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1

Genetic background affects susceptibility to tumoral stem cell reprogramming  

PubMed Central

The latest studies of the interactions between oncogenes and its target cell have shown that certain oncogenes may act as passengers to reprogram tissue-specific stem/progenitor cell into a malignant cancer stem cell state. In this study, we show that the genetic background influences this tumoral stem cell reprogramming capacity of the oncogenes using as a model the Sca1-BCRABLp210 mice, where the type of tumor they develop, chronic myeloid leukemia (CML), is a function of tumoral stem cell reprogramming. Sca1-BCRABLp210 mice containing FVB genetic components were significantly more resistant to CML. However, pure Sca1-BCRABLp210 FVB mice developed thymomas that were not seen in the Sca1-BCRABLp210 mice into the B6 background. Collectively, our results demonstrate for the first time that tumoral stem cell reprogramming fate is subject to polymorphic genetic control.

Garcia-Ramirez, Idoia; Ruiz-Roca, Lucia; Martin-Lorenzo, Alberto; Blanco, Oscar; Garcia-Cenador, Maria Begona; Garcia-Criado, Francisco Javier; Vicente-Duenas, Carolina; Sanchez-Garcia, Isidro

2013-01-01

2

Genetic background affects susceptibility to mammary hyperplasias and carcinomas in Apc(min)/+ mice.  

PubMed

Treatment of female C57BL/6J (B6) mice carrying the mutant Min allele of the adenomatous polyposis coli (Apc) gene with ethylnitrosourea (ENU) results in approximately 90% of mice developing an average of three mammary tumors within 65 days. As a first step in the identification of loci modifying susceptibility to ENU-induced mammary tumors and hyperplasias, we have tested ENU-treated Apc(Min)/+ (Min/+) mice on several hybrid backgrounds for susceptibility to mammary and intestinal tumors. C57BR/cdJxB6 (BRB6) Min/+ mice were more sensitive to development of mammary squamous cell carcinomas than B6 Min/+ mice. In contrast, Min/+ hybrids between B6 and FVB/NTac (FVB), 129X1/SvJ (129X1), and 129S6/SvEvTac (129S6) were all significantly more resistant to mammary carcinoma development. However, mice from these three crosses developed more focal mammary hyperplasias than did the B6 or BRB6 Min/+ mice. Susceptibility to intestinal tumors was independent of mammary tumor susceptibility in most hybrids. These results indicate that genetic background can affect independently the phenotypes conferred by the Min allele of APC: PMID:11309311

Moser, A R; Hegge, L F; Cardiff, R D

2001-04-15

3

Mitochondrial genetic background modulates bioenergetics and susceptibility to acute cardiac volume overload.  

PubMed

Dysfunctional bioenergetics has emerged as a key feature in many chronic pathologies such as diabetes and cardiovascular disease. This has led to the mitochondrial paradigm in which it has been proposed that mtDNA sequence variation contributes to disease susceptibility. In the present study we show a novel animal model of mtDNA polymorphisms, the MNX (mitochondrial-nuclear exchange) mouse, in which the mtDNA from the C3H/HeN mouse has been inserted on to the C57/BL6 nuclear background and vice versa to test this concept. Our data show a major contribution of the C57/BL6 mtDNA to the susceptibility to the pathological stress of cardiac volume overload which is independent of the nuclear background. Mitochondria harbouring the C57/BL6J mtDNA generate more ROS (reactive oxygen species) and have a higher mitochondrial membrane potential relative to those with C3H/HeN mtDNA, independent of nuclear background. We propose this is the primary mechanism associated with increased bioenergetic dysfunction in response to volume overload. In summary, these studies support the 'mitochondrial paradigm' for the development of disease susceptibility, and show that the mtDNA modulates cellular bioenergetics, mitochondrial ROS generation and susceptibility to cardiac stress. PMID:23924350

Fetterman, Jessica L; Zelickson, Blake R; Johnson, Larry W; Moellering, Douglas R; Westbrook, David G; Pompilius, Melissa; Sammy, Melissa J; Johnson, Michelle; Dunham-Snary, Kimberly J; Cao, Xuemei; Bradley, Wayne E; Zhang, Jinju; Wei, Chih-Chang; Chacko, Balu; Schurr, Theodore G; Kesterson, Robert A; Dell'italia, Louis J; Darley-Usmar, Victor M; Welch, Danny R; Ballinger, Scott W

2013-10-15

4

Loss of STAT6 promotes autoimmune disease and atopy on a susceptible genetic background.  

PubMed

Atopy and autoimmunity are usually considered opposed immunological manifestations. Lyn(-/-) mice develop lupus-like autoimmune disease yet have coexistent intrinsic allergic traits and are prone to severe, persistent asthma induced exogenously. Recently it has been proposed that the Th2 environment and IgE auto-Abs promotes autoimmune disease in Lyn(-/-) mice. To examine this apparent contradiction, we derived Lyn(-/-) mice with a null mutation in STAT6, a regulator of Th2 immunity that integrates signaling from the IL-4/IL-13 receptor complex. Atopy and spontaneous peritoneal eosinophilia, characteristic of Lyn(-/-) mice, were lost in young Lyn(-/-)STAT6(-/-) mice; however, autoimmune disease was markedly exacerbated. At a time-point where Lyn(-/-) mice showed only mild autoimmune disease, Lyn(-/-)STAT6(-/-) mice had maximal titres of IgG and IgA auto-Abs, impaired renal function, myeloid expansion and a highly activated T cell compartment. Remarkably, low level IgE auto-Abs but not IgG1 auto-Abs were a feature of some aged Lyn(-/-)STAT6(-/-) mice. Furthermore, aged Lyn(-/-)STAT6(-/-) mice showed dramatically increased levels of serum IgE but minimal IgG1, suggesting that class-switching to IgE can occur in the absence of an IgG1 intermediate. The results show that Lyn-deficient mice can overcome the effects of disabling Th2 immunity, highlighting the importance of Lyn in controlling Th2 responses. Our data also indicates that, under certain conditions, STAT6-independent factors can promote IgE class-switching. This work has important clinical implications as many experimental therapies designed for the treatment of asthma or atopy are based on targeting the STAT6 axis, which could potentially reveal life endangering autoimmunity or promote atopy in susceptible individuals. PMID:22867713

Lau, Maverick; Tsantikos, Evelyn; Maxwell, Mhairi J; Tarlinton, David M; Anderson, Gary P; Hibbs, Margaret L

2012-12-01

5

Methicillin-susceptible Staphylococcus aureus CC398: First description in prosthetic joint infection and genetic background comparison with nasal carriage isolates.  

PubMed

Few reports described infections with CC398 methicillin-susceptible Staphylococcus aureus (MSSA). We compared the genetic background of CC398 MSSA strains from nasal carriage and knee arthroplasty infection. DNA microarray analysis shows acquisition of particular adhesin, iron capture system and immune defense evasion mechanisms. These characteristics could explain pathogenesis in this type of infection. PMID:24767465

Aubin, Guillaume G; Lepelletier, Didier; Reynaud, Alain; Lavigne, Jean-Philippe; Corvec, Stéphane

2014-06-01

6

Genetic Susceptibility to Cancer  

Cancer.gov

The Epidemiology and Genomics Research Program (EGRP) is a strong supporter of epidemiology studies investigating genetic susceptibility to cancer across all populations, including family studies, candidate gene studies, genome-wide association studies (GWAS), and use of next generation sequencing techniques to identify variants associated with specific cancers. Such studies have identified many genetic variants that may be associated with cancer.

7

Genetic Susceptibility to Atherosclerosis  

PubMed Central

Atherosclerosis is a complex multifocal arterial disease involving interactions of multiple genetic and environmental factors. Advances in techniques of molecular genetics have revealed that genetic ground significantly influences susceptibility to atherosclerotic vascular diseases. Besides further investigations of monogenetic diseases, candidate genes, genetic polymorphisms, and susceptibility loci associated with atherosclerotic diseases have been identified in recent years, and their number is rapidly increasing. This paper discusses main genetic investigations fields associated with human atherosclerotic vascular diseases. The paper concludes with a discussion of the directions and implications of future genetic research in arteriosclerosis with an emphasis on prospective prediction from an early age of individuals who are predisposed to develop premature atherosclerosis as well as to facilitate the discovery of novel drug targets.

Kovacic, Sanja; Bakran, Mirjana

2012-01-01

8

Genetic background of febrile seizures.  

PubMed

Febrile seizures (FSs) occur in children older than 1 month and without prior afebrile seizures in the absence of a central nervous system infection or acute electrolyte imbalance. Their pathogenesis is multifactorial. The most relevant familial studies evidence an occurrence rate ranging from 10% to 46% and median recurrence rate of 36% in children with positive familial history for FS. The main twin studies demonstrated a higher concordance rate in monozygotic twins with FS than in dizygotic ones. Linkage studies have proposed 11 chromosomal locations responsible to FS attributed to FEB1 to FEB11. Population-based association studies have shown at least one positive association for 14 of 41 investigated genes with FS. The proinflammatory cytokine interleukin 1? (IL-1?) was the most investigated and also gene associated with susceptibility to FS. A possible role in the overlapping of epilepsy and FS was found for 16 of 36 investigated genes. SCN1A, IL-1?, CHRNA4, and GABRG2 were the most commonly involved genes in this context. The genetic background of FS involves the regulation of different processes, including individual and familial susceptibility, modulation of immune response, and neuronal excitability and interactions with exogenous agents such as viruses. PMID:24399675

Saghazadeh, Amene; Mastrangelo, Mario; Rezaei, Nima

2014-01-01

9

Interaction between DMRT1 function and genetic background modulates signaling and pluripotency to control tumor susceptibility in the fetal germ line  

PubMed Central

Dmrt1(doublesex and mab-3 related transcription factor 1) is a regulator of testis development in vertebrates that has been implicated in testicular germ cell tumors of mouse and human. In the fetal mouse testis Dmrt1 regulates germ cell pluripotency in a strain-dependent manner. Loss of Dmrt1 in 129Sv strain mice results in a >90% incidence of testicular teratomas, tumors consisting cells of multiple germ layers; by contrast, these tumors have never been observed in Dmrt1 mutants of C57BL/6J (B6) or mixed genetic backgrounds. To further investigate the interaction between Dmrt1 and genetic background we compared mRNA expression in wild type and Dmrt1 mutant fetal testes of 129Sv and B6 mice at embryonic day 15.5 (E15.5), prior to overt tumorigenesis. Loss of Dmrt1 caused misexpression of overlapping but distinct sets of mRNAs in the two strains. The mRNAs that were selectively affected included some that changed expression only in one strain or the other and some that changed in both strains but to a greater degree in one versus the other. In particular, loss of Dmrt1 in 129Sv testes caused a more severe failure to silence regulators of pluripotency than in B6 testes. A number of genes misregulated in 129Sv mutant testes also are misregulated in human testicular germ cell tumors (TGCTs), suggesting similar etiology between germ cell tumors in mouse and man. Expression profiling showed that DMRT1 also regulates pluripotency genes in the fetal ovary, although Dmrt1 mutant females do not develop teratomas. Pathway analysis indicated disruption of several signaling pathways in Dmrt1 mutant fetal testes, including Nodal, Notch, and GDNF. We used a Nanos3-cre knock-in allele to perform conditional gene targeting, testing the GDNF coreceptors Gfra1 and Ret for effects on teratoma susceptibility. Conditional deletion of Gfra1 but not Ret in fetal germ cells of animals outcrossed to 129Sv caused a modest but significant elevation in tumor incidence. Despite some variability in genetic background in these crosses, this result is consistent with previous genetic mapping of teratoma susceptibility loci to the region containing Gfra1. Using Nanos3-cre we also uncovered a strong genetic interaction between Dmrt1 and Nanos3, suggesting parallel functions for these two genes in fetal germ cells. Finally, we used chromatin immunoprecipitation (ChIP-seq) analysis to identify a number of potentially direct DMRT1 targets. This analysis suggested that DMRT1 controls pluripotency via transcriptional repression of Esrrb, Nr5a2/Lrh1, and Sox2. Given the strong evidence for involvement of DMRT1 in human TGCT, the downstream genes and pathways identified in this study provide potentially useful candidates for roles in the human disease.

Krentz, Anthony D.; Murphy, Mark W.; Zhang, Teng; Sarver, Aaron L.; Jain, Sanjay; Griswold, Michael D.; Bardwell, Vivian J.; Zarkower, David

2013-01-01

10

Genetic Architecture of Intrinsic Antibiotic Susceptibility  

Microsoft Academic Search

Background: Antibiotic exposure rapidly selects for more resistant bacterial strains, and both a drug's chemical structure and a bacterium's cellular network affect the types of mutations acquired. Methodology\\/Principal Findings: To better characterize the genetic determinants of antibiotic susceptibility, we exposed a transposon-mutagenized library of Escherichia coli to each of 17 antibiotics that encompass a wide range of drug classes and

Hany S. Girgis; Alison K. Hottes; Saeed Tavazoie

2009-01-01

11

Genetic background of multiple sclerosis.  

