications leading to product diversification and value addition. PMID:28051165

The association between COMT rs4680 and 5-HTTLPR genotypes and concussion history in South African rugby union players.

PubMed

Mc Fie, Sarah; Abrahams, Shameemah; Patricios, Jon; Suter, Jason; Posthumus, Michael; September, Alison V

2018-04-01

The objective was to investigate the relationship between Catechol-O-methyltransferase (COMT) rs4680 and serotonin-transporter-linked polymorphic region (5-HTTLPR) genotypes with concussion history and personality traits. Rugby players ("all levels": n = 303), from high schools ("junior", n = 137), senior amateur, and professional teams ("senior", n = 166), completed a self-reported concussion history questionnaire, Cloninger's Tridimensional Personality Questionnaire, and donated a DNA sample. Participants were allocated into control (non-concussed, n = 140), case (all) (previous suspected or diagnosed concussions, n = 163), or case (diagnosed only) (previous diagnosed concussion, n = 140) groups. COMT rs4680 Val/Val genotypes were over-represented in controls in all levels (P = 0.013, OR:2.00, 95% CI:1.15-3.57) and in juniors (P = 0.003, OR:3.57, 95% CI:1.45-9.09). Junior Val/Val participants displayed increased "anticipatory worry" (P = 0.023). The 5-HTTLPR low expressing group was under-represented in controls when all levels were considered (P = 0.032; OR:2.02, 95% CI:1.05-3.90) and in juniors (P = 0.021; OR:3.36, 95% CI:1.16-9.72). Junior 5-HTTLPR low and intermediate expressing groups displayed decreased "harm avoidance" (P = 0.009), "anticipatory worry" (P = 0.041), and "fear of uncertainty" (P < 0.001). This study provides preliminary indications that personality associated genetic variants can influence concussion in rugby.

Dopaminergic, Serotonergic, and Oxytonergic Candidate Genes Associated with Infant Attachment Security and Disorganization? In Search of Main and Interaction Effects

ERIC Educational Resources Information Center

Luijk, Maartje P. C. M.; Roisman, Glenn I.; Haltigan, John D.; Tiemeier, Henning; Booth-LaForce, Cathryn; van IJzendoorn, Marinus H.; Belsky, Jay; Uitterlinden, Andre G.; Jaddoe, Vincent W. V.; Hofman, Albert; Verhulst, Frank C.; Tharner, Anne; Bakermans-Kranenburg, Marian J.

2011-01-01

Background and methods: In two birth cohort studies with genetic, sensitive parenting, and attachment data of more than 1,000 infants in total, we tested main and interaction effects of candidate genes involved in the dopamine, serotonin, and oxytocin systems ("DRD4", "DRD2", "COMT", "5-HTT", "OXTR") on attachment security and disorganization.…

Genetic Variants Within Molecular Targets of Antipsychotic Treatment: Effects on Treatment Response, Schizophrenia Risk, and Psychopathological Features.

PubMed

Calabrò, Marco; Porcelli, Stefano; Crisafulli, Concetta; Wang, Sheng-Min; Lee, Soo-Jung; Han, Changsu; Patkar, Ashwin A; Masand, Prakash S; Albani, Diego; Raimondi, Ilaria; Forloni, Gianluigi; Bin, Sofia; Cristalli, Carlotta; Mantovani, Vilma; Pae, Chi-Un; Serretti, Alessandro

2018-01-01

Schizophrenia (SCZ) is a common and severe mental disorder. Genetic factors likely play a role in its pathophysiology as well as in treatment response. In the present study, we investigated the effects of several single nucleotide polymorphisms (SNPs) within 9 genes involved with antipsychotic (AP) mechanisms of action. Two independent samples were recruited. The Korean sample included 176 subjects diagnosed with SCZ and 326 healthy controls, while the Italian sample included 83 subjects and 194 controls. AP response as measured by the positive and negative syndrome scale (PANSS) was the primary outcome, while the secondary outcome was the SCZ risk. Exploratory analyses were performed on (1) symptom clusters response (as measured by PANSS subscales); (2) age of onset; (3) family history; and (4) suicide history. Associations evidenced in the primary analyses did not survive to the FDR correction. Concerning SCZ risk, we partially confirmed the associations among COMT and MAPK1 genetic variants and SCZ. Finally, our exploratory analysis suggested that CHRNA7 and HTR2A genes may modulate both positive and negative symptoms responses, while PLA2G4A and SIGMAR1 may modulate respectively positive and negative symptoms responses. Moreover, GSK3B, HTR2A, PLA2G4A, and S100B variants may determine an anticipation of SCZ age of onset. Our results did not support a primary role for the genes investigated in AP response as a whole. However, our exploratory findings suggested that these genes may be involved in symptom clusters response.

A MYB/ZML Complex Regulates Wound-Induced Lignin Genes in Maize

PubMed Central

Vélez-Bermúdez, Isabel-Cristina; Salazar-Henao, Jorge E.; Franco-Zorrilla, José-Manuel; Grotewold, Erich; Solano, Roberto

2015-01-01

Lignin is an essential polymer in vascular plants that plays key structural roles in vessels and fibers. Lignification is induced by external inputs such as wounding, but the molecular mechanisms that link this stress to lignification remain largely unknown. In this work, we provide evidence that three maize (Zea mays) lignin repressors, MYB11, MYB31, and MYB42, participate in wound-induced lignification by interacting with ZML2, a protein belonging to the TIFY family. We determined that the three R2R3-MYB factors and ZML2 bind in vivo to AC-rich and GAT(A/C) cis-elements, respectively, present in a set of lignin genes. In particular, we show that MYB11 and ZML2 bind simultaneously to the AC-rich and GAT(A/C) cis-elements present in the promoter of the caffeic acid O-methyl transferase (comt) gene. We show that, like the R2R3-MYB factors, ZML2 also acts as a transcriptional repressor. We found that upon wounding and methyl jasmonate treatments, MYB11 and ZML2 proteins are degraded and comt transcription is induced. Based on these results, we propose a molecular regulatory mechanism involving a MYB/ZML complex in which wound-induced lignification can be achieved by the derepression of a set of lignin genes. PMID:26566917

Age differences in arterial and venous extra-cerebral blood flow in healthy adults: contributions of vascular risk factors and genetic variants.

PubMed

Raz, Naftali; Daugherty, Ana M; Sethi, Sean K; Arshad, Muzamil; Haacke, E Mark

2017-08-01

Sufficient cerebral blood flow (CBF) and venous drainage are critical for normal brain function, and their alterations can affect brain aging. However, to date, most studies focused on arterial CBF (inflow) with little attention paid to the age differences in venous outflow. We measured extra-cerebral arterial and venous blood flow rates with phase-contrast MRI and assessed the influence of vascular risk factors and genetic polymorphisms (ACE insertion/deletion, COMT val158met, and APOEε4) in 73 adults (age 18-74 years). Advanced age, elevated vascular risk, ACE Deletion, and COMT met alleles were linked to lower in- and outflow, with no effects of APOE ε4 noted. Lower age-related CBF rate was unrelated to brain volume and was observed only in val homozygotes of COMTval158met. Thus, in a disease-free population, age differences in CBF may be notable only in persons with high vascular risk and carriers of genetic variants associated with vasoconstriction and lower dopamine availability. It remains to be established if treatments targeting alleviation of the mutable factors can improve the course of cerebrovascular aging in spite of the immutable genetic influence.

Convergent functional genomics of schizophrenia: from comprehensive understanding to genetic risk prediction

PubMed Central

Ayalew, M; Le-Niculescu, H; Levey, D F; Jain, N; Changala, B; Patel, S D; Winiger, E; Breier, A; Shekhar, A; Amdur, R; Koller, D; Nurnberger, J I; Corvin, A; Geyer, M; Tsuang, M T; Salomon, D; Schork, N J; Fanous, A H; O'Donovan, M C; Niculescu, A B

2012-01-01

We have used a translational convergent functional genomics (CFG) approach to identify and prioritize genes involved in schizophrenia, by gene-level integration of genome-wide association study data with other genetic and gene expression studies in humans and animal models. Using this polyevidence scoring and pathway analyses, we identify top genes (DISC1, TCF4, MBP, MOBP, NCAM1, NRCAM, NDUFV2, RAB18, as well as ADCYAP1, BDNF, CNR1, COMT, DRD2, DTNBP1, GAD1, GRIA1, GRIN2B, HTR2A, NRG1, RELN, SNAP-25, TNIK), brain development, myelination, cell adhesion, glutamate receptor signaling, G-protein–coupled receptor signaling and cAMP-mediated signaling as key to pathophysiology and as targets for therapeutic intervention. Overall, the data are consistent with a model of disrupted connectivity in schizophrenia, resulting from the effects of neurodevelopmental environmental stress on a background of genetic vulnerability. In addition, we show how the top candidate genes identified by CFG can be used to generate a genetic risk prediction score (GRPS) to aid schizophrenia diagnostics, with predictive ability in independent cohorts. The GRPS also differentiates classic age of onset schizophrenia from early onset and late-onset disease. We also show, in three independent cohorts, two European American and one African American, increasing overlap, reproducibility and consistency of findings from single-nucleotide polymorphisms to genes, then genes prioritized by CFG, and ultimately at the level of biological pathways and mechanisms. Finally, we compared our top candidate genes for schizophrenia from this analysis with top candidate genes for bipolar disorder and anxiety disorders from previous CFG analyses conducted by us, as well as findings from the fields of autism and Alzheimer. Overall, our work maps the genomic and biological landscape for schizophrenia, providing leads towards a better understanding of illness, diagnostics and therapeutics. It also reveals the significant genetic overlap with other major psychiatric disorder domains, suggesting the need for improved nosology. PMID:22584867

Conscientiousness is modified by genetic variation in catechol-O-methyltransferase to reduce symptom complaints in IBS patients.

PubMed

Hall, Kathryn T; Tolkin, Benjamin R; Chinn, Garrett M; Kirsch, Irving; Kelley, John M; Lembo, Anthony J; Kaptchuk, Ted J; Kokkotou, Efi; Davis, Roger B; Conboy, Lisa A

2015-01-01

Attention to and perception of physical sensations and somatic states can significantly influence reporting of complaints and symptoms in the context of clinical care and randomized trials. Although anxiety and high neuroticism are known to increase the frequency and severity of complaints, it is not known if other personality dimensions or genes associated with cognitive function or sympathetic tone can influence complaints. Genetic variation in catechol-O-methyltransferase (COMT) is associated with anxiety, personality, pain, and response to placebo treatment. We hypothesized that the association of complaint reporting with personality might be modified by variation in the COMT val158met genotype. We administered a standard 25-item complaint survey weekly over 3-weeks to a convenience sample of 187 irritable bowel syndrome patients enrolled in a placebo intervention trial and conducted a repeated measures analysis. We found that complaint severity rating, our primary outcome, was negatively associated with the personality measures of conscientiousness (β = -0.31 SE 0.11, P = 0.003) and agreeableness (β = -0.38 SE 0.12, P = 0.002) and was positively associated with neuroticism (β = 0.24 SE 0.09, P = 0.005) and anxiety (β = 0.48 SE 0.09, P < 0.0001). We also found a significant interaction effect of COMT met alleles (β = -32.5 SE 14.1, P = 0.021). in patients genotyped for COMT val158met (N  = 87) specifically COMT × conscientiousness (β = 0.73 SE 0.26, P = 0.0042) and COMT × anxiety (β = -0.42 SE 0.16, P = 0.0078) interaction effects. These findings potentially broaden our understanding of the factors underlying clinical complaints to include the personality dimension of conscientiousness and its modification by COMT.

The dopamine-related polymorphisms BDNF, COMT, DRD2, DRD3, and DRD4 are not linked with changes in CSF dopamine levels and frequency of HIV infection.

PubMed

Horn, Anne; Scheller, C; du Plessis, S; Burger, R; Arendt, G; Joska, J; Sopper, S; Maschke, C M; Obermann, M; Husstedt, I W; Hain, J; Riederer, P; Koutsilieri, E

2017-04-01

We showed previously that higher levels in CSF dopamine in HIV patients are associated with the presence of the dopamine transporter (DAT) 10/10-repeat allele which was also detected more frequently in HIV-infected individuals compared to uninfected subjects. In the current study, we investigated further whether other genetic dopamine (DA)-related polymorphisms may be related with changes in CSF DA levels and frequency of HIV infection in HIV-infected subjects. Specifically, we studied genetic polymorphisms of brain-derived neurotrophic factor, catechol-O-methyltransferase, and dopamine receptors DRD2, DRD3, and DRD4 genetic polymorphisms in uninfected and HIV-infected people in two different ethnical groups, a German cohort (Caucasian, 72 individuals with HIV infection and 22 individuals without HIV infection) and a South African cohort (Xhosan, 54 individuals with HIV infection and 19 individuals without HIV infection). We correlated the polymorphisms with CSF DA levels, HIV dementia score, CD4 + T cell counts, and HIV viral load. None of the investigated DA-related polymorphisms was associated with altered CSF DA levels, CD4 + T cell count, viral load, and HIV dementia score. The respective allele frequencies were equally distributed between HIV-infected patients and controls. Our findings do not show any influence of the studied genetic polymorphisms on CSF DA levels and HIV infection. This is in contrast to what we found previously for the DAT 3'UTR VNTR and highlights the specific role of the DAT VNTR in HIV infection and disease.

Racial and Ethnic Differences in the Pathogenesis and Clinical Manifestations of Uterine Leiomyoma

PubMed Central

Catherino, William H.; Eltoukhi, Heba M.; Al-Hendy, Ayman

2014-01-01

Uterine leiomyomas are the most common benign gynecologic condition. The prevalence is three times more common among women of African ethnicity. Disparity in this disease is evidenced by earlier age of onset, greater severity of symptoms, and different response to treatment. Although the pathogenesis of disease development is not completely known, growing evidence focuses on investigating the molecular mechanisms in disease development and the influence of ethnicity. Variation in the expression levels or function of estrogen and progesterone receptors, polymorphism of genes involved in estrogen synthesis and/or metabolism (COMT, CYP17), retinoic acid nuclear receptors (retinoid acid receptor-α, retinoid X receptor-α), and aberrant expression of micro-RNAs (miRNAs) are some of the molecular mechanisms that may be involved. Nutritional factors, such as vitamin D deficiency, might also contribute to the higher incidence in dark skinned populations who are also commonly suffer from hypovitaminosis D. Culture and environmental difference might have a role in disease development. Further analysis and better understanding of these mechanisms will provide insight into the molecular basis of racial disparities in leiomyoma formation and will help to develop new innovations in leiomyoma treatment. PMID:23934698

Hoarding in obsessive-compulsive disorder: clinical and genetic correlates.

PubMed

Lochner, Christine; Kinnear, Craig J; Hemmings, Sian M J; Seller, Cathlene; Niehaus, Dana J H; Knowles, James A; Daniels, Willie; Moolman-Smook, Johanna C; Seedat, Soraya; Stein, Dan J

2005-09-01

Hoarding may be an important symptom dimension in obsessive-compulsive disorder (OCD). Hoarding in OCD has been associated with poor insight, poorer response to selective serotonin reuptake inhibitors than other OCD symptom dimensions, and a distinctive psychobiological profile. The clinical and genetic correlates of hoarding in OCD therefore deserve additional investigation. Adult OCD patients (N = 315) underwent a comprehensive clinical assessment that included the Structured Clinical Interview for DSM-IV Axis I Disorders (Patient Edition) and for Diagnosis of Obsessive-Compulsive Spectrum Disorders. DNA extracted from venous blood (10-30 mL) in a Caucasian subset of the interviewed OCD patients (N = 204) and Caucasian controls (N = 169), including patients (N = 94) and controls (N = 138) of Afrikaner descent, was genotyped to investigate polymorphisms in genes involved in monoamine function and previously hypothesized to be relevant to OCD. Data were collected from 1998 through 2004. OCD patients with hoarding made up 18.1% of the total sample. Compared with nonhoarding OCD, OCD with hoarding was associated with a number of comorbid Axis I disorders, obsessive-compulsive personality disorder, significantly higher OCD severity scores, and more functional impairment. In subjects of Afrikaner descent, the L/L genotype of the COMT Val158Met polymorphism was significantly more common in the OCD hoarding group, with a preponderance of low activity alleles, compared with nonhoarding patients and controls. These data are consistent with the hypothesis that hoarding represents a unique symptom subtype in OCD with a distinctive clinical and psychobiological profile. Further work is needed to determine the psychobiological mechanisms responsible for hoarding and to replicate the genetic findings noted here.

Associations Between Neurotransmitter Genes and Fatigue and Energy Levels in Women Following Breast Cancer Surgery

PubMed Central

Eshragh, Jasmine; Dhruva, Anand; Paul, Steven M.; Cooper, Bruce A.; Mastick, Judy; Hamolsky, Deborah; Levine, Jon D.; Miaskowski, Christine; Kober, Kord M.

2016-01-01

Context Fatigue is a common problem in oncology patients. Less is known about decrements in energy levels and the mechanisms that underlie both fatigue and energy. Objectives In patients with breast cancer, variations in neurotransmitter genes between Lower and Higher Fatigue latent classes and between the Higher and Lower Energy latent classes were evaluated. Methods Patients completed assessments prior to and monthly for 6 months following surgery. Growth mixture modeling was used to identify distinct latent classes for fatigue severity and energy levels. Thirty candidate genes involved in various aspects of neurotransmission were evaluated. Results Eleven single nucleotide polymorphisms (SNPs) or haplotypes (i.e., ADRB2 rs1042718, BDNF rs6265, COMT rs9332377, CYP3A4 rs4646437, GALR1 rs949060, GCH1 rs3783642, NOS1 rs9658498, NOS1 rs2293052, NPY1R Haplotype A04, SLC6A2 rs17841327 and 5HTTLPR + rs25531 in SLC6A4) were associated with latent class membership for fatigue. Seven SNPs or haplotypes (i.e., NOS1 rs471871, SLC6A1 rs2675163, SLC6A1 Haplotype D01, SLC6A2 rs36027, SLC6A3 rs37022, SLC6A4 rs2020942, and TAC1 rs2072100) were associated with latent class membership for energy. Three of thirteen genes (i.e., NOS1, SLC6A2, SLC6A4) were associated with latent class membership for both fatigue and energy. Conclusions Molecular findings support the hypothesis that fatigue and energy are distinct, yet related symptoms. Results suggest that a large number of neurotransmitters play a role in the development and maintenance of fatigue and energy levels in breast cancer patients. PMID:27720787

Green tea extract and catechol-O-methyltransferase genotype modify the postprandial serum insulin response in a randomised trial of overweight and obese postmenopausal women

PubMed Central

Dostal, Allison M.; Arikawa, Andrea; Espejo, Luis; Bedell, Sarah; Kurzer, Mindy S.; Stendell-Hollis, Nicole R.

2016-01-01

Background Green tea extract (GTE) may be involved in a favorable postprandial response to high-carbohydrate meals. Catechol-O-methyltransferase (COMT) genotype may modify these effects. We examined the acute effects of GTE supplementation on postprandial response to a high-carbohydrate meal through assessing appetite-associated hormones and glucose homeostasis marker concentrations in women who consumed 843 mg (−)-epigallocatechin-3-gallate [EGCG]) or placebo capsules for 11-12 months. Methods Sixty Caucasian postmenopausal women (BMI ≥ 25.0 kg/m2) were included in a randomized, double-blind feeding study. GTE was consumed with a breakfast meal (665.4 kcal; 67.2% carbohydrate). Blood samples were drawn pre-meal, post-meal, and every 30 minutes for 4 h. Participants completed six satiety questionnaires. Results Plasma leptin, ghrelin, and adiponectin did not differ between GTE and placebo at any time point; COMT genotype did not modify these results. Participants randomized to GTE with the high-activity form of COMT (GTE-high COMT) had higher insulin concentrations at time 0, 0.5, and 1.0 h post-meal compared to all COMT groups randomized to placebo. Insulin remained higher in the GTE-high COMT group at 1.5, 2.0, and 2.5 h compared to Placebo-low COMT (P < 0.02). GTE-high COMT had higher insulin concentrations at times 0, 0.5, 1.0, 1.5, and 2.0 h compared to the GTE-low COMT (P ≤ 0.04). AUC measurements of satiety did not differ between GTE and placebo. Conclusions GTE supplementation and COMT genotype did not alter acute postprandial responses of leptin, ghrelin, adiponectin, or satiety, but may be involved in post-meal insulinemic response of overweight and obese postmenopausal women. PMID:27600055

A single- and multiple-dose study to investigate the pharmacokinetics and pharmacodynamics of opicapone, a novel COMT inhibitor, in rat.

PubMed

Gonçalves, Daniela; Alves, Gilberto; Fortuna, Ana; Bonifácio, Maria João; Soares-da-Silva, Patrício; Falcão, Amílcar

2017-10-01

Opicapone is a novel catechol-O-methyltransferase (COMT) inhibitor that emerged to fulfil the need of a safer and more efficacious COMT inhibitor. The present study was carried out in order to assess and compare the pharmacokinetics and pharmacodynamics (COMT inhibition) of opicapone after single and multiple oral administrations (30 mg/kg) to Wistar rats. For this purpose, at predefined time points up to 72 h post-dosing, blood, liver and kidneys were collected and, then, the concentrations of opicapone and its active metabolite (BIA 9-1079) were determined in plasma and in liver and kidney tissues, as well as the erythrocyte, liver and kidney COMT activity. No systemic, renal or hepatic accumulation of opicapone was observed following repeated administration. Furthermore, the tissue-systemic exposure relationships to opicapone suggested a low drug exposure in the liver and kidneys. After single-dosing, COMT inhibition profiles were reasonably comparable in all the studied matrices; although similar results were found after multiple-dosing, a higher degree of inhibition was observed, indicating a continuous peripheral COMT inhibition when opicapone is administered once-daily. Despite having a short elimination half-life (≤2.94 h), opicapone showed a strong and long-lasting COMT inhibition in both studies, since more than 50% of the COMT activity was still inhibited at 24 h post-dosing. Copyright © 2017 Elsevier Ltd. All rights reserved.

A MYB/ZML Complex Regulates Wound-Induced Lignin Genes in Maize.

PubMed

Vélez-Bermúdez, Isabel-Cristina; Salazar-Henao, Jorge E; Fornalé, Silvia; López-Vidriero, Irene; Franco-Zorrilla, José-Manuel; Grotewold, Erich; Gray, John; Solano, Roberto; Schmidt, Wolfgang; Pagés, Montserrat; Riera, Marta; Caparros-Ruiz, David

2015-11-01

Lignin is an essential polymer in vascular plants that plays key structural roles in vessels and fibers. Lignification is induced by external inputs such as wounding, but the molecular mechanisms that link this stress to lignification remain largely unknown. In this work, we provide evidence that three maize (Zea mays) lignin repressors, MYB11, MYB31, and MYB42, participate in wound-induced lignification by interacting with ZML2, a protein belonging to the TIFY family. We determined that the three R2R3-MYB factors and ZML2 bind in vivo to AC-rich and GAT(A/C) cis-elements, respectively, present in a set of lignin genes. In particular, we show that MYB11 and ZML2 bind simultaneously to the AC-rich and GAT(A/C) cis-elements present in the promoter of the caffeic acid O-methyl transferase (comt) gene. We show that, like the R2R3-MYB factors, ZML2 also acts as a transcriptional repressor. We found that upon wounding and methyl jasmonate treatments, MYB11 and ZML2 proteins are degraded and comt transcription is induced. Based on these results, we propose a molecular regulatory mechanism involving a MYB/ZML complex in which wound-induced lignification can be achieved by the derepression of a set of lignin genes. © 2015 American Society of Plant Biologists. All rights reserved.

Individual Differences in the Speed of Facial Emotion Recognition Show Little Specificity but Are Strongly Related with General Mental Speed: Psychometric, Neural and Genetic Evidence

PubMed Central

Liu, Xinyang; Hildebrandt, Andrea; Recio, Guillermo; Sommer, Werner; Cai, Xinxia; Wilhelm, Oliver

2017-01-01

Facial identity and facial expression processing are crucial socio-emotional abilities but seem to show only limited psychometric uniqueness when the processing speed is considered in easy tasks. We applied a comprehensive measurement of processing speed and contrasted performance specificity in socio-emotional, social and non-social stimuli from an individual differences perspective. Performance in a multivariate task battery could be best modeled by a general speed factor and a first-order factor capturing some specific variance due to processing emotional facial expressions. We further tested equivalence of the relationships between speed factors and polymorphisms of dopamine and serotonin transporter genes. Results show that the speed factors are not only psychometrically equivalent but invariant in their relation with the Catechol-O-Methyl-Transferase (COMT) Val158Met polymorphism. However, the 5-HTTLPR/rs25531 serotonin polymorphism was related with the first-order factor of emotion perception speed, suggesting a specific genetic correlate of processing emotions. We further investigated the relationship between several components of event-related brain potentials with psychometric abilities, and tested emotion specific individual differences at the neurophysiological level. Results revealed swifter emotion perception abilities to go along with larger amplitudes of the P100 and the Early Posterior Negativity (EPN), when emotion processing was modeled on its own. However, after partialling out the shared variance of emotion perception speed with general processing speed-related abilities, brain-behavior relationships did not remain specific for emotion. Together, the present results suggest that speed abilities are strongly interrelated but show some specificity for emotion processing speed at the psychometric level. At both genetic and neurophysiological levels, emotion specificity depended on whether general cognition is taken into account or not. These findings keenly suggest that general speed abilities should be taken into account when the study of emotion recognition abilities is targeted in its specificity. PMID:28848411

The Nature of War Theory

DTIC Science & Technology

2011-03-10

of Positivism, 1848, Auguste Comte presents the Hierarchy of Science that is in general use today. Mathematics is at the top of Comte ‟s hierarchy of...sciences, followed by physics, chemistry, biology, and finally, sociology. In Comte ‟s hierarchy, the complete understanding of a given science...von Clausewitz, Henri Jomini, and the other 19th Century scholars of war who may have been familiar with Comte ‟s writings. What these scholars of war

Genetic contribution of catechol-O-methyltransferase polymorphism (Val158Met) in children with chronic tension-type headache.

PubMed

Fernández-de-las-Peñas, César; Ambite-Quesada, Silvia; Rivas-Martínez, Inés; Ortega-Santiago, Ricardo; de-la-Llave-Rincón, Ana Isabel; Fernández-Mayoralas, Daniel M; Pareja, Juan A

2011-10-01

Our aim was to investigate the relationship between Val158Met polymorphisms, headache, and pressure hypersensitivity in children with chronic tension-type headache (CTTH). A case-control study with blinded assessor was conducted. Seventy children with CTTH associated with pericranial tenderness and 70 healthy children participated. After amplifying Val158Met polymorphism by polymerase chain reactions, we assessed genotype frequencies and allele distributions. We classified children according to their Val158Met polymorphism: Val/Val, Val/Met, Met/Met. Pressure pain thresholds (PPT) were bilaterally assessed over the temporalis, upper trapezius, second metacarpal, and tibialis anterior muscles. The distribution of Val158Met genotypes was not significantly different (p = 0.335), between children with CTTH and healthy children, and between boys and girls (p = 0.872). Children with CTTH with the Met/Met genotype showed a longer headache history compared with those with Met/Val (p = 0.001) or Val/Val (p = 0.002) genotype. Children with CTTH with Met/Met genotype showed lower PPT over upper trapezius and temporalis muscles than children with CTTH with Met/Val or Val/Val genotype (p < 0.01). The Val158Met catechol-O-methyltransferase (COMT) polymorphism does not appear to be involved in predisposition to suffer from CTTH in children; nevertheless, this genetic factor may be involved in the phenotypic expression, as pressure hypersensitivity was greater in those CTTH children with the Met/Met genotype.

Accumulation of Phenolic Compounds and Expression Profiles of Phenolic Acid Biosynthesis-Related Genes in Developing Grains of White, Purple, and Red Wheat.

PubMed

Ma, Dongyun; Li, Yaoguang; Zhang, Jian; Wang, Chenyang; Qin, Haixia; Ding, Huina; Xie, Yingxin; Guo, Tiancai

2016-01-01

Polyphenols in whole grain wheat have potential health benefits, but little is known about the expression patterns of phenolic acid biosynthesis genes and the accumulation of phenolic acid compounds in different-colored wheat grains. We found that purple wheat varieties had the highest total phenolic content (TPC) and antioxidant activity. Among phenolic acid compounds, bound ferulic acid, vanillic, and caffeic acid levels were significantly higher in purple wheat than in white and red wheat, while total soluble phenolic acid, soluble ferulic acid, and vanillic acid levels were significantly higher in purple and red wheat than in white wheat. Ferulic acid and syringic acid levels peaked at 14 days after anthesis (DAA), whereas p-coumaric acid and caffeic acid levels peaked at 7 DAA, and vanillic acid levels gradually increased during grain filling and peaked near ripeness (35 DAA). Nine phenolic acid biosynthesis pathway genes (TaPAL1, TaPAL2, TaC3H1, TaC3H2, TaC4H, Ta4CL1, Ta4CL2, TaCOMT1, and TaCOMT2) exhibited three distinct expression patterns during grain filling, which may be related to the different phenolic acids levels. White wheat had higher phenolic acid contents and relatively high gene expression at the early stage, while purple wheat had the highest phenolic acid contents and gene expression levels at later stages. These results suggest that the expression of phenolic acid biosynthesis genes may be closely related to phenolic acids accumulation.

Accumulation of Phenolic Compounds and Expression Profiles of Phenolic Acid Biosynthesis-Related Genes in Developing Grains of White, Purple, and Red Wheat

PubMed Central

Ma, Dongyun; Li, Yaoguang; Zhang, Jian; Wang, Chenyang; Qin, Haixia; Ding, Huina; Xie, Yingxin; Guo, Tiancai

2016-01-01

Polyphenols in whole grain wheat have potential health benefits, but little is known about the expression patterns of phenolic acid biosynthesis genes and the accumulation of phenolic acid compounds in different-colored wheat grains. We found that purple wheat varieties had the highest total phenolic content (TPC) and antioxidant activity. Among phenolic acid compounds, bound ferulic acid, vanillic, and caffeic acid levels were significantly higher in purple wheat than in white and red wheat, while total soluble phenolic acid, soluble ferulic acid, and vanillic acid levels were significantly higher in purple and red wheat than in white wheat. Ferulic acid and syringic acid levels peaked at 14 days after anthesis (DAA), whereas p-coumaric acid and caffeic acid levels peaked at 7 DAA, and vanillic acid levels gradually increased during grain filling and peaked near ripeness (35 DAA). Nine phenolic acid biosynthesis pathway genes (TaPAL1, TaPAL2, TaC3H1, TaC3H2, TaC4H, Ta4CL1, Ta4CL2, TaCOMT1, and TaCOMT2) exhibited three distinct expression patterns during grain filling, which may be related to the different phenolic acids levels. White wheat had higher phenolic acid contents and relatively high gene expression at the early stage, while purple wheat had the highest phenolic acid contents and gene expression levels at later stages. These results suggest that the expression of phenolic acid biosynthesis genes may be closely related to phenolic acids accumulation. PMID:27148345

Melatonin production in Escherichia coli by dual expression of serotonin N-acetyltransferase and caffeic acid O-methyltransferase.

PubMed

Byeon, Yeong; Back, Kyoungwhan

2016-08-01

Melatonin is a well-known bioactive molecule produced in animals and plants and a well-studied natural compound. Two enzymatic steps are required for the biosynthesis of melatonin from serotonin. First, serotonin N-acetyltransferase (SNAT) catalyzes serotonin to N-acetylserotonin (NAS) followed by the action of N-acetylserotonin O-methyltransferase (ASMT), resulting in the synthesis of O-methylated NAS, also known as melatonin. Attempts to document melatonin production in Escherichia coli have been unsuccessful to date due to either low enzyme activity or inactive ASMT expression. Here, we employed caffeic acid O-methyltransferase (COMT) instead of ASMT, as COMT is a multifunctional enzyme that has ASMT activity as well. Among several combinations of dual expression cassettes, recombinant E. coli that expressed sheep SNAT with rice COMT produced a high quantity of melatonin, which was measured in a culture medium (1.46 mg/L in response to 1 mM serotonin). This level was several orders of magnitude higher than that produced in transgenic rice and tomato overexpressing sheep SNAT and ASMT, respectively. This heterologous expression system can be widely employed to screen various putative SNAT or ASMT genes from animals and plants as well as to overproduce melatonin in various useful microorganisms.

Acute effects of cocaine and cannabis on reversal learning as a function of COMT and DRD2 genotype.

PubMed

Spronk, Desirée B; Van der Schaaf, Marieke E; Cools, Roshan; De Bruijn, Ellen R A; Franke, Barbara; van Wel, Janelle H P; Ramaekers, Johannes G; Verkes, Robbert J

2016-01-01

Long-term cannabis and cocaine use has been associated with impairments in reversal learning. However, how acute cannabis and cocaine administration affect reversal learning in humans is not known. In this study, we aimed to establish the acute effects of administration of cannabis and cocaine on valence-dependent reversal learning as a function of DRD2 Taq1A (rs1800497) and COMT Val108/158Met (rs4680) genotype. A double-blind placebo-controlled randomized 3-way crossover design was used. Sixty-one regular poly-drug users completed a deterministic reversal learning task under the influence of cocaine, cannabis, and placebo that enabled assessment of both reward- and punishment-based reversal learning. Proportion correct on the reversal learning task was increased by cocaine, but decreased by cannabis. Effects of cocaine depended on the DRD2 genotype, as increases in proportion correct were seen only in the A1 carriers, and not in the A2/A2 homozygotes. COMT genotype did not modulate drug-induced effects on reversal learning. These data indicate that acute administration of cannabis and cocaine has opposite effects on reversal learning. The effects of cocaine, but not cannabis, depend on interindividual genetic differences in the dopamine D2 receptor gene.

Does lignin modification affect feeding preference or growth performance of insect herbivores in transgenic silver birch (Betula pendula Roth)?

PubMed

Tiimonen, Heidi; Aronen, Tuija; Laakso, Tapio; Saranpää, Pekka; Chiang, Vincent; Ylioja, Tiina; Roininen, Heikki; Häggman, Hely

2005-11-01

Transgenic silver birch (Betula pendula Roth) lines were produced in order to modify lignin biosynthesis. These lines carry COMT (caffeate/5-hydroxyferulate O-methyltransferase) gene from Populus tremuloides driven by constitutive promoter 35S CaMV (cauliflower mosaic virus) or UbB1 (ubiquitin promoter from sunflower). The decreased syringyl/guaiacyl (S/G) ratio was found in stem and leaf lignin of 35S CaMV-PtCOMT transgenic silver birch lines when compared to non-transformed control or UbB1-PtCOMT lines. In controlled feeding experiments the leaves of transgenic birch lines as well as controls were fed to insect herbivores common in boreal environment, i.e., larvae of Aethalura punctulata, Cleora cinctaria and Trichopteryx carpinata (Lepidoptera: Geometridae) as well as the adults of birch leaf-feeding beetles Agelastica alni (Coleoptera: Chrysomelidae) and Phyllobius spp. (Coleoptera: Curculionidae). The feeding preferences of these herbivores differed in some cases among the tested birch lines, but these differences could not be directly associated to lignin modification. They could as well be explained by other characteristics of leaves, either natural or caused by transgene site effects. Growth performance of lepidopteran larvae fed on transgenic or control leaves did not differ significantly.

Influence of Dopamine-Related Genes on Neurobehavioral Recovery after Traumatic Brain Injury during Early Childhood.

PubMed

Treble-Barna, Amery; Wade, Shari L; Martin, Lisa J; Pilipenko, Valentina; Yeates, Keith Owen; Taylor, H Gerry; Kurowski, Brad G

2017-06-01

The present study examined the association of dopamine-related genes with short- and long-term neurobehavioral recovery, as well as neurobehavioral recovery trajectories over time, in children who had sustained early childhood traumatic brain injuries (TBI) relative to children who had sustained orthopedic injuries (OI). Participants were recruited from a prospective, longitudinal study evaluating outcomes of children who sustained a TBI (n = 68) or OI (n = 72) between the ages of 3 and 7 years. Parents completed ratings of child executive function and behavior at the immediate post-acute period (0-3 months after injury); 6, 12, and 18 months after injury; and an average of 3.5 and 7 years after injury. Thirty-two single nucleotide polymorphisms (SNPs) in dopamine-related genes (dopamine receptor D2 [DRD2], solute carrier family 6 member 3 [SLC6A3], solute carrier family 18 member A2 [SLC18A2], catechol-o-methyltransferase [COMT], and ankyrin repeat and kinase domain containing 1 [ANKK1]) were examined in association with short- and long-term executive function and behavioral adjustment, as well as their trajectories over time. After controlling for premorbid child functioning, genetic variation within the SLC6A3 (rs464049 and rs460000) gene was differentially associated with neurobehavioral recovery trajectories over time following TBI relative to OI, with rs464049 surviving multiple testing corrections. In addition, genetic variation within the ANKK1 (rs1800497 and rs2734849) and SLC6A3 (rs464049, rs460000, and rs1042098) genes was differentially associated with short- and long-term neurobehavioral recovery following TBI, with rs460000 and rs464049 surviving multiple testing corrections. The findings provide preliminary evidence that genetic variation in genes involved in DRD2 expression and density (ANKK1) and dopamine transport (SLC6A3) plays a role in neurobehavioral recovery following pediatric TBI.

Schooling and Variation in the "COMT" Gene: The Devil Is in the Details

ERIC Educational Resources Information Center

Campbell, Daniel; Bick, Johanna; Yrigollen, Carolyn M.; Lee, Maria; Joseph, Antony; Chang, Joseph T.; Grigorenko, Elena L.

2013-01-01

Background: Schooling is considered one of the major contributors to the development of intelligence within societies and individuals. Genetic variation might modulate the impact of schooling and explain, at least partially, the presence of individual differences in classrooms. Method: We studied a sample of 1,502 children (mean age = 11.7 years)…

Brain catechol-o-methyltransferase (COMT) inhibition by tolcapone counteracts recognition memory deficits in normal and chronic phencyclidine-treated rats and in COMT-Val transgenic mice

PubMed Central

Detrait, E.R.; Carr, G.V.; Ferraille, S.; Weinberger, D.R.; Lamberty, Y.

2015-01-01

The critical involvement of dopamine in cognitive processes has been well established, suggesting therapies targeting dopamine metabolism may alleviate cognitive dysfunction. COMT is a catecholamine-degrading enzyme, the substrates of which include dopamine, epinephrine, and norepinephrine. The present work illustrates the potential therapeutic efficacy of COMT inhibition for alleviating cognitive impairment. A brain penetrant COMT inhibitor, tolcapone, was tested in normal and phencyclidine (PCP)-treated rats and COMT–Val transgenic mice. In a Novel Object Recognition (NOR) procedure, tolcapone counteracted a 24h-dependent forgetting of a familiar object and counteracted PCP-induced recognition deficits in the rats at doses ranging from 7.5 to 30 mg/kg. In contrast, entacapone, a COMT inhibitor which does not readily cross the blood-brain barrier failed to show efficacy at doses up to 30mg/kg. Tolcapone at a dose of 30 mg/kg also improved NOR performance in the transgenic mice, which showed clear recognition deficits. Complementing earlier studies, our results indicate that central inhibition of COMT positively impacts recognition memory processes and might constitute an appealing treatment for cognitive dysfunction related to neuropsychiatric disorders. PMID:26919286

Study of traits and recalcitrance reduction of field-grown COMT down-regulated switchgrass

DOE PAGES

Li, Mi; Pu, Yunqiao; Yoo, Chang Geun; ...

2017-01-03

The native recalcitrance of plants hinders the biomass conversion process using current biorefinery techniques. Down-regulation of the caffeic acid O-methyltransferase (COMT) gene in the lignin biosynthesis pathway of switchgrass reduced the thermochemical and biochemical conversion recalcitrance of biomass. Due to potential environmental influences on lignin biosynthesis and deposition, studying the consequences of physicochemical changes in field-grown plants without pretreatment is essential to evaluate the performance of lignin-altered plants. In this study, we determined the chemical composition, cellulose crystallinity and the degree of its polymerization, molecular weight of hemicellulose, and cellulose accessibility of cell walls in order to better understand themore » fundamental features of why biomass is recalcitrant to conversion without pretreatment. The most important is to investigate whether traits and features are stable in the dynamics of field environmental effects over multiple years.« less

Innate Immune Signalling Genetics of Pain, Cognitive Dysfunction and Sickness Symptoms in Cancer Pain Patients Treated with Transdermal Fentanyl

PubMed Central

Barratt, Daniel T.; Klepstad, Pål; Dale, Ola; Kaasa, Stein; Somogyi, Andrew A.

2015-01-01

Common adverse symptoms of cancer and chemotherapy are a major health burden; chief among these is pain, with opioids including transdermal fentanyl the mainstay of treatment. Innate immune activation has been implicated generally in pain, opioid analgesia, cognitive dysfunction, and sickness type symptoms reported by cancer patients. We aimed to determine if genetic polymorphisms in neuroimmune activation pathways alter the serum fentanyl concentration-response relationships for pain control, cognitive dysfunction, and other adverse symptoms, in cancer pain patients. Cancer pain patients (468) receiving transdermal fentanyl were genotyped for 31 single nucleotide polymorphisms in 19 genes: CASP1, BDNF, CRP, LY96, IL6, IL1B, TGFB1, TNF, IL10, IL2, TLR2, TLR4, MYD88, IL6R, OPRM1, ARRB2, COMT, STAT6 and ABCB1. Lasso and backward stepwise generalised linear regression were used to identify non-genetic and genetic predictors, respectively, of pain control (average Brief Pain Inventory < 4), cognitive dysfunction (Mini-Mental State Examination ≤ 23), sickness response and opioid adverse event complaint. Serum fentanyl concentrations did not predict between-patient variability in these outcomes, nor did genetic factors predict pain control, sickness response or opioid adverse event complaint. Carriers of the MYD88 rs6853 variant were half as likely to have cognitive dysfunction (11/111) than wild-type patients (69/325), with a relative risk of 0.45 (95% CI: 0.27 to 0.76) when accounting for major non-genetic predictors (age, Karnofsky functional score). This supports the involvement of innate immune signalling in cognitive dysfunction, and identifies MyD88 signalling pathways as a potential focus for predicting and reducing the burden of cognitive dysfunction in cancer pain patients. PMID:26332828

Convergence of genome-wide association and candidate gene studies for alcoholism.

PubMed

Olfson, Emily; Bierut, Laura Jean

2012-12-01

Genome-wide association (GWA) studies have led to a paradigm shift in how researchers study the genetics underlying disease. Many GWA studies are now publicly available and can be used to examine whether or not previously proposed candidate genes are supported by GWA data. This approach is particularly important for the field of alcoholism because the contribution of many candidate genes remains controversial. Using the Human Genome Epidemiology (HuGE) Navigator, we selected candidate genes for alcoholism that have been frequently examined in scientific articles in the past decade. Specific candidate loci as well as all the reported single nucleotide polymorphisms (SNPs) in candidate genes were examined in the Study of Addiction: Genetics and Environment (SAGE), a GWA study comparing alcohol-dependent and nondependent subjects. Several commonly reported candidate loci, including rs1800497 in DRD2, rs698 in ADH1C, rs1799971 in OPRM1, and rs4680 in COMT, are not replicated in SAGE (p > 0.05). Among candidate loci available for analysis, only rs279858 in GABRA2 (p = 0.0052, OR = 1.16) demonstrated a modest association. Examination of all SNPs reported in SAGE in over 50 candidate genes revealed no SNPs with large frequency differences between cases and controls, and the lowest p-value of any SNP was 0.0006. We provide evidence that several extensively studied candidate loci do not have a strong contribution to risk of developing alcohol dependence in European and African ancestry populations. Owing to the lack of coverage, we were unable to rule out the contribution of other variants, and these genes and particular loci warrant further investigation. Our analysis demonstrates that publicly available GWA results can be used to better understand which if any of previously proposed candidate genes contribute to disease. Furthermore, we illustrate how examining the convergence of candidate gene and GWA studies can help elucidate the genetic architecture of alcoholism and more generally complex diseases. Copyright © 2012 by the Research Society on Alcoholism.

Hierarchical prediction errors in midbrain and septum during social learning.

PubMed

Diaconescu, Andreea O; Mathys, Christoph; Weber, Lilian A E; Kasper, Lars; Mauer, Jan; Stephan, Klaas E

2017-04-01

Social learning is fundamental to human interactions, yet its computational and physiological mechanisms are not well understood. One prominent open question concerns the role of neuromodulatory transmitters. We combined fMRI, computational modelling and genetics to address this question in two separate samples (N = 35, N = 47). Participants played a game requiring inference on an adviser's intentions whose motivation to help or mislead changed over time. Our analyses suggest that hierarchically structured belief updates about current advice validity and the adviser's trustworthiness, respectively, depend on different neuromodulatory systems. Low-level prediction errors (PEs) about advice accuracy not only activated regions known to support 'theory of mind', but also the dopaminergic midbrain. Furthermore, PE responses in ventral striatum were influenced by the Met/Val polymorphism of the Catechol-O-Methyltransferase (COMT) gene. By contrast, high-level PEs ('expected uncertainty') about the adviser's fidelity activated the cholinergic septum. These findings, replicated in both samples, have important implications: They suggest that social learning rests on hierarchically related PEs encoded by midbrain and septum activity, respectively, in the same manner as other forms of learning under volatility. Furthermore, these hierarchical PEs may be broadcast by dopaminergic and cholinergic projections to induce plasticity specifically in cortical areas known to represent beliefs about others. © The Author (2017). Published by Oxford University Press.

Hierarchical prediction errors in midbrain and septum during social learning

PubMed Central

Mathys, Christoph; Weber, Lilian A. E.; Kasper, Lars; Mauer, Jan; Stephan, Klaas E.

2017-01-01

Abstract Social learning is fundamental to human interactions, yet its computational and physiological mechanisms are not well understood. One prominent open question concerns the role of neuromodulatory transmitters. We combined fMRI, computational modelling and genetics to address this question in two separate samples (N = 35, N = 47). Participants played a game requiring inference on an adviser’s intentions whose motivation to help or mislead changed over time. Our analyses suggest that hierarchically structured belief updates about current advice validity and the adviser’s trustworthiness, respectively, depend on different neuromodulatory systems. Low-level prediction errors (PEs) about advice accuracy not only activated regions known to support ‘theory of mind’, but also the dopaminergic midbrain. Furthermore, PE responses in ventral striatum were influenced by the Met/Val polymorphism of the Catechol-O-Methyltransferase (COMT) gene. By contrast, high-level PEs (‘expected uncertainty’) about the adviser’s fidelity activated the cholinergic septum. These findings, replicated in both samples, have important implications: They suggest that social learning rests on hierarchically related PEs encoded by midbrain and septum activity, respectively, in the same manner as other forms of learning under volatility. Furthermore, these hierarchical PEs may be broadcast by dopaminergic and cholinergic projections to induce plasticity specifically in cortical areas known to represent beliefs about others. PMID:28119508

Effect of long-term actual spaceflight on the expression of key genes encoding serotonin and dopamine system

NASA Astrophysics Data System (ADS)

Popova, Nina; Shenkman, Boris; Naumenko, Vladimir; Kulikov, Alexander; Kondaurova, Elena; Tsybko, Anton; Kulikova, Elisabeth; Krasnov, I. B.; Bazhenova, Ekaterina; Sinyakova, Nadezhda

The effect of long-term spaceflight on the central nervous system represents important but yet undeveloped problem. The aim of our work was to study the effect of 30-days spaceflight of mice on Russian biosatellite BION-M1 on the expression in the brain regions of key genes of a) serotonin (5-HT) system (main enzymes in 5-HT metabolism - tryptophan hydroxylase-2 (TPH-2), monoamine oxydase A (MAO A), 5-HT1A, 5-HT2A and 5-HT3 receptors); b) pivotal enzymes in DA metabolism (tyrosine hydroxylase, COMT, MAO A, MAO B) and D1, D2 receptors. Decreased expression of genes encoding the 5-HT catabolism (MAO A) and 5-HT2A receptor in some brain regions was shown. There were no differences between “spaceflight” and control mice in the expression of TPH-2 and 5-HT1A, 5-HT3 receptor genes. Significant changes were found in genetic control of DA system. Long-term spaceflight decreased the expression of genes encoding the enzyme in DA synthesis (tyrosine hydroxylase in s.nigra), DA metabolism (MAO B in the midbrain and COMT in the striatum), and D1 receptor in hypothalamus. These data suggested that 1) microgravity affected genetic control of 5-HT and especially the nigrostriatal DA system implicated in the central regulation of muscular tonus and movement, 2) the decrease in the expression of genes encoding key enzyme in DA synthesis, DA degradation and D1 receptor contributes to the movement impairment and dyskinesia produced by the spaceflight. The study was supported by Russian Foundation for Basic Research grant No. 14-04-00173.

The effect of interactions between genetics and cannabis use on neurocognition. A review.

PubMed

Cosker, E; Schwitzer, T; Ramoz, N; Ligier, F; Lalanne, L; Gorwood, P; Schwan, R; Laprévote, V

2018-03-02

Cannabis is one of the most widely-used drugs in industrialized countries. It is now well established that cannabis use impacts neurocognition. In the intoxication period time episodic memory, working memory and attention are impacted and impulsivity is increased. The long-term effects of cannabis use tend to be similar. Various internal factors, such as sex differences, modulate this impact. It is unclear whether genetic variations can also influence the impact of cannabis on neurocognition. We set out to examine the impact of genetic variations on neurocognition in cannabis users. We conducted a search via the PubMed, Web of Science, and ScienceDirect databases to identify studies measuring neurocognition and assessing genotypes in the context of cannabis use. We included 13 articles. We found that working memory, verbal and visual memory and sustained attention are more impacted during intoxication in subjects with the Val COMT allele. COMT gene could also modulate sustained attention in regular use. The CNR1, AKT1, DBH and 5-HTT/SLC6A4 genes may also modulate effects. Most of these genes are linked to schizophrenia. A fuller understanding of their impact on the effects of cannabis on neurocognition would thus help elucidate the mechanisms linking cannabis and psychosis. However, evidence is still scant, and more research is needed. Copyright © 2017. Published by Elsevier Inc.

Expression of estrogenicity genes in a lineage cell culture model of human breast cancer progression

PubMed Central

Fu, Jiaqi; Weise, Amy M.; Falany, Josie L.; Falany, Charles N.; Thibodeau, Bryan J.; Miller, Fred R.; Kocarek, Thomas A.

2013-01-01

TaqMan Gene Expression assays were used to profile the mRNA expression of estrogen receptor (ERα and ERβ) and estrogen metabolism enzymes including cytosolic sulfotransferases (SULT1E1, SULT1A1, SULT2A1, and SULT2B1), steroid sulfatase (STS), aromatase (CYP19), 17β-hydroxysteroid dehydrogenases (17βHSD1 and 2), CYP1B1, and catechol-O-methyltransferase (COMT) in an MCF10A-derived lineage cell culture model for basal-like human breast cancer progression and in ERα-positive luminal MCF7 breast cancer cells. Low levels of ERα and ERβ mRNA were present in MCF10A-derived cell lines. SULT1E1 mRNA was more abundant in confluent relative to subconfluent MCF10A cells, a non-tumorigenic proliferative breast disease cell line. SULT1E1 was also expressed in preneoplastic MCF10AT1 and MCF10AT1K.cl2 cells, but was markedly repressed in neoplastic MCF10A-derived cell lines as well as in MCF7 cells. Steroid-metabolizing enzymes SULT1A1 and SULT2B1 were only expressed in MCF7 cells. STS and COMT were widely detected across cell lines. Pro-estrogenic 17βHSD1 mRNA was most abundant in neoplastic MCF10CA1a and MCF10DCIS.com cells, while 17βHSD2 mRNA was more prominent in parental MCF10A cells. CYP1B1 mRNA was most abundant in MCF7 cells. Treatment with the histone deacetylase inhibitor trichostatin A (TSA) induced SULT1E1 and CYP19 mRNA but suppressed CYP1B1, STS, COMT, 17βHSD1, and 17βHSD2 mRNA in MCF10A lineage cell lines. In MCF7 cells, TSA treatment suppressed ERα, CYP1B1, STS, COMT, SULT1A1, and SULT2B1 but induced ERβ, CYP19 and SULT2A1 mRNA expression. The results indicate that relative to the MCF7 breast cancer cell line, key determinants of breast estrogen metabolism are differentially regulated in the MCF10A-derived lineage model for breast cancer progression. PMID:19308726

[The dentistry of Blainville and the positivism of Comte].

PubMed

Gysel, C

1989-01-01

COMTE improved BLAINVILLE's acquaintance when he was the secretary of SAINT-SIMON. They became friends. BLAINVILLE aided COMTE in his illness and financial troubles, taught him biology and was one of the first to support his philosophical ideas, through which he became self-conscious of his own value and scientific methods.

Exercise-induced changes in enzymatic O-methylation of catecholestrogens by erythrocytes of eumenorrheic women.

PubMed

De Crée, C; Van Kranenburg, G; Geurten, P; Fujimura, Y; Keizer, H A

1997-12-01

The present study was designed to assess the effects of acute exercise and short-term intensive training on catechol-O-methyltransferase (COMT) activity. COMT inactivates catecholamines and converts primary catecholestrogens (CE) into their O-methylated form yielding the 2- (2-MeOE) and 4-methoxyestrogens (4-MeOE). Blood samples were obtained from 15 previously untrained eumenorrheic women (mean +/- SE, VO2max: 43.8 mL x kg-1 x min-1 +/- 0.6) before and after a 5-d intensive training period, at rest and during incremental exercise. COMT activity was determined in the erythrocytes (RBC-COMT) after incubation of blood lysate with primary CE. The formation of both 2- and 4-MeOE was significantly higher (P < 0.05) during the luteal (LPh) than during the follicular phase (FPh). The amount of 2-MeOE formed (FPh: 4.2 +/- 0.2%; LPh: 4.9 +/- 0.2%) was significantly greater than the produced amount of 4-MeOE (FPh: 1.4 +/- 0.1%; LPh: 1.5 +/- 0.1%) (P < 0.05). Both before and after training, incremental exercise did not significantly alter RBC-COMT activity although we observed a trend for RBC-COMT activity increasing proportionally with the exercise intensity. After a brief period of exhaustive training, during rest the formation of 2-MeOE (FPh: +16.7%, LPh: +15.7%) and 4-MeOE (FPh: +28.6%; LPh: +40%) was significantly (P < 0.05) increased. The results of the present study are consistent with earlier findings reporting increased plasma concentrations of O-methylated CE following training. It is concluded that RBC-COMT activity is increased by brief intensive training, but not by acute exercise. We speculate that an increase in COMT-catalyzed O-methylation of CE may indicate that less COMT is available to deactivate norepinephrine.

Catechol-O-methlytransferase inhibition alters pain and anxiety-related volitional behaviors through activation of β-adrenergic receptors in the rat

PubMed Central

Kline, R. H.; Exposto, F. G.; O’Buckley, S. C.; Westlund, K. N.; Nackley, A. G.

2015-01-01

Reduced catechol-O-methyltransferase (COMT) activity resulting from genetic variation or pharmacological depletion results in enhanced pain perception in humans and nociceptive behaviors in animals. Using phasic mechanical and thermal reflex tests (e.g. von Frey, Hargreaves), recent studies show that acute COMT-dependent pain in rats is mediated by β-adrenergic receptors (βARs). In order to more closely mimic the characteristics of human chronic pain conditions associated with prolonged reductions in COMT, the present study sought to determine volitional pain-related and anxiety-like behavioral responses following sustained as well as acute COMT inhibition using an operant 10–45°C thermal place preference task and a light/dark preference test. In addition, we sought to evaluate the effects of sustained COMT inhibition on generalized body pain by measuring tactile sensory thresholds of the abdominal region. Results demonstrated that acute and sustained administration of the COMT inhibitor OR486 increased pain behavior in response to thermal heat. Further, sustained administration of OR486 increased anxiety behavior in response to bright light, as well as abdominal mechanosensation. Finally, all pain-related behaviors were blocked by the non-selective βAR antagonist propranolol. Collectively, these findings provide the first evidence that stimulation of ARs following acute or chronic COMT inhibition drives cognitive-affective behaviors associated with heightened pain that affects multiple body sites. PMID:25659347

Rotator cuff repair augmentation in a rat model that combines a multilayer xenograft tendon scaffold with bone marrow stromal cells

PubMed Central

Omi, Rei; Gingery, Anne; Steinmann, Scott P.; Amadio, Peter C.; An, Kai-Nan; Zhao, Chunfeng

2016-01-01

Hypothesis A composite of multilayer tendon slices (COMTS) seeded with bone marrow stromal cells (BMSCs) may impart mechanical and biologic augmentation effects on supraspinatus tendon repair under tension, thereby improving the healing process after surgery in rats. Methods Adult female Lewis rats (n = 39) underwent transection of the supraspinatus tendon and a 2-mm tendon resection at the distal end, followed by immediate repair to its bony insertion site under tension. Animals received 1 of 3 treatments at the repair site: (1) no augmentation, (2) COMTS augmentation alone, or (3) BMSC-seeded COMTS augmentation. BMSCs were labeled with a fluorescent cell marker. Animals were euthanized 6 weeks after surgery, and the extent of healing of the repaired supraspinatus tendon was evaluated with biomechanical testing and histologic analysis. Results Histologic analysis showed gap formation between the repaired tendon and bone in all specimens, regardless of treatment. Robust fibrous tissue was observed in rats with BMSC-seeded COMTS augmentation; however, fibrous tissue was scarce within the gap in rats with no augmentation or COMTS-only augmentation. Labeled transplanted BMSCs were observed throughout the repair site. Biomechanical analysis showed that the repairs augmented with BMSC-seeded COMTS had significantly greater ultimate load to failure and stiffness compared with other treatments. However, baseline (time 0) data showed that COMTS-only augmentation did not increase mechanical strength of the repair site. Conclusion Although the COMTS scaffold did not increase the initial repair strength, the BMSC-seeded scaffold increased healing strength and stiffness 6 weeks after rotator cuff repair in a rat model. Level of evidence Basic Science Study, Animal Model. PMID:26387915

MAOA and TNF-β gene polymorphisms are associated with photophobia but not osmophobia in patients with migraine.

PubMed

Ishii, Masakazu; Usami, Shino; Hara, Hajime; Imagawa, Atsuko; Masuda, Yutaka; Shimizu, Shuniichi

2014-06-01

Photophobia and osmophobia are typical symptoms associated with migraine, but the contributions of gene polymorphisms to these symptoms are not fully elucidated. We investigated whether the gene polymorphisms are involved in photophobia and osmophobia in patients with migraine. Ninety-one migraine patients and 119 non-headache healthy volunteers were enrolled. The 12 gene polymorphisms were determined by polymerase-chain-reaction (PCR) and PCR restriction-fragment-length polymorphism analysis. Photophobia and osmophobia were observed in 49 (54%) and 31 patients (34%), respectively. Distributions of monoamine oxidase A (MAOA) T941G and tumour necrosis factor-β (TNF-β) G252A polymorphisms were significantly different between patients with photophobia and controls. However, no gene polymorphism differences were observed between patients with osmophobia and controls. The MAOA T941G and TNF-β G252A gene polymorphisms appear to contribute to photophobia but not to osmophobia. We propose that different gene polymorphisms are responsible for photophobia and osmophobia symptoms during migraine.

Introduction to special section on The U.S. IOOS Coastal and Ocean Modeling Testbed

NASA Astrophysics Data System (ADS)

Luettich, Richard A.; Wright, L. Donelson; Signell, Richard; Friedrichs, Carl; Friedrichs, Marjy; Harding, John; Fennel, Katja; Howlett, Eoin; Graves, Sara; Smith, Elizabeth; Crane, Gary; Baltes, Rebecca

2013-12-01

Strong and strategic collaborations among experts from academia, federal operational centers, and industry have been forged to create a U.S. IOOS Coastal and Ocean Modeling Testbed (COMT). The COMT mission is to accelerate the transition of scientific and technical advances from the coastal and ocean modeling research community to improved operational ocean products and services. This is achieved via the evaluation of existing technology or the development of new technology depending on the status of technology within the research community. The initial phase of the COMT has addressed three coastal and ocean prediction challenges of great societal importance: estuarine hypoxia, shelf hypoxia, and coastal inundation. A fourth effort concentrated on providing and refining the cyberinfrastructure and cyber tools to support the modeling work and to advance interoperability and community access to the COMT archive. This paper presents an overview of the initiation of the COMT, the findings of each team and a discussion of the role of the COMT in research to operations and its interface with the coastal and ocean modeling community in general. Detailed technical results are presented in the accompanying series of 16 technical papers in this special issue.