PubMed

Multiple sclerosis (MS) is a one of the group of diseases labeled as "common complex". Virtually all common complex traits, genetic and environmental components have important roles, both independently and interactively, in disease susceptibility and stochastic and epigenetic effects cannot be overlooked. Data presented are largely part of the Canada-wide prospective, population-based longitudinal Canadian Collaborative Project on Genetic Susceptibility to MS (CCPGSMS) which includes over 30,000 unique families having at least 1 member with MS. Findings do not support a general propensity to autoimmune disease in MS families, but clearly highlight the importance of controlling for gender (patient, informant) when conducting such studies. The MHC class II association has been fine-mapped to the HLA-DRB5*0101-HLA-DRB1*1501-HLA-DQA1*0102-HLA-DQB1*0602 extended haplotype. This HLA haplotype confers a relative risk of approximately 3 and homozygosity for this haplotype increases the risk by over 6 fold. However, the HLA haplotype loci interactions are complex and include, epistasis, trans and cis effects, and parent-of-origin effects. As well, there may be interactions of EBV and vitamin D with the HLA, In conclusion, using MS as an example, susceptibility for common complex disease most likely results from interactions of genes, environmental interactions and gene/environment interactions. PMID:21619948

Sadovnick, A Dessa

2012-01-01

12

Genetic susceptibility to childhood leukaemia  

PubMed Central

The aetiology of leukaemias among children is believed to be distinct from that of adults, mainly due to the clearer role for early life exposures, including those in utero. However, few risk factors have been established, because of the challenge of studying a disease with relatively low incidence. Identified risk factors, including ionizing radiation, chemotherapeutic agents and specific genetic abnormalities, explain <10% of incidence(1,2). Although the causes for the remaining 90% are unknown, it is possible that genetic susceptibility factors, either alone or in conjunction with environmental factors, may be involved. In this paper, the authors (a) review the evidence surrounding genetic susceptibility factors, with emphasis on the genes' main effects; (b) review some recent developments in the Northern California Childhood Leukaemia Study (NCCLS) as a case study of design and practical considerations in genetic epidemiology research and (c) highlight both challenges and future directions in this exciting research area.

Chokkalingam, Anand P.; Buffler, Patricia A.

2008-01-01

13

Genetic susceptibility to Grave's disease.  

PubMed

The variety of clinical presentations of eye changes in patients with Graves' disease (GD) suggests that complex interactions between genetic, environmental, endogenous and local factors influence the severity of Graves' ophthalmopathy (GO). It is thought that the development of GO might be influenced by genetic factors and environmental factors, such as cigarette smoking. At present, however, the role of genetic factors in the development of GO is not known. On the basis of studies with candidate genes and other genetic approaches, several susceptibility loci in GO have been proposed, including immunological genes, human leukocyte antigen (HLA), cytotoxic T-lymphocyte antigen-4 (CTLA-4), regulatory T-cell genes and thyroid-specific genes. This review gives a brief overview of the current range of major susceptibility genes found for GD. PMID:23747868

Li, Hong; Chen, Qiuying

2013-01-01

14

[Genetic background of juvenile idiopathic arthritis].  

PubMed

Several genetic factors have recently been observed as having an influence on susceptibility, course and prognosis of juvenile idiopathic arthritis (JIA): 1. Affected sib pairs were observed to have a low concordance in terms of disease incidence, but significant concordance in terms of subtype and course of disease. 2. Each subtype of JIA was observed to have a distinct genetic background. 3. Some JIA patients do not carry any of the defined risk genes. 4. Most subtypes of JIA have a distinct different genetic background to rheumatoid arthritis in adults. 5. Multiple factors have been observed to be involved in pathogenesis implying genetic and environmental factors. 6. Systemic JIA differs from all other subtypes in terms of genetic background and treatment options. It is currently assumed to be an autoinflammatory disease. 7. Genetic factors not only affect the course of the disease, but also response and complication rate. Increasing knowledge on the factors involved in the pathogenesis of JIA as well as analysis of large patient cohorts in consortiums cooperating on an international level have helped define many important polymorphisms; these are currently the subject of further investigation. PMID:20665039

Haas, J P

2010-08-01

15

Genetic susceptibility to substance dependence  

Microsoft Academic Search

Despite what is often believed, the majority of those who experiment with substances with a dependence potential do not develop dependence. However, there is a subpopulation of users that easily becomes dependent on substances, and these individuals exhibit pre-existing comorbid traits, including novelty seeking and antisocial behavior. There appears to be a genetic basis for the susceptibility to dependence and

N Hiroi; S Agatsuma

2005-01-01

16

Genetic susceptibility to radiation  

NASA Astrophysics Data System (ADS)

In the context of space radiation, it is important to know whether the human population includes genetically predisposed radiosensitive subsets. One possibility is that haploinsufficiency for ATM confers radiosensitivity, and this defect involves 1-3% of the population. Using knock-out mice we chose to study cataractogenesis in the lens and oncogenic transformation in mouse embryo fibroblasts to assay for effects of ATM deficiency. Radiation induced cataracts appeared earlier in the heterozygous versus wild-type animals following exposure to either gamma rays or 1 GeV/nucleon iron ions. In addition, it was found that embryo fibroblasts of Atm heterozygotes showed an increased incidence of oncogenic transformation compared with their normal litter-matched counterparts. From these data we suggest that Ataxia Telangiectasia heterozygotes could indeed represent a societally-significant radiosensitive subpopulation.

Hall, E. J.; Brenner, D. J.; Worgul, B.; Smilenov, L.

17

Genetic susceptibility to radiation  

NASA Astrophysics Data System (ADS)

In the context of space radiation, it is important to know whether the human population includes genetically predisposed radiosensitive subsets. One possibility is that haploinsufficiency for ATM confers radiosensitivity, and this defect involves 1 3% of the population. Using knock-out mice we chose to study cataractogenesis in the lens and oncogenic transformation in mouse embryo fibroblasts to assay for effects of ATM deficiency. Radiation induced cataracts appeared earlier in the heterozygous versus wild-type animals following exposure to either gamma rays or 1 GeV/nucleon iron ions. In addition, it was found that embryo fibroblasts of Atm heterozygotes showed an increased incidence of oncogenic transformation compared with their normal litter-matched counterparts. From these data we suggest that Ataxia Telangiectasia heterozygotes could indeed represent a societally significant radiosensitive subpopulation. Knock-out mice are now available for other genes including BRCA1 and 2, and Mrad9. An exciting possibility is the creation of double heterozygotes for pairs of mutated genes that function in the same signal transduction pathway, and consequently confer even greater radiosensitivity.

Hall, E. J.; Brenner, D. J.; Worgul, B.; Smilenov, L.

18

The ontology of genetic susceptibility factors (OGSF) and its application in modeling genetic susceptibility to vaccine adverse events  

PubMed Central

Background Due to human variations in genetic susceptibility, vaccination often triggers adverse events in a small population of vaccinees. Based on our previous work on ontological modeling of genetic susceptibility to disease, we developed an Ontology of Genetic Susceptibility Factors (OGSF), a biomedical ontology in the domain of genetic susceptibility and genetic susceptibility factors. The OGSF framework was then applied in the area of vaccine adverse events (VAEs). Results OGSF aligns with the Basic Formal Ontology (BFO). OGSF defines ‘genetic susceptibility’ as a subclass of BFO:disposition and has a material basis ‘genetic susceptibility factor’. The ‘genetic susceptibility to pathological bodily process’ is a subclasses of ‘genetic susceptibility’. A VAE is a type of pathological bodily process. OGSF represents different types of genetic susceptibility factors including various susceptibility alleles (e.g., SNP and gene). A general OGSF design pattern was developed to represent genetic susceptibility to VAE and associated genetic susceptibility factors using experimental results in genetic association studies. To test and validate the design pattern, two case studies were populated in OGSF. In the first case study, human gene allele DBR*15:01 is susceptible to influenza vaccine Pandemrix-induced Multiple Sclerosis. The second case study reports genetic susceptibility polymorphisms associated with systemic smallpox VAEs. After the data of the Case Study 2 were represented using OGSF-based axioms, SPARQL was successfully developed to retrieve the susceptibility factors stored in the populated OGSF. A network of data from the Case Study 2 was constructed by using ontology terms and individuals as nodes and ontology relations as edges. Different social network analys is (SNA) methods were then applied to verify core OGSF terms. Interestingly, a SNA hub analysis verified all susceptibility alleles of SNPs and a SNA closeness analysis verified the susceptibility genes in Case Study 2. These results validated the proper OGSF structure identified different ontology aspects with SNA methods. Conclusions OGSF provides a verified and robust framework for representing various genetic susceptibility types and genetic susceptibility factors annotated from experimental VAE genetic association studies. The RDF/OWL formulated ontology data can be queried using SPARQL and analyzed using centrality-based network analysis methods.

2014-01-01

19

Genetic susceptibility to lung cancer.  

PubMed

Lung cancer is a highly environmental disease, but cancer researchers have long been interested in investigating genetic susceptibility to lung cancer. This paper is a historical review and provides updated perspectives on lung cancer susceptibility research. The recent introduction of easier genotyping methods and the availability of an almost complete human genome database facilitated the association study to thousands of cases and controls for millions of genetic markers. Discoveries in the field of behavior genetics, that is, the genetic aspects of smoking behavior and nicotine addiction, unexpectedly indicated that polymorphisms in the human central nervous system play an important role in eventually leading to lung cancer. These findings were achieved by using comprehensive approaches, such as a genome, transcriptome, or proteome approach, and the studies were often conducted without a hypothesis. Another-omics approach, the "adductome" or "exposome" approach to how life style information can be integrated into the framework of genetic association studies, has recently emerged. These new paradigms will influence the area of lung cancer risk evaluation in genome cohort studies. PMID:21622282

Sugimura, Haruhiko; Tao, Hong; Suzuki, Masaya; Mori, Hiroki; Tsuboi, Masaru; Matsuura, Shun; Goto, Masanori; Shinmura, Kazuya; Ozawa, Takachika; Tanioka, Fumihiko; Sato, Naomi; Matsushima, Yoshitaka; Kageyama, Shinji; Funai, Kazuhito; Chou, Pei-Hsin; Matsuda, Tomonari

2011-01-01

20

PTPN2 Gene Variants Are Associated with Susceptibility to Both Crohn's Disease and Ulcerative Colitis Supporting a Common Genetic Disease Background  

PubMed Central

Background Genome-wide association studies identified PTPN2 (protein tyrosine phosphatase, non-receptor type 2) as susceptibility gene for inflammatory bowel diseases (IBD). However, the exact role of PTPN2 in Crohn's disease (CD) and ulcerative colitis (UC) and its phenotypic effect are unclear. We therefore performed a detailed genotype-phenotype and epistasis analysis of PTPN2 gene variants. Methodology/Principal Findings Genomic DNA from 2131 individuals of Caucasian origin (905 patients with CD, 318 patients with UC, and 908 healthy, unrelated controls) was analyzed for two SNPs in the PTPN2 region (rs2542151, rs7234029) for which associations with IBD were found in previous studies in other cohorts. Our analysis revealed a significant association of PTPN2 SNP rs2542151 with both susceptibility to CD (p?=?1.95×10?5; OR 1.49 [1.34–1.79]) and UC (p?=?3.87×10?2, OR 1.31 [1.02–1.68]). Moreover, PTPN2 SNP rs7234029 demonstrated a significant association with susceptibility to CD (p?=?1.30×10?3; OR 1.35 [1.13–1.62]) and a trend towards association with UC (p?=?7.53×10?2; OR 1.26 [0.98–1.62]). Genotype-phenotype analysis revealed an association of PTPN2 SNP rs7234029 with a stricturing disease phenotype (B2) in CD patients (p?=?6.62×10?3). Epistasis analysis showed weak epistasis between the ATG16L1 SNP rs2241879 and PTPN2 SNP rs2542151 (p?=?0.024) in CD and between ATG16L1 SNP rs4663396 and PTPN2 SNP rs7234029 (p?=?4.68×10?3) in UC. There was no evidence of epistasis between PTPN2 and NOD2 and PTPN2 and IL23R. In silico analysis revealed that the SNP rs7234029 modulates potentially the binding sites of several transcription factors involved in inflammation including GATA-3, NF-?B, C/EBP, and E4BP4. Conclusions/Significance Our data confirm the association of PTPN2 variants with susceptibility to both CD and UC, suggesting a common disease pathomechanism for these diseases. Given recent evidence that PTPN2 regulates autophagosome formation in intestinal epithelial cells, the potential link between PTPN2 and ATG16L1 should be further investigated.