Molecular characterization of a strong candidate region for schizophrenia

DOE Office of Scientific and Technical Information (OSTI.GOV)

Karayiorgou, M.; Housman, D.E.; Morrow, B.

Two lines of evidence point to a region on chromosome 22 as potentially involved in the etiology of schizophrenia: First, our own linkage data and second, observations that a greater than expected number of cases with the VCF (velo-cardio-facial) syndrome, a developmental syndrome due to microdeletions of the same genetic region, develop psychotic illness during adolescence. On the molecular genetic level, we are testing the hypothesis that the partial phenotypic overlap between schizophrenia and VCF may be due to overlapping genetic abnormalities. To that end, we have generated somatic cell hybrids from an initial group of nine VCF patients overmore » the age of 15 who underwent psychiatric evaluation. Three were assigned a DSM-III-R diagnosis of schizophrenia. Several hybrid cell lines were generated from each patient carrying either the deleted chromosome, or the intact chromosome, or both. We have analyzed these hybrids and the extent of their chromosome 22 deletions with 41 markers so far (21 polymorphic microsatellite markers and 20 STSs). One of these markers is COMT (catechol-O-methyltransferase) that could be considered a candidate for schizophrenia. We are searching for potential molecular genetic differences between the subgroup of VCF patients that do develop schizophrenia and the subgroup that do not. Our initial efforts concentrate on the possibility of correlation between the extent of the deletion and the schizophrenic phenotype. Results from our analysis so far will be presented. Our goal is to narrow and define more accurately the region potentially involved in the etiology of schizophrenia and successfully identify any gene(s) that may play a role.« less

Catechol-O-methyltransferase inhibition alters pain and anxiety-related volitional behaviors through activation of β-adrenergic receptors in the rat.

PubMed

Kline, R H; Exposto, F G; O'Buckley, S C; Westlund, K N; Nackley, A G

2015-04-02

Reduced catechol-O-methyltransferase (COMT) activity resulting from genetic variation or pharmacological depletion results in enhanced pain perception in humans and nociceptive behaviors in animals. Using phasic mechanical and thermal reflex tests (e.g. von Frey, Hargreaves), recent studies show that acute COMT-dependent pain in rats is mediated by β-adrenergic receptors (βARs). In order to more closely mimic the characteristics of human chronic pain conditions associated with prolonged reductions in COMT, the present study sought to determine volitional pain-related and anxiety-like behavioral responses following sustained as well as acute COMT inhibition using an operant 10-45°C thermal place preference task and a light/dark preference test. In addition, we sought to evaluate the effects of sustained COMT inhibition on generalized body pain by measuring tactile sensory thresholds of the abdominal region. Results demonstrated that acute and sustained administration of the COMT inhibitor OR486 increased pain behavior in response to thermal heat. Further, sustained administration of OR486 increased anxiety behavior in response to bright light, as well as abdominal mechanosensation. Finally, all pain-related behaviors were blocked by the non-selective βAR antagonist propranolol. Collectively, these findings provide the first evidence that stimulation of βARs following acute or chronic COMT inhibition drives cognitive-affective behaviors associated with heightened pain that affects multiple body sites. Copyright © 2015 IBRO. Published by Elsevier Ltd. All rights reserved.

Environmental Adaptation Contributes to Gene Polymorphism across the Arabidopsis thaliana Genome

PubMed Central

Lee, Cheng-Ruei

2012-01-01

The level of within-species polymorphism differs greatly among genes in a genome. Many genomic studies have investigated the relationship between gene polymorphism and factors such as recombination rate or expression pattern. However, the polymorphism of a gene is affected not only by its physical properties or functional constraints but also by natural selection on organisms in their environments. Specifically, if functionally divergent alleles enable adaptation to different environments, locus-specific polymorphism may be maintained by spatially heterogeneous natural selection. To test this hypothesis and estimate the extent to which environmental selection shapes the pattern of genome-wide polymorphism, we define the "environmental relevance" of a gene as the proportion of genetic variation explained by environmental factors, after controlling for population structure. We found substantial effects of environmental relevance on patterns of polymorphism among genes. In addition, the correlation between environmental relevance and gene polymorphism is positive, consistent with the expectation that balancing selection among heterogeneous environments maintains genetic variation at ecologically important genes. Comparison of the gene ontology annotations shows that genes with high environmental relevance are enriched in unknown function categories. These results suggest an important role for environmental factors in shaping genome-wide patterns of polymorphism and indicate another direction of genomic study. PMID:22798389

Variability in Dopamine Genes Dissociates Model-Based and Model-Free Reinforcement Learning

PubMed Central

Bath, Kevin G.; Daw, Nathaniel D.; Frank, Michael J.

2016-01-01

Considerable evidence suggests that multiple learning systems can drive behavior. Choice can proceed reflexively from previous actions and their associated outcomes, as captured by “model-free” learning algorithms, or flexibly from prospective consideration of outcomes that might occur, as captured by “model-based” learning algorithms. However, differential contributions of dopamine to these systems are poorly understood. Dopamine is widely thought to support model-free learning by modulating plasticity in striatum. Model-based learning may also be affected by these striatal effects, or by other dopaminergic effects elsewhere, notably on prefrontal working memory function. Indeed, prominent demonstrations linking striatal dopamine to putatively model-free learning did not rule out model-based effects, whereas other studies have reported dopaminergic modulation of verifiably model-based learning, but without distinguishing a prefrontal versus striatal locus. To clarify the relationships between dopamine, neural systems, and learning strategies, we combine a genetic association approach in humans with two well-studied reinforcement learning tasks: one isolating model-based from model-free behavior and the other sensitive to key aspects of striatal plasticity. Prefrontal function was indexed by a polymorphism in the COMT gene, differences of which reflect dopamine levels in the prefrontal cortex. This polymorphism has been associated with differences in prefrontal activity and working memory. Striatal function was indexed by a gene coding for DARPP-32, which is densely expressed in the striatum where it is necessary for synaptic plasticity. We found evidence for our hypothesis that variations in prefrontal dopamine relate to model-based learning, whereas variations in striatal dopamine function relate to model-free learning. SIGNIFICANCE STATEMENT Decisions can stem reflexively from their previously associated outcomes or flexibly from deliberative consideration of potential choice outcomes. Research implicates a dopamine-dependent striatal learning mechanism in the former type of choice. Although recent work has indicated that dopamine is also involved in flexible, goal-directed decision-making, it remains unclear whether it also contributes via striatum or via the dopamine-dependent working memory function of prefrontal cortex. We examined genetic indices of dopamine function in these regions and their relation to the two choice strategies. We found that striatal dopamine function related most clearly to the reflexive strategy, as previously shown, and that prefrontal dopamine related most clearly to the flexible strategy. These findings suggest that dissociable brain regions support dissociable choice strategies. PMID:26818509

Biopsychosocial influence on exercise-induced injury: genetic and psychological combinations are predictive of shoulder pain phenotypes.

PubMed

George, Steven Z; Parr, Jeffrey J; Wallace, Margaret R; Wu, Samuel S; Borsa, Paul A; Dai, Yunfeng; Fillingim, Roger B

2014-01-01

Chronic pain is influenced by biological, psychological, social, and cultural factors. The current study investigated potential roles for combinations of genetic and psychological factors in the development and/or maintenance of chronic musculoskeletal pain. An exercise-induced shoulder injury model was used, and a priori selected genetic (ADRB2, COMT, OPRM1, AVPR1 A, GCH1, and KCNS1) and psychological (anxiety, depressive symptoms, pain catastrophizing, fear of pain, and kinesiophobia) factors were included as predictors. Pain phenotypes were shoulder pain intensity (5-day average and peak reported on numerical rating scale), upper extremity disability (5-day average and peak reported on the QuickDASH), and shoulder pain duration (in days). After controlling for age, sex, and race, the genetic and psychological predictors were entered as main effects and interaction terms in separate regression models for the different pain phenotypes. Results from the recruited cohort (N = 190) indicated strong statistical evidence for interactions between the COMT diplotype and 1) pain catastrophizing for 5-day average upper extremity disability and 2) depressive symptoms for pain duration. There was moderate statistical evidence for interactions for other shoulder pain phenotypes between additional genes (ADRB2, AVPR1 A, and KCNS1) and depressive symptoms, pain catastrophizing, or kinesiophobia. These findings confirm the importance of the combined predictive ability of COMT with psychological distress and reveal other novel combinations of genetic and psychological factors that may merit additional investigation in other pain cohorts. Interactions between genetic and psychological factors were investigated as predictors of different exercise-induced shoulder pain phenotypes. The strongest statistical evidence was for interactions between the COMT diplotype and pain catastrophizing (for upper extremity disability) or depressive symptoms (for pain duration). Other novel genetic and psychological combinations were identified that may merit further investigation. Copyright © 2014 American Pain Society. Published by Elsevier Inc. All rights reserved.

Green Tea Modulation of Obesity and Breast Cancer Risk

DTIC Science & Technology

2012-03-01

controlled, double- blind in a subgroup of 300 healthy postmenopausal obese and overweight women with differing COMT genotypes of the parent grant...hormones as well as inflammatory biomarkers of healthy postmenopausal women with differing COMT genotypes. Particularly, this research project will...noted these projections do not meet recruitment of equal numbers of low and high activity COMT genotypes in each experiment group for this training

Back to Essentials: Virtues and Character for Strategic Leaders

DTIC Science & Technology

2012-03-20

religious perspective, this study also includes the set of virtues identified by French philosopher André Comte -Sponville.34 Finally, the model takes... Comte - Sponville Havard PROPOSAL Prudence Wisdom; Prudence Prudence Prudence Prudence Prudence Justice Justice Justice Justice Justice Justice...accessed 20 Jan 2012. 34 Andre Comte -Sponville. A Small Treatrise on the Great Virtues (New York, NY, Metropolitan Books, Henry Holt and Company, LLC

The evaluation of angiotensin-converting enzyme (ACE) gene I/D and IL-4 gene intron 3 VNTR polymorphisms in coronary artery disease.

PubMed

Basol, Nursah; Celik, Atac; Karakus, Nevin; Ozturk, Sibel Demir; Ozsoy, Sibel Demir; Yigit, Serbulent

2014-01-01

Genetic polymorphism is a strong risk factor for coronary artery disease (CAD). In the present study, our aim was to evaluate angiotensin-converting enzyme (ACE) gene I/D polymorphism and interleukin-4 (IL-4) gene Intron 3 variable number of tandem repeat (VNTR) polymorphism in CAD. One hundred and twenty-four CAD patients and one hundred and twenty-three controls were enrolled. Genomic DNA was isolated and genotyped using polymerase chain reaction (PCR) analyses. The risk associated with inheriting the combined genotypes for the two polymorphisms were evaluated and it was found that the individuals who were P2P2-homozygous at IL-4 gene intron 3 VNTR and DD-homozygous at ACE gene I/D have a higher risk of developing CAD. Although, there is no correlation between IL4 VNTR polymorphism and ACE gene polymorphism and CAD, there is a strong association between CAD and co-existence of IL-4 VNTR and ACE gene polymorphisms in the Turkish population. Copyright © 2014 International Institute of Anticancer Research (Dr. John G. Delinassios), All rights reserved.

Folate and Breast Cancer: Role of Intake, Blood Levels, and Metabolic Gene Polymorphisms

DTIC Science & Technology

2006-06-01

polymorphisms . The specific aims are 1) methodological training in the analysis of gene - gene and gene -environment interactions by studying folate...evaluation of folate intake, plasma folate, and metabolic gene polymorphisms in relation to breast cancer risk: Months 1-19. b. Prepare blood samples...isolated for the folate and gene polymorphism assays among the 184 cases and matched controls. The folate assays are on-going at this time and over

[CCR5, CCR2, apoe, p53, ITGB3 and HFE gene polymorphism in Western Siberia long-livers].

PubMed

Ivanoshchuk, D E; Mikhaĭlova, S V; Kulikov, I V; Maksimov, V N; Voevoda, M I; Romashchenko, A G

2012-01-01

In order to estimate the distribution of some polymorphisms for the CCR5, CCR2, apoE, p53, ITGB3, and HFE genes in Russian long-livers from Western Siberia, a sample of 271 individuals (range 90-105 years) was examined. It was demonstrated that carriage of the delta32 polymorphism for the CCR5 gene, V64/polymorphism for the CCR2 gene, e2/e3/e4 for the apoE gene, L33P for the ITGB3 gene, as well as H63D and S65C polymorphisms for the HFE gene does not influence on predisposition to the longevity; carriage of the 282 Y allele for the HFE gene negatively influences on the longevity; carriage of the heterozygous genotype for the R72P polymorphism for the p53 gene correlates with the longevity of elderly people.

Evolution of novel O-methyltransferases from the Vanilla planifolia caffeic acid O-methyltransferase.

PubMed

Li, Huaijun Michael; Rotter, David; Hartman, Thomas G; Pak, Fulya E; Havkin-Frenkel, Daphna; Belanger, Faith C

2006-06-01

The biosynthesis of many plant secondary compounds involves the methylation of one or more hydroxyl groups, catalyzed by O-methyltransferases (OMTs). Here, we report the characterization of two OMTs, Van OMT-2 and Van OMT-3, from the orchid Vanilla planifolia Andrews. These enzymes catalyze the methylation of a single outer hydroxyl group in substrates possessing a 1,2,3-trihydroxybenzene moiety, such as methyl gallate and myricetin. This is a substrate requirement not previously reported for any OMTs. Based on sequence analysis these enzymes are most similar to caffeic acid O-methyltransferases (COMTs), but they have negligible activity with typical COMT substrates. Seven of 12 conserved substrate-binding residues in COMTs are altered in Van OMT-2 and Van OMT-3. Phylogenetic analysis of the sequences suggests that Van OMT-2 and Van OMT-3 evolved from the V. planifolia COMT. These V. planifolia OMTs are new instances of COMT-like enzymes with novel substrate preferences.

Does adult ADHD interact with COMT val (158) met genotype to influence working memory performance?

PubMed

Biehl, Stefanie C; Gschwendtner, Kathrin M; Guhn, Anne; Müller, Laura D; Reichert, Susanne; Heupel, Julia; Reif, Andreas; Deckert, Jürgen; Herrmann, Martin J; Jacob, Christian P

2015-03-01

Both attention-deficit/hyperactivity disorder (ADHD) and catechol-O-methyltransferase (COMT) genotype have been linked to altered dopaminergic transmission and possible impairment in frontal lobe functioning. This study offers an investigation of a possible interaction between ADHD diagnosis and COMT genotype on measures of working memory and executive function. Thirty-five adults with ADHD, who were recruited from the ADHD outpatient clinic at the Department of Psychiatry, Psychosomatics and Psychotherapy, University of Würzburg, and thirty-five matched healthy controls completed the Digit Span test and the Stroop Color Word Test. While there were no main effects of ADHD or COMT, the two factors interacted on both Digit Span subtests with the two groups' met/met carriers showing significantly different performance on the Digit Span Forward subtest and the val/val carriers showing significantly different performance on the Digit Span Backward subtest. Findings provide preliminary support for a differential impact of COMT genotype on working memory measures in adult patients with ADHD compared to healthy controls.

Green Tea Modulation of Obesity and Breast Cancer Risk

DTIC Science & Technology

2013-04-01

samples in serum and plasma will start in early May 2013, and it is anticipated that the last run of analyses to be finished by the middle of August ...postmenopausal women, and whether any observed changes vary by the catechol-O-methyltransferase ( COMT ) genotype. Abovementioned measurements will be...activity COMT group, there were previously some concerns with recruitment of enough high activity COMT genotype participants. However, given current

Biopsychosocial influence on exercise-induced injury: genetic and psychological combinations are predictive of shoulder pain phenotypes

PubMed Central

George, Steven Z.; Parr, Jeffrey J.; Wallace, Margaret R.; Wu, Samuel S.; Borsa, Paul A.; Dai, Yunfeng; Fillingim, Roger B.

2014-01-01

Chronic pain is influenced by biological, psychological, social, and cultural factors. The current study investigated potential roles for combinations of genetic and psychological factors in the development and/or maintenance of chronic musculoskeletal pain. An exercise-induced shoulder injury model was used and a priori selected genetic (ADRB2, COMT, OPRM1, AVPR1A, GCH1, and KCNS1) and psychological (anxiety, depressive symptoms, pain catastrophizing, fear of pain, and kinesiophobia) factors were included as predictors. Pain phenotypes were shoulder pain intensity (5-day average and peak reported on numerical rating scale), upper-extremity disability (5-day average and peak reported on the QuickDASH), and shoulder pain duration (in days). After controlling for age, sex, and race the genetic and psychological predictors were entered as main effects and interaction terms in separate regression models for the different pain phenotypes. Results from the recruited cohort (n = 190) indicated strong statistical evidence for interactions between the COMT diplotype and 1) pain catastrophizing for 5-day average upper-extremity disability and 2) depressive symptoms for pain duration. There was moderate statistical evidence for interactions for other shoulder pain phenotypes between additional genes (ADRB2, AVPR1A, and KCNS1) and depressive symptoms, pain catastrophizing, or kinesiophobia. These findings confirm the importance of the combined predictive ability of COMT with psychological distress, and reveal other novel combinations of genetic and psychological factors that may merit additional investigation in other pain cohorts. PMID:24373571

Tea intake, COMT genotype, and breast cancer in Asian-American women.

PubMed

Wu, Anna H; Tseng, Chiu-Chen; Van Den Berg, David; Yu, Mimi C

2003-11-01

There is substantial in vitro and in vivo evidence implicating tea polyphenols as chemopreventive agents against various cancers. In a case-control study conducted among Asian-American women in Los Angeles County, we reported a significant inverse relationship between intake of green tea and risk of breast cancer (A. H. Wu et al., Int. J. Cancer, 106: 574-579, 2003). Because catechol-containing tea polyphenols are very rapidly O-methylated by human catechol-O-methyltransferase (COMT), we are interested in determining whether the association between tea intake and breast cancer differed in women according to COMT genotype. We examined the interrelationships between tea intake, COMT genotype, and breast cancer risk in 589 incident cases and 563 population-based controls from a population-based case-control study of breast cancer in Chinese-, Japanese-, and Filipino-American women in Los Angeles County. Risk of breast cancer was influenced significantly by intake of tea, particularly green tea intake. However, the inverse association between tea intake and breast cancer risk was observed only among individuals who possessed at least one low-activity COMT allele. Among women who carried at least one low activity COMT allele, tea drinkers showed a significantly reduced risk of breast cancer (adjusted odds ratio, 0.48; 95% confidence interval, 0.29-0.77) compared with nontea drinkers after adjustment for relevant demographic, menstrual, reproductive, and dietary factors. This risk reduction was observed in relation to both green tea and black tea intake. In contrast, risk of breast cancer did not differ between tea drinkers and nontea drinkers among those who were homozygous for the high activity COMT allele (adjusted odds ratio, 1.02; 95% confidence interval, 0.66-1.60). In conclusion, tea catechins appeared to reduce breast cancer risk in this study of Asian-American women. Reduction in risk was strongest among persons who had the low activity COMT alleles, suggesting these individuals were less efficient in eliminating tea catechins and may derive the most benefit from these compounds.

Identification of possible genetic polymorphisms involved in cancer cachexia: a systematic review.

PubMed

Tan, Benjamin H L; Ross, James A; Kaasa, Stein; Skorpen, Frank; Fearon, Kenneth C H

2011-04-01

Cancer cachexia is a polygenic and complex syndrome. Genetic variations in regulation of the inflammatory response, muscle and fat metabolic pathways, and pathways in appetite regulation are likely to contribute to the susceptibility or resistance to developing cancer cachexia. A systematic search of Medline and EmBase databases, covering 1986-2008 was performed for potential candidate genes/genetic polymorphisms relating to cancer cachexia. Related genes were then identified using pathway functional analysis software. All candidate genes were reviewed for functional polymorphisms or clinically significant polymorphisms associated with cachexia using the OMIM and GeneRIF databases. Genes with variants which had functional or clinical associations with cachexia and replicated in at least one study were entered into pathway analysis software to reveal possible network associations between genes. A total of 184 polymorphisms with functional or clinical relevance to cancer cachexia were identified in 92 candidate genes. Of these, 42 polymorphisms (in 33 genes) were replicated in more than one study with 13 polymorphisms found to influence two or more hallmarks of cachexia (i.e. inflammation, loss of fat mass and/or lean mass and reduced survival). Thirty-three genes were found to be significantly interconnected in two major networks with four genes (ADIPOQ, IL6, NFKB1 and TLR4) interlinking both networks. Selection of candidate genes and polymorphisms is a key element of multigene study design. The present study provides an initial framework to select genes/polymorphisms for further study in cancer cachexia, and to develop their potential as susceptibility biomarkers of developing cachexia.

Factors Affecting the Performance of Hispanic and Non-Hispanic Marine Corps Enlistees

DTIC Science & Technology

2015-03-01

more than one summary comt -mruiial. Not more than two non-judicial punishments. Punitive reduction in grade. No comt -mrutial. Not more than one...obedience, after-effects of intemperance, comt esy and consideration, and observance of regulations. No offenses. Positive favorable impressions of...lecture, 6 August 31 2014). This is also one of the weaknesses of the study. The authors discover that many MOS have a significant effect on

Polymorphisms at the Ligand Binding Site of the Vitamin D Receptor Gene and Osteomalacia

PubMed Central

Ak, Duygu Gezen; Kahraman, Hakkí; Dursun, Erdinç; Duman, Belgin Süsleyici; Erensoy, Nevin; Alagöl, Faruk; Tanakol, Refik; Yılmazer, Selma

2005-01-01

Vitamin D receptor (VDR) gene polymorphisms have been suggested as possible determinants of bone mineral density (BMD) and calcium metabolism. In this study, our aim was to determine whether there is an association between VDR gene polymorphism and osteomalacia or not. We determined ApaI and TaqI polymorphisms in the vitamin D receptor gene in 24 patients with osteomalacia and 25 age-matched healthy controls. Serum calcium, phosphorus, ALP, PTH, 25OHD levels were also examined. We used PCR and RFLP methods to test for an association between osteomalacia and polymorphisms within, intron 8 and exon 9 of the VDR gene. When the control and patients were compared for their ApaI and TaqI genotypes there was no relationship between VDR gene allelic polymorphisms and osteomalacia. Whereas a nearly significant difference for A allele was found in the allellic distribution of the patients (p = 0.08). Also no association between biochemical data and VDR gene polymorphisms was observed. PMID:16403954

[Polymorphic loci and polymorphism analysis of short tandem repeats within XNP gene].

PubMed

Liu, Qi-Ji; Gong, Yao-Qin; Guo, Chen-Hong; Chen, Bing-Xi; Li, Jiang-Xia; Guo, Yi-Shou

2002-01-01

To select polymorphic short tandem repeat markers within X-linked nuclear protein (XNP) gene, genomic clones which contain XNP gene were recognized by homologous analysis with XNP cDNA. By comparing the cDNA with genomic DNA, non-exonic sequences were identified, and short tandem repeats were selected from non-exonic sequences by using BCM search Launcher. Polymorphisms of the short tandem repeats in Chinese population were evaluated by PCR amplification and PAGE. Five short tandem repeats were identified from XNP gene, two of which were polymorphic. Four and 11 alleles were observed in Chinese population for XNPSTR1 and XNPSTR4, respectively. Heterozygosities were 47% for XNPSTR1 and 70% for XNPSTR4. XNPSTR1 and XNPSTR4 localized within 3' end and intron 10, respectively. Two polymorphic short tandem repeats have been identified within XNP gene and will be useful for linkage analysis and gene diagnosis of XNP gene.

Artificial neural network-based exploration of gene-nutrient interactions in folate and xenobiotic metabolic pathways that modulate susceptibility to breast cancer.

PubMed

Naushad, Shaik Mohammad; Ramaiah, M Janaki; Pavithrakumari, Manickam; Jayapriya, Jaganathan; Hussain, Tajamul; Alrokayan, Salman A; Gottumukkala, Suryanarayana Raju; Digumarti, Raghunadharao; Kutala, Vijay Kumar

2016-04-15

In the current study, an artificial neural network (ANN)-based breast cancer prediction model was developed from the data of folate and xenobiotic pathway genetic polymorphisms along with the nutritional and demographic variables to investigate how micronutrients modulate susceptibility to breast cancer. The developed ANN model explained 94.2% variability in breast cancer prediction. Fixed effect models of folate (400 μg/day) and B12 (6 μg/day) showed 33.3% and 11.3% risk reduction, respectively. Multifactor dimensionality reduction analysis showed the following interactions in responders to folate: RFC1 G80A × MTHFR C677T (primary), COMT H108L × CYP1A1 m2 (secondary), MTR A2756G (tertiary). The interactions among responders to B12 were RFC1G80A × cSHMT C1420T and CYP1A1 m2 × CYP1A1 m4. ANN simulations revealed that increased folate might restore ER and PR expression and reduce the promoter CpG island methylation of extra cellular superoxide dismutase and BRCA1. Dietary intake of folate appears to confer protection against breast cancer through its modulating effects on ER and PR expression and methylation of EC-SOD and BRCA1. Copyright © 2016 Elsevier B.V. All rights reserved.

Age is no barrier: predictors of academic success in older learners

NASA Astrophysics Data System (ADS)

Imlach, Abbie-Rose; Ward, David D.; Stuart, Kimberley E.; Summers, Mathew J.; Valenzuela, Michael J.; King, Anna E.; Saunders, Nichole L.; Summers, Jeffrey; Srikanth, Velandai K.; Robinson, Andrew; Vickers, James C.

2017-11-01

Although predictors of academic success have been identified in young adults, such predictors are unlikely to translate directly to an older student population, where such information is scarce. The current study aimed to examine cognitive, psychosocial, lifetime, and genetic predictors of university-level academic performance in older adults (50-79 years old). Participants were mostly female (71%) and had a greater than high school education level (M = 14.06 years, SD = 2.76), on average. Two multiple linear regression analyses were conducted. The first examined all potential predictors of grade point average (GPA) in the subset of participants who had volunteered samples for genetic analysis (N = 181). Significant predictors of GPA were then re-examined in a second multiple linear regression using the full sample (N = 329). Our data show that the cognitive domains of episodic memory and language processing, in conjunction with midlife engagement in cognitively stimulating activities, have a role in predicting academic performance as measured by GPA in the first year of study. In contrast, it was determined that age, IQ, gender, working memory, psychosocial factors, and common brain gene polymorphisms linked to brain function, plasticity and degeneration (APOE, BDNF, COMT, KIBRA, SERT) did not influence academic performance. These findings demonstrate that ageing does not impede academic achievement, and that discrete cognitive skills as well as lifetime engagement in cognitively stimulating activities can promote academic success in older adults.

Genetic basis of interindividual susceptibility to cancer cachexia: selection of potential candidate gene polymorphisms for association studies.

PubMed

Johns, N; Tan, B H; MacMillan, M; Solheim, T S; Ross, J A; Baracos, V E; Damaraju, S; Fearon, K C H

2014-12-01

Cancer cachexia is a complex and multifactorial disease. Evolving definitions highlight the fact that a diverse range of biological processes contribute to cancer cachexia. Part of the variation in who will and who will not develop cancer cachexia may be genetically determined. As new definitions, classifications and biological targets continue to evolve, there is a need for reappraisal of the literature for future candidate association studies. This review summarizes genes identified or implicated as well as putative candidate genes contributing to cachexia, identified through diverse technology platforms and model systems to further guide association studies. A systematic search covering 1986-2012 was performed for potential candidate genes / genetic polymorphisms relating to cancer cachexia. All candidate genes were reviewed for functional polymorphisms or clinically significant polymorphisms associated with cachexia using the OMIM and GeneRIF databases. Pathway analysis software was used to reveal possible network associations between genes. Functionality of SNPs/genes was explored based on published literature, algorithms for detecting putative deleterious SNPs and interrogating the database for expression of quantitative trait loci (eQTLs). A total of 154 genes associated with cancer cachexia were identified and explored for functional polymorphisms. Of these 154 genes, 119 had a combined total of 281 polymorphisms with functional and/or clinical significance in terms of cachexia associated with them. Of these, 80 polymorphisms (in 51 genes) were replicated in more than one study with 24 polymorphisms found to influence two or more hallmarks of cachexia (i.e., inflammation, loss of fat mass and/or lean mass and reduced survival). Selection of candidate genes and polymorphisms is a key element of multigene study design. The present study provides a contemporary basis to select genes and/or polymorphisms for further association studies in cancer cachexia, and to develop their potential as susceptibility biomarkers of cachexia.

Gene Presence-Absence Polymorphism in Castrating Anther-Smut Fungi: Recent Gene Gains and Phylogeographic Structure.

PubMed

Hartmann, Fanny E; Rodríguez de la Vega, Ricardo C; Brandenburg, Jean-Tristan; Carpentier, Fantin; Giraud, Tatiana

2018-04-01

Gene presence-absence polymorphisms segregating within species are a significant source of genetic variation but have been little investigated to date in natural populations. In plant pathogens, the gain or loss of genes encoding proteins interacting directly with the host, such as secreted proteins, probably plays an important role in coevolution and local adaptation. We investigated gene presence-absence polymorphism in populations of two closely related species of castrating anther-smut fungi, Microbotryum lychnidis-dioicae (MvSl) and M. silenes-dioicae (MvSd), from across Europe, on the basis of Illumina genome sequencing data and high-quality genome references. We observed presence-absence polymorphism for 186 autosomal genes (2% of all genes) in MvSl, and only 51 autosomal genes in MvSd. Distinct genes displayed presence-absence polymorphism in the two species. Genes displaying presence-absence polymorphism were frequently located in subtelomeric and centromeric regions and close to repetitive elements, and comparison with outgroups indicated that most were present in a single species, being recently acquired through duplications in multiple-gene families. Gene presence-absence polymorphism in MvSl showed a phylogeographic structure corresponding to clusters detected based on SNPs. In addition, gene absence alleles were rare within species and skewed toward low-frequency variants. These findings are consistent with a deleterious or neutral effect for most gene presence-absence polymorphism. Some of the observed gene loss and gain events may however be adaptive, as suggested by the putative functions of the corresponding encoded proteins (e.g., secreted proteins) or their localization within previously identified selective sweeps. The adaptive roles in plant and anther-smut fungi interactions of candidate genes however need to be experimentally tested in future studies.