Seiderer, Julia; Olszak, Torsten; Wetzke, Martin; Beigel, Florian; Tillack, Cornelia; Stallhofer, Johannes; Friedrich, Matthias; Steib, Christian; Goke, Burkhard; Ochsenkuhn, Thomas; Karbalai, Nazanin; Diegelmann, Julia; Czamara, Darina; Brand, Stephan

2012-01-01

21

Genetic Architecture of Intrinsic Antibiotic Susceptibility  

PubMed Central

Background Antibiotic exposure rapidly selects for more resistant bacterial strains, and both a drug's chemical structure and a bacterium's cellular network affect the types of mutations acquired. Methodology/Principal Findings To better characterize the genetic determinants of antibiotic susceptibility, we exposed a transposon-mutagenized library of Escherichia coli to each of 17 antibiotics that encompass a wide range of drug classes and mechanisms of action. Propagating the library for multiple generations with drug concentrations that moderately inhibited the growth of the isogenic parental strain caused the abundance of strains with even minor fitness advantages or disadvantages to change measurably and reproducibly. Using a microarray-based genetic footprinting strategy, we then determined the quantitative contribution of each gene to E. coli's intrinsic antibiotic susceptibility. We found both loci whose removal increased general antibiotic tolerance as well as pathways whose down-regulation increased tolerance to specific drugs and drug classes. The beneficial mutations identified span multiple pathways, and we identified pairs of mutations that individually provide only minor decreases in antibiotic susceptibility but that combine to provide higher tolerance. Conclusions/Significance Our results illustrate that a wide-range of mutations can modulate the activity of many cellular resistance processes and demonstrate that E. coli has a large mutational target size for increasing antibiotic tolerance. Furthermore, the work suggests that clinical levels of antibiotic resistance might develop through the sequential accumulation of chromosomal mutations of small individual effect.

Tavazoie, Saeed

2009-01-01

22

Understanding Cancer Series: Patient's Genetic Background  

Cancer.gov

While attention must be paid to the changes discovered within the genomic profile of a cancerous growth, equal attention must be paid to the intrinsic genetic background of each patient. Cancer does not develop in a vacuum, but within a patient, and each patient's distinctive genetic background results from both intrinsic and extrinsic factors.

23

Genetic background of autoimmune hepatitis in Japan.  

PubMed

Autoimmune hepatitis (AIH) is an organ-specific autoimmune disease characterized by chronic inflammation of the liver. Several studies from ethnically different countries have clarified that the genetic predisposition to type 1 AIH is linked mainly to human leukocyte antigen (HLA)-class II genes. Recently, molecular analysis using polymerase chain reaction (PCR)-based DNA typing has revealed that susceptibility to type 1 AIH is primarily associated with the HLA class II DRB1 locus, which encodes a polymorphic ? chain of the HLA-DR antigen. However, additional susceptibility genes (either HLA or non-HLA) and/or environmental factors may also contribute to the development of type 1 AIH; in Japanese type 1 AIH patients, although the most influential gene in disease susceptibility is HLA-DRB1*04:05, several other genes have been identified as being involved in AIH pathogenesis or resistance and are the currently the focus of single nucleotide polymorphism analysis. PMID:20957499

Yoshizawa, Kaname; Umemura, Takeji; Ota, Masao

2011-01-01

24

Genetic susceptibility to adverse drug reactions  

Microsoft Academic Search

Adverse drug reactions (ADRs) are a major clinical problem. Genetic factors can determine individual susceptibility to both dose-dependent and dose-independent ADRs. Determinants of susceptibility include kinetic factors, such as gene polymorphisms in cytochrome P450 enzymes, and dynamic factors, such as polymorphisms in drug targets. The relative importance of these factors will depend on the nature of the ADR; however, it

Munir Pirmohamed; B. Kevin Park

2001-01-01

25

Genetic susceptibility to ischemic stroke  

PubMed Central

Clinicians who treat patients with stroke need to be aware of several single-gene disorders that have ischemic stroke as a major feature, including sickle cell disease, Fabry disease, cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy, and retinal vasculopathy with cerebral leukodystrophy. The reported genome-wide association studies of ischemic stroke and several related phenotypes (for example, ischemic white matter disease) have shown that no single common genetic variant imparts major risk. Larger studies with samples numbering in the thousands are ongoing to identify common variants with smaller effects on risk. Pharmacogenomic studies have uncovered genetic determinants of response to warfarin, statins and clopidogrel. Despite increasing knowledge of stroke genetics, incorporating this new knowledge into clinical practice remains a challenge. The goals of this article are to review common single-gene disorders relevant to ischemic stroke, summarize the status of candidate gene and genome-wide studies aimed at discovering genetic stroke risk factors, and to briefly discuss pharmacogenomics related to stroke treatment.

Meschia, James F.; Worrall, Bradford B.; Rich, Stephen S.

2014-01-01

26

Genetic susceptibility of cervical cancer  

PubMed Central

Epidemiological and laboratory-based studies have identified infection with one of 15 high-risk human papillomavirus (HPV) types as a necessary but not sufficient cause of cervical cancer. The prevalence of genital HPV infections is high in young women, but most of the infections regress without interventions. Host genetic variations in genes involved in immune response pathways may be related to HPV clearance, and HPV E6/E7 oncoproteins interacting or downstream genes, both coding and non-coding, may contribute to the outcome of high risk HPV infection and cervical cancer. Of specific interest for this review has been the selection of genetic variants in genes involved in the above-referred pathways with a summary of their applications in association studies. Because the supportive and opposing data have been reported in different populations, well-designed international collaborative studies need to be conducted to define the consistency of the associations, paving the way to better define the patients at high risk of developing cervical cancer.

Chen, Xiaojun; Jiang, Jie; Shen, Hongbing; Hu, Zhibin

2011-01-01

27

Genetic Susceptibility to Non-Necrotizing Erysipelas/Cellulitis  

PubMed Central

Background Bacterial non-necrotizing erysipelas and cellulitis are often recurring, diffusely spreading infections of the skin and subcutaneous tissues caused most commonly by streptococci. Host genetic factors influence infection susceptibility but no extensive studies on the genetic determinants of human erysipelas exist. Methods We performed genome-wide linkage with the 10,000 variant Human Mapping Array (HMA10K) array on 52 Finnish families with multiple erysipelas cases followed by microsatellite fine mapping of suggestive linkage peaks. A scan with the HMA250K array was subsequently performed with a subset of cases and controls. Results Significant linkage was found at 9q34 (nonparametric multipoint linkage score (NPLall) 3.84, p?=?0.026), which is syntenic to a quantitative trait locus for susceptibility to group A streptococci infections on chromosome 2 in mouse. Sequencing of candidate genes in the 9q34 region did not conclusively associate any to erysipelas/cellulitis susceptibility. Suggestive linkage (NPLall>3.0) was found at three loci: 3q22-24, 21q22, and 22q13. A subsequent denser genome scan with the HMA250K array supported the 3q22 locus, in which several SNPs in the promoter of AGTR1 (Angiotensin II receptor type I) suggestively associated with erysipelas/cellulitis susceptibility. Conclusions Specific host genetic factors may cause erysipelas/cellulitis susceptibility in humans.

Hannula-Jouppi, Katariina; Massinen, Satu; Siljander, Tuula; Makela, Siru; Kivinen, Katja; Leinonen, Rasko; Jiao, Hong; Aitos, Paivi; Karppelin, Matti; Vuopio, Jaana; Syrjanen, Jaana; Kere, Juha

2013-01-01

28

Genetic Susceptibility in Inflammatory Bowel Disease  

Microsoft Academic Search

The genetic susceptibility is clearly important in the complex inheritance of inflammatory bowel disease (IBD). Furthermore,\\u000a the etiologic basis of the relationship between Crohn’s disease (CD) and ulcerative colitis (UC) is as yet unexplained. The\\u000a strongest evidence supporting the contribution of inherited factors in the pathogenesis of CD and UC comes from concordance\\u000a rates in twin pairs. The development of

Jesús K. Yamamoto-Furusho

2010-01-01

29

Genetic polymorphisms and susceptibility to lung disease  

PubMed Central

Susceptibility to infection by bacterium such as Bacillus anthracis has a genetic basis in mice and may also have a genetic basis in humans. In the limited human cases of inhalation anthrax, studies suggest that not all individuals exposed to anthrax spores were infected, but rather, individuals with underlying lung disease, particularly asthma, sarcoidosis and tuberculosis, might be more susceptible. In this study, we determined if polymorphisms in genes important in innate immunity are associated with increased susceptibility to infectious and non-infectious lung diseases, particularly tuberculosis and sarcoidosis, respectively, and therefore might be a risk factor for inhalation anthrax. Examination of 45 non-synonymous polymorphisms in ten genes: p47phox (NCF1), p67phox (NCF2), p40phox (NCF4), p22phox (CYBA), gp91phox (CYBB), DUOX1, DUOX2, TLR2, TLR9 and alpha 1-antitrypsin (AAT) in a cohort of 95 lung disease individuals and 95 control individuals did not show an association of these polymorphisms with increased susceptibility to lung disease.

Lee, Pauline L; West, Carol; Crain, Karen; Wang, Lei

2006-01-01

30

Genetic polymorphisms linked to susceptibility to malaria  

PubMed Central

The influence of host genetics on susceptibility to Plasmodium falciparum malaria has been extensively studied over the past twenty years. It is now clear that malaria parasites have imposed strong selective forces on the human genome in endemic regions. Different genes have been identified that are associated with different malaria related phenotypes. Factors that promote severity of malaria include parasitaemia, parasite induced inflammation, anaemia and sequestration of parasitized erythrocytes in brain microvasculature. Recent advances in human genome research technologies such as genome-wide association studies (GWAS) and fine genotyping tools have enabled the discovery of several genetic polymorphisms and biomarkers that warrant further study in host-parasite interactions. This review describes and discusses human gene polymorphisms identified thus far that have been shown to be associated with susceptibility or resistance to P. falciparum malaria. Although some polymorphisms play significant roles in susceptibility to malaria, several findings are inconclusive and contradictory and must be considered with caution. The discovery of genetic markers associated with different malaria phenotypes will help elucidate the pathophysiology of malaria and enable development of interventions or cures. Diversity in human populations as well as environmental effects can influence the clinical heterogeneity of malaria, thus warranting further investigations with a goal of developing new interventions, therapies and better management against malaria.

2011-01-01

31

Role of genetic background in induced instability  

NASA Technical Reports Server (NTRS)

Genomic instability is effectively induced by ionizing radiation. Recently, evidence has accumulated supporting a relationship between genetic background and the radiation-induced genomic instability phenotype. This is possibly due to alterations in proteins responsible for maintenance of genomic integrity or altered oxidative metabolism. Studies in human cell lines, human primary cells, and mouse models have been performed predominantly using high linear energy transfer (LET) radiation, or high doses of low LET radiation. The interplay between genetics, radiation response, and genomic instability has not been fully determined at low doses of low LET radiation. However, recent studies using low doses of low LET radiation suggest that the relationship between genetic background and radiation-induced genomic instability may be more complicated than these same relationships at high LET or high doses of low LET radiation. The complexity of this relationship at low doses of low LET radiation suggests that more of the population may be at risk than previously recognized and may have implications for radiation risk assessment.

Kadhim, Munira A.; Nelson, G. A. (Principal Investigator)

2003-01-01

32

The genetic background of uremic secondary hyperparathyroidism.  

PubMed

Many studies have shown how gene mutations and genetic polymorphisms could influence secondary uremic hyperparathyroidism (HPTH), modulating parathyroid (PT) function and hyperplasia. Parathyroid hormone (PTH) gene expression and hormone secretion is regulated mainly by serum calcium, with a post-transcriptional effect, and by vitamin D with a transcriptional effect. PT cells retain the ability to proliferate and to apoptose. Hyperphosphatemia, hypocalcemia and vitamin D deficiency all stimulate PT cell proliferation. In the early stage of chronic uremia, PT proliferation is polyclonal, as in diffuse hyperplasia, whereas nodular hyperplasia growth is monoclonal with an increasingly recognized genetic background. HPTH has been associated with a number of familial diseases, such as multiple endocrine neoplasia-type 1 (MEN1), multiple endocrine neoplasia-type2A (MEN2A), neurofibromatosis type1 (NF1) and HPTH with multiple ossifying jaw fibromas (HPT-JT Syndrome). The genes involved in these diseases have been also investigated in secondary HPTH (sHPTH). Moreover, in sporadic and secondary uremic HPTH, clonal rearrangement and/or oncogene overexpression, gene deletions and tumor suppressor gene inactivation have been reported. However, each condition shows different patterns of genetic abnormalities. Finally, PT function modulation by genetic polymorphisms of vitamin D and calcium receptors and of the PTH gene is reviewed. PMID:16299679

Aucella, Filippo; Morrone, Luigi; Stallone, Carmine; Gesualdo, Loreto

2005-01-01

33

Influence of Genetic Background on Genetically Engineered Mouse Phenotypes  

PubMed Central

The history of mouse genetics, which involves the study of strain-dependent phenotype variability, makes it clear that the genetic background onto which a gene-targeted allele is placed can cause considerable variation in genetically engineered mouse (GEM) phenotype. This variation can present itself as completely different phenotypes, as variations in penetrance of phenotype, or as variable expressivity of phenotype. In this chapter we provide examples from gene-targeting literature showing each of these types of phenotype variation. We discuss ways in which modifier genes can affect the phenotype of a mouse with a mutant gene, and we give examples of modifier locus identification. We also review approaches to minimize gene polymorphism and flanking gene differences between experimental animals, and between them and their controls. In addition, we discuss the advantages and disadvantages of performing the first analysis of a knockout mouse on a mixed genetic background. We conclude that a mixed background provides the quickest preview of possible strain-dependent phenotypes (1, 2). Finally, we review recent approaches to improving genetic diversity by generating new inbred strains that encompass a broader range of alleles within the mouse species.

Doetschman, Thomas

2010-01-01

34

Genetic Counseling for Breast Cancer Susceptibility in African American Women.  

National Technical Information Service (NTIS)

Increasingly, the cultural beliefs and values of women are being recognized as important factors in genetic counseling for breast cancer susceptibility. Despite recommendations to increase the cultural sensitivity of genetic counseling, such programs have...

C. Hughes

2006-01-01

35

[Genetic susceptibility for acute high altitude disease].  

PubMed

Acute high altitude disease(AHAD), which can be divided into acute mountain disease (AMS), high altitude pulmonary edema (HAPE) and high altitude cerebral edema (HACE), is one of the special illnesses occurred at high altitude, commonly encountered by travelers to high altitudes (>2 500 m), which affects people's work capacity and health and could be even a life-threatening disease. Despite extensive investigations over the last century, the pathophysiology of AHAD remains elusive. Nevertheless, numerous researches have confirmed the existence of AHAD susceptibility differences. The aim of this paper was to review the epidemiological evidence for a genetic component to the various forms of AHAD so far, as well as to supply helpful reference to its epidemiological studies. PMID:23448926

Zhou, Wen-Ting; Hu, Yang

2013-02-01

36

Genetic Susceptibility to Triple Negative Breast Cancer  

PubMed Central

Triple negative breast cancers (TNBC), defined by the absence of estrogen receptor, progesterone receptor, and human epidermal growth factor receptor-2 expression, account for 12-24% of all breast cancers. TNBC is associated with early recurrence of disease and poor outcome. Germline mutations in the BRCA1 and BRCA2 breast cancer susceptibility genes have been associated with up to 15% of TNBC, and TNBC accounts for 70% of breast tumors arising in BRCA1 mutation carriers and 16-23% of breast tumors in BRCA2 carriers. Whether germline mutations in other breast cancer susceptibility genes also predispose to TNBC remains to be determined. Common variation in a subset of the 72 known breast cancer susceptibility loci identified through genome wide association studies and other large-scale genotyping efforts have also been associated with risk of TNBC (TOX3, ESR1, RAD51L1, TERT, 19p13.1, 20q11, MDM4, 2p24.1, and FTO). Furthermore, variation in the 19p13.1 locus and the MDM4 locus has been associated with TNBC but not other forms of breast cancer suggesting that these are TNBC-specific loci. Thus, TNBC can be distinguished from other breast cancer subtypes by a unique pattern of common and rare germline predisposition alleles. Additional efforts to combine genetic and epidemiological data are needed to better understand the etiology of this aggressive form of breast cancer, to identify prevention and therapeutic targets, and to impact clinical practice through development of risk prediction models.

Stevens, Kristen N.; Vachon, Celine M.; Couch, Fergus J.

2013-01-01

37

The Role of Host Genetics in Susceptibility to Influenza: A Systematic Review  

Microsoft Academic Search

BackgroundThe World Health Organization has identified studies of the role of host genetics on susceptibility to severe influenza as a priority. A systematic review was conducted to summarize the current state of evidence on the role of host genetics in susceptibility to influenza (PROSPERO registration number: CRD42011001380).Methods and FindingsPubMed, Web of Science, the Cochrane Library, and OpenSIGLE were searched using

Peter Horby; Nhu Y. Nguyen; Sarah J. Dunstan; J. Kenneth Baillie

2012-01-01

38

Ontology driven modeling for the knowledge of genetic susceptibility to disease.  

PubMed

For the machine helped exploring the relationships between genetic factors and complex diseases, a well-structured conceptual framework of the background knowledge is needed. However, because of the complexity of determining a genetic susceptibility factor, there is no formalization for the knowledge of genetic susceptibility to disease, which makes the interoperability between systems impossible. Thus, the ontology modeling language OWL was used for formalization in this paper. After introducing the Semantic Web and OWL language propagated by W3C, we applied text mining technology combined with competency questions to specify the classes of the ontology. Then, an N-ary pattern was adopted to describe the relationships among these defined classes. Based on the former work of OGSF-DM (Ontology of Genetic Susceptibility Factors to Diabetes Mellitus), we formalized the definition of "Genetic Susceptibility", "Genetic Susceptibility Factor" and other classes by using OWL-DL modeling language; and a reasoner automatically performed the classification of the class "Genetic Susceptibility Factor". Conclusion: The ontology driven modeling is used for formalization the knowledge of genetic susceptibility to complex diseases. More importantly, when a class has been completely formalized in an ontology, the OWL reasoning can automatically compute the classification of the class, in our case, the class of "Genetic Susceptibility Factors". With more types of genetic susceptibility factors obtained from the laboratory research, our ontologies always needs to be refined, and many new classes must be taken into account to harmonize with the ontologies. Using the ontologies to develop the semantic web needs to be applied in the future. PMID:19628970

Lin, Yu; Sakamoto, Norihiro

2009-01-01

39

Ontology driven modeling for the knowledge of genetic susceptibility to disease.  

PubMed

For the machine helped exploring the relationships between genetic factors and complex diseases, a well-structured conceptual framework of the background knowledge is needed. However, because of the complexity of determining a genetic susceptibility factor, there is no formalization for the knowledge of genetic susceptibility to disease, which makes the interoperability between systems impossible. Thus, the ontology modeling language OWL was used for formalization in this paper. After introducing the Semantic Web and OWL language propagated by W3C, we applied text mining technology combined with competency questions to specify the classes of the ontology. Then, an N-ary pattern was adopted to describe the relationships among these defined classes. Based on the former work of OGSF-DM (Ontology of Genetic Susceptibility Factors to Diabetes Mellitus), we formalized the definition of "Genetic Susceptibility", "Genetic Susceptibility Factor" and other classes by using OWL-DL modeling language; and a reasoner automatically performed the classification of the class "Genetic Susceptibility Factor". Conclusion: The ontology driven modeling is used for formalization the knowledge of genetic susceptibility to complex diseases. More importantly, when a class has been completely formalized in an ontology, the OWL reasoning can automatically compute the classification of the class, in our case, the class of "Genetic Susceptibility Factors". With more types of genetic susceptibility factors obtained from the laboratory research, our ontologies always needs to be refined, and many new classes must be taken into account to harmonize with the ontologies. Using the ontologies to develop the semantic web needs to be applied in the future. PMID:20847592

Lin, Yu; Sakamoto, Norihiro

2009-01-01

40

Genetic polymorphisms and associated susceptibility to asthma  

PubMed Central

As complex common diseases, asthma and allergic diseases are caused by the interaction of multiple genetic variants with a variety of environmental factors. Candidate-gene studies have examined the involvement of a very large list of genes in asthma and allergy, demonstrating a role for more than 100 loci. These studies have elucidated several themes in the biology and pathogenesis of these diseases. A small number of genes have been associated with asthma or allergy through traditional linkage analyses. The publication of the first asthma-focused genome-wide association (GWA) study in 2007 has been followed by nearly 30 reports of GWA studies targeting asthma, allergy, or associated phenotypes and quantitative traits. GWA studies have confirmed several candidate genes and have identified new, unsuspected, and occasionally uncharacterized genes as asthma susceptibility loci. Issues of results replication persist, complicating interpretation and making conclusions difficult to draw, and much of the heritability of these diseases remains undiscovered. In the coming years studies of complex diseases like asthma and allergy will probably involve the use of high-throughput next-generation sequencing, which will bring a tremendous influx of new information as well as new problems in dealing with vast datasets.

March, Michael E; Sleiman, Patrick MA; Hakonarson, Hakon

2013-01-01

41

GENETIC SUSCEPTIBILITY AND EXPERIMENTAL INDUCTION OF PULMONARY DISEASE  

EPA Science Inventory

Genetic Susceptibility and Experimental Induction of Pulmonary Disease. UP Kodavanti, MC Schladweiler, AD Ledbetter, PS Gilmour, P Evansky, KR Smith*, WP Watkinson, DL Costa, KE Pinkerton*. ETD, NHEERL, ORD, US EPA, RTP, NC; *Univ California, Davis, CA, USA. Conventional la...

42

Genetic testing of newborns for type 1 diabetes susceptibility: a prospective cohort study on effects on maternal mental health  

Microsoft Academic Search

BACKGROUND: Concerns about the general psychological impact of genetic testing have been raised. In the Environmental Triggers of Type 1 Diabetes (MIDIA) study, genetic testing was performed for HLA-conferred type 1 diabetes susceptibility among Norwegian newborns. The present study assessed whether mothers of children who test positively suffer from poorer mental health and well-being after receiving genetic risk information about

Kaja K Aas; Kristian Tambs; Marit S Kise; Per Magnus; Kjersti S Rønningen

2010-01-01

43

Genetic analysis of Agrobacterium tumefaciens susceptibility in Brassica oleracea.  

PubMed

The genetic control and heritability of Agrobacterium tumefaciens susceptibility was investigated using a doubled haploid (DH) mapping population of Brassica oleracea and the associated RFLP map. Preliminary studies were carried out by analysis of an 8 x 8 diallel, for which the parental lines were selected to include a range of susceptibilities to A. tumefaciens. The variation observed within the diallel was attributed to both additive and dominant gene effects, with additive gene effects being more important. A broad sense heritability value of 0.95 suggested that 95% of the observed variation was due to genetic effects, with just 5% attributed to non-genetic or environmental effects. A high narrow-sense heritability value of 0.79 suggested that 79% of this trait was controlled by additive gene effects and, therefore, the potential to introduce this trait into breeding material is high. Fifty-nine DH lines from the mapping population were screened for susceptibility towards A. tumefaciens. Variation in susceptibility was observed across the population. The results of the DH screen were entered into the mapping programme MAPQTL and a highly significant quantitative trait loci (QTL) associated with susceptibility to A. tumefaciens was identified on linkage group 09. The use of substitution lines covering this region confirmed the location of this QTL. This work shows that susceptibility to A. tumefaciens is a heritable trait, and the transfer of susceptibility into resistant lines is demonstrated. These findings may help to overcome genotype restrictions to genetic transformation. PMID:14534750

Sparrow, P A C; Townsend, T M; Arthur, A E; Dale, P J; Irwin, J A

2004-02-01

44

Enteropathic spondyloarthropathy: A common genetic background with inflammatory bowel disease?  

PubMed Central

The association between spondyloarthropathy and inflammatory bowel disease (IBD) is largely established, although prevalence is variable because of different population selection and diagnostic methodologies. Most studies indicate that as many as 10%-15% of cases of IBD are complicated by ankylosing spondylitis (AS) or other forms of spondylarthritis (SpA). Of note, ileal inflammation resembling IBD has been reported in up to two thirds of cases of SpA, and it has been suggested that the presence of ileitis is associated with the chronicity of articular complications. Although this observation is of interest to unravel the pathophysiology of the disease, systematic screening of patients with SpA by ileocolonoscopy is not indicated in the absence of gut symptoms, as only a small proportion of patients with subclinical gut inflammation will develop overt IBD over time. The existence of familial clustering of both IBD and AS, the coexistence of both conditions in a patient, the evidence of an increased risk ratio among first- and second-degree relatives of affected AS or IBD patients and finally, the increased cross-risk ratios between AS and IBD, strongly suggest a shared genetic background. So far, however, IL23R is the only identified susceptibility gene shared by both IBD and AS. Although functional studies are still needed to better understand its pathogenic role, great effort is being spent therapeutically targeting this pathway that may prove effective for both disorders.

Colombo, Elisabetta; Latiano, Anna; Palmieri, Orazio; Bossa, Fabrizio; Andriulli, Angelo; Annese, Vito

2009-01-01

45

Bovine tuberculosis: the genetic basis of host susceptibility  

PubMed Central

The prevalence of bovine tuberculosis (BTB) in the UK remains a significant economic burden and problem for the agri-food industry. Much effort has been directed towards improving diagnostics, finding vaccine candidates and assessing the usefulness of badger culling. The contribution that host genotype makes to disease outcome has, until recently, been overlooked; yet, it is biologically untenable that genetic variation does not play a role. In this review, we highlight the evidence, past and present, for a role of host genetics in determining susceptibility to BTB in livestock. We then address some of the major issues surrounding the design of future studies tasked with finding the exact causative genetic variation underpinning the TB susceptibility phenotype. Finally, we discuss some of the potential future benefits, and problems, that a knowledge of the genetic component to BTB resistance/susceptibility may bring to the agricultural industries and the wider scientific community.

Allen, A. R.; Minozzi, G.; Glass, E. J.; Skuce, R. A.; McDowell, S. W. J.; Woolliams, J. A.; Bishop, S. C.

2010-01-01

46

NCI Releases Preliminary Data on Genetic Susceptibility for Prostate Cancer  

Cancer.gov

The National Cancer Institute has released new data from the Cancer Genetic Markers of Susceptibility (CGEMS) study on prostate cancer. This information could help identify genetic factors that influence the disease and will be integral to the discovery and development of new, targeted therapies. This is also the first public release of a whole genome association study of cancer -- such studies examine the entire genome, with no assumptions about which genetic alterations cause cancer.