Gene Presence–Absence Polymorphism in Castrating Anther-Smut Fungi: Recent Gene Gains and Phylogeographic Structure

PubMed Central

Rodríguez de la Vega, Ricardo C; Brandenburg, Jean-Tristan; Carpentier, Fantin; Giraud, Tatiana

2018-01-01

Abstract Gene presence–absence polymorphisms segregating within species are a significant source of genetic variation but have been little investigated to date in natural populations. In plant pathogens, the gain or loss of genes encoding proteins interacting directly with the host, such as secreted proteins, probably plays an important role in coevolution and local adaptation. We investigated gene presence–absence polymorphism in populations of two closely related species of castrating anther-smut fungi, Microbotryum lychnidis-dioicae (MvSl) and M. silenes-dioicae (MvSd), from across Europe, on the basis of Illumina genome sequencing data and high-quality genome references. We observed presence–absence polymorphism for 186 autosomal genes (2% of all genes) in MvSl, and only 51 autosomal genes in MvSd. Distinct genes displayed presence–absence polymorphism in the two species. Genes displaying presence–absence polymorphism were frequently located in subtelomeric and centromeric regions and close to repetitive elements, and comparison with outgroups indicated that most were present in a single species, being recently acquired through duplications in multiple-gene families. Gene presence–absence polymorphism in MvSl showed a phylogeographic structure corresponding to clusters detected based on SNPs. In addition, gene absence alleles were rare within species and skewed toward low-frequency variants. These findings are consistent with a deleterious or neutral effect for most gene presence–absence polymorphism. Some of the observed gene loss and gain events may however be adaptive, as suggested by the putative functions of the corresponding encoded proteins (e.g., secreted proteins) or their localization within previously identified selective sweeps. The adaptive roles in plant and anther-smut fungi interactions of candidate genes however need to be experimentally tested in future studies. PMID:29722826

Brain Immune Interactions as the Basis of Gulf War Illness: Gulf War Illness Consortium (GWIC)

DTIC Science & Technology

2015-10-01

August to train all clinical staff and to ensure proper quality control measures are in place for the clinical studies. This has been followed up by...clinical and preclinical studies Training for researchers and clinical staff was completed at in-person meeting in Boston in August 2014 and continued to...Catechol-O- methyl transferase ( COMT ). COMT is associated with synaptic catecholamine neurotransmitters. COMT helps regulate cortical dopamine in the

The Idea of a Fleet in Being in Historical Perspective

DTIC Science & Technology

2014-01-01

Parliament explaining the ratio- nale for his actions in the battle of beachy Head (Cap béveziers). In that action, the comte de tourville, with...parture of a french squadron under the comte d’estaing to North america and then to the West Indies. the government in london now changed its...they fought were indecisive. Meanwhile, in european waters, in the first major naval battle of the war, a french fleet under the comte d’orvilliers

The Evaluation of IL6 and ESR1 Gene Polymorphisms in Primary Dysmenorrhea.

PubMed

Ozsoy, Asker Zeki; Karakus, Nevin; Yigit, Serbulent; Cakmak, Bulent; Nacar, Mehmet Can; Yılmaz Dogru, Hatice

2016-01-01

Primary dysmenorrhea is the most common gynecological complaint with painful menstrual cramps in pelvis without any pathology. It affects about half of menstruating women, and it causes significant disruption in quality of life. We investigated the association between IL6 gene promoter and ESR1 gene XbaI and PvuII polymorphisms and primary dysmenorrhea. In this case-control study, 152 unrelated young women with primary dysmenorrhea and 150 unrelated healthy age-matched controls participated. Genomic DNA was isolated and IL6 and ESR1 gene polymorphisms were genotyped using PCR-based RFLP assay. The distribution of genotype and allele frequencies of IL6 gene promoter and ESR1 gene XbaI polymorphisms were not statistically different between patients and controls (p > 0.05). However, the genotype and allele frequencies of ESR1 gene PvuII polymorphism showed statistically significant differences between primary dysmenorrhea patients and controls (p = 0.009 and p = 0.021, respectively). Statistically significant associations were also observed between age and married status of primary dysmenorrhea patients and ESR1 gene PvuII polymorphism (p = 0.044 and p = 0.023, respectively). In combined genotype analyses, AG at ESR1 XbaI and TC at ESR1 PvuII loci encoded a p-value of 0.027. Thus, individuals who are heterozygote at both loci have a lower risk of developing primary dysmenorrhea. Our study suggests no strong association between IL6 gene promoter and ESR1 gene XbaI polymorphisms and primary dysmenorrhea in Turkish women. However, ESR1 gene PvuII polymorphism showed statistically significant differences between primary dysmenorrhea patients and controls. The potential association between ESR1 gene PvuII polymorphism and age and married status of dysmenorrhea patients deserves further consideration.

Pharmacophore-based virtual screening of catechol-o-methyltransferase (COMT) inhibitors to combat Alzheimer's disease.

PubMed

Patel, Chirag N; Georrge, John J; Modi, Krunal M; Narechania, Moksha B; Patel, Daxesh P; Gonzalez, Frank J; Pandya, Himanshu A

2017-12-27

Alzheimer's disease (AD) is one of the most significant neurodegenerative disorders and its symptoms mostly appear in aged people. Catechol-o-methyltransferase (COMT) is one of the known target enzymes responsible for AD. With the use of 23 known inhibitors of COMT, a query has been generated and validated by screening against the database of 1500 decoys to obtain the GH score and enrichment value. The crucial features of the known inhibitors were evaluated by the online ZINC Pharmer to identify new leads from a ZINC database. Five hundred hits were retrieved from ZINC Pharmer and by ADMET (absorption, distribution, metabolism, excretion, and toxicity) filtering by using FAF-Drug-3 and 36 molecules were considered for molecular docking. From the COMT inhibitors, opicapone, fenoldopam, and quercetin were selected, while ZINC63625100_413 ZINC39411941_412, ZINC63234426_254, ZINC63637968_451, and ZINC64019452_303 were chosen for the molecular dynamics simulation analysis having high binding affinity and structural recognition. This study identified the potential COMT inhibitors through pharmacophore-based inhibitor screening leading to a more complete understanding of molecular-level interactions.

Selection with Gene-Cytoplasm Interactions. I. Maintenance of Cytoplasm Polymorphisms

PubMed Central

Gregorius, H. R.; Ross, M. D.

1984-01-01

General conditions for the protectedness of gene-cytoplasm polymorphisms are considered for a biallelic model with two cytoplasm types and under the assumption that nuclear polymorphisms cannot be maintained in the presence of only one cytoplasm type. Analytical results involving male fertilities, female fertilities, viabilities and selfing rates are obtained, and numerical results show spiral and cyclic behavior of population trajectories. It is shown that a maternally inherited cytoplasmic polymorphism cannot be maintained in the absence of a nuclear polymorphism, and that a gene-cytoplasm polymorphism can only be maintained if the population shows sexual asymmetry, i.e. , if the ratio of male to female fertility varies among genotypes. Thus, the classical viability selection model does not allow gene-cytoplasm polymorphisms. PMID:17246213

The Joint Effects of Body Mass Index and MAOA Gene Polymorphism on Depressive Symptoms.

PubMed

Liu, Yangyang

2015-07-01

The objective of the present study was to examine the joint effects of the body mass index and the MAOA gene polymorphism on depressive symptoms. In two independent Chinese samples, we measured adolescents' depressive symptoms and body mass index and collected their DNA. The results indicated that the main effects of the MAOA gene polymorphism on depressive symptoms were significant. However, the main effects of body mass index and the interaction of the MAOA gene polymorphism and body mass index on depressive symptoms were not significant. By using Chinese adolescents, this study confirmed that the MAOA gene polymorphism directly influenced adolescents' depressive symptoms.

Association of interleukins genes polymorphisms with multi-drug resistant tuberculosis in Ukrainian population.

PubMed

Butov, Dmytro O; Kuzhko, Mykhaylo M; Makeeva, Natalia I; Butova, Tetyana S; Stepanenko, Hanna L; Dudnyk, Andrii B

2016-01-01

Multi-drug resistant tuberculosis (MDR TB) is a significant health problem in some parts of the world. Three major cytokines involved in TB immunopathogenesis include IL-2, IL-4 and IL-10. The susceptibility to MDR TB may be genetically determined. The aim of the study was to assess the association of IL-2, IL-4, IL-10 gene polymorphisms with multi-drug resistant tuberculosis (MDR TB) in Ukrainian population. We observed 140 patients suffering from infiltrative pulmonary tuberculosis (PT) and 30 apparently healthy subjects. The patients were assigned to two groups whether they suffer or do not suffer from pulmonary MDR TB. Interleukin gene (IL) polymorphisms, particularly T330G polymorphism in the IL-2 gene, C589T polymorphism in the IL-4 gene and G1082A polymorphism in the IL-10 gene were studied through polymerase chain reaction. Circulating levels of IL-2, IL-4 and IL-10 in venous blood were estimated using ELISA. Prior to treatment, patients with PT showed significant increase of IL-2 levels and decrease of IL-4 and IL-10 levels compared to apparently healthy subjects. Circulating IL-4 and IL-10 levels were significantly decreased whilst serum IL-2 level was significantly increased in patients with MDR TB compared to non-MDR TB. Low IL-4 and IL-10 secretion and considerable IL-2 alterations were shown to be significantly associated with mutations of homozygous and heterozygous genotypes affecting C589T polymorphism in the IL-4 gene, G1082A polymorphism in the IL-10 gene and T330G polymorphism in the IL-2 gene in patients with PT. Heterozygous genotype and mutations homozygous genotypes gene in polymorphisms determining specified cytokines' production is a PT risk factor and may lead to disease progression into chronic phase. Heterozygous genotype of aforementioned cytokine genetic polymorphisms was significantly the most frequent in patients with MDR TB.

Estimation of the relationship between the polymorphisms of selected genes: ACE, AGTR1, TGFβ1 and GNB3 with the occurrence of primary vesicoureteral reflux.

PubMed

Życzkowski, Marcin; Żywiec, Joanna; Nowakowski, Krzysztof; Paradysz, Andrzej; Grzeszczak, Władyslaw; Gumprecht, Janusz

2017-03-01

Etiopathogenesis of VUR is composite and not fully understood. Many data indicate the importance of genetic predisposition. The aim of this study was to establish the relationship of selected polymorphisms: 14094 polymorphism of the ACE, polymorphism rs1800469 of TGFβ-1, rs5443 gene polymorphism of the GNB3 and receptor gene polymorphism rs5186 type 1 AGTR1 with the occurrence of the primary vesicoureteral reflux. The study included 190 children: 90 with the primary VUR confirmed with the voiding cystourethrogram and excluded secondary VUR and a control group of 100 children without a history of the diseases of the genitourinary tract. The study was planned in the scheme: "tested case versus control." Genomic DNA was isolated from the leukocytes of peripheral blood samples. The results were statistically analyzed in the Statistica 10 using χ 2 test and analysis of the variance Anova. Any of the four studied polymorphisms showed no difference in the distribution of genotypes between patients with primary vesicoureteral reflux and the control group. In patients with VUR and TT genotype polymorphism rs5443 GNB3 gene, the glomerular filtration rate was significantly higher than in patients with genotype CC or CT. (1) No relationship was found between the studied polymorphisms (14094 ACE gene, rs1800469 gene TGFβ1, GNB3 gene rs5443, rs5186 AGTR1 gene) and the occurrence of primary vesicoureteral reflux. (2) TT genotype polymorphism rs5443 GNB3 gene may be a protective factor for the improved renal function in patients with primary vesicoureteral reflux in patients with genotype CC or CT.

Association of Calpain (CAPN) 10 (UCSNP-43, rs3792267) gene polymorphism with elevated serum androgens in young women with the most severe phenotype of polycystic ovary syndrome (PCOS).

PubMed

Anastasia, Karela; Koika, Vasiliki; Roupas, Nikolaos D; Armeni, Anastasia; Marioli, Dimitra; Panidis, Dimitrios; George, Adonakis; Georgopoulos, Neoklis A

2015-01-01

To highlight a possible association of Calpain (CAPN 10) gene UCSNP-43 polymorphism with hormonal and metabolic traits of young women with different phenotypes of polycystic ovary syndrome (PCOS). PCOS women were genotyped for the CAPN 10 gene UCSNP-43 polymorphism. A comparison of clinical and biochemical features of women with PCOS stratified on the basis of the CAPN 10 gene UCSNP-43 variants was assessed. Anthropometric, hormonal and biochemical measurements were carried out in 668 PCOS women and 200 healthy controls. Subjects were also genotyped for the CAPN 10 gene UCSNP-43 polymorphism. The genotype frequency distributions between groups and controls were compared using the chi-square test. The association of the polymorphism with the clinical and biochemical features of the study cohort was estimated as well. No association of the frequency of CAPN 10 gene UCSNP-43 polymorphism with PCOS was detected. No association of the polymorphism with the anthropometric, biochemical and hormonal features was detected both in PCOS and control women. The polymorphism was associated with serum Δ4 androstenedione (p = 0.018), as well as with 17-OH progesterone (17-hydroxyprogesterone) among women with PCOS phenotype A (p = 0.012). CAPN 10 gene polymorphism UCSNP-43 is deprived of a metabolic contribution to cardiovascular disease (CVD). However, due to its association with androgen excess in phenotype A, CAPN 10 gene polymorphism UCSNP-43 could be used as a genetic marker for CVD in young PCOS women.

Association of TNFα-308, IFNγ+874, and IL10-1082 gene polymorphisms and the risk of non-small cell lung cancer in the population of the South Indian state of Telangana.

PubMed

Peddireddy, Vidyullatha; Badabagni, Siva Prasad; Sulthana, Shehnaz; Kolla, Venkata Karunakar; Gundimeda, Sandhya Devi; Mundluru, Hemaprasad

2016-10-01

Cytokine-mediated inflammation is important in the pathogenesis of non-small cell lung cancer (NSCLC). Genetic polymorphisms in cytokine genes and their association with lung cancer in the Indian population have not been reported. For the first time, we analyzed genetic polymorphisms of TNFα -308 , IFNγ +874 , and IL10 -1082 genes in 246 NSCLC patients and 250 healthy controls in the South Indian population from Telangana using ARMS PCR. IFNγ +874 A/T and IL10 -1082 G/G gene polymorphisms were found to be significantly associated with NSCLC with 1.56- and 1.68-fold disease risk, respectively. There was no association between the risk of NSCLC and TNFα -308 polymorphism. Gene polymorphisms stratified according to smoking revealed that IFNγ +874 A/T polymorphisms in smokers increased the disease risk by 2.91 fold. IL10 -1082 G/G polymorphisms showed 2-fold increased risk among patients who were smokers when compared to the controls. However, there was no association between TNFα -308 , IFNγ +874 , and IL10 -1082 gene polymorphism and the stage of the NSCLC patients. The overall risk associated with the combination of these polymorphisms indicated that the TNFα -308 G/A + IFNγ +874 A/T + IL10 -1082 G/G genotype increased the risk by 1.5 fold. The results of our study indicate an association between cytokine gene polymorphisms and the risk of NSCLC in an Indian population.

Are "functionally related polymorphisms" of renin-angiotensin-aldosterone system gene polymorphisms associated with hypertension?

PubMed

Hahntow, Ines N; Mairuhu, Gideon; van Valkengoed, Irene Gm; Koopmans, Richard P; Michel, Martin C

2010-06-02

Genotype-phenotype association studies are typically based upon polymorphisms or haplotypes comprised of multiple polymorphisms within a single gene. It has been proposed that combinations of polymorphisms in distinct genes, which functionally impact the same phenotype, may have stronger phenotype associations than those within a single gene. We have tested this hypothesis using genes encoding components of the renin-angiotensin-aldosterone system and the high blood pressure phenotype. Our analysis is based on 1379 participants of the cross-sectional SUNSET study randomly selected from the population register of Amsterdam. Each subject was genotyped for the angiotensinogen M235T, the angiotensin-converting enzyme insertion/deletion and the angiotensin II type 1 receptor A1166C polymorphism. The phenotype high blood pressure was defined either as a categorical variable comparing hypertension versus normotension as in most previous studies or as a continuous variable using systolic, diastolic and mean blood pressure in a multiple regression analysis with gender, ethnicity, age, body-mass-index and antihypertensive medication as covariates. Genotype-phenotype relationships were explored for each polymorphism in isolation and for double and triple polymorphism combinations. At the single polymorphism level, only the A allele of the angiotensin II type 1 receptor was associated with a high blood pressure phenotype. Using combinations of polymorphisms of two or all three genes did not yield stronger/more consistent associations. We conclude that combinations of physiologically related polymorphisms of multiple genes, at least with regard to the renin-angiotensin-aldosterone system and the hypertensive phenotype, do not necessarily offer additional benefit in analyzing genotype/phenotype associations.

Microarray study of single nucleotide polymorphisms and expression of ATP-binding cassette genes in breast tumors

NASA Astrophysics Data System (ADS)

Tsyganov, M. M.; Ibragimova, M. K.; Karabut, I. V.; Freydin, M. B.; Choinzonov, E. L.; Litvyakov, N. V.

2015-11-01

Our previous research establishes that changes of expression of the ATP-binding cassette genes family is connected with the neoadjuvant chemotherapy effect. However, the mechanism of regulation of resistance gene expression remains unclear. As many researchers believe, single nucleotide polymorphisms can be involved in this process. Thereupon, microarray analysis is used to study polymorphisms in ATP-binding cassette genes. It is thus found that MDR gene expression is connected with 5 polymorphisms, i.e. rs241432, rs241429, rs241430, rs3784867, rs59409230, which participate in the regulation of expression of own genes.

Dynamic interaction between fetal adversity and a genetic score reflecting dopamine function on developmental outcomes at 36 months.

PubMed

Bischoff, Adrianne R; Pokhvisneva, Irina; Léger, Étienne; Gaudreau, Hélène; Steiner, Meir; Kennedy, James L; O'Donnell, Kieran J; Diorio, Josie; Meaney, Michael J; Silveira, Patrícia P

2017-01-01

Fetal adversity, evidenced by poor fetal growth for instance, is associated with increased risk for several diseases later in life. Classical cut-offs to characterize small (SGA) and large for gestational age (LGA) newborns are used to define long term vulnerability. We aimed at exploring the possible dynamism of different birth weight cut-offs in defining vulnerability in developmental outcomes (through the Bayley Scales of Infant and Toddler Development), using the example of a gene vs. fetal adversity interaction considering gene choices based on functional relevance to the studied outcome. 36-month-old children from an established prospective birth cohort (Maternal Adversity, Vulnerability, and Neurodevelopment) were classified according to birth weight ratio (BWR) (SGA ≤0.85, LGA >1.15, exploring a wide range of other cut-offs) and genotyped for polymorphisms associated with dopamine signaling (TaqIA-A1 allele, DRD2-141C Ins/Ins, DRD4 7-repeat, DAT1-10- repeat, Met/Met-COMT), composing a score based on the described function, in which hypofunctional variants received lower scores. There were 251 children (123 girls and 128 boys). Using the classic cut-offs (0.85 and 1.15), there were no statistically significant interactions between the neonatal groups and the dopamine genetic score. However, when changing the cut-offs, it is possible to see ranges of BWR that could be associated with vulnerability to poorer development according to the variation in the dopamine function. The classic birth weight cut-offs to define SGA and LGA newborns should be seen with caution, as depending on the outcome in question, the protocols for long-term follow up could be either too inclusive-therefore most costly, or unable to screen true vulnerabilities-and therefore ineffective to establish early interventions and primary prevention.

Molecular genetics and antisocial behavior: where do we stand?

PubMed

Iofrida, Caterina; Palumbo, Sara; Pellegrini, Silvia

2014-11-01

Over the last two decades, it has become increasingly evident that control of aggressive behavior is modulated by the individual genetic profile as well. Several candidate genes have been proposed to play a role in the risk to develop antisocial behavior, and distinct brain imaging studies have shown that specific cortical areas may be functionally and/or structurally impaired in impulsive violent subjects on the basis of their genotypes. In this paper, we review the findings regarding four polymorphisms-MAOA (Monoamine oxidase A) uVNTR, SLC6A4 (solute carrier family 6 (neurotransmitter transporter), member 4) 5HTTLPR, COMT (Catechol-O-methyltransferase) Val158Met and DRD4 (dopamine D4 receptor) VNTR 1-11-that all have been found to be associated with an increased vulnerability for antisocial and impulsive behavior in response to aversive environmental conditions. These results, however, have not been replicated by other studies, likely because of crucial methodological discrepancies, including variability in the criteria used to define antisocial behavior and assessment of environmental factors. Finally, it has been recently proposed that these genetic variants may actually increase the individual susceptibility not merely to the negative environmental factors, but to the positive ones as well. In this view, such alleles would play a wider modulatory role, by acting as "plasticity" rather than "vulnerability" genes. Overall, these findings have potential important implications that span well outside of neuroscience and psychiatry, to embrace ethics, philosophy, and the law itself, as they pose new challenges to the very notion of Free Will. Novel properly controlled studies that examine multi-allelic genetic profiles, rather than focusing on distinct single variants, will make it possible to achieve a clearer understanding of the molecular underpinnings of the nature by nurture interaction. © 2014 by the Society for Experimental Biology and Medicine.

How much of reinforcement learning is working memory, not reinforcement learning? A behavioral, computational, and neurogenetic analysis

PubMed Central

Collins, Anne G. E.; Frank, Michael J.

2012-01-01

Instrumental learning involves corticostriatal circuitry and the dopaminergic system. This system is typically modeled in the reinforcement learning (RL) framework by incrementally accumulating reward values of states and actions. However, human learning also implicates prefrontal cortical mechanisms involved in higher level cognitive functions. The interaction of these systems remains poorly understood, and models of human behavior often ignore working memory (WM) and therefore incorrectly assign behavioral variance to the RL system. Here we designed a task that highlights the profound entanglement of these two processes, even in simple learning problems. By systematically varying the size of the learning problem and delay between stimulus repetitions, we separately extracted WM-specific effects of load and delay on learning. We propose a new computational model that accounts for the dynamic integration of RL and WM processes observed in subjects' behavior. Incorporating capacity-limited WM into the model allowed us to capture behavioral variance that could not be captured in a pure RL framework even if we (implausibly) allowed separate RL systems for each set size. The WM component also allowed for a more reasonable estimation of a single RL process. Finally, we report effects of two genetic polymorphisms having relative specificity for prefrontal and basal ganglia functions. Whereas the COMT gene coding for catechol-O-methyl transferase selectively influenced model estimates of WM capacity, the GPR6 gene coding for G-protein-coupled receptor 6 influenced the RL learning rate. Thus, this study allowed us to specify distinct influences of the high-level and low-level cognitive functions on instrumental learning, beyond the possibilities offered by simple RL models. PMID:22487033

Dopamine and cognitive control: sex-by-genotype interactions influence the capacity to switch attention.

PubMed

Gurvich, C; Rossell, S L

2015-03-15

Cognitive performance in healthy persons varies widely between individuals. Sex differences in cognition are well reported, and there is an emerging body of evidence suggesting that the relationship between dopaminergic neurotransmission, implicated in many cognitive functions, is modulated by sex. Here, we examine the influence of sex and genetic variations along the dopaminergic pathway on aspects of cognitive control. A total of 415 healthy individuals, selected from an international consortium linked to Brain Research and Integrative Neuroscience Network (BRAINnet), were genotyped for two common and functional genetic variations of dopamine regulating genes: the catechol-O-methyltransferase [COMT] gene (rs4680) and the dopamine receptor D2 [DRD2] gene (rs6277). Cognitive measures were selected to explore sustained attention (using a continuous performance task), switching of attention (using a Trails B adaptation) and working memory (a visual computerised adaptation of digit span). While there were no main effects for genotype across any tasks, analyses revealed significant sex by genotype interactions for the capacity to switch attention. In relation to COMT, superior performance was noted in females with the Val/Val genotype and for DRD2, superior performance was seen for TT females and CC males. These findings highlight the importance of considering genetic variation in baseline dopamine levels in addition to sex, when considering the impact of dopamine on cognition in healthy populations. These findings also have important implications for the many neuropsychiatric disorders that implicate dopamine, cognitive changes and sex differences. Copyright © 2014 Elsevier B.V. All rights reserved.

Limited Associations of Dopamine System Genes With Alcohol Dependence and Related Traits in the Irish Affected Sib Pair Study of Alcohol Dependence (IASPSAD)

PubMed Central

Hack, Laura M.; Kalsi, Gursharan; Aliev, Fazil; Kuo, Po-Hsiu; Prescott, Carol A.; Patterson, Diana G.; Walsh, Dermot; Dick, Danielle M.; Riley, Brien P.; Kendler, Kenneth S.

2012-01-01

Background Over 50 years of evidence from research has established that the central dopaminergic reward pathway is likely involved in alcohol dependence (AD). Additional evidence supports a role for dopamine (DA) in other disinhibitory psychopathology, which is often comorbid with AD. Family and twin studies demonstrate that a common genetic component accounts for most of the genetic variance in these traits. Thus, DA-related genes represent putative candidates for the genetic risk that underlies not only AD but also behavioral disinhibition. Many linkage and association studies have examined these relationships with inconsistent results, possibly because of low power, poor marker coverage, and/or an inappropriate correction for multiple testing. Methods We conducted an association study on the products encoded by 10 DA-related genes (DRD1-D5, SLC18A2, SLC6A3, DDC, TH, COMT) using a large, ethnically homogeneous sample with severe AD (n = 545) and screened controls (n = 509). We collected genotypes from linkage disequilibrium (LD)-tagging single nucleotide polymorphisms (SNPs) and employed a gene-based method of correction. We tested for association with AD diagnosis in cases and controls and with a variety of alcohol-related traits (including age-at-onset, initial sensitivity, tolerance, maximum daily drinks, and a withdrawal factor score), disinhibitory symptoms, and a disinhibitory factor score in cases only. A total of 135 SNPs were genotyped using the Illumina GoldenGate and Taqman Assays-on-Demand protocols. Results Of the 101 SNPs entered into standard analysis, 6 independent SNPs from 5 DA genes were associated with AD or a quantitative alcohol-related trait. Two SNPs across 2 genes were associated with a disinhibitory symptom count, while 1 SNP in DRD5 was positive for association with the general disinhibitory factor score. Conclusions Our study provides evidence of modest associations between a small number of DA-related genes and AD as well as a range of alcohol-related traits and measures of behavioral disinhibition. While we did conduct gene-based correction for multiple testing, we did not correct for multiple traits because the traits are correlated. However, false-positive findings remain possible, so our results must be interpreted with caution. PMID:21083670

Biopsychosocial influence on shoulder pain: risk subgroups translated across preclinical and clinical prospective cohorts

PubMed Central

George, Steven Z.; Wallace, Margaret R.; Wu, Samuel S.; Moser, Michael W.; Wright, Thomas W.; Farmer, Kevin W.; Borsa, Paul A.; Parr, Jeffrey J.; Greenfield, Warren H.; Dai, Yunfeng; Li, Hua; Fillingim, Roger B.

2016-01-01

Tailored treatment based on individual risk factors is an area with promise to improve options for pain relief. Musculoskeletal pain has a biopsychosocial nature, and multiple factors should be considered when determining risk for chronic pain. This study investigated whether subgroups comprised genetic and psychological factors predicted outcomes in preclinical and clinical models of shoulder pain. Classification and regression tree analysis was performed for an exercise-induced shoulder injury cohort (n = 190) to identify high-risk subgroups, and a surgical pain cohort (n = 150) was used for risk validation. Questionnaires for fear of pain and pain catastrophizing were administered before injury and preoperatively. DNA collected from saliva was genotyped for a priori selected genes involved with pain modulation (COMT and AVPR1A) and inflammation (IL1B and TNF/LTA). Recovery was operationalized as a brief pain inventory rating of 0/10 for current pain intensity and <2/10 for worst pain intensity. Follow-up for the preclinical cohort was in daily increments, whereas follow-up for the clinical cohort was at 3, 6, and 12 months postoperatively. Risk subgroups comprised the COMT high pain sensitivity variant and either pain catastrophizing or fear of pain were predictive of heightened shoulder pain responses in the preclinical model. Further analysis in the clinical model identified the COMT high pain sensitivity variant and pain catastrophizing subgroup as the better predictor. Future studies will determine whether these findings can be replicated in other anatomical regions and whether personalized medicine strategies can be developed for this risk subgroup. PMID:25599310

A meta-analysis of eNOS and ACE gene polymorphisms and risk of pre-eclampsia in women.

PubMed

Shaik, A P; Sultana, A; Bammidi, V K; Sampathirao, K; Jamil, K

2011-10-01

A meta-analyses of endothelial nitric oxide synthase (eNOS) and angiotensin-converting enzyme (ACE) gene polymorphisms in pre-eclampsia was performed. We shortlisted 33 studies (17 for ACE; 16 for eNOS gene polymorphisms), of which 29 articles (16 for ACE and 15 for eNOS) were analysed. Overall, 1,620 cases with pre-eclampsia and 2,158 controls were analysed for intron 16 insertion-deletion polymorphism in ACE gene. A total of 1,610 subjects with pre-eclampsia and 2,875 controls were analysed for the Glu298Asp in eNOS gene. Overall, the random-effects odds ratio (OR) with Glu298Asp in eNOS gene was 0.958 (95% confidence intervals, CI 0.747-1.228, p > 0.05), and for the insertion-deletion/ACE polymorphism was 0.987 (95% CI 0.698-1.395, p > 0.05). Significant heterogeneity was observed in the studies that evaluated polymorphisms in ACE (Q value = 55.6; I(2) = 73; p value = 0.000); and eNOS (Q value = 37.2; I(2) = 62.4; p value = 0.001) polymorphisms. No significant risk of pre-eclampsia was observed in both eNOS and ACE genes with these polymorphisms.

COMT Val158Met and MTHFR C677T moderate risk of schizophrenia in response to childhood adversity.