47

Mice from a Genetically Resistant Background Lacking the Interferon Y Receptor are Susceptible to Infection with Ieishmania major but Mount a Polarized T Helper Cell 1-type CD4 + T Cell Response  

Microsoft Academic Search

Summary Mice with homologous disruption of the gene coding for the ligand-binding chain of the interferon (IFN) 3' receptor and derived from a strain genetically resistant to infection with Leishmania major have been used to study further the role of this cytokine in the differentiation of functional CD4 + T cell subsets in vivo and resistance to infection. Wild-type 129\\/Sv\\/Ev

Kristin Swihart; Ulrich Fruth; Nathalie Messmer; Katharina Hug; Reza Behin; Sui Huang; Michel Aguet; Jacques A. Louis

48

Genetic background alters the spectrum of tumors that develop in p53-deficient mice  

Microsoft Academic Search

ABSTRACT,Using,gene,targeting,in embryonic,stem cells, we have generated mice with one or two null pSS germ,line alleles. Mice with both p53 alleles inactivated are,developmentally,normal,but highly susceptible to the early development,of spontaneous,tumors. Initial studies were,performed,in mice,with,a mixed,inbred,genetic background,(75% C57BL\\/6 and,25% 129\\/Sv) (Done- hower et al., Nature (London) 356, 215-221, 1992). To study the effect of genetic background,on tumorigenesis in p53-deficient mice, we have

LAWRENCE A. DONEHOWER; UUMMUNIUAI IUNS

49

A Genetic Basis of Susceptibility to Acute Pyelonephritis  

PubMed Central

Background For unknown reasons, urinary tract infections (UTIs) are clustered in certain individuals. Here we propose a novel, genetically determined cause of susceptibility to acute pyelonephritis, which is the most severe form of UTI. The IL-8 receptor, CXCR1, was identified as a candidate gene when mIL-8Rh mutant mice developed acute pyelonephritis (APN) with severe tissue damage. Methods and Findings We have obtained CXCR1 sequences from two, highly selected APN prone patient groups, and detected three unique mutations and two known polymorphisms with a genotype frequency of 23% and 25% compared to 7% in controls (p<0.001 and p<0.0001, respectively). When reflux was excluded, 54% of the patients had CXCR1 sequence variants. The UTI prone children expressed less CXCR1 protein than the pediatric controls (p<0.0001) and two sequence variants were shown to impair transcription. Conclusions The results identify a genetic innate immune deficiency, with a strong link to APN and renal scarring.

Lundstedt, Ann-Charlotte; McCarthy, Shane; Gustafsson, Mattias C.U.; Godaly, Gabriela; Jodal, Ulf; Karpman, Diana; Leijonhufvud, Irene; Linden, Carin; Martinell, Jeanette; Ragnarsdottir, Bryndis; Samuelsson, Martin; Truedsson, Lennart; Andersson, Bjorn; Svanborg, Catharina

2007-01-01

50

Mice from a genetically resistant background lacking the interferon gamma receptor are susceptible to infection with Leishmania major but mount a polarized T helper cell 1-type CD4+ T cell response  

PubMed Central

Mice with homologous disruption of the gene coding for the ligand- binding chain of the interferon (IFN) gamma receptor and derived from a strain genetically resistant to infection with Leishmania major have been used to study further the role of this cytokine in the differentiation of functional CD4+ T cell subsets in vivo and resistance to infection. Wild-type 129/Sv/Ev mice are resistant to infection with this parasite, developing only small lesions, which resolve spontaneously within 6 wk. In contrast, mice lacking the IFN- gamma receptor develop large, progressing lesions. After infection, lymph nodes (LN) and spleens from both wild-type and knockout mice showed an expansion of CD4+ cells producing IFN-gamma as revealed by measuring IFN-gamma in supernatants of specifically stimulated CD4+ T cells, by enumerating IFN-gamma-producing T cells, and by Northern blot analysis of IFN-gamma transcripts. No biologically active interleukin (IL) 4 was detected in supernatants of in vitro-stimulated LN or spleen cells from infected wild-type or deficient mice. Reverse transcription polymerase chain reaction analysis with primers specific for IL-4 showed similar IL-4 message levels in LN from both types of mice. The IL-4 message levels observed were comparable to those found in similarly infected C57BL/6 mice and significantly lower than the levels found in BALB/c mice. Anti-IFN-gamma treatment of both types of mice failed to alter the pattern of cytokines produced after infection. These data show that even in the absence of IFN-gamma receptors, T helper cell (Th) 1-type responses still develop in genetically resistant mice with no evidence for the expansion of Th2 cells.

1995-01-01

51

Genetic Susceptibility to Fungal Infections in Humans  

PubMed Central

Most fungal infections in humans occur in the setting of iatrogenic immunosuppression or HIV infection. In the absence of these factors, fungi cause mild, self-limited infections that typically involve mucocutaneous surfaces. Hence, when persistent or recurrent mucocutaneous infections (chronic mucocutaneous candidiasis [CMC]) or invasive fungal infections (IFIs) develop in a “normal” host, they are indicative of genetic defects causing innate or adaptive immune dysfunction. In this review, recent developments concerning genetic and immunologic factors that affect the risk for IFIs and CMC are critically discussed.

Lionakis, Michail S.

2012-01-01

52

Genetic aspects of susceptibility to obesity and related dyslipidemias  

Microsoft Academic Search

Obesity has a multifactorial origin. However, although environmental variables undoubtedly play a role in the development of obesity, it is now clear that genetic variation is also involved in the determination of an individual's susceptibility to body fat accumulation. In addition, it is also widely accepted that obesity is not a single homogeneous phenotype. It is also heterogeneous regarding its

Jean-Pierre Després; Sital Moorjani; Paul J. Lupien; Angelo Tremblay; André Nadeau; Claude Bouchard

1992-01-01

53

Genetic and Genomic Factors Involved in Susceptibility to Lung Disease  

EPA Science Inventory

This chapter has been prepared to be included in a revised edition of The Lung: Development, Aging, and The Environment. It describes genetic and genomic approaches to characterizing susceptibility to environemntal and occupational lung injury in human and animal studies and pres...

54

Genetic Markers of Increased Susceptibility to Diabetic Nephropathy  

Microsoft Academic Search

The effect of exposure to diabetes on the kidney appears to be modulated by genetic factors determining a variable degree of susceptibility to diabetic nephropathy. Multiple loci are probably involved. Some of them might be found among the genes coding for components of the renin angiotensin system (renin, angiotensinogen, angiotensin I-converting enzyme, angiotensin receptors), some may regulate the way in

Alessandro Doria

1998-01-01

55

Host genetic susceptibility, dysbiosis and viral triggers in IBD  

PubMed Central

Purpose of Review Inflammatory bowel disease (IBD) is thought to occur in genetically susceptible individuals. However, environmental factors, potentially including shifts in commensal microbiota, are also required to trigger disease. This review discusses some of the recent discoveries in host susceptibility and interaction with the microbial environment, and pinpoints key areas for advancement in our understanding of IBD pathogenesis. Recent findings Meta-analyses of genome wide association studies have uncovered many new exciting genes associated with susceptibility loci. In addition, improved methods to analyze the commensal microbiota path the way to better define dysbiosis and its potential role in disease. Lastly, identification of viral triggers in experimental systems of IBD suggests a potential role in IBD. Summary Understanding the precise microbial and immune triggers of IBD in a genetic context will hopefully lead to a better understanding of the pathogenesis of this disease and the discovery of novel therapeutic approaches including vaccines for specific viruses.

Sun, Lulu; Nava, Gerardo M.; Stappenbeck, Thaddeus S.

2014-01-01

56

Impact of the Mitochondrial Genetic Background in Complex III Deficiency  

Microsoft Academic Search

BackgroundIn recent years clinical evidence has emphasized the importance of the mtDNA genetic background that hosts a primary pathogenic mutation in the clinical expression of mitochondrial disorders, but little experimental confirmation has been provided. We have analyzed the pathogenic role of a novel homoplasmic mutation (m.15533 A>G) in the cytochrome b (MT-CYB) gene in a patient presenting with lactic acidosis,

Mari Carmen Gil Borlado; David Moreno Lastres; Maritza Gonzalez Hoyuela; Maria Moran; Alberto Blazquez; Rosa Pello; Lorena Marin Buera; Toni Gabaldon; Juan Jose Garcia Peñas; Miguel A. Martín; Joaquin Arenas; Cristina Ugalde

2010-01-01

57

Human genetic susceptibility and infection with Leishmania peruviana  

SciTech Connect

Racial differences, familial clustering, and murine studies are suggestive of host genetic control of Leishmania infections. Complex segregation analysis has been carried out by use of the programs POINTER and COMDS and data from a total population survey, comprising 636 nuclear families, from an L. perurviana endemic area. The data support genetic components controlling susceptibility to clinical leishmaniasis, influencing severity of disease and resistance to disease among healthy individuals. A multifactorial model is favored over a sporadic model. Two-locus models provided the best fit to the data, the optimal model being a recessive gene (frequency .57) plus a modifier locus. Individuals infected at an early age and with recurrent lesions are genetically more susceptible than those infected with a single episode of disease at a later age. Among people with no lesions, those with a positive skin-test response are genetically less susceptible than those with a negative response. The possibility of the involvement of more than one gene together with environmental effects has implications for the design of future linkage studies. 31 refs., 7 tabs.

Shaw, M.A.; Davis, C.R.; Collins, A. [and others

1995-11-01

58

Genetic mapping of tumor susceptibility genes involved in mouse plasmacytomagenesis  

SciTech Connect

Plasmacytomas (PCTs) were induced in 47% of BALB/cAnPt mice by the intraperitoneal injection of pristane, in 2% of (BALB/c [times] DBA/2N)F[sub 1], and in 11% of 773 BALB/cAnPt [times] (BALB/cAnPt [times] DBA/2N)F[sub 1]N[sub 2] backcross mice. This result indicates a multigenic mode of inheritance for PCT susceptibility. To locate genes controlling this complex genetic trait, tumor susceptibility in backcross progeny generated from BALB/c and DBA/2N (resistant) mice was correlated with alleles of 83 marker loci. The genotypes of the PCT-susceptible progeny displayed an excess homozygosity for BALB/c alleles with a 32-centimorgan stretch of mouse chromosome 4 (>95% probability of linkage) with minimal recombination (12%) near Gt10. Another susceptibility gene on mouse chromosome 1 may be linked to Fcgr2 (90% probability of linkage); there were excess heterozygotes for Fcgr2 among the susceptible progeny and excess homozygotes among the resistant progeny. Regions of mouse chromosomes 4 and 1 that are correlated with PCT susceptibility share extensive linkage homology with regions of human chromosome 1 that have been associated with cytogenetic abnormalities in multiple myeloma and lymphoid, breast, and endocrine tumors. 68 refs., 2 figs., 1 tab.

Mock, B.A.; Krall, M.M.; Dosik, J.K. (National Institutes of Health, Bethesda, MD (United States))

1993-10-15

59

Meta-analysis and genome-wide interpretation of genetic susceptibility to drug addiction  

PubMed Central

Background Classical genetic studies provide strong evidence for heritable contributions to susceptibility to developing dependence on addictive substances. Candidate gene and genome-wide association studies (GWAS) have sought genes, chromosomal regions and allelic variants likely to contribute to susceptibility to drug addiction. Results Here, we performed a meta-analysis of addiction candidate gene association studies and GWAS to investigate possible functional mechanisms associated with addiction susceptibility. From meta-data retrieved from 212 publications on candidate gene association studies and 5 GWAS reports, we linked a total of 843 haplotypes to addiction susceptibility. We mapped the SNPs in these haplotypes to functional and regulatory elements in the genome and estimated the magnitude of the contributions of different molecular mechanisms to their effects on addiction susceptibility. In addition to SNPs in coding regions, these data suggest that haplotypes in gene regulatory regions may also contribute to addiction susceptibility. When we compared the lists of genes identified by association studies and those identified by molecular biological studies of drug-regulated genes, we observed significantly higher participation in the same gene interaction networks than expected by chance, despite little overlap between the two gene lists. Conclusions These results appear to offer new insights into the genetic factors underlying drug addiction.

2011-01-01

60

Premature birth and diseases in premature infants: common genetic background?  