PubMed

Debost, J-C; Debost, M; Grove, J; Mors, O; Hougaard, D M; Børglum, A D; Mortensen, P B; Petersen, L

2017-07-01

Mesolimbic dopamine sensitization has been hypothesized to be a mediating factor of childhood adversity (CA) on schizophrenia risk. Activity of catechol-O-methyltransferase (COMT) Val158Met increases mesolimbic dopamine signaling and may be further regulated by methylenetetrahydrofolate reductase (MTHFR) C677T. This study investigates the three-way interaction between CA, COMT, and MTHFR. We conducted a nested case-control study on individuals born after 1981, linking population-based registers to study the three-way interaction. We included 1699 schizophrenia cases and 1681 controls, and used conditional logistic regression to report incidence rate ratios (IRRs). Childhood adversity was robustly associated with schizophrenia. No main genetic effects were observed. MTHFR C677T increased schizophrenia risk in a dose-dependent manner per MTHFR T allele (P = 0.005) consequent upon CA exposure. After inclusion of the significant (P = 0.03) COMT × MTHFR × CA interaction, the risk was further increased per high-activity COMT Val allele. Hence, exposed COMT Val/Val and MTHFR T/T carriers had an IRR of 2.76 (95% CI, 1.66-4.61). Additional adjustments for ancestry and parental history of mental illness attenuated the results with the interaction being only marginally significant. MTHFR C677T and COMT Val158Met interact with CA to increase risk of schizophrenia. © 2017 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

The role of COMT and plasma proline in the variable penetrance of autistic spectrum symptoms in 22q11.2 deletion syndrome.

PubMed

Hidding, E; Swaab, H; de Sonneville, L M J; van Engeland, H; Vorstman, J A S

2016-11-01

This paper examines how COMT 158 genotypes and plasma proline levels are associated with variable penetrance of social behavioural and social cognitive problems in 22q11.2 deletion syndrome (22q11DS). Severity of autistic spectrum symptoms of 45 participants with 22q11DS was assessed using the Autism Diagnostic Interview Revised. Face and facial emotion recognition was evaluated using standardized computer-based test-paradigms. Associations with COMT 158 genotypes and proline levels were examined. High proline levels and poor face recognition in individuals with the COMT MET allele, and poor facial emotion recognition, explained almost 50% of the variance in severity of autism symptomatology in individuals with 22q11DS. High proline levels and a decreased capacity to break down dopamine as a result of the COMT MET variant are both relevant in the expression of the social phenotype in patients. This epistatic interaction effect between the COMT 158 genotype and proline on the expression of social deficits in 22q11DS shows how factors other than the direct effects of the deletion itself can modulate the penetrance of associated cognitive and behavioural outcomes. These findings are not only relevant to our insight into 22q11DS, but also provide a model to better understand the phenomenon of variable penetrance in other pathogenic genetic variants. © 2016 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Folate and Breast Cancer: Role of Intake, Blood Levels, and Metabolic Gene Polymorphisms

DTIC Science & Technology

2005-07-01

folate, and metabolic gene polymorphisms in relation to breast cancer risk: Months 1-19. b. Prepare blood samples for relevant assays: Months 1-19... gene polymorphism assays among the 184 cases and matched controls. The folate assays are on-going at this time. DNA assays will commence in the... methotrexate . Ann Oncol 13: 1915–1918, 2002 13. Toffoli G, Veronesi A, Boiocchi M, Crivellari D: MTHFR gene polymorphism and severe toxicity during

Polymorphisms of three genes (ACE, AGT and CYP11B2) in the renin-angiotensin-aldosterone system are not associated with blood pressure salt sensitivity: A systematic meta-analysis.

PubMed

Sun, Jiahong; Zhao, Min; Miao, Song; Xi, Bo

2016-01-01

Many studies have suggested that polymorphisms of three key genes (ACE, AGT and CYP11B2) in the renin-angiotensin-aldosterone system (RAAS) play important roles in the development of blood pressure (BP) salt sensitivity, but they have revealed inconsistent results. Thus, we performed a meta-analysis to clarify the association. PubMed and Embase databases were searched for eligible published articles. Fixed- or random-effect models were used to pool odds ratios and 95% confidence intervals based on whether there was significant heterogeneity between studies. In total, seven studies [237 salt-sensitive (SS) cases and 251 salt-resistant (SR) controls] for ACE gene I/D polymorphism, three studies (130 SS cases and 221 SR controls) for AGT gene M235T polymorphism and three studies (113 SS cases and 218 SR controls) for CYP11B2 gene C344T polymorphism were included in this meta-analysis. The results showed that there was no significant association between polymorphisms of these three polymorphisms in the RAAS and BP salt sensitivity under three genetic models (all p > 0.05). The meta-analysis suggested that three polymorphisms (ACE gene I/D, AGT gene M235T, CYP11B2 gene C344T) in the RAAS have no significant effect on BP salt sensitivity.

HOTAIR gene polymorphisms contribute to increased neuroblastoma susceptibility in Chinese children.

PubMed

Yang, Xu; He, Jing; Chang, Yitian; Luo, Annie; Luo, Ailing; Zhang, Jiao; Zhang, Ruizhong; Xia, Huimin; Xu, Ling

2018-06-15

Neuroblastoma is the most frequently diagnosed extracranial solid tumor in children. Previous studies have shown that single-nucleotide polymorphisms in some genes are associated with the risk of multiple cancers, including neuroblastoma. Although Hox transcript antisense intergenic RNA (HOTAIR) gene polymorphisms have been investigated in a variety of cancers, to the authors' knowledge the relationships between HOTAIR gene polymorphisms and neuroblastoma susceptibility have not been reported to date. The objective of the current study was to evaluate the correlation between HOTAIR gene polymorphisms and neuroblastoma risk in Chinese children. The authors genotyped 6 polymorphisms (rs920778 A>G, rs12826786 C>T, rs4759314 A>G, rs7958904 G>C, rs874945 C>T, and rs1899663 C>A) of the HOTAIR gene in 2 Chinese populations including 393 neuroblastoma cases and 812 healthy controls. The strength of the associations was evaluated using odds ratios and 95% confidence intervals. Further stratification analyses were conducted to explore the association between the HOTAIR gene polymorphisms rs12826786 C>T, rs874945 C>T, and rs1899663 C>A with neuroblastoma susceptibility in terms of age, sex, clinical stage of disease, and sites of origin. The authors found that the rs12826786 C>T (P =.013), rs874945 C>T (P =.020), and rs1899663 C>A (P =.029) polymorphisms were significantly associated with increased neuroblastoma risk. In stratification analyses, these associations were more predominant in females and among patients with tumor in the retroperitoneal region or mediastinum. The remaining 3 polymorphisms were not found to be related to neuroblastoma susceptibility. The results of the current study verified that HOTAIR gene polymorphisms are associated with increased neuroblastoma risk and suggest that HOTAIR gene polymorphisms might be a potential biomarker for neuroblastoma susceptibility. Cancer 2018;124:2599-606. © 2018 American Cancer Society. © 2018 American Cancer Society.

In silico screening of the chicken genome for overlaps between genomic regions: microRNA genes, coding and non-coding transcriptional units, QTL, and genetic variations.

PubMed

Zorc, Minja; Kunej, Tanja

2016-05-01

MicroRNAs (miRNAs) are a class of non-coding RNAs involved in posttranscriptional regulation of target genes. Regulation requires complementarity between target mRNA and the mature miRNA seed region, responsible for their recognition and binding. It has been estimated that each miRNA targets approximately 200 genes, and genetic variability of miRNA genes has been reported to affect phenotypic variability and disease susceptibility in humans, livestock species, and model organisms. Polymorphisms in miRNA genes could therefore represent biomarkers for phenotypic traits in livestock animals. In our previous study, we collected polymorphisms within miRNA genes in chicken. In the present study, we identified miRNA-related genomic overlaps to prioritize genomic regions of interest for further functional studies and biomarker discovery. Overlapping genomic regions in chicken were analyzed using the following bioinformatics tools and databases: miRNA SNiPer, Ensembl, miRBase, NCBI Blast, and QTLdb. Out of 740 known pre-miRNA genes, 263 (35.5 %) contain polymorphisms; among them, 35 contain more than three polymorphisms The most polymorphic miRNA genes in chicken are gga-miR-6662, containing 23 single nucleotide polymorphisms (SNPs) within the pre-miRNA region, including five consecutive SNPs, and gga-miR-6688, containing ten polymorphisms including three consecutive polymorphisms. Several miRNA-related genomic hotspots have been revealed in chicken genome; polymorphic miRNA genes are located within protein-coding and/or non-coding transcription units and quantitative trait loci (QTL) associated with production traits. The present study includes the first description of an exonic miRNA in a chicken genome, an overlap between the miRNA gene and the exon of the protein-coding gene (gga-miR-6578/HADHB), and the first report of a missense polymorphism located within a mature miRNA seed region. Identified miRNA-related genomic hotspots in chicken can serve researchers as a starting point for further functional studies and association studies with poultry production and health traits and the basis for systematic screening of exonic miRNAs and missense/miRNA seed polymorphisms in other genomes.

Association of ACE Gene I/D polymorphism with migraine in Kashmiri population.

PubMed

Wani, Irfan Yousuf; Sheikh, Saleem; Shah, Zafar Amin; Pandith, Arshid A; Wani, Mushtaq; Asimi, Ravouf; Wani, Maqbool; Sheikh, Shahnawaz; Mehraj, Iqra

2016-01-01

Migraine is a complex, recurrent headache disorder that is one of the most common complaints in neurology practice. The role of various genes in its pathogenesis is being studied. We did this study to see whether an association exists between ACE gene I/D polymorphism and migraine in our region. The study included 100 patients diagnosed with migraine and 121 healthy controls. The study subject were age and gender matched. The analysis was based on Polymerase Chain Reaction (PCR) and included following steps: DNA extraction from blood, PCR and Restriction Fragment Length Polymorphism (RFLP). Out of 100 cases, 69 were females and 31 were males. Fifty-seven were having migraine without aura and 43 had migraine with aura. 45 of the cases had II polymorphism, 40 had ID polymorphism and 15 had DD polymorphism in ACE gene. We were not able to find a statistically significant association between ACE gene I/D polymorphism with migraine. The reason for difference in results between our study and other studies could be because of different ethnicity in study populations. So a continuous research is needed in this regard in order to find the genes and different polymorphism that increase the susceptibility of Kashmiri population to migraine.

Genomic polymorphism, recombination, and linkage disequilibrium in human major histocompatibility complex-encoded antigen-processing genes.

PubMed Central

van Endert, P M; Lopez, M T; Patel, S D; Monaco, J J; McDevitt, H O

1992-01-01

Recently, two subunits of a large cytosolic protease and two putative peptide transporter proteins were found to be encoded by genes within the class II region of the major histocompatibility complex (MHC). These genes have been suggested to be involved in the processing of antigenic proteins for presentation by MHC class I molecules. Because of the high degree of polymorphism in MHC genes, and previous evidence for both functional and polypeptide sequence polymorphism in the proteins encoded by the antigen-processing genes, we tested DNA from 27 consanguineous human cell lines for genomic polymorphism by restriction fragment length polymorphism (RFLP) analysis. These studies demonstrate a strong linkage disequilibrium between TAP1 and LMP2 RFLPs. Moreover, RFLPs, as well as a polymorphic stop codon in the telomeric TAP2 gene, appear to be in linkage disequilibrium with HLA-DR alleles and RFLPs in the HLA-DO gene. A high rate of recombination, however, seems to occur in the center of the complex, between the TAP1 and TAP2 genes. Images PMID:1360671

No evidence of association between NOD2/CARD15 gene polymorphism and atherosclerotic events after renal transplantation

PubMed Central

Courivaud, Cécile; Ferrand, Christophe; Deschamps, Marina; Tiberghien, Pierre; Chalopin, Jean-Marc; Duperrier, Anne; Saas, Philippe; Ducloux, Didier

2006-01-01

Stable renal transplant recipients (RTR) display high rates of atherosclerotic events (AE). Innate immunity and especially vascular inflammation play a role in the pathogenesis of atherosclerosis. It is illustrated both by an increased occurrence of post-renal transplant cardiovascular events in patients with elevated levels of C-reactive protein and by a correlation between post-transplant AE and Toll-like receptor-4 Asp299Gly polymorphism. Here, we analyze the influence NOD2/CARD15 gene polymorphism since NOD2 can modulate macrophage pro-inflammatory activity and macrophage is present in early atherosclerotic lesions. The incidence of single nucleotide polymorphism (SNP) in the three major polymorphic region of NOD2 gene (SNP8, SNP12 and SNP13) was assessed in 182 RTR and the correlation between such polymorphism and the development of AE was analyzed. No correlation was observed between NOD2 gene polymorphism and the occurrence of AE after renal transplantation. NOD2 gene polymorphism thus does not appear to influence cardiovascular complications in RTR. PMID:16641610

Infraspecific DNA methylation polymorphism in cotton (Gossypium hirsutum L.).

PubMed

Keyte, Anna L; Percifield, Ryan; Liu, Bao; Wendel, Jonathan F

2006-01-01

Cytosine methylation is important in the epigenetic regulation of gene expression and development in plants and has been implicated in silencing duplicate genes after polyploid formation in several plant groups. Relatively little information exists, however, on levels and patterns of methylation polymorphism (MP) at homologous loci within species. Here we explored the levels and patterns of methylation-polymorphism diversity at CCGG sites within allotetraploid cotton, Gossypium hirsutum, using a methylation-sensitive amplified fragment length polymorphism screen and a selected set of 20 G. hirsutum accessions for which we have information on genetic polymorphism levels and relationships. Methylation and MP exist at high levels within G. hirsutum: of 150 HpaII/MspI sites surveyed, 48 were methylated at the inner cytosine (32%) and 32 of these were polymorphic (67%). Both these values are higher than comparable measures of genetic diversity using restriction fragment length polymorphisms. The high percentage of methylation-polymorphic sites and potential relationship to gene expression underscore the potential significance of MP within and among populations. We speculate that biased correlation of methylation-polymorphic sites and genes in cotton may be a consequence of polyploidy and the attendant doubling of all genes.

Transgenic switchgrass ( Panicum virgatum L.) targeted for reduced recalcitrance to bioconversion: A two-year comparative analysis of field-grown lines modified for target gene or genetic element expression

DOE PAGES

Dumitrache, Alexandru; Natzke, Jace; Rodriguez, Jr., Miguel; ...

2016-11-18

Five different types of transgenic ( GAUT4, miRNA, MYB4, COMT and FPGS) Panicum virgatum L. (switchgrass) were grown in a field in Knoxville, Tenn., USA over two consecutive years between 2011 and 2015 in separate experiments. Clonal replicates were established (year-one) and produced much greater biomass during the second year. After each growing season the above ground biomass was analyzed for cell wall sugars and for recalcitrance to enzymatic digestibility, and biofuel using a separate hydrolysis and fermentation (SHF) screen. Here, each transgenic event and control had more glucan, xylan and less ethanol (g/g basis) from the second year ofmore » growth relative to the first year plants. There was no correlation between plant carbohydrate content and biofuel production. In each of cell wall-targeted transgenics, GAUT4, MYB4, COMT and FPGS, the second year of growth resulted in increased carbohydrate abundance (up to 12%) and reduced recalcitrance through higher ethanol yields (up to 21%) over the non-transgenic control plants.« less

Transgenic switchgrass ( Panicum virgatum L.) targeted for reduced recalcitrance to bioconversion: A two-year comparative analysis of field-grown lines modified for target gene or genetic element expression

DOE Office of Scientific and Technical Information (OSTI.GOV)

Dumitrache, Alexandru; Natzke, Jace; Rodriguez, Jr., Miguel

Five different types of transgenic ( GAUT4, miRNA, MYB4, COMT and FPGS) Panicum virgatum L. (switchgrass) were grown in a field in Knoxville, Tenn., USA over two consecutive years between 2011 and 2015 in separate experiments. Clonal replicates were established (year-one) and produced much greater biomass during the second year. After each growing season the above ground biomass was analyzed for cell wall sugars and for recalcitrance to enzymatic digestibility, and biofuel using a separate hydrolysis and fermentation (SHF) screen. Here, each transgenic event and control had more glucan, xylan and less ethanol (g/g basis) from the second year ofmore » growth relative to the first year plants. There was no correlation between plant carbohydrate content and biofuel production. In each of cell wall-targeted transgenics, GAUT4, MYB4, COMT and FPGS, the second year of growth resulted in increased carbohydrate abundance (up to 12%) and reduced recalcitrance through higher ethanol yields (up to 21%) over the non-transgenic control plants.« less

Potential of genetically engineered hybrid poplar for pyrolytic production of bio-based phenolic compounds.

PubMed

Toraman, Hilal E; Vanholme, Ruben; Borén, Eleonora; Vanwonterghem, Yumi; Djokic, Marko R; Yildiz, Guray; Ronsse, Frederik; Prins, Wolter; Boerjan, Wout; Van Geem, Kevin M; Marin, Guy B

2016-05-01

Wild-type and two genetically engineered hybrid poplar lines were pyrolyzed in a micro-pyrolysis (Py-GC/MS) and a bench scale setup for fast and intermediate pyrolysis studies. Principal component analysis showed that the pyrolysis vapors obtained by micro-pyrolysis from wood of caffeic acid O-methyltransferase (COMT) and caffeoyl-CoA O-methyltransferase (CCoAOMT) down-regulated poplar trees differed significantly from the pyrolysis vapors obtained from non-transgenic control trees. Both fast micro-pyrolysis and intermediate pyrolysis of transgenic hybrid poplars showed that down-regulation of COMT can enhance the relative yield of guaiacyl lignin-derived products, while the relative yield of syringyl lignin-derived products was up to a factor 3 lower. This study indicates that lignin engineering via genetic modifications of genes involved in the phenylpropanoid and monolignol biosynthetic pathways can help to steer the pyrolytic production of guaiacyl and syringyl lignin-derived phenolic compounds such as guaiacol, 4-methylguaiacol, 4-ethylguaiacol, 4-vinylguaiacol, syringol, 4-vinylsyringol, and syringaldehyde present in the bio-oil. Copyright © 2016 Elsevier Ltd. All rights reserved.

[Prevalence of gene polymorphisms associated with immune-dependent diseases in the populations of North Eurasia].

PubMed

Cherednichenko, A A; Trifonova, E A; Vagaitseva, K V; Bocharova, A V; Varzari, A M; Radzhabov, M O; Stepanov, V A

2015-01-01

The data on distribution of genetic diversity in gene polymorphisms associated with autoimmune and allergic diseases and with regulation of immunoglobulin E and cytokines levels in 26 populations of the Northern Eurasia is presented. Substantial correlation between the values of average expected heterozygosity by 44 gene polymorphisms with climatic and geographical factors has not been revealed. Clustering of population groups in correspondence with their geographic locations is observed. The degree of gene differentiation among populations and the selective neutrality of gene polymorphisms have been assessed. The results of our work evidence the substantial genetic diversity and differentiation of human populations by studied genes.

Communication Satellites, 1958-1992

DTIC Science & Technology

1991-12-31

Communnic’ation Satellite Sy’stemls per 90-0786,13th AIAA ilnternational Commiun iation Satel- con1 r’ne ( March 1986). lite Si’stems Comt erence (March 1990). 52... Comt - 13. Aviation Week & Space Technology: (3 June 1974), p. 18: (23 munications: ICC 󈨏 (June 1975). September 1974). p. 23: (30 September 1974). p...6. I1. International Con ’rent e (oi Comt 1Uif 1 - S. P. Lucinbuhl and H. Salomion. ’"Telecom I Diuital Transmiis- (’tilonls: /CC’’S6 (June 1986

Sequential processing deficits in schizophrenia: relationship to neuropsychology and genetics.

PubMed

Hill, S Kristian; Bjorkquist, Olivia; Carrathers, Tarra; Roseberry, Jarett E; Hochberger, William C; Bishop, Jeffrey R

2013-12-01

Utilizing a combination of neuropsychological and cognitive neuroscience approaches may be essential for characterizing cognitive deficits in schizophrenia and eventually assessing cognitive outcomes. This study was designed to compare the stability of select exemplars for these approaches and their correlations in schizophrenia patients with stable treatment and clinical profiles. Reliability estimates for serial order processing were comparable to neuropsychological measures and indicate that experimental serial order processing measures may be less susceptible to practice effects than traditional neuropsychological measures. Correlations were moderate and consistent with a global cognitive factor. Exploratory analyses indicated a potentially critical role of the Met allele of the Catechol-O-methyltransferase (COMT) Val158Met polymorphism in externally paced sequential recall. Experimental measures of serial order processing may reflect frontostriatal dysfunction and be a useful supplement to large neuropsychological batteries. © 2013.

Sequential Processing Deficits in Schizophrenia: Relationship to Neuropsychology and Genetics

PubMed Central

Hill, S. Kristian; Bjorkquist, Olivia; Carrathers, Tarra; Roseberry, Jarett E.; Hochberger, William C.; Bishop, Jeffrey R.

2014-01-01

Utilizing a combination of neuropsychological and cognitive neuroscience approaches may be essential for characterizing cognitive deficits in schizophrenia and eventually assessing cognitive outcomes. This study was designed to compare the stability of select exemplars for these approaches and their correlations in schizophrenia patients with stable treatment and clinical profiles. Reliability estimates for serial order processing were comparable to neuropsychological measures and indicate that experimental serial order processing measures may be less susceptible to practice effects than traditional neuropsychological measures. Correlations were moderate and consistent with a global cognitive factor. Exploratory analyses indicated a potentially critical role of the Met allele of the Catechol-O-methyltransferase (COMT) Val158Met polymorphism in externally paced sequential recall. Experimental measures of serial order processing may reflect frontostriatal dysfunction and be a useful supplement to large neuropsychological batteries. PMID:24119464

No association of the neuropeptide Y (Leu7Pro) and ghrelin gene (Arg51Gln, Leu72Met, Gln90Leu) single nucleotide polymorphisms with eating disorders.

PubMed

Kindler, Jochen; Bailer, Ursula; de Zwaan, Martina; Fuchs, Karoline; Leisch, Friedrich; Grün, Bettina; Strnad, Alexandra; Stojanovic, Mirjana; Windisch, Julia; Lennkh-Wolfsberg, Claudia; El-Giamal, Nadja; Sieghart, Werner; Kasper, Siegfried; Aschauer, Harald

2011-06-01

Genetic factors likely contribute to the biological vulnerability of eating disorders. Case-control association study on one neuropeptide Y gene (Leu7Pro) polymorphism and three ghrelin gene (Arg51Gln, Leu72Met and Gln90Leu) polymorphisms. 114 eating disorder patients (46 with anorexia nervosa, 30 with bulimia nervosa, 38 with binge eating disorder) and 164 healthy controls were genotyped. No differences were detected between patients and controls for any of the four polymorphisms in allele frequency and genotype distribution (P > 0.05). Allele frequencies and genotypes had no significant influence on body mass index (P > 0.05) in eating disorder patients. Positive findings of former case-control studies of associations between ghrelin gene polymorphisms and eating disorders could not be replicated. Neuropeptide Y gene polymorphisms have not been investigated in eating disorders before.

The effect of a promoter polymorphism on the transcription of nitric oxide synthase 1 and its relevance to Parkinson's disease.

PubMed

Rife, Terrie; Rasoul, Bareza; Pullen, Nicholas; Mitchell, David; Grathwol, Kristen; Kurth, Janice

2009-08-01

Transcriptional changes of the enzyme nitric oxide synthase I (NOS1) are believed to play a role in the development of many diseases. The gene for NOS1 has 12 alternative first exons (1A-1L). The 1F exon is one of the most highly utilized first exons in the brain and has a polymorphism ((TG)(m)TA(TG)(n)) located in its promoter region. The polymorphism's length has been suggested to affect NOS1 transcription and play a role in Parkinson's disease (PD); however, the actual influence of the polymorphism on NOS1 transcription has not been studied. To better characterize the links of the polymorphism with PD, a genotyping study was done comparing polymorphism length among 170 PD patients and 150 age-matched controls. The pattern of changes between the two group's allele frequencies shows statistical significance (P = 0.0359). The smallest polymorphism sizes are more predominant among PD patients than controls. To study the effects of this polymorphism on NOS1 gene transcription, reporter gene constructs were made by cloning the NOS1 1F promoter with polymorphism lengths of either 42, 54, or 62 bp in front of the luciferase gene and transfecting them into HeLa or Sk-N-MC cells. NOS1-directed reporter gene constructs with the 62-bp polymorphism increased transcription of luciferase 2.2-fold in HeLa and 1.8-fold in Sk-N-MC cells compared with reporter gene constructs with the 42-bp polymorphism. These data suggest that if smaller polymorphism size contributes to the higher NOS1 levels in PD patients, an as yet unknown transcriptional mechanism is required. Copyright 2009 Wiley-Liss, Inc.

[Association of muscle segment homeobox gene 1 polymorphisms with nonsyndromic cleft lip with or without cleft palate].

PubMed

Zhang, Li; Tang, Jun-Ling; Liang, Shang-Zheng

2008-06-01

Muscle segment homeobox gene (MSX)1 has been proposed as a gene in which mutations may contribute to nonsyndromic cleft lip with or without cleft palate (NSCL/P). To study MSX1 polymorphisms in NSCL/ P by means of polymerase chain reaction-single-strand conformation polymorphism (PCR-SSCP), and investigate the association of MSX1 exons 1 polymorphisms with NSCL/P. DNA were extracted from blood samples from NSCL/P and unrelated normal subjects. Genome DNA from peripheral leukocyte with these blood samples were extracted, which was used as template to amplify desired gene fragment of MSX1 exons 1 by means of polymerase chain reaction (PCR). The PCR products were examined by single-strand conformation polymorphism (SSCP). The MSX1 exons 1 polymorphisms were examined by sequencing if mutations were found. MSX1 genes of exon 1 mutation was not been found in the NSCL/P and unrelated normal subjects by SSCP. No correlation between MSX1 exon 1 and NSCL/P was found. MSX1 exon 1 may not be a key gene (susceptibility gene) in NSCL/P.

Association of neonatal necrotizing enterocolitis with myeloid differentiation-2 and GM2 activator protein genetic polymorphisms.

PubMed

Zhou, Wei; Yuan, Weiming; Huang, Longguang; Wang, Ping; Rong, Xiao; Tang, Juan

2015-07-01

The aim of the present study was to investigate the association of neonatal necrotizing enterocolitis (NEC) with myeloid differentiation-(MD-2) and GM2 activator protein (GM2A) genetic polymorphisms. Gene resequencing of the MD-2 and GM2A gene exons was performed on 42 neonates, diagnosed with NEC (NEC group), as well as in the rs11465996 locus, located in the MD-2 gene promoter region. The aim was to detect the genetic polymorphisms present in the neonates with NEC and compare the functional polymorphic loci with 83 neonates without NEC (control group), who had been born during the same period. A polymorphic locus with abnormal frequency was detected in the exon region of the MD-2 gene. In the NEC group, the frequency of genotypes carrying the low frequency allele (G) in the rs11465996 locus (MD-2 promoter region) was significantly higher compared with the control group (χ(2)=4.388, P=0.036). Furthermore, the frequencies of genotypes carrying the low frequency A and C alleles in the rs1048719 (GM2A gene exon 1) and rs2075783 loci (GM2A intron), respectively, were significantly higher in the NEC group compared with the control group (χ(2)=4.316, P=0.038; and χ(2)=13.717, P=0.000, respectively). In addition, the rs11465996 polymorphism in the MD-2 gene promoter region was found to be associated with the severity of NEC. Furthermore, the rs2075783 polymorphism in the GM2A gene exon 1 and the rs1048719 polymorphism in the intron region of this gene, were associated with the occurrence of NEC. The present study demonstrated that gene polymorphisms of MD-2 and GM2A were associated with the occurrence or severity of NEC; however, further in-depth exploration is required to clarify the associations between genetic predispositions to polymorphisms, and NEC.

Association study of interferon gamma (IFN-γ) +874T/A gene polymorphism in patients with paranoid schizophrenia.

PubMed

Paul-Samojedny, Monika; Owczarek, Aleksander; Suchanek, Renata; Kowalczyk, Malgorzata; Fila-Danilow, Anna; Borkowska, Paulina; Kucia, Krzysztof; Kowalski, Jan

2011-03-01

Schizophrenia is a multifactorial disease with changes affecting the immune system. Dysregulation of the cytokine network in schizophrenia has been well documented. Such changes may occur due to disturbances in cytokine levels that are linked to polymorphisms of cytokine genes. However, research in the role of cytokine gene polymorphisms in schizophrenia has been surprisingly scanty. The aim of this study was to identify, in a case control study, whether polymorphism of IFN-γ gene is a risk factor for the development of paranoid schizophrenia. To the best of our knowledge, this is the first study that examines the association between the IFN-γ gene polymorphism and psychopathological symptoms in patients with paranoid schizophrenia. Polymorphism of IFN-γ (+874T/A, rs 62559044) in schizophrenic patients (n=179), as well as healthy individuals (n=196), both Polish residents, was genotyped using AS-PCR method. Of note, when analyzing the results, we took into consideration the gender of studied individuals. Surprisingly, a single-nucleotide polymorphism in the first intron of the IFN-γ gene was found to be associated with paranoid schizophrenia in males, but not in females. The presence of allele A at position +874 in the IFN-γ gene correlates with 1.66-fold higher risk of paranoid schizophrenia development in males. Differences in the genotypes may have an important role in determining the level of I gene transcription. Because other polymorphisms have been demonstrated to influence IFN-γ transcription, further analysis is necessary to clarify the role of this gene in the pathogenesis of paranoid schizophrenia.

Metabolic Disposition of Luteolin Is Mediated by the Interplay of UDP-Glucuronosyltransferases and Catechol-O-Methyltransferases in Rats.