PubMed

It has been proposed that during human evolution, development of obligate bipedalism, narrow birth canal cross-sectional area and the large brain have forced an adjustment in duration of pregnancy (scaling of gestational age; Plunkett 2011). Children compared to other mammals are born with proportionally small brains (compared to adult brains), suggesting shortening of pregnancy duration during recent evolution. Prevalence of both obstructed delivery and premature birth is still exceptionally high. In near term infants, functional maturity and viability is high, and gene variants predisposing to respiratory distress syndrome (RDS) are rare. Advanced antenatal and neonatal treatment practices during the new era of medicine allowed survival of also very preterm infants (gestation <32 weeks). Genetic factors may play a major role in predisposing these infants to common pulmonary (bronchopulmonary dysplasia [BPD]; RDS) and intracerebral (intraventricular hemorrhage [IVH], cerebral palsy [CP]) diseases. Fetal genes also influence the susceptibility to preterm labor and premature birth. Specific genes associating with diseases in preterm infants may also contribute to the susceptibility to preterm birth. Understanding and applying the knowledge of genetic interactions in normal and abnormal perinatal-neonatal development requires large, well-structured population cohorts, studies involving the whole genome and international interdisciplinary collaboration. PMID:22385349

Hallman, Mikko

2012-04-01

61

Radiation-sensitive genetically susceptible pediatric sub-populations  

Microsoft Academic Search

Major advances in pediatric cancer treatment have resulted in substantial improvements in survival. However, concern has emerged\\u000a about the late effects of cancer therapy, especially radiation-related second cancers. Studies of childhood cancer patients\\u000a with inherited cancer syndromes can provide insights into the interaction between radiation and genetic susceptibility to\\u000a multiple cancers. Children with retinoblastoma (Rb), neurofibromatosis type 1 (NF1), Li-Fraumeni

Ruth A. Kleinerman

2009-01-01

62

Population genetic analyses of susceptibility to increased body weight  

PubMed Central

Introduction Obesity is a complex condition with multifactorial origin. Assuming that such a state is genetically controlled, the aim of our study was to evaluate the degree of genetic homozygosity among overweight and obese individuals by the homozygously recessive characteristics (HRC) test. Material and methods We analysed the presence, distribution and individual combination of 15 selected genetically controlled recessive phenotype traits in a sample of 140 individuals with increased body mass index (overweight individuals n = 100 and obese individuals n = 40) and a control group of normal weight individuals (n = 300). Results Obese individuals have significantly higher mean values for genetic homozygosity than those with normal weight (normal weight: 3.61 ±1.48; obese: 4.13 ±1.47, p < 0.05) and difference in the presence of certain individual combinations of evaluated phenotype traits (??2 = 76.9; p < 0.01). There was no difference in average homozygosity of such genetic markers between groups of normal weight and overweight individuals (normal weight: 3.61 ±1.48; overweight: 3.93 ±1.51, p > 0.05) and between groups of overweight and obese individuals (overweight: 3.93 ±1.51; obese: 4.13 ±1.47, p > 0.05). There is no difference in the presence of certain individual combinations of evaluated phenotype traits between overweight and obese individuals (??2 = 20.6; p > 0.05). Conclusions There is a populational genetic difference in the degree of genetic homozygosity and variability between the group of normal weight and group of obese individuals, indicating a possible genetic component. Overweight and obese individuals have a genetic predisposition, but different expression of genetic loads could be one of the possible explanations for different susceptibility to increase of fat mass and body mass index.

Cvjeticanin, Suzana; Petronic, Ivana; Milincic, Zeljka; Brdar, Radivoj; Karan, Radmila; Konstantinovic, Ljubica; Dragin, Aleksandra; Cutovic, Milisav

2012-01-01

63

Genetic Background of Escherichia coli and Extended spectrum ? ?-Lactamase Type  

Microsoft Academic Search

To assess the implication of the genetic background of Escherichia coli strains in the emergence of extended- spectrum ?-lactamases (ESBL), 55 TEM-, 52 CTX-M-, and 22 SHV-type ESBL-producing clinical isolates involved in various extraintestinal infections or colonization were stud- ied in terms of phylogenetic group, virulence factor (VF) content (pap, sfa\\/foc, hly, and aer genes), and fluoro- quinolone resistance. A

Catherine Branger; Oana Zamfir; Sabine Geoffroy; Geneviève Laurans; Guillaume Arlet; Hoang Vu Thien; Stéphanie Gouriou; Bertrand Picard; Erick Denamur

64

Identification of Multiple Genetic Susceptibility Loci in Takayasu Arteritis  

PubMed Central

Takayasu arteritis is a rare inflammatory disease of large arteries. The etiology of Takayasu arteritis remains poorly understood, but genetic contribution to the disease pathogenesis is supported by the genetic association with HLA-B?52. We genotyped ?200,000 genetic variants in two ethnically divergent Takayasu arteritis cohorts from Turkey and North America by using a custom-designed genotyping platform (Immunochip). Additional genetic variants and the classical HLA alleles were imputed and analyzed. We identified and confirmed two independent susceptibility loci within the HLA region (r2 < 0.2): HLA-B/MICA (rs12524487, OR = 3.29, p = 5.57 × 10?16) and HLA-DQB1/HLA-DRB1 (rs113452171, OR = 2.34, p = 3.74 × 10?9; and rs189754752, OR = 2.47, p = 4.22 × 10?9). In addition, we identified and confirmed a genetic association between Takayasu arteritis and the FCGR2A/FCGR3A locus on chromosome 1 (rs10919543, OR = 1.81, p = 5.89 × 10?12). The risk allele in this locus results in increased mRNA expression of FCGR2A. We also established the genetic association between IL12B and Takayasu arteritis (rs56167332, OR = 1.54, p = 2.18 × 10?8).

Saruhan-Direskeneli, Guher; Hughes, Travis; Aksu, Kenan; Keser, Gokhan; Coit, Patrick; Aydin, Sibel Z.; Alibaz-Oner, Fatma; Kamal?, Sevil; Inanc, Murat; Carette, Simon; Hoffman, Gary S.; Akar, Servet; Onen, Fatos; Akkoc, Nurullah; Khalidi, Nader A.; Koening, Curry; Karadag, Omer; Kiraz, Sedat; Langford, Carol A.; McAlear, Carol A.; Ozbalkan, Zeynep; Ates, Askin; Karaaslan, Yasar; Maksimowicz-McKinnon, Kathleen; Monach, Paul A.; Ozer, Huseyin T.; Seyahi, Emire; Fresko, Izzet; Cefle, Ayse; Seo, Philip; Warrington, Kenneth J.; Ozturk, Mehmet A.; Ytterberg, Steven R.; Cobankara, Veli; Onat, A. Mesut; Guthridge, Joel M.; James, Judith A.; Tunc, Ercan; Duzgun, Nursen; B?cakc?gil, Muge; Yentur, Sibel P.; Merkel, Peter A.; Direskeneli, Haner; Sawalha, Amr H.

2013-01-01

65

Identification of multiple genetic susceptibility loci in Takayasu arteritis.  

PubMed

Takayasu arteritis is a rare inflammatory disease of large arteries. The etiology of Takayasu arteritis remains poorly understood, but genetic contribution to the disease pathogenesis is supported by the genetic association with HLA-B*52. We genotyped ~200,000 genetic variants in two ethnically divergent Takayasu arteritis cohorts from Turkey and North America by using a custom-designed genotyping platform (Immunochip). Additional genetic variants and the classical HLA alleles were imputed and analyzed. We identified and confirmed two independent susceptibility loci within the HLA region (r(2) < 0.2): HLA-B/MICA (rs12524487, OR = 3.29, p = 5.57 × 10(-16)) and HLA-DQB1/HLA-DRB1 (rs113452171, OR = 2.34, p = 3.74 × 10(-9); and rs189754752, OR = 2.47, p = 4.22 × 10(-9)). In addition, we identified and confirmed a genetic association between Takayasu arteritis and the FCGR2A/FCGR3A locus on chromosome 1 (rs10919543, OR = 1.81, p = 5.89 × 10(-12)). The risk allele in this locus results in increased mRNA expression of FCGR2A. We also established the genetic association between IL12B and Takayasu arteritis (rs56167332, OR = 1.54, p = 2.18 × 10(-8)). PMID:23830517

Saruhan-Direskeneli, Güher; Hughes, Travis; Aksu, Kenan; Keser, Gokhan; Coit, Patrick; Aydin, Sibel Z; Alibaz-Oner, Fatma; Kamal?, Sevil; Inanc, Murat; Carette, Simon; Hoffman, Gary S; Akar, Servet; Onen, Fatos; Akkoc, Nurullah; Khalidi, Nader A; Koening, Curry; Karadag, Omer; Kiraz, Sedat; Langford, Carol A; McAlear, Carol A; Ozbalkan, Zeynep; Ates, Askin; Karaaslan, Yasar; Maksimowicz-McKinnon, Kathleen; Monach, Paul A; Ozer, Hüseyin T; Seyahi, Emire; Fresko, Izzet; Cefle, Ayse; Seo, Philip; Warrington, Kenneth J; Ozturk, Mehmet A; Ytterberg, Steven R; Cobankara, Veli; Onat, A Mesut; Guthridge, Joel M; James, Judith A; Tunc, Ercan; Duzgun, Nur?en; B?cakc?gil, Muge; Yentür, Sibel P; Merkel, Peter A; Direskeneli, Haner; Sawalha, Amr H

2013-08-01

66

Genetic Background Modulates Gene Expression Profile Induced by Skin Irradiation in Ptch1 Mice  

SciTech Connect

Purpose: Ptch1 germ-line mutations in mice predispose to radiation-induced basal cell carcinoma of the skin, with tumor incidence modulated by the genetic background. Here, we examined the possible mechanisms underlying skin response to radiation in F1 progeny of Ptch1{sup neo67/+} mice crossed with either skin tumor-susceptible (Car-S) or -resistant (Car-R) mice and X-irradiated (3 Gy) at 2 days of age or left untreated. Methods and Materials: We conducted a gene expression profile analysis in mRNA samples extracted from the skin of irradiated or control mice, using Affymetrix whole mouse genome expression array. Confirmation of the results was done using real-time reverse-transcriptase polymerase chain reaction. Results: Analysis of the gene expression profile of normal skin of F1 mice at 4 weeks of age revealed a similar basal profile in the nonirradiated mice, but alterations in levels of 71 transcripts in irradiated Ptch1{sup neo67/+} mice of the Car-R cross and modulation of only eight genes in irradiated Ptch1{sup neo67/+} mice of the Car-S cross. Conclusions: These results indicate that neonatal irradiation causes a persistent change in the gene expression profile of the skin. The tendency of mice genetically resistant to skin tumorigenesis to show a more complex pattern of transcriptional response to radiation than do genetically susceptible mice suggests a role for this response in genetic resistance to basal cell tumorigenesis.

Galvan, Antonella; Noci, Sara [Department of Experimental Oncology and Laboratories, Fondazione IRCCS Istituto Nazionale Tumori, Milan (Italy); Mancuso, Mariateresa; Pazzaglia, Simonetta; Saran, Anna [ENEA Laboratories, Rome (Italy); Dragani, Tommaso A. [Department of Experimental Oncology and Laboratories, Fondazione IRCCS Istituto Nazionale Tumori, Milan (Italy)], E-mail: tommaso.dragani@istitutotumori.mi.it

2008-12-01

67

TGF-alpha mediates genetic susceptibility to chronic kidney disease.  

PubMed

The mechanisms of progression of chronic kidney disease (CKD) are poorly understood. Epidemiologic studies suggest a strong genetic component, but the genes that contribute to the onset and progression of CKD are largely unknown. Here, we applied an experimental model of CKD (75% excision of total renal mass) to six different strains of mice and found that only the FVB/N strain developed renal lesions. We performed a genome-scan analysis in mice generated by back-crossing resistant and sensitive strains; we identified a major susceptibility locus (Ckdp1) on chromosome 6, which corresponds to regions on human chromosome 2 and 3 that link with CKD progression. In silico analysis revealed that the locus includes the gene encoding the EGF receptor (EGFR) ligand TGF-?. TGF-? protein levels markedly increased after nephron reduction exclusively in FVB/N mice, and this increase preceded the development of renal lesions. Furthermore, pharmacologic inhibition of EGFR prevented the development of renal lesions in the sensitive FVB/N strain. These data suggest that variable TGF-? expression may explain, in part, the genetic susceptibility to CKD progression. EGFR inhibition may be a therapeutic strategy to counteract the genetic predisposition to CKD. PMID:21183591

Laouari, Denise; Burtin, Martine; Phelep, Aurélie; Martino, Carla; Pillebout, Evangeline; Montagutelli, Xavier; Friedlander, Gérard; Terzi, Fabiola

2011-02-01

68

TGF-? Mediates Genetic Susceptibility to Chronic Kidney Disease  

PubMed Central

The mechanisms of progression of chronic kidney disease (CKD) are poorly understood. Epidemiologic studies suggest a strong genetic component, but the genes that contribute to the onset and progression of CKD are largely unknown. Here, we applied an experimental model of CKD (75% excision of total renal mass) to six different strains of mice and found that only the FVB/N strain developed renal lesions. We performed a genome-scan analysis in mice generated by back-crossing resistant and sensitive strains; we identified a major susceptibility locus (Ckdp1) on chromosome 6, which corresponds to regions on human chromosome 2 and 3 that link with CKD progression. In silico analysis revealed that the locus includes the gene encoding the EGF receptor (EGFR) ligand TGF-?. TGF-? protein levels markedly increased after nephron reduction exclusively in FVB/N mice, and this increase preceded the development of renal lesions. Furthermore, pharmacologic inhibition of EGFR prevented the development of renal lesions in the sensitive FVB/N strain. These data suggest that variable TGF-? expression may explain, in part, the genetic susceptibility to CKD progression. EGFR inhibition may be a therapeutic strategy to counteract the genetic predisposition to CKD.