PubMed

Wang, Liping; Chen, Qingwei; Zhu, Lijun; Li, Qiang; Zeng, Xuejun; Lu, Linlin; Hu, Ming; Wang, Xinchun; Liu, Zhongqiu

2017-03-01

Luteolin partially exerts its biologic effects via its metabolites catalyzed by UDP-glucuronosyltransferases (UGTs) and catechol-O-methyltransferases (COMTs). However, the interplay of UGTs and COMTs in mediating luteolin disposition has not been well clarified. In this study, we investigated the glucuronidation and methylation pathways of luteolin mediated by the interplay of UGTs and COMTs in vivo and in vitro. A total of nine luteolin metabolites was detected in rat plasma and bile by liquid chromatography-tandem mass spectrometry, namely, three glucuronides, two methylated metabolites, and four methylated glucuronides. Luteolin-3'-glucuronide (Lut-3'-G) exhibited the highest systemic exposure among these metabolites. Kinetics studies in rat liver S9 fractions suggested two pathways, as follows: 1) Luteolin was glucuronidated to luteolin-7-glucuronide, luteolin-4'-glucuronide, and Lut-3'-G by UGTs, and then Lut-7-G was methylated to chrysoeriol-7-glucuronide and diosmetin-7-glucuronide by COMTs. 2) Alternatively, luteolin was methylated to chrysoeriol and diosmetin by COMTs, and then chrysoeriol and diosmetin were glucuronidated by UGTs to their respective glucuronides. The methylation rate of luteolin was significantly increased by the absence of glucuronidation, whereas the glucuronidation rate was increased by the absence of methylation, but to a lesser extent. In conclusion, two pathways mediated by the interplay of UGTs and COMTs are probably involved in the metabolic disposition of luteolin. The glucuronidation and methylation of luteolin compensate for each other, although glucuronidation is the predominant pathway. Copyright © 2017 by The American Society for Pharmacology and Experimental Therapeutics.

Clinical study on gastric cancer susceptibility genes IL-10-1082 and TNF-α.

PubMed

Yu, T; Lu, Q; Ou, X L; Cao, D Z; Yu, Q

2014-12-19

TNF 308 gene polymorphism and IL-10 polymorphism provided evidence in diagnosing some types of cancer. We aimed to explore the relation of gene polymorphism with gastric cancer. A total of 360 cases of gastric cancer patients were included in the study. The genotypes GG, GA, and AA of the interleukin-10-1082 gene (IL-10-1082) and the tumor necrosis factor-alpha gene (TNF-α) 308 polymorphism were examined by chromogenic detection. Three hundred healthy individuals' gene as control group were also examined. The GA 308 genotype of TNF-α differed significantly between the control group and the gastric cancer group (X(2) = 9.32, P < 0.05). Genotype frequencies of A/A (17.2%), A/G (26.2%), and G/G (9.1%) of the IL-10-1082 gene polymorphism in the gastric cancer group differed significantly compared to those of the control group (X(2) = 20.32, P < 0.05). The IL-10-1082 gene and the GA 308 genotype of the TNF-α gene were found to be susceptibility genes for gastric cancer.

Variability in Dopamine Genes Dissociates Model-Based and Model-Free Reinforcement Learning.

PubMed

Doll, Bradley B; Bath, Kevin G; Daw, Nathaniel D; Frank, Michael J

2016-01-27

Considerable evidence suggests that multiple learning systems can drive behavior. Choice can proceed reflexively from previous actions and their associated outcomes, as captured by "model-free" learning algorithms, or flexibly from prospective consideration of outcomes that might occur, as captured by "model-based" learning algorithms. However, differential contributions of dopamine to these systems are poorly understood. Dopamine is widely thought to support model-free learning by modulating plasticity in striatum. Model-based learning may also be affected by these striatal effects, or by other dopaminergic effects elsewhere, notably on prefrontal working memory function. Indeed, prominent demonstrations linking striatal dopamine to putatively model-free learning did not rule out model-based effects, whereas other studies have reported dopaminergic modulation of verifiably model-based learning, but without distinguishing a prefrontal versus striatal locus. To clarify the relationships between dopamine, neural systems, and learning strategies, we combine a genetic association approach in humans with two well-studied reinforcement learning tasks: one isolating model-based from model-free behavior and the other sensitive to key aspects of striatal plasticity. Prefrontal function was indexed by a polymorphism in the COMT gene, differences of which reflect dopamine levels in the prefrontal cortex. This polymorphism has been associated with differences in prefrontal activity and working memory. Striatal function was indexed by a gene coding for DARPP-32, which is densely expressed in the striatum where it is necessary for synaptic plasticity. We found evidence for our hypothesis that variations in prefrontal dopamine relate to model-based learning, whereas variations in striatal dopamine function relate to model-free learning. Decisions can stem reflexively from their previously associated outcomes or flexibly from deliberative consideration of potential choice outcomes. Research implicates a dopamine-dependent striatal learning mechanism in the former type of choice. Although recent work has indicated that dopamine is also involved in flexible, goal-directed decision-making, it remains unclear whether it also contributes via striatum or via the dopamine-dependent working memory function of prefrontal cortex. We examined genetic indices of dopamine function in these regions and their relation to the two choice strategies. We found that striatal dopamine function related most clearly to the reflexive strategy, as previously shown, and that prefrontal dopamine related most clearly to the flexible strategy. These findings suggest that dissociable brain regions support dissociable choice strategies. Copyright © 2016 the authors 0270-6474/16/361211-12$15.00/0.

Early intervention following trauma may mitigate genetic risk for PTSD in civilians: a pilot prospective emergency department study.

PubMed

Rothbaum, Barbara O; Kearns, Megan C; Reiser, Emily; Davis, Jennifer S; Kerley, Kimberly A; Rothbaum, Alex O; Mercer, Kristina B; Price, Matthew; Houry, Debra; Ressler, Kerry J

2014-12-01

Civilian posttraumatic stress disorder (PTSD) and combat PTSD are major public health concerns. Although a number of psychosocial risk factors have been identified related to PTSD risk, there are no accepted, robust biological predictors that identify who will develop PTSD or who will respond to early intervention following trauma. We wished to examine whether genetic risk for PTSD can be mitigated with an early intervention. 65 emergency department patients recruited in 2009-2010 at Grady Memorial Hospital in Atlanta, Georgia, who met criterion A of DSM-IV PTSD received either 3 sessions of an exposure intervention, beginning in the emergency department shortly after trauma exposure or assessment only. PTSD symptoms were assessed 4 and 12 weeks after trauma exposure. A composite additive risk score was derived from polymorphisms in 10 previously identified genes associated with stress-response (ADCYAP1R1, COMT, CRHR1, DBH, DRD2, FAAH, FKBP5, NPY, NTRK2, and PCLO), and gene x treatment effects were examined. The intervention included 3 sessions of imaginal exposure to the trauma memory and additional exposure homework. The primary outcome measure was the PTSD Symptom Scale-Interview Version or DSM-IV-based PTSD diagnosis in patients related to genotype and treatment group. A gene x intervention x time effect was detected for individual polymorphisms, in particular the PACAP receptor, ADCYAP1R1, as well as with a combined genotype risk score created from independent SNP markers. Subjects who did not receive treatment had higher symptoms than those who received intervention. Furthermore, subjects with the "risk" genotypes who did not receive intervention had higher PTSD symptoms compared to those with the "low-risk" or "resilience" genotypes or those who received intervention. Additionally, PTSD symptoms correlated with level of genetic risk at week 12 (P < .005) in the assessment-only group, but with no relationship in the intervention group, even after controlling for age, sex, race, education, income, and childhood trauma. Using logistic regression, the number of risk alleles was significantly associated with likelihood of PTSD diagnosis at week 12 (P < .05). This pilot prospective study suggests that combined genetic variants may serve to predict those most at risk for developing PTSD following trauma. A psychotherapeutic intervention initiated in the emergency department within hours of the trauma may mitigate this risk. The role of genetic predictors of risk and resilience should be further evaluated in larger, prospective intervention and prevention trials. ClinicalTrials.gov identifier: NCT00895518. © Copyright 2014 Physicians Postgraduate Press, Inc.

Effects of COMT inhibitors on striatal dopamine metabolism: A microdialysis study

NASA Technical Reports Server (NTRS)

Kaakkola, S.; Wurtman, R. J.

1992-01-01

In vivo microdialysis was used to examine the effect of two new catechol-O-methyltransferase (COMT) inhibitors, Ro 40-7592 and OR-611, on extracellular levels of dopamine, dihydroxyphenylacetic acid (DOPAC), homovanillic acid (HVA), and 5-hydroxyindoleacetic acid (5-HIAA) in rat striatum. The interactions of the COMT inhibitors with nomifensine, clorgyline, and deprenyl were also studied. Ro 40-7592 (3-30 mg/kg. i.p.) decreased dose-dependently the efflux of HVA, increased that of DOPAC, and tended to increase that of dopamine. Higher doses of OR-611 (30-100 mg/kg, i.p.) also decreased the dialysate level of HVA, increased that of DOPAC, and tended to increase that of dopamine. Ro 40-7592 was about ten-fold as potent as OR-611. Neither of the COMT inhibitors changed dialysate levels of 6-HIAA. An OR-611 dose of 10 mg/kg i.p. had no significant effect, in contrast to Ro 40-7592, on any of the parameters studied; this dose was thus used to differentiate between the effects of central and peripheral COMT inhibition. Both nomifensine (15 mg/kg, i.p.) and clorgyline (4 mg/kg, i.p.) alone elevated extracellular dopamine levels, and lowered those of DOPAC and HVA, though there were quantitative and temporal differences between the drugs. L-deprenyl (1 mg/kg, i.p.) alone had no significant effect on any of the compounds measured. Ro 40-7592 (10 mg/kg, i.p.) potentiated the effect of nomifensine on dopamine efflux, and it tended to increase clorgyline-induced dopamine efflux. DOPAC levels in dialysates were significantly increased by combinations of Ro 40-7592 and nomifensine or clorgyline, whereas HVA remained about as low as they were after Ro 40-7592 alone. Ro 40-7592 had no significant interactions with L-deprenyl. OR-611 (10 mg/kg, i.p.) did not modify the effects on dopamine metabolism of nomifensine, clorgyline, or L-deprenyl. These data show that Ro 40-7592 is a potent centrally active COMT inhibitor, whereas OR-611 is principally a peripherally active inhibitor. Use of drugs which inhibit brain COMT can considerably modify dopamine metabolism. COMT inhibitors may be of clinical significance in treating Parkinson's disease.

Associations of polymorphisms in the Pit-1 gene with growth and carcass traits in Angus beef cattle.

PubMed

Zhao, Q; Davis, M E; Hines, H C

2004-08-01

The Pit-1 gene was studied as a candidate for genetic markers of growth and carcass traits. Angus beef cattle that were divergently selected for high- or low-blood serum IGF-I concentration were used in this study. The single-strand conformation polymorphism method was used to identify polymorphism in the Pit-1 gene including regions from intron 2 to exon 6. Two polymorphisms, Pit1I3H (HinfI) and Pit1I3NL (NlaIII), were detected in intron 3 of the Pit-1 gene. One polymorphism, Pit1I4N (BstNI), was found in intron 4, and a single nucleotide polymorphism, Pit1I5, was found in intron 5. The previously reported polymorphism in exon 6, Pit1E6H (HinfI), was also studied in 416 Angus beef cattle. Associations of the polymorphisms with growth traits, carcass traits, and IGF-I concentration were analyzed using a general linear model procedure. No significant associations were observed between these polymorphisms and growth and carcass traits.

Identifying disease polymorphisms from case-control genetic association data.

PubMed

Park, L

2010-12-01

In case-control association studies, it is typical to observe several associated polymorphisms in a gene region. Often the most significantly associated polymorphism is considered to be the disease polymorphism; however, it is not clear whether it is the disease polymorphism or there is more than one disease polymorphism in the gene region. Currently, there is no method that can handle these problems based on the linkage disequilibrium (LD) relationship between polymorphisms. To distinguish real disease polymorphisms from markers in LD, a method that can detect disease polymorphisms in a gene region has been developed. Relying on the LD between polymorphisms in controls, the proposed method utilizes model-based likelihood ratio tests to find disease polymorphisms. This method shows reliable Type I and Type II error rates when sample sizes are large enough, and works better with re-sequenced data. Applying this method to fine mapping using re-sequencing or dense genotyping data would provide important information regarding the genetic architecture of complex traits.

Functional analysis of regulatory single-nucleotide polymorphisms.

PubMed

Pampín, Sandra; Rodríguez-Rey, José C

2007-04-01

The identification of regulatory polymorphisms has become a key problem in human genetics. In the past few years there has been a conceptual change in the way in which regulatory single-nucleotide polymorphisms are studied. We revise the new approaches and discuss how gene expression studies can contribute to a better knowledge of the genetics of common diseases. New techniques for the association of single-nucleotide polymorphisms with changes in gene expression have been recently developed. This, together with a more comprehensive use of the old in-vitro methods, has produced a great amount of genetic information. When added to current databases, it will help to design better tools for the detection of regulatory single-nucleotide polymorphisms. The identification of functional regulatory single-nucleotide polymorphisms cannot be done by the simple inspection of DNA sequence. In-vivo techniques, based on primer-extension, and the more recently developed 'haploChIP' allow the association of gene variants to changes in gene expression. Gene expression analysis by conventional in-vitro techniques is the only way to identify the functional consequences of regulatory single-nucleotide polymorphisms. The amount of information produced in the last few years will help to refine the tools for the future analysis of regulatory gene variants.

Association between ACE (rs4646994), FABP2 (rs1799883), MTHFR (rs1801133), FTO (rs9939609) Genes Polymorphism and Type 2 Diabetes with Dyslipidemia.

PubMed

Raza, Syed Tasleem; Abbas, Shania; Siddiqi, Zeba; Mahdi, Farzana

2017-01-01

Diabetic dyslipidemia is one of the leading causes of coronary artery disease (CAD) death. Genetic and environmental factors play an important role in the development of type 2 diabetes mellitus (T2DM) and dyslipidemia. The present study was aimed to investigate the association of ACE (rs4646994), FABP2 (rs1799883), MTHFR (rs1801133) and FTO (rs9939609) genes polymorphism in T2DM with dyslipidemia. Totally, 559 subjects including 221 T2DM cases with dyslipidemia, 158 T2DM without dyslipidemia and 180 controls were enrolled. ACE genes polymorphism was evaluated by polymerase chain reaction (PCR), while MTHFR , FABP2 , FTO genes polymorphisms were evaluated by PCR and restriction fragment length polymorphism (RFLP). Significant association of ACE and MTHFR genes polymorphisms were found in both group of cases [T2DM with dyslipidemia (P<0.001, and P=0.008, respectively) and T2DM without dyslipidemia (P=0.003, and P=0.010, respectively)] while FABP2 and FTO genes polymorphisms were significantly associated with T2DM without dyslipidemia (P=0.038, and P= 0.019, respectively). This study concludes that ACE , FABP2 , FTO and MTHFR genes are associated with T2DM. Additionally, it also seems that ACE and MTHFR genes might be further associated with the development of dyslipidemia in T2DM cases.

A meta-analysis evaluating the relationship between IL-18 gene promoter polymorphisms and an individual's susceptibility to HCV infection.

PubMed

Chen, W; Jing, M; Zhang, Q; Yuan, R; Jing, S

2018-01-01

Several observational studies have investigated interleukin-18 (IL-18) gene polymorphisms with regard to susceptibility to hepatitis C virus (HCV) infection, but the results have been inconsistent. To evaluate the relationships between functional polymorphisms in the IL-18 gene and an individual's susceptibility to HCV infection, a meta-analysis was performed. Methods: A literature search was conducted using the PubMed, EMBASE, Web of Science and China BioMedicine databases to investigate the correlation between IL-18 gene polymorphisms and susceptibility to HCV infection. Crude odds ratios (ORs) with 95% confidence intervals (CIs) were calculated. The polymorphisms IL-18-607 C>A and -137 G>C were correlated with susceptibility to HCV infection in Asian populations. However, there was no evidence indicating a correlation between either of these polymorphisms and susceptibility to HCV infection in Caucasian populations. Our current meta-analysis suggests that the -607 C>A and -137 G>C polymorphisms in the IL-18 gene promoter play important roles in determining the response to HCV in Asian populations. More studies with larger sample sizes are needed to evaluate the associations between IL-18 genetic polymorphisms and HCV infection risk. © Acta Gastro-Enterologica Belgica.

Association between alcoholism and the genetic polymorphisms of the GABAA receptor genes on chromosome 5q33-34 in Korean population.

PubMed

Park, Chul-Soo; Park, So-Young; Lee, Chul-Soon; Sohn, Jin-Wook; Hahn, Gyu-Hee; Kim, Bong-Jo

2006-06-01

Family, twin, and adoption studies have demonstrated that genes play an important role in the development of alcoholism. We investigated the association between alcoholism and the genetic polymorphisms of the GABAA receptor genes on chromosome 5q33-34 in Korean population. The genotype of the GABAA receptor gene polymorphisms were determined by performing polymerase chain reaction genotyping for 172 normal controls and 162 male alcoholics who are hospitalized in alcoholism treatment institute. We found a significant association between the genetic polymorphisms of the GABAA alpha1 and GABAA alpha6 receptor gene and alcoholism. The GG genotype of the GABAA alpha1 receptor gene was associated with the onset age of alcoholism and alcohol withdrawal symptoms, and a high score on the Korean version of the ADS. However, there was no association between the genetic polymorphisms of the GABAA beta2 and gamma2 receptor gene and alcoholisms. Our finding suggest that genetic polymorphisms of the GABAA alpha1 and GABAA alpha6 receptor gene may be associated with the development of alcoholism and that the GG genotype of the GABAA alpha1 receptor gene play an important role in the development of the early onset and the severe type of alcoholism.

Application of the Oriented-Eddy Collision Model to Complex Turbulent Flows

DTIC Science & Technology

2011-03-14

compare with data available from Matsumoto, Nagano, and Tsuji (1991) as well as L. Le Penven, J. N. Gence, and G. Comte -Bellot (1985). This provided a...0.15 0.2 0.25 0.3 0.35 0.4 0.45 0.5 time (s) Figure 20: Comparison to data from L. Le Penven, J. N. Gence, and G. Comte ...Bellot, case A. 0.005 0.05 0.1 0.2 0.25 0.3 0.15 time (s) Figure 21: Comparison to data from L. Le Penven, J. N. Gence, and G. Comte -Bellot, case B

Association of -604G/A and -501A/C Ghrelin and Obestatin Prepropeptide Gene Polymorphisms with Polycystic Ovary Syndrome.

PubMed

Ghaleh, Talaat Dabbaghi; Skandari, Somayeh Saadat; Najafipour, Reza; Rashvand, Zahra; Darabi, Masoud; Sahmani, Mehdi

2018-04-01

Ghrelin hormone has an important role in a wide range of metabolic and non-metabolic processes. Polymorphisms of ghrelin gene could be associated with a large number of diseases. The aim of this study was to evaluate the association of -604G/A and -501A/C polymorphisms in ghrelin and obestatin prepropeptide gene (GHRL) with polycystic ovary syndrome (PCOS) in a sample of Iranian women. One hundred and fifty-two women with PCOS and 162 age-matched apparently healthy women as control group were enrolled in this study. The study subjects were genotyped for polymorphisms in the ghrelin gene using polymerase chain reaction-restriction fragment length polymorphism-based methods. Biochemical parameters, serum prolactin, luteinizing hormone, follicle stimulating hormone, estradiol, and testosterone were estimated by chemiluminescence assay. Serum lipids and lipoproteins were determined by standard enzymatic methods. The association between the risk of PCOS and ghrelin gene polymorphisms was examined using Multivariate analysis. The frequency of the -604G/A and -501A/C polymorphisms was not statistically different between patients and the control group of women (p = 0.12 and p = 0.21, respectively). A significantly higher level of LDL-C was found in the wild-type AA genotype compared with CC genotype of -501A/C polymorphism (p = 0.02). Our findings indicate that neither -604G/A and nor -501A/C polymorphisms of ghrelin gene are associated with PCOS, but suggest a relation between the presence of polymorphic allele of -501A/C polymorphism and LDL-C level in a sample of Iranian women.

Gene analysis of steroid 5 alpha-reductase 1 in hyperandrogenic women.

PubMed

Eminović, Izet; Komel, Radovan; Prezelj, Janez; Karamehić, Jasenko; Gavrankapetanović, Faris; Heljić, Becir

2005-08-01

To examine the gene encoding for 5alpha-reductase type 1 in hyperandrogenic women, and assess the association of its eventual mutations or polymorphisms with the development of the hyperandrogenic female pattern. Sixteen hyperandrogenic women were included in the study. Single-stranded conformation polymorphism analysis (SSCP) and DNA sequencing were performed after polymerase chain reaction amplification of each of the 5 exons of the SRD5A1 gene in both hyperandrogenic and control group (16 participants). Sequence analysis identified the existence of many polymorphisms; in codon 24 of exon 1, GGC (Gly) into GAC (Asp); in codon 30 of exon 1, CGG (Arg) into CGC (Arg); in exon 3 codon 169, ACA to ACG (both encoding for threonine); in exon 5, AGA to AGG (both encoding for arginine, codon 260); and T/C polymorphism in intron 2. Polymorphisms were found in both groups. Polymorphisms of SRD5A1 gene were the same in both hyperandrogenic and healthy women, indicating no significant associations of genetic polymorphisms/variations of SRD5A1 gene with clinical manifestations of hyperandrogenic disorders in women.

Prevalence of combinatorial CYP2C9 and VKORC1 genotypes in Puerto Ricans: implications for warfarin management in Hispanics.

PubMed

Duconge, Jorge; Cadilla, Carmen L; Windemuth, Andreas; Kocherla, Mohan; Gorowski, Krystyna; Seip, Richard L; Bogaard, Kali; Renta, Jessica Y; Piovanetti, Paola; D'Agostino, Darrin; Santiago-Borrero, Pedro J; Ruaño, Gualberto

2009-01-01

Polymorphisms in the cytochrome P450 2C9 (CYP2C9) and vitamin K epoxide reductase complex subunit 1 (VKORC1) genes significantly alter the effective warfarin dose. We determined the frequencies of alleles, single carriers, and double carriers of single nucleotide polymorphisms (SNPs) in the CYP2C9 and VKORC1 genes in a Puerto Rican cohort and gauged the impact of these polymorphisms on warfarin dosage using a published algorithm. A total of 92 DNA samples were genotyped using Luminex x-MAP technology. The polymorphism frequencies were 6.52%, 5.43% and 28.8% for CYP2C9 *2, *3 and VKORC1-1639 C>A polymorphisms, respectively. The prevalence of combinatorial genotypes was 16% for carriers of both the CYP2C9 and VKORC1 polymorphisms, 9% for carriers of CYP2C9 polymorphisms, 35% for carriers of the VKORC1 polymorphism, and the remaining 40% were non-carriers for either gene. Based on a published warfarin dosing algorithm, single, double and triple carriers of functionally deficient polymorphisms predict reductions of 1.0-1.6, 2.0-2.9, and 2.9-3.7 mg/day, respectively, in warfarin dose. Overall, 60% of the population carried at least a single polymorphism predicting deficient warfarin metabolism or responsiveness and 13% were double carriers with polymorphisms in both genes studied. Combinatorial genotyping of CYP2C9 and VKORC1 can allow for individualized dosing of warfarin among patients with gene polymorphisms, potentially reducing the risk of stroke or bleeding.

Vitamin D receptor gene Alw I, Fok I, Apa I, and Taq I polymorphisms in patients with urinary stone.

PubMed

Seo, Ill Young; Kang, In-Hong; Chae, Soo-Cheon; Park, Seung Chol; Lee, Young-Jin; Yang, Yun Sik; Ryu, Soo Bang; Rim, Joung Sik

2010-04-01

To evaluate vitamin D receptor (VDR) gene polymorphisms in Korean patients so as to identify the candidate genes associated with urinary stones. Urinary stones are a multifactorial disease that includes various genetic factors. A normal control group of 535 healthy subjects and 278 patients with urinary stones was evaluated. Of 125 patients who presented stone samples, 102 had calcium stones on chemical analysis. The VDR gene Alw I, Fok I, Apa I, and Taq I polymorphisms were evaluated using the polymerase chain reaction-restriction fragment length polymorphism analysis. Allelic and genotypic frequencies were calculated to identify associations in both groups. The haplotype frequencies of the VDR gene polymorphisms for multiple loci were also determined. For the VDR gene Alw I, Fok I, Apa I, and Taq I polymorphisms, there was no statistically significant difference between the patients with urinary stones and the healthy controls. There was also no statistically significant difference between the patients with calcium stones and the healthy controls. A novel haplotype (Ht 4; CTTT) was identified in 13.5% of the patients with urinary stones and in 8.3% of the controls (P = .001). The haplotype frequencies were significantly different between the patients with calcium stones and the controls (P = .004). The VDR gene Alw I, Fok I, Apa I, and Taq I polymorphisms does not seem to be candidate genetic markers for urinary stones in Korean patients. However, 1 novel haplotype of the VDR gene polymorphisms for multiple loci might be a candidate genetic marker. Copyright 2010 Elsevier Inc. All rights reserved.

Association study of interleukin-4 polymorphisms with paranoid schizophrenia in the Polish population: a critical approach.

PubMed

Fila-Danilow, Anna; Kucia, Krzysztof; Kowalczyk, Malgorzata; Owczarek, Aleksander; Paul-Samojedny, Monika; Borkowska, Paulina; Suchanek, Renata; Kowalski, Jan

2012-08-01

Changes in immunological system are one of dysfunctions reported in schizophrenia. Some changes based on an imbalance between Th1 and Th2 cytokines results from cytokine gene polymorphisms. Interleukin-4 gene (IL4) is considered as a potential candidate gene in schizophrenia association studies. The aim of the current case-control study was to examine whether the -590C/T (rs2243250) and -33C/T (rs2070874) IL4 gene polymorphisms are implicated in paranoid schizophrenia development in the Polish population. Genotyping of polymorphisms was performed by using PCR-RFLP technique. The genotypes and alleles distribution of both SNPs were analysed in patients (n = 182) and healthy individuals constituted the control group (n = 215). The connection between some clinical variables and studied polymorphisms has been examined as well. We did not revealed any association between the -590C/T and -33C/T polymorphisms and paranoid schizophrenia. In case of both SNPs the homozygous TT genotype was extremely rare. Both polymorphic sites of the IL4 gene were found to be in a very strong linkage disequilibrium. However we did not identify a haplotype predispose to paranoid schizophrenia. No associations were also observed between the clinical course and psychopathology of the disease and the genotypes of both analysed polymorphisms. Our results suggest that the polymorphisms -590C/T in IL4 gene promoter region and -33C/T in the 5'-UTR are not involved in the pathophysiology of paranoid schizophrenia in Polish residents.

Polymorphisms in candidate genes for type 2 diabetes mellitus in a Mexican population with metabolic syndrome findings.

PubMed

Sánchez-Corona, J; Flores-Martínez, S E; Machorro-Lazo, M V; Galaviz-Hernández, C; Morán-Moguel, M C; Perea, F J; Mújica-López, K I; Vargas-Ancona, L; Laviada-Molina, H A; Fernández, V; Pardío, J; Arroyo, P; Barrera, H; Hanson, R L

2004-01-01

The metabolic or insulin resistance syndrome, characterized by hypertension, dyslipidemia, glucose intolerance and hyperinsulinemia, may have genetic determinants. The insulin gene (INS), insulin receptor gene (INSR) and insulin receptor substrate 1 gene (IRS1) have been proposed as candidate genes. We examined eight polymorphisms in these genes in 163 individuals from Yucatan, Mexico; this population has a high prevalence of obesity, type 2 diabetes mellitus and dyslipidemia. Subjects were evaluated for body mass index (BMI) and blood pressure. Blood samples were collected to determine glucose, insulin, triglycerides and cholesterol levels, as well as for DNA isolation. Restriction fragment length polymorphisms in INS, INSR and IRS1 were identified by polymerase chain reaction and digestion with selected restriction enzymes. Among the eight polymorphisms analyzed, the PstI polymorphism in INS was significantly associated with hypertriglyceridemia and with the presence of at least one abnormality related to the metabolic syndrome (P=0.007 and 0.004, respectively). The MaeIII polymorphism in INS was associated with fasting hyperinsulinemia (P=0.045). In multilocus analyses including both INS polymorphisms, significant associations were seen with hypertriglyceridemia (P=0.006), hypercholesterolemia (P=0.031) and with presence of at least one metabolic abnormality (P=0.009). None of the polymorphisms in INSR or IRS1 was associated with any of these traits. These findings suggest that the insulin gene may be an important determinant of metabolic syndrome, and particularly of dyslipidemia, in this population.

Interleukin-1 gene polymorphisms in chronic gastritis patients infected with Helicobacter pylori as risk factors of gastric cancer development.

PubMed

Hnatyszyn, Andrzej; Wielgus, Karolina; Kaczmarek-Rys, Marta; Skrzypczak-Zielinska, Marzena; Szalata, Marlena; Mikolajczyk-Stecyna, Joanna; Stanczyk, Jerzy; Dziuba, Ireneusz; Mikstacki, Adam; Slomski, Ryszard

2013-12-01

Epidemiological investigations indicated association of the Helicobacter pylori infections with the occurrence of inflammatory conditions of the gastric mucosa and development of chronic gastritis and intestinal type of gastric cancer. IL1A and IL1B genes have been proposed as key factors in determining risk of gastritis and malignant transformation. The aim of this paper was to evaluate association of interleukin-1 gene polymorphisms with chronic gastritis, atrophy, intestinal metaplasia, dysplasia and intestinal type of gastric cancer in H. pylori-infected patients. Patients subjected to analysis represent group of 144 consecutive cases that suffered from dyspepsia with coexisting infection of H. pylori and chronic gastritis, chronic atrophic gastritis, intestinal metaplasia, dysplasia or gastric cancer. Molecular studies involved analysis of -889C>T polymorphism of IL1A gene and +3954C>T polymorphism of IL1B gene. Statistical analysis of association of polymorphism -889C>T of gene IL1A with changes in gastric mucosa showed lack of significance, whereas +3954C>T polymorphism of IL1B gene showed significant association. Frequency of allele T of +3954C>T polymorphism of IL1B gene was higher in group of patients with chronic gastritis, atrophy, intestinal metaplasia, dysplasia or intestinal type of gastric cancer (32.1 %) as compared with population group (23 %), χ(2) = 4.61 and p = 0.03. This corresponds to odds ratio: 1.58, 95 % CI: 1.04-2.4. Our results indicate that +3954C>T polymorphism of IL1B gene increase susceptibility to inflammatory response of gastric mucosa H. pylori-infected patients and plays a significant role in the development of chronic gastritis, atrophy, intestinal metaplasia, dysplasia and the initiation of carcinogenesis.

Neurogentics of Dopaminergic Receptor Super-sensitivity in Activation of Brain Reward Circuitry and Relapse: Proposing “Deprivation-Amplification Relapse Therapy” (DART)

PubMed Central

Downs, B. William; Bowirrat, Abdalla; Waite, Roger L.; Braverman, Eric R.; Madigan, Margaret; Oscar-Berman, Marlene; DiNubile, Nicholas; Gold, Mark

2013-01-01

Background and Hypothesis It is well known that after prolonged abstinence, individuals who imbibe or use their drug of choice experience a powerful euphoria that precipitates serious relapse. While a biological explanation for this conundrum has remained elusive, we hypothesize that this clinically observed “super sensitivity” might be tied to genetic dopaminergic polymorphisms. Another therapeutic conundrum relates to the paradoxical finding that the dopaminergic agonist bromocriptine induces stronger activation of brain reward circuitry in individuals who carry the DRD2 A1 allele compared to DRD2 A2 allele carriers. Based upon the fact that carriers of the A1 allele relative to the A2 allele of the DRD2 gene have significantly lower D2 receptor density, a reduced sensitivity to dopamine agonist activity would be expected in the former. Thus, it is perplexing that with low D2 density there is an increase in reward sensitivity with the dopamine agonist bromocriptine. Moreover, under chronic or long-term therapy, the potential proliferation of D2 receptors with bromocriptine has been shown in vitro. This seems to lead to a positive outcome and significantly better treatment compliance only in A1 carriers. Proposal and Conclusion We propose that low D2 receptor density and polymorphisms of the D2 gene are associated with risk for relapse of substance abuse including alcohol dependence, heroin craving, cocaine dependence, methamphetamine abuse, nicotine sensitization, and glucose craving. With this in mind, we suggest a putative physiological mechanism that may help to explain the enhanced sensitivity following intense acute dopaminergic D2 receptor activation: “denervation supersensitivity.” Thus, the administration of dopamine D2 agonists would target D2 sensitization and attenuate relapse, especially in D2 receptor A1 allele carriers. This hypothesized mechanism is supported by clinical trials utilizing the amino-acid neurotransmitter precursors, enkephalinase and catechol-O-methyl-transferase (COMT) enzyme inhibition, which have resulted in attenuated relapse rates in Reward Deficiency Syndrome (RDS) probands. Future warranted translational research with positive outcome showing prevented or lower relapse in RDS will ultimately support the proposed concept, which we term “Deprivation-Amplification Relapse Therapy (DART).” PMID:19940429

Prenatal vitamins, one-carbon metabolism gene variants, and risk for autism

PubMed Central

Schmidt, Rebecca J.; Hansen, Robin L.; Hartiala, Jaana; Allayee, Hooman; Schmidt, Linda C.; Tancredi, Daniel J.; Tassone, Flora; Hertz-Picciotto, Irva

2011-01-01

Background Causes of autism are unknown. Associations with maternal nutritional factors and their interactions with gene variants have not been reported. Methods Northern California families were enrolled from 2003–2009 in the CHARGE (CHildhood Autism Risks from Genetics and Environment) population-based case-control study. Children aged 24–60 months were evaluated and confirmed to have autism (n = 288), autism spectrum disorder (n = 141), or typical development (n = 278) at the University of California–Davis Medical Investigation of Neurodevelopmental Disorders Institute using standardized clinical assessments. We calculated adjusted odds ratios (ORs) for associations between autism and retrospectively collected maternal vitamin intake before and during pregnancy. We explored interaction effects with functional genetic variants involved in one-carbon metabolism (MTHFR, COMT, MTRR, BHMT, FOLR2, CBS, and TCN2) as carried by the mother or child. Results Mothers of children with autism were less likely than those of typically developing children to report having taken prenatal vitamins during the three months before pregnancy or the first month of pregnancy (OR = 0.62 [95% confidence interval = 0.42–0.93]). Significant interaction effects were observed for maternal MTHFR 677 TT, CBS rs234715 GT+TT, and child COMT 472 AA genotypes, with greater risk for autism when mothers did not report taking prenatal vitamins periconceptionally (4.5 [1.4–14.6]; 2.6 [1.2–5.4]; and 7.2 [2.3–22.4], respectively). Greater risk was also observed for children whose mothers had other one-carbon metabolism pathway gene variants and reported no maternal prenatal vitamin intake. Conclusions Periconceptional use of prenatal vitamins may reduce the risk of having children with autism, especially for genetically susceptible mothers and children. Replication and mechanistic investigations are warranted. PMID:21610500

Positive effects of methylphenidate on hyperactivity are moderated by monoaminergic gene variants in children with autism spectrum disorders.

PubMed

McCracken, J T; Badashova, K K; Posey, D J; Aman, M G; Scahill, L; Tierney, E; Arnold, L E; Vitiello, B; Whelan, F; Chuang, S Z; Davies, M; Shah, B; McDougle, C J; Nurmi, E L

2014-06-01

Methylphenidate (MPH) reduces hyperactive-impulsive symptoms common in children with autism spectrum disorders (ASDs), however, response and tolerability varies widely. We hypothesized monoaminergic gene variants may moderate MPH effects in ASD, as in typically developing children with attention-deficit/hyperactivity disorder. Genotype data were available for 64 children with ASD and hyperactivity who were exposed to MPH during a 1-week safety/tolerability lead-in phase and 58 who went on to be randomized to placebo and three doses of MPH during a 4-week blinded, crossover study. Outcome measures included the Clinical Global Impression-Improvement (CGI-I) scale and the Aberrant Behavior Checklist (ABC-hyperactivity index). A total of 14 subjects discontinued the study because of MPH side effects. Subjects were genotyped for variants in DRD1-DRD5, ADRA2A, SLC6A3, SLC6A4, MAOA and MAOB, and COMT. Forty-nine percent of the sample met positive responder criteria. In this modest but relatively homogeneous sample, significant differences by DRD1 (P=0.006), ADRA2A (P<0.02), COMT (P<0.04), DRD3 (P<0.05), DRD4 (P<0.05), SLC6A3 (P<0.05) and SLC6A4 (P<0.05) genotypes were found for responders versus non-responders. Variants in DRD2 (P<0.001) and DRD3 (P<0.04) were associated with tolerability in the 14 subjects who discontinued the trial. For this first MPH pharmacogenetic study in children with ASD, multiple monoaminergic gene variants may help explain individual differences in MPH's efficacy and tolerability.

An Expert Review of Pharmacogenomics of Sickle Cell Disease Therapeutics: Not Yet Ready for Global Precision Medicine

PubMed Central

Mnika, Khuthala; Pule, Gift D.; Dandara, Collet

2016-01-01

Abstract Sickle cell disease (SCD) is a blood disease caused by a single nucleotide substitution (T > A) in the beta globin gene on chromosome 11. The single point mutation (Glu6Val) promotes polymerization of hemoglobin S (HbS) and causes sickling of erythrocytes. Vaso-occlusive painful crises are associated with recurrent and long-term use of analgesics/opioids and hydroxyurea (HU) by people living with SCD. The present analysis offers a state-of-the-art expert review of the effectiveness of pharmacogenomics/genetics of pain management in SCD, with specific focus on HU and opioids. The literature search used the following keywords: SCD, pharmacogenomics, pharmacogenetics, pain, antalgics, opioids, morphine, and HU. The literature was scanned until March 2016, with specific inclusion of targeted landmark and background articles on SCD. Surprisingly, our review identified only a limited number of studies that addressed the genetic/genomic basis of variable responses to pain (e.g., variants in OPRM1, HMOX-1, GCH1, VEGFA COMT genes), and pharmacogenomics of antalgics and opioids (e.g., variants in OPRM1, STAT6, ABCB1, and COMT genes) in SCD. There has been greater progress made toward identifying the key genomic variants, mainly in BCL11A, HBS1L-MYB, or SAR1, which contribute to response to HU treatment. However, the complete picture on pharmacogenomic determinants of the above therapeutic phenotypes remains elusive. Strikingly, no study has been conducted in sub-Saharan Africa where majority of the patients with SCD live. This alerts the broader global life sciences community toward the existing disparities in optimal and ethical targeting of research and innovation investments for SCD specifically and precision medicine and pharmacology research broadly. PMID:27636225

An Expert Review of Pharmacogenomics of Sickle Cell Disease Therapeutics: Not Yet Ready for Global Precision Medicine.

PubMed

Mnika, Khuthala; Pule, Gift D; Dandara, Collet; Wonkam, Ambroise

2016-10-01

Sickle cell disease (SCD) is a blood disease caused by a single nucleotide substitution (T > A) in the beta globin gene on chromosome 11. The single point mutation (Glu6Val) promotes polymerization of hemoglobin S (HbS) and causes sickling of erythrocytes. Vaso-occlusive painful crises are associated with recurrent and long-term use of analgesics/opioids and hydroxyurea (HU) by people living with SCD. The present analysis offers a state-of-the-art expert review of the effectiveness of pharmacogenomics/genetics of pain management in SCD, with specific focus on HU and opioids. The literature search used the following keywords: SCD, pharmacogenomics, pharmacogenetics, pain, antalgics, opioids, morphine, and HU. The literature was scanned until March 2016, with specific inclusion of targeted landmark and background articles on SCD. Surprisingly, our review identified only a limited number of studies that addressed the genetic/genomic basis of variable responses to pain (e.g., variants in OPRM1, HMOX-1, GCH1, VEGFA COMT genes), and pharmacogenomics of antalgics and opioids (e.g., variants in OPRM1, STAT6, ABCB1, and COMT genes) in SCD. There has been greater progress made toward identifying the key genomic variants, mainly in BCL11A, HBS1L-MYB, or SAR1, which contribute to response to HU treatment. However, the complete picture on pharmacogenomic determinants of the above therapeutic phenotypes remains elusive. Strikingly, no study has been conducted in sub-Saharan Africa where majority of the patients with SCD live. This alerts the broader global life sciences community toward the existing disparities in optimal and ethical targeting of research and innovation investments for SCD specifically and precision medicine and pharmacology research broadly.

Polymorphisms of the lipoprotein lipase gene as genetic markers for stroke in colombian population: a case control study.

PubMed

Velásquez Pereira, Leydi Carolina; Vargas Castellanos, Clara Inés; Silva Sieger, Federico Arturo

2016-12-30

To analyze if there is an association between the presence of polymorphisms in the LPL gene (rs320, rs285 and rs328) with development of acute ischemic stroke in Colombian population. In a case control design, 133 acute ischemic stroke patients (clinical diagnosis and x-ray CT) and 269 subjects without stroke as controls were studied. PCR -RFLP technique was used to detect rs320, rs285 and rs328 polymorphisms in the LPL gene. In the present research was not found any association between any of the LPL gene polymorphism and acute ischemic stroke in the population studied; the allele and genotypic frequencies of the studied polymorphisms were similar in cases and controls and followed the Hardy-Weinberg equilibrium. The study was approved by the IRB and each subject signed the informed consent. LPL gene polymorphisms are not genetic markers for the development of stroke in the Colombian sample used.

Melatonin mediated antidepressant-like effect in the hippocampus of chronic stress-induced depression rats: Regulating vesicular monoamine transporter 2 and monoamine oxidase A levels.

PubMed

Stefanovic, Bojana; Spasojevic, Natasa; Jovanovic, Predrag; Jasnic, Nebojsa; Djordjevic, Jelena; Dronjak, Sladjana

2016-10-01

The hippocampus is sensitive to stress which activates norepinephrine terminals deriving from the locus coeruleus. Melatonin exerts positive effects on the hippocampal neurogenic process and on depressive-like behaviour. Thus, in the present study, an examination was made of the effect of chronic melatonin treatment on norepinephrine content, synthesis, uptake, vesicular transport and degradation in the hippocampus of rats exposed to CUMS. This entailed quantifying the norephinephrine, mRNA and protein levels of DBH, NET, VMAT 2, MAO-A and COMT. The results show that CUMS evoked prolonged immobility. Melatonin treatment decreased immobility in comparison with the placebo group, reflecting an antidepressant-like effect. Compared with the placebo group, a dramatic decrease in norepinephrine content, decreased VMAT2 mRNA and protein and increased MAO-A protein levels in the hippocampus of the CUMS rats were observed. However, no significant differences in the levels of DBH, NET, COMT mRNA and protein and MAO-A mRNA levels between the placebo and the stressed groups were found. The results showed the restorative effects of melatonin on the stress-induced decline in the norepinephrine content of the hippocampus. It was observed that melatonin treatment in the CUMS rats prevented the stress-induced decrease in VMAT2 mRNA and protein levels, whereas it reduced the increase of the mRNA of COMT and protein levels of MAO-A. Chronic treatment with melatonin failed to alter the gene expression of DBH or NET in the hippocampus of the CUMS rats. Additionally, the results show that melatonin enhances VMAT2 expression and norepinephrine storage, whilst it reduces norepinephrine degrading enzymes. Copyright © 2016 Elsevier B.V. and ECNP. All rights reserved.

Proline and COMT Status Affect Visual Connectivity in Children with 22q11.2 Deletion Syndrome

PubMed Central

Magnée, Maurice J. C. M.; Lamme, Victor A. F.; de Sain-van der Velden, Monique G. M.; Vorstman, Jacob A. S.; Kemner, Chantal

2011-01-01

Background Individuals with the 22q11.2 deletion syndrome (22q11DS) are at increased risk for schizophrenia and Autism Spectrum Disorders (ASDs). Given the prevalence of visual processing deficits in these three disorders, a causal relationship between genes in the deleted region of chromosome 22 and visual processing is likely. Therefore, 22q11DS may represent a unique model to understand the neurobiology of visual processing deficits related with ASD and psychosis. Methodology We measured Event-Related Potentials (ERPs) during a texture segregation task in 58 children with 22q11DS and 100 age-matched controls. The C1 component was used to index afferent activity of visual cortex area V1; the texture negativity wave provided a measure for the integrity of recurrent connections in the visual cortical system. COMT genotype and plasma proline levels were assessed in 22q11DS individuals. Principal Findings Children with 22q11DS showed enhanced feedforward activity starting from 70 ms after visual presentation. ERP activity related to visual feedback activity was reduced in the 22q11DS group, which was seen as less texture negativity around 150 ms post presentation. Within the 22q11DS group we further demonstrated an association between high plasma proline levels and aberrant feedback/feedforward ratios, which was moderated by the COMT 158 genotype. Conclusions These findings confirm the presence of early visual processing deficits in 22q11DS. We discuss these in terms of dysfunctional synaptic plasticity in early visual processing areas, possibly associated with deviant dopaminergic and glutamatergic transmission. As such, our findings may serve as a promising biomarker related to the development of schizophrenia among 22q11DS individuals. PMID:21998713

Striatal dopamine release and impaired reinforcement learning in adults with 22q11.2 deletion syndrome.

PubMed

van Duin, Esther D A; Kasanova, Zuzana; Hernaus, Dennis; Ceccarini, Jenny; Heinzel, Alexander; Mottaghy, Felix; Mohammadkhani-Shali, Siamak; Winz, Oliver; Frank, Michael; Beck, Merrit C H; Booij, Jan; Myin-Germeys, Inez; van Amelsvoort, Thérèse

2018-06-01

22q11.2 deletion syndrome (22q11DS) is a genetic disorder caused by a microdeletion on chromosome 22q11.2 and associated with an increased risk for developing psychosis. The catechol-O-methyltransferase (COMT) gene is located in the deleted region and involved in dopamine (DA) breakdown. Impaired reinforcement learning (RL) is a recurrent feature in psychosis and thought to be related to abnormal striatal DA function. This study aims to examine RL and the potential association with striatal DA-ergic neuromodulation in 22q11DS. Twelve non-psychotic adults with 22q11DS and 16 healthy controls (HC) were included. A dopamine D 2/3 receptor [ 18 F]fallypride positron emission tomography (PET) scan was acquired while participants performed a modified version of the probabilistic stimulus selection task. RL-task performance was significantly worse in 22q11DS compared to HC. There were no group difference in striatal nondisplaceable binding potential (BP ND ) and task-induced DA release. In HC, striatal task-induced DA release was positively associated with task performance, but no such relation was found in 22q11DS subjects. Moreover, higher caudate nucleus task-induced DA release was found in COMT Met hemizygotes relative to Val hemizygotes. This study is the first to show impairments in RL in 22q11DS. It suggests that potentially motivational impairments are not only present in psychosis, but also in this genetic high risk group. These deficits may be underlain by abnormal striatal task-induced DA release, perhaps as a consequence of COMT haplo-insufficiency. Copyright © 2018 Elsevier B.V. and ECNP. All rights reserved.

Metabolism and gene polymorphisms of the folate pathway in Brazilian women with history of recurrent abortion.

PubMed

Boas, Wendell Vilas; Gonçalves, Rozana Oliveira; Costa, Olívia Lúcia Nunes; Goncalves, Marilda Souza

2015-02-01

To investigate the association between polymorphisms in genes that encode enzymes involved in folate- and vitamin B12-dependent homocysteine metabolism and recurrent spontaneous abortion (RSA). We investigated the C677T and A1298C polymorphisms of the methylenetetrahydrofalate reductase gene (MTHFR), the A2756G polymorphism of the methionine synthase gene (MS) and the 844ins68 insertion of the cystathionine beta synthetase gene (CBS). The PCR technique followed by RFLP was used to assess the polymorphisms; the serum levels of homocysteine, vitamin B12 and folate were investigated by chemiluminescence. The EPI Info Software version 6.04 was used for statistical analysis. Parametric variables were compared by Student's t-test and nonparametric variables by the Wilcoxon rank sum test. The frequencies of gene polymorphisms in 89 women with a history of idiopathic recurrent miscarriage and 150 controls were 19.1 and 19.6% for the C677T, insertion, 20.8 and 26% for the A1298C insertion, 14.2 and 21.9% for the A2756G insertion, and 16.4 and 18% for the 844ins68 insertion, respectively. There were no significant differences between case and control groups in any of the gene polymorphisms investigated. However, the frequency of the 844ins68 insertion in the CBS gene was higher among women with a history of loss during the third trimester of pregnancy (p=0.003). Serum homocysteine, vitamin B12 and folate levels id not differ between the polymorphisms studied in the case and control groups. However, linear regression analysis showed a dependence of serum folate levels on the maintenance of tHcy levels. The investigated gene polymorphisms and serum homocysteine, vitamin B12 and folate levels were not associated with idiopathic recurrent miscarriage in the present study. Further investigations are needed in order to confirm the role of the CBS 844ins68 insertion in recurrent miscarriage.

Coniferyl aldehyde 5-hydroxylation and methylation direct syringyl lignin biosynthesis in angiosperms

PubMed Central

Osakabe, Keishi; Tsao, Cheng Chung; Li, Laigeng; Popko, Jacqueline L.; Umezawa, Toshiaki; Carraway, Daniel T.; Smeltzer, Richard H.; Joshi, Chandrashekhar P.; Chiang, Vincent L.

1999-01-01

A central question in lignin biosynthesis is how guaiacyl intermediates are hydroxylated and methylated to the syringyl monolignol in angiosperms. To address this question, we cloned cDNAs encoding a cytochrome P450 monooxygenase (LsM88) and a caffeate O-methyltransferase (COMT) from sweetgum (Liquidambar styraciflua) xylem. Mass spectrometry-based functional analysis of LsM88 in yeast identified it as coniferyl aldehyde 5-hydroxylase (CAld5H). COMT expressed in Escherichia coli methylated 5-hydroxyconiferyl aldehyde to sinapyl aldehyde. Together, CAld5H and COMT converted coniferyl aldehyde to sinapyl aldehyde, suggesting a CAld5H/COMT-mediated pathway from guaiacyl to syringyl monolignol biosynthesis via coniferyl aldehyde that contrasts with the generally accepted route to sinapate via ferulate. Although the CAld5H/COMT enzyme system can mediate the biosynthesis of syringyl monolignol intermediates through either route, kcat/Km of CAld5H for coniferyl aldehyde was ≈140 times greater than that for ferulate. More significantly, when coniferyl aldehyde and ferulate were present together, coniferyl aldehyde was a noncompetitive inhibitor (Ki = 0.59 μM) of ferulate 5-hydroxylation, thereby eliminating the entire reaction sequence from ferulate to sinapate. In contrast, ferulate had no effect on coniferyl aldehyde 5-hydroxylation. 5-Hydroxylation also could not be detected for feruloyl-CoA or coniferyl alcohol. Therefore, in the presence of coniferyl aldehyde, ferulate 5-hydroxylation does not occur, and the syringyl monolignol can be synthesized only from coniferyl aldehyde. Endogenous coniferyl, 5-hydroxyconiferyl, and sinapyl aldehydes were detected, consistent with in vivo operation of the CAld5H/COMT pathway from coniferyl to sinapyl aldehydes via 5-hydroxyconiferyl aldehyde for syringyl monolignol biosynthesis. PMID:10430877

Pharmacological profile of opicapone, a third-generation nitrocatechol catechol-O-methyl transferase inhibitor, in the rat.

PubMed

Bonifácio, M J; Torrão, L; Loureiro, A I; Palma, P N; Wright, L C; Soares-da-Silva, P

2015-04-01

Catechol-O-methyltransferase (COMT) is an important target in the levodopa treatment of Parkinson's disease; however, the inhibitors available have problems, and not all patients benefit from their efficacy. Opicapone was developed to overcome those limitations. In this study, opicapone's pharmacological properties were evaluated as well as its potential cytotoxic effects. The pharmacodynamic effects of opicapone were explored by evaluating rat COMT activity and levodopa pharmacokinetics, in the periphery through microdialysis and in whole brain. The potential cytotoxicity risk of opicapone was explored in human hepatocytes by assessing cellular ATP content and mitochondrial membrane potential. Opicapone inhibited rat peripheral COMT with ED50 values below 1.4 mg⋅kg(-1) up to 6 h post-administration. The effect was sustained over the first 8 h and by 24 h COMT had not returned to control values. A single administration of opicapone resulted in increased and sustained plasma levodopa levels with a concomitant reduction in 3-O-methyldopa from 2 h up to 24 h post-administration, while tolcapone produced significant effects only at 2 h post-administration. The effects of opicapone on brain catecholamines after levodopa administration were sustained up to 24 h post-administration. Opicapone was also the least potent compound in decreasing both the mitochondrial membrane potential and the ATP content in human primary hepatocytes after a 24 h incubation period. Opicapone has a prolonged inhibitory effect on peripheral COMT, which extends the bioavailability of levodopa, without inducing toxicity. Thus, it exhibits some improved properties compared to the currently available COMT inhibitors. © 2014 The British Pharmacological Society.

Lack of association between deletion polymorphism of BIM gene and in vitro drug sensitivity in B-cell precursor acute lymphoblastic leukemia.

PubMed

Huang, Meixian; Miyake, Kunio; Kagami, Keiko; Abe, Masako; Shinohara, Tamao; Watanabe, Atsushi; Somazu, Shinpei; Oshiro, Hiroko; Goi, Kumiko; Goto, Hiroaki; Minegishi, Masayoshi; Iwamoto, Shotaro; Kiyokawa, Nobutaka; Sugita, Kanji; Inukai, Takeshi

2017-09-01

A deletion polymorphism in the BIM gene was identified as an intrinsic mechanism for resistance to tyrosine kinase inhibitor in chronic myeloid leukemia patients in East Asia. BIM is also involved in the responses to glucocorticoid and chemotherapy in acute lymphoblastic leukemia (ALL), suggesting a possible association between deletion polymorphism of BIM and the chemosensitivity of ALL. Thus, we analyzed 72 B-cell precursor (BCP)-ALL cell lines established from Japanese patients. Indeed, higher BIM gene expression was associated with good in vitro sensitivities to glucocorticoid and chemotherapeutic agents used in induction therapy. We also analyzed the methylation status of the BIM gene promoter by next generation sequencing of genome bisulfite PCR products, since genetic polymorphism could be insignificant when epigenetically inactivated. Hypermethylation of the BIM gene promoter was associated with lower BIM gene expression and poorer sensitivity to vincristine. Of note, however, the prevalence of a deletion polymorphism was not associated with the BIM gene expression level or drug sensitivities in BCP-ALL cell lines, in which the BIM gene was unmethylated. These observations suggest that an association of a deletion polymorphism of BIM and the response to induction therapy in BCP-ALL may be clinically minimal. Copyright © 2017. Published by Elsevier Ltd.

Inherited Variation in Cytokine, Acute Phase Response, and Calcium Metabolism Genes Affects Susceptibility to Infective Endocarditis

PubMed Central

Rutkovskaya, Natalia V.; Kondyukova, Natalia V.; Odarenko, Yuri N.; Kazachek, Yana V.; Tsepokina, Anna V.; Barbarash, Leonid S.

2017-01-01

Infective endocarditis (IE) is a septic inflammation of the endocardium. Recognition of microbial patterns, cytokine and acute phase responses, hemostasis features, and alterations in plasma lipid and calcium profile all have been reported to affect pathogenesis and clinical course of IE. Having recruited 123 patients with IE and 300 age-, sex-, and ethnicity-matched healthy blood donors, we profiled their genomic DNA for 35 functionally significant polymorphisms within the 22 selected genes involved in the abovementioned pathways, with the further genetic association analysis. We found that the G/A genotype of the rs1143634 polymorphism within the IL1B gene, the G/T genotype of the rs3212227 polymorphism within the IL12B gene, the A/G genotype of the rs1130864 polymorphism within the CRP gene, and the G allele of the rs1801197 polymorphism within the CALCR gene were associated with a decreased risk of IE whereas the T/T genotype of the rs1205 polymorphism within the CRP gene was associated with a higher risk of IE. Furthermore, heterozygous genotypes of the rs1143634 and rs3212227 polymorphisms were associated with the higher plasma levels of IL-1β and IL-12, respectively. Our results indicate that inherited variation in the cytokine, acute phase response, and calcium metabolism pathways may be linked to IE. PMID:28659664

Association of polymorphisms in nicotinic acetylcholine receptor alpha 4 subunit gene (CHRNA4), mu-opioid receptor gene (OPRM1), and ethanol-metabolizing enzyme genes with alcoholism in Korean patients.

PubMed

Kim, Soon Ae; Kim, Jong-Woo; Song, Ji-Young; Park, Sunny; Lee, Hee Jae; Chung, Joo-Ho

2004-01-01

Findings obtained from several studies indicate that ethanol enhances the activity of alpha4beta2 neuronal nicotinic acetylcholine receptor and support the possibility that a polymorphism of the nicotinic acetylcholine receptor alpha4 subunit gene (CHRNA4) modulates enhancement of nicotinic receptor function by ethanol. To identify the association between the CfoI polymorphism of the CHRNA4 and alcoholism, we examined distribution of genotypes and allele frequencies in Korean patients diagnosed with alcoholism (n = 127) and Korean control subjects without alcoholism (n = 185) with polymerase chain reaction-restriction fragment length polymorphism methods. We were able to detect the association between the CfoI polymorphism of the CHRNA4 and alcoholism in Korean patients (genotype P = .023; allele frequency P = .047). The genotypes and allele frequencies of known polymorphisms in other alcoholism candidate genes, such as alcohol metabolism-related genes [alcohol dehydrogenase 2 (ADH2), aldehyde dehydrogenase 2 (ALDH2), alcohol dehydrogenase 3 (ADH3), and cytochrome P450 2E1 (CYP2E1)] and mu-opioid receptor gene (OPRM1), were studied. The polymorphisms of ADH2, ALDH2, and CYP2E1 were significantly different in Korean patients with alcoholism and Korean control subjects without alcoholism, but ADH3 and OPRM1 did not differ between the two groups.

Association of ghrelin receptor gene polymorphism with bulimia nervosa in a Japanese population.

PubMed

Miyasaka, K; Hosoya, H; Sekime, A; Ohta, M; Amono, H; Matsushita, S; Suzuki, K; Higuchi, S; Funakoshi, A

2006-09-01

Eating disorders (EDs) have a highly heterogeneous etiology and multiple genetic factors might contribute to their pathogenesis. Ghrelin, a novel growth hormone-releasing peptide, enhances appetite and increases food intake, and human ghrelin plasma levels are inversely correlated with body mass index. In the present study, we examined the 171T/C polymorphism of the ghrelin receptor (growth hormone secretagogue receptor, GHSR) gene in patients diagnosed with EDs, because the subjects having ghrelin gene polymorphism (Leu72Met) was not detected in a Japanese population, previously. In addition, beta3 adrenergic receptor gene polymorphism (Try64Arg) and cholecystokinin (CCK)-A receptor (R) gene polymorphism (-81A/G, -128G/T), which are both associated with obesity, were investigated. The subjects consisted of 228 Japanese patients with EDs [96 anorexia nervosa (AN), 116 bulimia nervosa (BN) and 16 not otherwise specified (NOS)]. The age- and gender-matched control group consisted of 284 unrelated Japanese subjects. The frequency of the CC type of the GHSR gene was significantly higher in BN subjects than in control subjects (chi(2) = 4.47, p = 0.035, odds ratio = 2.05, Bonferroni correction: p = 0.070), while the frequency in AN subjects was not different from that in controls. The distribution of neither beta3 adrenergic receptor gene nor CCK-AR polymorphism differed between EDs and control subjects. Therefore, the CC type of GHSR gene polymorphism (171T/C) is a risk factor for BN, but not for AN.

Genetic association of cyclooxygenase-2 gene polymorphisms with Parkinson's disease susceptibility in Chinese Han population.

PubMed

Dai, Yi; Wu, Yuquan; Li, Yansheng

2015-01-01

The aim of this study was to explore the genetic association of cyclooxygenase-2 (COX2) gene promoter region polymorphisms with Parkinson's disease (PD) susceptibility in Chinese Han population. The genotyping of COX2 gene polymorphisms was conducted by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) in 122 patients with PD and 120 healthy persons. The association strength of gene polymorphism with disease was measured by odds ratio (OR) and 95% confidence interval (95% CI) calculated using χ(2) test which also evaluated the Hardy-Weinberg equilibrium (HWE) of gene polymorphism in controls. The linkage disequilibrium and haplotype were also analyzed as evidence in the analysis of association. On condition that the genotypes distributions of COX2 -1290A>G, -1195G>A, -765G>C in the control group all conformed to HWE, however, only the homozygous genotype AA of -1195G>A polymorphism showed an association with PD (OR=0.432, 95% CI=0.196-0.950). In addition, in haplotype analysis, G-A-C haplotype frequency in cases was significantly lower than the controls, compared with the common haplotype A-G-G (P=0.031, OR=0.375, 95% CI=0.149-0.940). COX2 -1195G>A polymorphism might play a protective role in the onset of PD and G-A-C haplotype in this three promoter region polymorphisms also showed a negative association.