Laouari, Denise; Burtin, Martine; Phelep, Aurelie; Martino, Carla; Pillebout, Evangeline; Montagutelli, Xavier; Friedlander, Gerard

2011-01-01

69

Genetic background affects induced pluripotent stem cell generation  

PubMed Central

Introduction The influence of genetic background on the ability to generate induced pluripotent stem cells (iPSCs) has the potential to impact future applications, but has yet to be examined in detail. The purpose of this study was to determine if genetic background affects the efficiency of generating iPSCs during early reprograming as well as the pluripotent stability of the iPSCs during later stages of reprograming. Methods Mouse embryonic fibroblasts (MEFs) were isolated from six strains of mice (NON/LtJ; C57BL/6J; DBA/2J; BALB/cJ; 129S1/SvlmJ; CAST/EiJ) that were selected based on genetic diversity and differences in ability to produce embryonic stem cell (ESC) lines. MEFs were reprogramed via doxycycline-inducible lentiviral transduction of murine Oct4, Klf4, Sox2, and c-Myc. Differences in efficiency to generate iPSCs were assessed by comparing the total number of colonies, the percentage of colonies positive for alkaline phosphatase staining and the percentage of cells positive for SSEA1. iPSC colonies were expanded to establish doxycycline-independent cell lines whose pluripotency was then evaluated via ability to form teratomas in NOD.CB17-Prkdcscid/J mice. Proliferation of non-transduced parent MEFs from each strain was also examined over ten days under conditions that simulated reprograming. Results NON/LtJ and CAST/EiJ strains were more efficient than other strains in generating iPSCs for all parameters measured and parent MEFs from these strains were more proliferative than those from other strains. Doxycycline-independent iPSC lines were established using standard conditions for all strains except BALB/cJ, which required a higher concentration (5x) of leukemia inhibitory factor (LIF). iPSCs from all strains were capable of producing teratomas in NOD.CB17-Prkdcscid/J mice. Conclusions The results of this study suggest that genetic background does affect iPSC generation and pluripotent stability. In addition, our results demonstrate that strain differences in efficiency to generate iPSCs during the early stages of reprograming are correlated with those observed in proliferation of parent MEFs. These findings have important implications both for future iPSC applications as well as for future investigation into determining the genes responsible for reprograming efficiency and stability.

2012-01-01

70

Radiation-sensitive genetically susceptible pediatric sub-populations.  

PubMed

Major advances in pediatric cancer treatment have resulted in substantial improvements in survival. However, concern has emerged about the late effects of cancer therapy, especially radiation-related second cancers. Studies of childhood cancer patients with inherited cancer syndromes can provide insights into the interaction between radiation and genetic susceptibility to multiple cancers. Children with retinoblastoma (Rb), neurofibromatosis type 1 (NF1), Li-Fraumeni syndrome (LFS), and nevoid basal cell carcinoma syndrome (NBCCS) are at substantial risk of developing radiation-related second and third cancers. A radiation dose-response for bone and soft-tissue sarcomas has been observed in hereditary Rb patients, with many of these cancers occurring in the radiation field. Studies of NF1 patients irradiated for optic pathway gliomas have reported increased risks of developing another cancer associated with radiotherapy. High relative risks for second and third cancers were observed for a cohort of 200 LFS family members, especially children, possibly related to radiotherapy. Children with NBCCS are very sensitive to radiation and develop multiple basal cell cancers in irradiated areas. Clinicians following these patients should be aware of their increased genetic susceptibility to multiple primary malignancies enhanced by sensitivity to ionizing radiation. PMID:19083227

Kleinerman, Ruth A

2009-02-01

71

Genetic susceptibility variants associated with colorectal cancer prognosis.  

PubMed

Colorectal cancer (CRC) is the second leading cause of cancer-related death among men and women in Western countries. Once a tumour develops, a differentiated prognosis could be determined by lifestyle habits or inherited and somatic genetic factors. Finding such prognostic factors will be helpful in order to identify cases with a shorter survival or at a higher risk of recurrence that may benefit from more intensive treatment and follow-up surveillance. Sixteen CRC genetic susceptibility variants were directly genotyped in a cohort of 1235 CRC patients recruited by the EPICOLON Spanish consortium. Univariate Cox and multivariate regression analyses were performed taking as primary outcomes overall survival (OS), disease-free survival and recurrence-free interval. Genetic variants rs9929218 at 16q22.1 and rs10795668 at 10p14 may have an effect on OS. The G allele of rs9929218 was linked with a better OS [GG genotype, genotypic model: hazard ratio (HR) = 0.65, 95% confidence interval (CI) 0.45-0.93, P = 0.0179; GG/GA genotypes, dominant model: HR = 0.66, 95% CI 0.47-0.94, P = 0.0202]. Likewise, the G allele of rs10795668 was associated with better clinical outcome (GG genotype, genotypic model: HR = 0.73, 95% CI 0.53-1.01, P = 0.0570; GA genotype, genotypic model: HR = 0.66, 95% CI 0.47-0.92, P = 0.0137; GG/GA genotypes, dominant model: HR = 0.68, 95% CI 0.50-0.94, P = 0.0194). In conclusion, CRC susceptibility variants rs9929218 and rs10795668 may exert some influence in modulating patient's survival and they deserve to be further tested in additional CRC cohorts in order to confirm their potential as prognosis or predictive biomarkers. PMID:23712746

Abulí, Anna; Lozano, Juan José; Rodríguez-Soler, María; Jover, Rodrigo; Bessa, Xavier; Muñoz, Jenifer; Esteban-Jurado, Clara; Fernández-Rozadilla, Ceres; Carracedo, Angel; Ruiz-Ponte, Clara; Cubiella, Joaquín; Balaguer, Francesc; Bujanda, Luis; Reñé, Josep M; Clofent, Juan; Morillas, Juan Diego; Nicolás-Pérez, David; Xicola, Rosa M; Llor, Xavier; Piqué, Josep M; Andreu, Montserrat; Castells, Antoni; Castellví-Bel, Sergi

2013-10-01

72

Phenotypic associations of genetic susceptibility loci in systemic lupus erythematosus  

PubMed Central

Objective Systemic lupus erythematosus is a clinically heterogeneous autoimmune disease. A number of genetic loci that increase lupus susceptibility have been established. This study examines if these genetic loci also contribute to the clinical heterogeneity in lupus. Materials and methods 4001 European-derived, 1547 Hispanic, 1590 African-American and 1191 Asian lupus patients were genotyped for 16 confirmed lupus susceptibility loci. Ancestry informative markers were genotyped to calculate and adjust for admixture. The association between the risk allele in each locus was determined and compared in patients with and without the various clinical manifestations included in the ACR criteria. Results Renal disorder was significantly correlated with the lupus risk allele in ITGAM (p=5.0×10?6, OR 1.25, 95% CI 1.12 to 1.35) and in TNFSF4 (p=0.0013, OR 1.14, 95% CI 1.07 to 1.25). Other significant findings include the association between risk alleles in FCGR2A and malar rash (p=0.0031, OR 1.11, 95% CI 1.17 to 1.33), ITGAM and discoid rash (p=0.0020, OR 1.20, 95% CI 1.06 to 1.33), STAT4 and protection from oral ulcers (p=0.0027, OR 0.89, 95% CI 0.83 to 0.96) and IL21 and haematological disorder (p=0.0027, OR 1.13, 95% CI 1.04 to 1.22). All these associations are significant with a false discovery rate of <0.05 and pass the significance threshold using Bonferroni correction for multiple testing. Conclusion Significant associations were found between lupus clinical manifestations and the FCGR2A, ITGAM, STAT4, TNSF4 and IL21 genes. The findings suggest that genetic profiling might be a useful tool to predict disease manifestations in lupus patients in the future.

Sanchez, Elena; Nadig, Ajay; Richardson, Bruce C; Freedman, Barry I; Kaufman, Kenneth M; Kelly, Jennifer A; Niewold, Timothy B; Kamen, Diane L; Gilkeson, Gary S; Ziegler, Julie T; Langefeld, Carl D; Alarcon, Graciela S; Edberg, Jeffrey C; Ramsey-Goldman, Rosalind; Petri, Michelle; Brown, Elizabeth E; Kimberly, Robert P; Reveille, John D; Vila, Luis M; Merrill, Joan T; Anaya, Juan-Manuel; James, Judith A; Pons-Estel, Bernardo A; Martin, Javier; Park, So-Yeon; Bang, So-Young; Bae, Sang-Cheol; Moser, Kathy L; Vyse, Timothy J; Criswell, Lindsey A; Gaffney, Patrick M; Tsao, Betty P; Jacob, Chaim O; Harley, John B; Alarcon-Riquelme, Marta E; Sawalha, Amr H

2011-01-01

73

New application of intelligent agents in sporadic amyotrophic lateral sclerosis identifies unexpected specific genetic background  

PubMed Central

Background Few genetic factors predisposing to the sporadic form of amyotrophic lateral sclerosis (ALS) have been identified, but the pathology itself seems to be a true multifactorial disease in which complex interactions between environmental and genetic susceptibility factors take place. The purpose of this study was to approach genetic data with an innovative statistical method such as artificial neural networks to identify a possible genetic background predisposing to the disease. A DNA multiarray panel was applied to genotype more than 60 polymorphisms within 35 genes selected from pathways of lipid and homocysteine metabolism, regulation of blood pressure, coagulation, inflammation, cellular adhesion and matrix integrity, in 54 sporadic ALS patients and 208 controls. Advanced intelligent systems based on novel coupling of artificial neural networks and evolutionary algorithms have been applied. The results obtained have been compared with those derived from the use of standard neural networks and classical statistical analysis Results Advanced intelligent systems based on novel coupling of artificial neural networks and evolutionary algorithms have been applied. The results obtained have been compared with those derived from the use of standard neural networks and classical statistical analysis. An unexpected discovery of a strong genetic background in sporadic ALS using a DNA multiarray panel and analytical processing of the data with advanced artificial neural networks was found. The predictive accuracy obtained with Linear Discriminant Analysis and Standard Artificial Neural Networks ranged from 70% to 79% (average 75.31%) and from 69.1 to 86.2% (average 76.6%) respectively. The corresponding value obtained with Advanced Intelligent Systems reached an average of 96.0% (range 94.4 to 97.6%). This latter approach allowed the identification of seven genetic variants essential to differentiate cases from controls: apolipoprotein E arg158cys; hepatic lipase -480 C/T; endothelial nitric oxide synthase 690 C/T and glu298asp; vitamin K-dependent coagulation factor seven arg353glu, glycoprotein Ia/IIa 873 G/A and E-selectin ser128arg. Conclusion This study provides an alternative and reliable method to approach complex diseases. Indeed, the application of a novel artificial intelligence-based method offers a new insight into genetic markers of sporadic ALS pointing out the existence of a strong genetic background.

Penco, Silvana; Buscema, Massimo; Patrosso, Maria Cristina; Marocchi, Alessandro; Grossi, Enzo

2008-01-01

74

Contribution of Environment and Genetics to Pancreatic Cancer Susceptibility  

PubMed Central

Several risk factors have been identified as potential contributors to pancreatic cancer development, including environmental and lifestyle factors, such as smoking, drinking and diet, and medical conditions such as diabetes and pancreatitis, all of which generate oxidative stress and DNA damage. Oxidative stress status can be modified by environmental factors and also by an individual's unique genetic makeup. Here we examined the contribution of environment and genetics to an individual's level of oxidative stress, DNA damage and susceptibility to pancreatic cancer in a pilot study using three groups of subjects: a newly diagnosed pancreatic cancer group, a healthy genetically-unrelated control group living with the case subject, and a healthy genetically-related control group which does not reside with the subject. Oxidative stress and DNA damage was evaluated by measuring total antioxidant capacity, direct and oxidative DNA damage by Comet assay, and malondialdehyde levels. Direct DNA damage was significantly elevated in pancreatic cancer patients (age and sex adjusted mean ± standard error: 1.00±0.05) versus both healthy unrelated and related controls (0.70±0.06, p<0.001 and 0.82±0.07, p?=?0.046, respectively). Analysis of 22 selected SNPs in oxidative stress and DNA damage genes revealed that CYP2A6 L160H was associated with pancreatic cancer. In addition, DNA damage was found to be associated with TNFA ?308G>A and ERCC4 R415Q polymorphisms. These results suggest that measurement of DNA damage, as well as select SNPs, may provide an important screening tool to identify individuals at risk for development of pancreatic cancer.

Hocevar, Barbara A.; Kamendulis, Lisa M.; Pu, Xinzhu; Perkins, Susan M.; Wang, Zheng-Yu; Johnston, Erica L.; DeWitt, John M.; Li, Lang; Loehrer, Patrick J.; Klaunig, James E.; Chiorean, E. Gabriela

2014-01-01

75

Contribution of environment and genetics to pancreatic cancer susceptibility.  