Genetic polymorphism of antioxidant enzymes in eosinophilic and non-eosinophilic nasal polyposis.

PubMed

Akyigit, Abdulvahap; Keles, Erol; Etem, Ebru Onalan; Ozercan, Ibrahim; Akyol, Hatice; Sakallioglu, Oner; Karlidag, Turgut; Polat, Cahit; Kaygusuz, Irfan; Yalcin, Sinasi

2017-01-01

Chronic rhinosinusitis with nasal polyps (CRSwNP) is a chronic inflammatory disease of the paranasal sinuses, and its pathophysiology is not yet precisely known. It is suggested that oxygen free radicals play an important role in the pathogenesis of nasal polyposis. This study aimed to identify genetic polymorphisms of superoxide dismutase (SOD 2), catalase (CAT), and inducible nitric oxide synthase (iNOS) enzymes in eosinophilic CRSwNP and non-eosinophilic CRSwNP patients; the study also aimed to evaluate the effect of genetic polymorphism of antioxidant enzymes on CRSwNP etiopathogenesis. One hundred thirty patients, who received endoscopic sinus surgery due to CRSwNP, and 188 control individuals were included in this study. Nasal polyp tissues were divided into two groups histopathologically as eosinophilic CRSwNP and non-eosinophilic CRSwNP. Venous blood samples were taken from the patient and control groups. Polymorphisms in the Ala16Va1 gene, which is the most common variation of SOD-2 gene, and 21 A/T polymorphisms in catalase gene were evaluated with the restriction fragment length polymorphism method and -277 C/T polymorphism in the iNOS gene was evaluated with the DNA sequencing method. The GG genotype distribution for the (-277) A/G polymorphism in the iNOS gene was a statistically significant difference between eosinophilic CRSwNP and control groups (p < 0.05). The CC genotype distribution for the SOD2 A16V (C/T) polymorphism was not statistically significant in all groups (p > 0.05). The TT genotype distribution for the A/T polymorphism in catalase gene at position -21 was statistically significant differences in eosinophilic CRSwNP and control groups (p < 0.05). Increased free oxygen radical levels, which are considered effective factors in the pathogenesis of CRSwNP, can occur due to genetic polymorphism of enzymes in the antioxidant system and genetic polymorphism of antioxidant enzymes in eosinophilic CRSwNP patients might contribute to the pathophysiology.

Associations between the rs6010620 polymorphism in RTEL1 and risk of glioma: a meta-analysis of 20,711 participants.

PubMed

Wu, Yao; Tong, Xiang; Tang, Ling-Li; Zhou, Kai; Zhong, Chuan-Hong; Jiang, Shu

2014-01-01

Associations between the rs6010620 polymorphism in the regulator of telomere elongation helicase1 (RTEL1) gene and glioma have been widely reported but the results were not inconclusive. The aim of the current study was to investigate the association between the rs6010620 polymorphism in RTEL1 gene and risk of glioma by meta-analysis. We searched PubMed, Embase, Wanfang Weipu and CNKI (China National Knowledge Infrastructure) databases, which included all research published 05 May 2014. A total of 8,292 cases and 12,419 controls from 14 case-control studies involving the rs6010620 polymorphism in the RTEL1 gene were included. Statistical analysis was performed using STATA 12.0 software. The results indicated that the rs6010620 polymorphism in RTEL1 gene was indeed associated with risk of glioma (OR=1.474, 95%CI=1.282-1.694, p<0.001). On subgroup analysis by ethnicity, we found associations between the rs6010620 polymorphism in the RTEL1 gene and risk of glioma in both Caucasians and Asians. The current meta-analysis suggested that the rs6010620 polymorphism in the RTEL1 gene might increase risk of glioma. In future, larger case-control studies are needed to confirm our results.

Polymorphism at codon 36 of the p53 gene.

PubMed

Felix, C A; Brown, D L; Mitsudomi, T; Ikagaki, N; Wong, A; Wasserman, R; Womer, R B; Biegel, J A

1994-01-01

A polymorphism at codon 36 in exon 4 of the p53 gene was identified by single strand conformation polymorphism (SSCP) analysis and direct sequencing of genomic DNA PCR products. The polymorphic allele, present in the heterozygous state in genomic DNAs of four of 100 individuals (4%), changes the codon 36 CCG to CCA, eliminates a FinI restriction site and creates a BccI site. Including this polymorphism there are four known polymorphisms in the p53 coding sequence.

PREVALENCE OF COMBINATORIAL CYP2C9 AND VKORC1 GENOTYPES IN PUERTO RICANS: IMPLICATIONS FOR WARFARIN MANAGEMENT IN HISPANICS

PubMed Central

Duconge, Jorge; Cadilla, Carmen L.; Windemuth, Andreas; Kocherla, Mohan; Gorowski, Krystyna; Seip, Richard L.; Bogaard, Kali; Renta, Jessica Y.; Piovanetti, Paola; D’Agostino, Darrin; Santiago-Borrero, Pedro J.; Ruaño, Gualberto

2010-01-01

Polymorphisms in the cytochrome P450 2C9 (CYP2C9) and vitamin K epoxide reductase complex subunit 1 (VKORC1) genes significantly alter the effective warfarin dose. We determined the frequencies of alleles, single carriers, and double carriers of single nucleotide polymorphisms (SNPs) in the CYP2C9 and VKORC1 genes in a Puerto Rican cohort and gauged the impact of these polymorphisms on warfarin dosage using a published algorithm. A total of 92 DNA samples were genotyped using Luminex® x-MAP technology. The polymorphism frequencies were 6.52%, 5.43% and 28.8% for CYP2C9 *2, *3 and VKORC1-1639 G>A polymorphisms, respectively. The prevalence of combinatorial genotypes was 16% for carriers of both the CYP2C9 and VKORC1 polymorphisms, 9% for carriers of CYP2C9 polymorphisms, 35% for carriers of the VKORC1 polymorphism, and the remaining 40% were non-carriers for either gene. Based on a published warfarin dosing algorithm, single, double and triple carriers of functionally deficient polymorphisms predict reductions of 1.0–1.6, 2.0–2.9, and 2.9–3.7 mg/day, respectively, in warfarin dose. Overall, 60% of the population carried at least a single polymorphism predicting deficient warfarin metabolism or responsiveness and 13% were double carriers with polymorphisms in both genes studied. Combinatorial genotyping of CYP2C9 and VKORC1 can allow for individualized dosing of warfarin among patients with gene polymorphisms, potentially reducing the risk of stroke or bleeding. PMID:20073138

Frequency of CYP450 enzyme gene polymorphisms in the Greek population: review of the literature, original findings and clinical significance.

PubMed

Ragia, Georgia; Giannakopoulou, Efstathia; Karaglani, Makrina; Karantza, Ioanna-Maria; Tavridou, Anna; Manolopoulos, Vangelis G

2014-01-01

The cytochrome P450 (CYP450) enzyme family is involved in the oxidative metabolism of many therapeutic drugs and various endogenous substrates. These enzymes are highly polymorphic. Prevalence of CYP450 enzyme gene polymorphisms vary among different populations and substantial inter- and intra-ethnic variability in frequency of CYP450 enzyme gene polymorphisms has been reported. This paper provides an overview and investigation of CYP450 genotypic and phenotypic reports published in the Greek population.

Synthesis of [{sup 18}F]Ro41-0960, a potent COMT inhibitor, for use in vivo mapping with PET

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ding, Y.S.; Sugano, Y.; Gatley, S.J.

1995-05-01

Catechol-O-methyltransferase (COMPT; EC 2.1.1.6) is one of the two major enzymes which metabolize the catecholamine neurotransmitters. It is distributed throughout the body and brain and is elevated in breast cancer tissue when it plays a role in estrogen metabolism. It is also an important molecular target in the development of drugs to treat Parkinson`s disease (PD). Because COMT regulates the concentration of important neurotransmitter amines such as dopamine, there is speculation that abnormalities in its activity may be associated with neurological, and psychiatric disorders. Ro41-9060(3,4-dihydroxy-5-nitro-2{prime}-fluorobenzophenone) is a potent, fluorine containing COMT inhibitor which has been reported to cross the bloodmore » brain barrier. It is structurally similar to Ro40-7592 which is currently undergoing clinical trials in PD. We report the synthesis of [{sup 18}F]Ro41-0960, for investigation for mapping COMT and for studies of COMT drugs. [{sup 18}F]Ro41-0960 was synthesized by the nucleophilic aromatic substitution reaction with NCA [{sup 18}F] fluoride on a protected precursor (prepared via a five-step synthesis) followed by hydrolysis with HBr (synthesis time of 100 min; radiochemical yield of 5-7% (EOB)). Though Ro41-0960 has been reported to cross the blood brain barrier, PET studies in baboon demonstrated that an almost complete absence of the drug from the brain both at tracer doses and with the addition of unlabeled drug (1.5 mg/kg) at all times through a 90 min experimental interval. The plasma to brain ratios of F-18 average about 40:1. However, high uptake was observed in the kidneys and in other organs which are known to have high COMT. Studies in mice showed that at 30 min after injection of tracer, F-18 in kidneys was largely as [{sup 18}F]Ro-41-0960 and that it could be displaced with unlabeled Ro41-0960. These studies provide the first example of a positron emitter labeled COMT radiotracer.« less

Prolactin receptor gene polymorphism and the risk of recurrent pregnancy loss: a case-control study.

PubMed

Kim, Jin Ju; Choi, Young Min; Lee, Sung Ki; Yang, Kwang Moon; Paik, Eun Chan; Jeong, Hyeon Jeong; Jun, Jong Kwan; Han, Ae Ra; Hwang, Kyu Ri; Hong, Min A

2018-02-01

Since the first study was published reporting the candidate association between the prolactin receptor gene intron C/T polymorphism (rs37389) and recurrent miscarriage, no replication study has been performed. In this study, we investigated the role of the prolactin receptor gene C/T polymorphism in 311 Korean women with recurrent pregnancy loss and 314 controls. Genotyping for prolactin receptor gene intron C/T polymorphism was performed using a TaqMan assay. The significance of difference in the genotype distribution was assessed using a chi-square test, and continuous variables were compared using a Student's t-test. The genotype distribution of the prolactin receptor gene C/T polymorphism in the recurrent pregnancy loss group did not differ from that in the control group (CC/CT/TT rates were 49.8%/41.5%/8.7% and 52.5%/37.6%/9.9% for the recurrent pregnancy loss patient and control groups, respectively, p = .587). When the analysis was restricted to patients with three or more consecutive spontaneous miscarriages or patients without prior live birth, there were also no differences in the genotype distribution between these subgroups and controls. In conclusion, the findings of the current study suggest that the prolactin receptor gene intron C/T polymorphism is not a major determinant of the development of recurrent pregnancy loss. Impact statement What is already known: Many studies have investigated whether there is a genetic component for the risk of recurrent pregnancy loss. Recently, one study investigated whether genetic polymorphisms involved in the regulation of the hypothalamic-pituitary-ovarian axis would be associated with recurrent miscarriage. Among 35 polymorphisms in 20 candidate genes, genotype distribution with regard to the prolactin receptor gene intron C/T polymorphism (rs37389) differed between the recurrent miscarriage and the control groups. Since this study reporting the candidate association between the prolactin receptor gene and recurrent miscarriage, no replication study has been performed. What the results of this study add: The genotype distribution of the prolactin receptor gene C/T polymorphism in the recurrent miscarriage group did not differ from that in the control group. What the implications are of these findings: Our study may be useful in that it is the first replication study since the initial report of the association of prolactin receptor gene polymorphism with recurrent miscarriage. Although no association was found, the potential role of prolactin in pregnancy loss needs to be further investigated because prolactin and its receptor have been postulated to play an important role in the maintenance of normal pregnancy.

WDR1 and CLNK gene polymorphisms correlate with serum glucose and high-density lipoprotein levels in Tibetan gout patients.

PubMed

Lan, Bing; Chen, Peng; Jiri, Mutu; He, Na; Feng, Tian; Liu, Kai; Jin, Tianbo; Kang, Longli

2016-03-01

Current evidence suggests heredity and metabolic syndrome contributes to gout progression. Specifically, the WDR1 and CLNK genes may play a role in gout progression in European ancestry populations. However, no studies have focused on Chinese populations, especially Tibetan individuals. This study aims to determine whether variations in these two genes correlate with gout-related indices in Chinese-Tibetan gout patients. Eleven single-nucleotide polymorphisms in the WDR1 and CLNK genes were detected in 319 Chinese-Tibetan gout patients and 318 controls. We used one-way analysis of variance to evaluate the polymorphisms' effects on gout based on mean serum levels of metabolism indicators, such as albumin, glucose (GLU), triglycerides, cholesterol, high-density lipoproteins (HDL-C), creatinine, and uric acid, from fasting venous blood samples. All p values were Bonferroni corrected. Polymorphisms of the WDR1 and CLNK genes affected multiple risk factors for gout development. Significant differences in serum GLU levels were detected between different genotypic groups with WDRI polymorphisms rs4604059 (p = 0.005) and rs12498927 (p = 0.005). In addition, significant differences in serum HDL-C levels were detected between different genotypic groups with the CLNK polymorphism rs2041215 (p = 0.001). Polymorphisms of CLNK also affected levels of albumin, triglycerides, and creatinine. This study is the first to investigate and identify positive correlations between WDR1 and CLNK gene polymorphisms in Chinese-Tibetan populations. Our findings provide significant evidence for the effect of genetic polymorphisms on gout-related factors in Chinese-Tibetan populations.

Tumor Necrosis Factor-Alpha Gene Promoter Region Polymorphism and the Risk of Coronary Heart Disease

PubMed Central

Asifa, Gul Zareen; Kazmi, Syed Ali Raza; Javed, Qamar

2013-01-01

Background. Tumor necrosis factor-alpha (TNF-α) gene polymorphisms have been implicated in the manifestation of atherosclerosis. Controversy exists regarding the link between the cytokine's variant genotype and CHD among different ethnic groups. There have been fewer studies on the TNF-α gene −1031T>C and −863C>A polymorphisms in relation to CHD. Therefore, the current study was designed to investigate the association of the TNF-α gene −1031T>C and −863C>A polymorphisms with CHD in a Pakistani population. Methods. Patients with CHD (n = 310) and healthy individuals (n = 310) were enrolled in this study. Genotyping was performed by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP). Results. A significant difference was observed in the −863C>A polymorphism between patients with CHD and control subjects (P < 0.0001). CHD risk was positively associated with the variant allele −863A (P < 0.0001) in the study subjects. There was no significant link between the −1031T>C polymorphism and CHD risk in the study population. Haplotypes A-T and A-C of the TNF-alpha gene loci at −863 and −1031 showed higher frequency in the patient group compared with controls (P < 0.05). Conclusion. The TNF-α  −863C>A gene polymorphism was associated with the pathogenesis of CHD while the −1031T>C polymorphism did not show any link with the disease in a Pakistani population. PMID:24381514

Androgen Receptor Gene Polymorphism, Aggression, and Reproduction in Tanzanian Foragers and Pastoralists

PubMed Central

Butovskaya, Marina L.; Lazebny, Oleg E.; Vasilyev, Vasiliy A.; Dronova, Daria A.; Karelin, Dmitri V.; Mabulla, Audax Z. P.; Shibalev, Dmitri V.; Shackelford, Todd K.; Fink, Bernhard; Ryskov, Alexey P.

2015-01-01

The androgen receptor (AR) gene polymorphism in humans is linked to aggression and may also be linked to reproduction. Here we report associations between AR gene polymorphism and aggression and reproduction in two small-scale societies in northern Tanzania (Africa)—the Hadza (monogamous foragers) and the Datoga (polygynous pastoralists). We secured self-reports of aggression and assessed genetic polymorphism of the number of CAG repeats for the AR gene for 210 Hadza men and 229 Datoga men (aged 17–70 years). We conducted structural equation modeling to identify links between AR gene polymorphism, aggression, and number of children born, and included age and ethnicity as covariates. Fewer AR CAG repeats predicted greater aggression, and Datoga men reported more aggression than did Hadza men. In addition, aggression mediated the identified negative relationship between CAG repeats and number of children born. PMID:26291982

Matrix-Gla Protein rs4236 [A/G] gene polymorphism and serum and GCF levels of MGP in patients with subgingival dental calculus.

PubMed

Doğan, Gülnihal Emrem; Demir, Turgut; Aksoy, Hülya; Sağlam, Ebru; Laloğlu, Esra; Yildirim, Abdulkadir

2016-10-01

Matrix-Gla Protein (MGP) is one of the major Gla-containing protein associated with calcification process. It also has a high affinity for Ca 2+ and hydroxyapatite. In this study we aimed to evaluate the MGP rs4236 [A/G] gene polymorphism in association with subgingival dental calculus. Also a possible relationship between MGP gene polymorphism and serum and GCF levels of MGP were examined. MGP rs4236 [A/G] gene polymorphism was investigated in 110 patients with or without subgingival dental calculus, using polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) techniques. Additionally, serum and GCF levels of MGP of the patients were compared according to subgingival dental calculus. Comparison of patients with and without subgingival dental calculus showed no statistically significant difference in MGP rs4236 [A/G] gene polymorphism (p=0.368). MGP concentrations in GCF of patients with subgingival dental calculus were statistically higher than those without subgingival dental calculus (p=0.032). However, a significant association was not observed between the genotypes of AA, AG and GG of the MGP rs4236 gene and the serum and GCF concentrations of MGP in subjects. In this study, it was found that MGP rs4236 [A/G] gene polymorphism was not to be associated with subgingival dental calculus. Also, that GCF MGP levels were detected higher in patients with subgingival dental calculus than those without subgingival dental calculus independently of polymorphism, may be the effect of adaptive mechanism to inhibit calculus formation. Copyright © 2016 Elsevier Ltd. All rights reserved.

Cytokine gene polymorphisms in bullous pemphigoid in a Chinese population.

PubMed

Chang, Y T; Liu, H N; Yu, C W; Lin, M W; Huang, C H; Chen, C C; Liu, M T; Lee, D D; Wang, W J; Tsai, S F

2006-01-01

Bullous pemphigoid (BP) is an autoimmune bullous disease mostly associated with autoantibodies to the hemidesmosomal BP autoantigens BP180 and BP230. High levels of interleukin (IL)-1beta, IL-4, IL-5, IL-6, IL-8, IL-10, IL-13, tumour necrosis factor (TNF)-alpha and interferon (IFN)-gamma have been detected in skin lesions or sera of patients with BP. Cytokine gene polymorphisms may affect cytokine production and contribute to susceptibility to autoimmune diseases. Until now, no cytokine gene polymorphism study has been conducted on patients with BP. We aimed to determine whether the genetic polymorphisms of the cytokine genes might influence the development of BP. DNA samples were obtained from 96 BP patients and 174 control subjects. Using direct sequencing and microsatellite genotyping, we examined 23 polymorphisms in 11 cytokine genes including the IL-1alpha, IL-1beta, IL-1 receptor antagonist, IL-4, IL-6, IL-8, IL-10, IL-13, IL-4 receptor, TNF-alpha and IFN-gamma genes. Although the BP patients were more likely to carry the -511T and -31C alleles of the IL-1beta gene (P = 0.04), the significance disappeared after correction for multiple testing (Pc). There was complete linkage disequilibrium between the -511T and -31C alleles of the IL-1beta gene. In female patients with BP, the associations with IL-1beta (-511T) and (-31C) alleles were much stronger (68% vs. 40.6%, odds ratio = 3.11, Pc = 0.006). No significantly different allelic and genotypic distributions of other cytokine gene polymorphisms could be found between the patients with BP and controls. Moreover, no association with the extent of disease involvement (localized or generalized) was observed. The IL-1beta (-511) and (-31) polymorphisms were significantly associated with BP in women. The other genetic polymorphisms of cytokine genes that we analysed do not appear to be associated with BP susceptibility in our Chinese population.

Association between estrogen receptora gene (ESR1) PvuII (T/C) and XbaI (A/G) polymorphisms and premature ovarian failure risk: evidence from a meta-analysis.

PubMed

He, Meirong; Shu, Jingcheng; Huang, Xing; Tang, Hui

2015-02-01

Genetic factors are important in the pathogenesis of Premature ovarian failure (POF). Notably, estrogen receptor-a (ESR1) has been suggested as a possible candidate gene for POF; however, published studies of ESR1 gene polymorphisms have been hampered by small sample sizes and inconclusive or ambiguous results. The aim of this meta analysis is to investigate the associations between two novel common ESR1 polymorphisms (intron 1 polymorphisms PvuII-rs2234693: T.C and XbaI-rs9340799: A.G) and POF. A comprehensive search was conducted to identify all studies on the association of ESR1 gene polymorphisms with POF up to August 2014. Pooled odds ratio (OR) and corresponding 95 % confidence interval (CI) were calculated using fixed-or random-effects model in the meta-analysis. Three studies covering 1396 subjects were identified. Pooled data showed significant association between ESR1 gene PvuII polymorphism and risk of POF: [allele model: Cvs. T, OR = 0.735, 95%CI: 0.624 ~ 0.865, p = 0.001; co-dominant models: CCvs.TT, OR = 0.540, 95%CI: 0.382 ~ 0.764, p = 0.001, CTvs.TT, OR = 0.735, 95%CI: 0.555 ~ 0.972, p = 0.031; dominant model: CT + CCvs.TT, OR = 0.618, 95%CI: 0.396 ~ 0.966, p = 0.035; recessive model: CCvs.TT + CT, OR = 0.659, 95%CI: 0.502 ~ 0.864, p = 0.003]. Subgroup analyses showed a significant association in all models in Asian population, but no significant association in any model in European population. For the XbaI polymorphism, overall, no significant association was observed under any genetic models. However, under dominant model, ESR1 gene XbaI polymorphism is significantly association with risk of POF in Asian population. The present meta-analysis suggests that ESR1gene PvuII polymorphism is significantly associated with an increased risk of POF. And ESR1gene XbaI polymorphism is not association with risk of POF overall. However, under dominant model, ESR1gene XbaI polymorphism is significantly association with risk of POF in Asian population. Further large and well-designed studies are needed to confirm the association.

[Five Franche-Comté doctors and surgeons during the Revolution, Empire and the Restoration].

PubMed

Antoine, Henri-Michel; Magnin, Pierre; Maurat, Jean-Pierre

2007-01-01

Five doctors played an important part in medicine in Franche-Comté and more generally speaking in France, during the French Revolution, Empire and Restauration: J.F. Desault, E. Tourtelle, P.F. Percy, J.F. Thomassin and P.F. Briot.

The impact of the catechol-O-methyltransferase genotype on vascular function and blood pressure after acute green tea ingestion.

PubMed

Miller, Rosalind J; Jackson, Kim G; Dadd, Tony; Mayes, Andrew E; Brown, A Louise; Lovegrove, Julie A; Minihane, Anne M

2012-06-01

Evidence for the benefits of green tea catechins on vascular function is inconsistent, with genotype potentially contributing to the heterogeneity in response. Here, the impact of the catechol-O-methyltransferase (COMT) genotype on vascular function and blood pressure (BP) after green tea extract ingestion are reported. Fifty subjects (n = 25 of the proposed low-activity [AA] and of the high-activity [GG] COMT rs4680 genotype), completed a randomized, double-blind, crossover study. Peripheral arterial tonometry, digital volume pulse (DVP), and BP were assessed at baseline and 90 min after 1.06 g of green tea extract or placebo. A 5.5 h and subsequent 18.5 h urine collection was performed to assess green tea catechin excretion. A genotype × treatment interaction was observed for DVP reflection index (p = 0.014), with green tea extract in the AA COMT group attenuating the increase observed with placebo. A tendency for a greater increase in diastolic BP was evident at 90 min after the green tea extract compared to placebo (p = 0.07). A genotypic effect was observed for urinary methylated epigallocatechin during the first 5.5 h, with the GG COMT group demonstrating a greater concentration (p = 0.049). Differences in small vessel tone according to COMT genotype were evident after acute green tea extract. © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

SbCOMT (Bmr12) is involved in the biosynthesis of tricin-lignin in sorghum

DOE Office of Scientific and Technical Information (OSTI.GOV)

Eudes, Aymerick; Dutta, Tanmoy; Deng, Kai

Lignin in plant biomass represents a target for engineering strategies towards the development of a sustainable bioeconomy. In addition to the conventional lignin monomers, namely p-coumaryl, coniferyl and sinapyl alcohols, tricin has been shown to be part of the native lignin polymer in certain monocot species. Because tricin is considered to initiate the polymerization of lignin chains, elucidating its biosynthesis and mechanism of export to the cell wall constitute novel challenges for the engineering of bioenergy crops. Late steps of tricin biosynthesis require two methylation reactions involving the pathway intermediate selgin. It has recently been demonstrated in rice and maizemore » that caffeate O-methyltransferase (COMT) involved in the synthesis syringyl (S) lignin units derived from sinapyl alcohol also participates in the synthesis of tricin in planta. In this work, we validate in sorghum (Sorghum bicolor L.) that the O-methyltransferase responsible for the production of S lignin units (SbCOMT / Bmr12) is also involved in the synthesis of lignin-linked tricin. In particular, we show that biomass from the sorghum bmr12 mutant contains lower level of tricin incorporated into lignin, and that SbCOMT can methylate the tricin precursors luteolin and selgin. Our genetic and biochemical data point toward a general mechanism whereby COMT is involved in the synthesis of both tricin and S lignin units.« less

SbCOMT (Bmr12) is involved in the biosynthesis of tricin-lignin in sorghum

PubMed Central

Eudes, Aymerick; Dutta, Tanmoy; Deng, Kai; Jacquet, Nicolas; Sinha, Anagh; Benites, Veronica T.; Baidoo, Edward E. K.; Richel, Aurore; Sattler, Scott E.; Northen, Trent R.; Singh, Seema; Simmons, Blake A.

2017-01-01

Lignin in plant biomass represents a target for engineering strategies towards the development of a sustainable bioeconomy. In addition to the conventional lignin monomers, namely p-coumaryl, coniferyl and sinapyl alcohols, tricin has been shown to be part of the native lignin polymer in certain monocot species. Because tricin is considered to initiate the polymerization of lignin chains, elucidating its biosynthesis and mechanism of export to the cell wall constitute novel challenges for the engineering of bioenergy crops. Late steps of tricin biosynthesis require two methylation reactions involving the pathway intermediate selgin. It has recently been demonstrated in rice and maize that caffeate O-methyltransferase (COMT) involved in the synthesis syringyl (S) lignin units derived from sinapyl alcohol also participates in the synthesis of tricin in planta. In this work, we validate in sorghum (Sorghum bicolor L.) that the O-methyltransferase responsible for the production of S lignin units (SbCOMT / Bmr12) is also involved in the synthesis of lignin-linked tricin. In particular, we show that biomass from the sorghum bmr12 mutant contains lower level of tricin incorporated into lignin, and that SbCOMT can methylate the tricin precursors luteolin and selgin. Our genetic and biochemical data point toward a general mechanism whereby COMT is involved in the synthesis of both tricin and S lignin units. PMID:28594846

Catechol-O-methyltransferase Val(158)Met association with parahippocampal physiology during memory encoding in schizophrenia.

PubMed

Di Giorgio, A; Caforio, G; Blasi, G; Taurisano, P; Fazio, L; Romano, R; Ursini, G; Gelao, B; Bianco, L Lo; Papazacharias, A; Sinibaldi, L; Popolizio, T; Bellomo, A; Bertolino, A

2011-08-01

Catechol-O-methyltransferase (COMT) Val158Met has been associated with activity of the mesial temporal lobe during episodic memory and it may weakly increase risk for schizophrenia. However, how this variant affects parahippocampal and hippocampal physiology when dopamine transmission is perturbed is unclear. The aim of the present study was to compare the effects of the COMT Val158Met genotype on parahippocampal and hippocampal physiology during encoding of recognition memory in patients with schizophrenia and in healthy subjects. Using blood oxygen level-dependent (BOLD) functional magnetic resonance imaging (fMRI), we studied 28 patients with schizophrenia and 33 healthy subjects matched for a series of sociodemographic and genetic variables while they performed a recognition memory task. We found that healthy subjects had greater parahippocampal and hippocampal activity during memory encoding compared to patients with schizophrenia. We also found different activity of the parahippocampal region between healthy subjects and patients with schizophrenia as a function of the COMT genotype, in that the predicted COMT Met allele dose effect had an opposite direction in controls and patients. Our results demonstrate a COMT Val158Met genotype by diagnosis interaction in parahippocampal activity during memory encoding and may suggest that modulation of dopamine signaling interacts with other disease-related processes in determining the phenotype of parahippocampal physiology in schizophrenia. © Cambridge University Press 2010

SbCOMT (Bmr12) is involved in the biosynthesis of tricin-lignin in sorghum

DOE PAGES

Eudes, Aymerick; Dutta, Tanmoy; Deng, Kai; ...

2017-06-08

Lignin in plant biomass represents a target for engineering strategies towards the development of a sustainable bioeconomy. In addition to the conventional lignin monomers, namely p-coumaryl, coniferyl and sinapyl alcohols, tricin has been shown to be part of the native lignin polymer in certain monocot species. Because tricin is considered to initiate the polymerization of lignin chains, elucidating its biosynthesis and mechanism of export to the cell wall constitute novel challenges for the engineering of bioenergy crops. Late steps of tricin biosynthesis require two methylation reactions involving the pathway intermediate selgin. It has recently been demonstrated in rice and maizemore » that caffeate O-methyltransferase (COMT) involved in the synthesis syringyl (S) lignin units derived from sinapyl alcohol also participates in the synthesis of tricin in planta. In this work, we validate in sorghum (Sorghum bicolor L.) that the O-methyltransferase responsible for the production of S lignin units (SbCOMT / Bmr12) is also involved in the synthesis of lignin-linked tricin. In particular, we show that biomass from the sorghum bmr12 mutant contains lower level of tricin incorporated into lignin, and that SbCOMT can methylate the tricin precursors luteolin and selgin. Our genetic and biochemical data point toward a general mechanism whereby COMT is involved in the synthesis of both tricin and S lignin units.« less