PubMed

Several risk factors have been identified as potential contributors to pancreatic cancer development, including environmental and lifestyle factors, such as smoking, drinking and diet, and medical conditions such as diabetes and pancreatitis, all of which generate oxidative stress and DNA damage. Oxidative stress status can be modified by environmental factors and also by an individual's unique genetic makeup. Here we examined the contribution of environment and genetics to an individual's level of oxidative stress, DNA damage and susceptibility to pancreatic cancer in a pilot study using three groups of subjects: a newly diagnosed pancreatic cancer group, a healthy genetically-unrelated control group living with the case subject, and a healthy genetically-related control group which does not reside with the subject. Oxidative stress and DNA damage was evaluated by measuring total antioxidant capacity, direct and oxidative DNA damage by Comet assay, and malondialdehyde levels. Direct DNA damage was significantly elevated in pancreatic cancer patients (age and sex adjusted mean ± standard error: 1.00 ± 0.05) versus both healthy unrelated and related controls (0.70 ± 0.06, p<0.001 and 0.82 ± 0.07, p = 0.046, respectively). Analysis of 22 selected SNPs in oxidative stress and DNA damage genes revealed that CYP2A6 L160H was associated with pancreatic cancer. In addition, DNA damage was found to be associated with TNFA -308G>A and ERCC4 R415Q polymorphisms. These results suggest that measurement of DNA damage, as well as select SNPs, may provide an important screening tool to identify individuals at risk for development of pancreatic cancer. PMID:24651674

Hocevar, Barbara A; Kamendulis, Lisa M; Pu, Xinzhu; Perkins, Susan M; Wang, Zheng-Yu; Johnston, Erica L; DeWitt, John M; Li, Lang; Loehrer, Patrick J; Klaunig, James E; Chiorean, E Gabriela

2014-01-01

76

Genetic, clinical and radiographic signs in knee osteoarthritis susceptibility  

PubMed Central

Introduction Osteoarthritis (OA) is considered to be a multifactorial and polygenic disease and diagnosis is mainly clinical and radiological. Correlation between radiographic data and clinical status has been reported. However, very few studies, especially in Caucasian people, describe the association between the Kellgren and Lawrence OA grading scale (KL) and genetic alterations to better understand OA etiopathogenesis and susceptibility. In order to update the knee OA grading, in this study we assessed the associations between KL grade, clinical features such as American Knee Society Score (AKSS), age, and polymorphisms in the principal osteoarthritis susceptibility (OS) genes in Sicilian individuals. Methods In 66 Sicilian individuals affected by primary knee OA, the clinical and radiographic evaluation was performed using 2 sub-scores of AKSS (knee score (KS) and function score (FS)) and KL. The patients were also classified according to age. Online Mendelian Inheritance in Man (OMIM) and Database of Single Nucleotide Polymorphisms (dbSNP) Short Genetic Variations databases were used to select gene regions containing the following polymorphisms to analyze: FRZB rs288326 and rs7775, MATN3 rs77245812, ASPN D14 repeats, PTHR2 rs76758470, GDF5 rs143383 and DVWA rs11718863. Patient genotypes were obtained using Sanger DNA sequencing analysis. Results In our cohort of patients a statistical association between the variables analyzed was reported in all associations tested (KL versus KS, FS and age). We observed that a mild to severe OA radiographic grade is related to severe clinical conditions and loss of articular function and that the severity of symptoms increases with age. Concerning the genotyping analysis, our results revealed a significant statistical association between KL grading and GDF5 rs143383 and DVWA rs11718863 genetic alterations. The latter was also associated with a more severe radiographic grade, displaying its predictive role as OA marker progression. Statistically significant association between clinical, radiographic and genetic signs observed, suggests extending the actual grading of knee OA based mainly on X-ray features. Conclusions This work represents a multidisciplinary and translational medicine approach to study OA where clinical, radiological, and OS5 and OS6 SNPs evaluation could contribute to better define grading and progression of OA and to the development of new therapies.

2014-01-01

77

Influence of genetic background on host resistance to experimental murine tularemia.  

PubMed Central

The host response to experimental murine tularemia was examined in different inbred mouse strains. The kinetics of growth of Francisella tularensis live vaccine strain (LVS) in the livers and spleens of A and C57BL/6 mice were monitored, and it was observed that mice of the A strain were more susceptible to the proliferation of LVS than were C57BL/6 mice. The difference was most marked 5 days following infection, when the number of bacteria isolated from the spleens of A mice was found to exceed that of C57BL/6 mice by 100-fold. In addition, the C57BL/6 strain exhibited a more pronounced splenomegaly 8 days after infection than did the A strain. When the response of other inbred strains was evaluated by determining the splenic count of LVS on day 5 postinfection, several levels of antiularemic resistance were observed. Mice of the AKR, BALB/cBy, C57BL/10, and SJL strains were found to be most resistant, while SM mice were most susceptible to the proliferation of LVS. The DBA/2, CBA, 129, C3H/HeJ, and A strains expressed a resistance phenotype which was intermediate between the two extremes, with A and C3H/HeJ mice being somewhat more susceptible than DBA/2, CBA, or 129 mice. The trait of resistance or susceptibility was analyzed genetically in (C57BL/6 x A)F1 hybrid mice and in F2 generation and recombinant inbred (RI) mouse strains derived from C57BL/6 (resistant) and A (susceptible) strain progenitors. The F1 progeny exhibited a level of resistance to infection which was similar to that of the resistant parent. In both the F2 generation mice and the RI strains, a continuous spectrum of resistance levels was observed. The results of these experiments indicate that the genetic background of the host influences host resistance to experimental murine tularemia and that multiple genetic loci are involved in this response.

Anthony, L S; Skamene, E; Kongshavn, P A

1988-01-01

78

Inherited genetic susceptibility to monoclonal gammopathy of unknown significance.  

PubMed

Monoclonal gammopathy of undetermined significance (MGUS) is present in ?2% of individuals age >50 years. The increased risk of multiple myeloma (MM) in relatives of individuals with MGUS is consistent with MGUS being a marker of inherited genetic susceptibility to MM. Common single-nucleotide polymorphisms (SNPs) at 2p23.3 (rs6746082), 3p22.1 (rs1052501), 3q26.2 (rs10936599), 6p21.33 (rs2285803), 7p15.3 (rs4487645), 17p11.2 (rs4273077), and 22q13.1 (rs877529) have recently been shown to influence MM risk. To examine the impact of these 7 SNPs on MGUS, we analyzed two case-control series totaling 492 cases and 7306 controls. Each SNP independently influenced MGUS risk with statistically significant associations (P < .02) for rs1052501, rs2285803, rs4487645, and rs4273077. SNP associations were independent, with risk increasing with a larger number of risk alleles carried (per allele odds ratio, 1.18; P < 10(-7)). Collectively these data are consistent with a polygenic model of disease susceptibility to MGUS. PMID:24449210

Weinhold, Niels; Johnson, David C; Rawstron, Andrew C; Försti, Asta; Doughty, Chi; Vijayakrishnan, Jayaram; Broderick, Peter; Dahir, Nasrin B; Begum, Dil B; Hosking, Fay J; Yong, Kwee; Walker, Brian A; Hoffmann, Per; Mühleisen, Thomas W; Langer, Christian; Dörner, Elisabeth; Jöckel, Karl-Heinz; Eisele, Lewin; Nöthen, Markus M; Hose, Dirk; Davies, Faith E; Goldschmidt, Hartmut; Morgan, Gareth J; Hemminki, Kari; Houlston, Richard S

2014-04-17

79

HCV Tumor Promoting Effect Is Dependent on Host Genetic Background  

PubMed Central

Background The hepatitis C virus (HCV) is one of the major risk factors for the development of hepatocellular carcinoma (HCC). Nevertheless, transgenic mice which express the whole HCV polyprotein (HCV-Tg) do not develop HCC. Whereas chronic HCV infection causes inflammation in patients, in HCV-Tg mice, the host immune reaction against viral proteins is lacking. We aimed to test the role of HCV proteins in HCC development on the background of chronic inflammation in vivo. Methodology/Principal Findings We crossed HCV-Tg mice that do not develop HCC with the Mdr2-knockout (Mdr2-KO) mice which develop inflammation-associated HCC, to generate Mdr2-KO/HCV-Tg mice. We studied the effect of the HCV transgene on tumor incidence, hepatocyte mitosis and apoptosis, and investigated the potential contributing factors for the generated phenotype by gene expression and protein analyses. The Mdr2-KO/HCV-Tg females from the N2 generation of this breeding (having 75% of the FVB/N genome and 25% of the C57BL/6 genome) produced significantly larger tumors in comparison with Mdr2-KO mice. In parallel, the Mdr2-KO/HCV-Tg females had an enhanced inflammatory gene expression signature. However, in the N7 generation (having 99.2% of the FVB/N genome and 0.8% of the C57BL/6 genome) there was no difference in tumor development between Mdr2-KO/HCV-Tg and Mdr2-KO animals of both sexes. The HCV transgene was similarly expressed in the livers of Mdr2-KO/HCV-Tg females of both generations, as revealed by detection of the HCV transcript and the core protein. Conclusion These findings suggest that the HCV transgene accelerated inflammation-associated hepatocarcinogenesis in a host genetic background-dependent manner.

Klopstock, Naama; Katzenellenbogen, Mark; Pappo, Orit; Sklair-Levy, Miriam; Olam, Devorah; Mizrahi, Lina; Potikha, Tamara; Galun, Eithan; Goldenberg, Daniel

2009-01-01

80

Selection of ovine housekeeping genes for normalisation by real-time RT-PCR; analysis of PrP gene expression and genetic susceptibility to scrapie  

Microsoft Academic Search

BACKGROUND: Cellular prion protein expression is essential for the development of transmissible spongiform encephalopathies (TSEs), and in sheep, genetic susceptibility to scrapie has been associated to PrP gene polymorphisms. To test the hypothetical linkage between PrP gene expression and genetic susceptibility, PrP mRNA levels were measured by real-time RT-PCR in six ovine tissues of animals with different genotypes. RESULTS: Previous

David Garcia-Crespo; Ramón A Juste; Ana Hurtado

2005-01-01

81

Evaluation of Genetic Susceptibility Loci for Obesity in Chinese Women  

PubMed Central

Recent genome-wide association (GWA) studies have identified 18 genetic loci for obesity. Using directly observed and imputed GWA genotyping data on approximately 5,000 Chinese women (1996–2007), the authors evaluated 17 single nucleotide polymorphisms (SNPs) that represent 17 distinct obesity loci. Two SNPs near the BAT2 and MC4R genes and 3 SNPs within the FTO, SEC16B, and SH2B1 genes were significantly associated with body mass index (weight (kg)/height (m)2), body weight, and the prevalence of obesity. The per-allele increase in body mass index ranged from 0.16 units (BAT2) to 0.38 units (SH2B1). Odds ratios for obesity ranged from 1.46 (95% confidence interval (CI): 1.12, 1.92) for BAT2 to 2.16 (95% CI: 1.39, 3.37) for MC4R. A genetic risk score calculated by summing the number of risk-increasing alleles that each woman carried at these 5 loci was significantly associated with the prevalence of obesity. Women carrying 5 or more risk alleles had a 3.13-fold (95% CI: 2.06, 4.77) higher prevalence of obesity than women carrying 1 or no risk alleles. Results from this study extend some previous GWA findings to Chinese women and show the need for additional studies to identify susceptibility loci in Chinese and other Asian populations.

Shi, Jiajun; Long, Jirong; Gao, Yu-Tang; Lu, Wei; Cai, Qiuyin; Wen, Wanqing; Zheng, Ying; Yu, Kai; Xiang, Yong-Bing; Zheng, Wei; Shu, Xiao-Ou

2010-01-01

82

The genetics of complex autoimmune diseases: non-MHC susceptibility genes  

Microsoft Academic Search

Susceptibility to complex autoimmune diseases (AIDs) is a multigenic phenotype affected by a variety of genetic and environmental or stochastic factors. After over a decade of linkage analyses, the identification of non-major histocompatibility complex (non-MHC) susceptibility alleles has proved to be difficult, predominantly because of extensive genetic heterogeneity and possible epistatic interactions among the multiple genes required for disease development.

Amy Wanstrat; Edward Wakeland

2001-01-01

83

Genetic susceptibility to non-polyposis colorectal cancer  

PubMed Central

Familial colorectal cancer (CRC) is a major public health problem by virtue of its relatively high frequency. Some 15-20% of all CRCs are familial. Among these, familial adenomatous polyposis (FAP), caused by germline mutations in the APC gene, accounts for less than 1%. Hereditary non-polyposis colorectal cancer (HNPCC), also called Lynch syndrome, accounts for approximately 5-8% of all CRC patients. Among these, some 3% are mutation positive, that is, caused by germline mutations in the DNA mismatch repair genes that have so far been implicated (MLH1, MSH2, MSH6, PMS1, and PMS2). Most of the remaining patients belonging to HNPCC or HNPCC-like families are still molecularly unexplained. Among the remaining familial CRCs, a large proportion is probably caused by gene mutations and polymorphisms of low penetrance, of which the I1307K polymorphism in the APC gene is a prime example.?Molecular genetic findings have enabled hereditary CRC to be divided into two groups: (1) tumours that show microsatellite instability (MSI), occur more frequently in the right colon, have diploid DNA, harbour characteristic mutations such as transforming growth factor ? type II receptor and BAX, and behave indolently, of which HNPCC is an example; and (2) tumours with chromosomal instability (CIN), which tend to be left sided, show aneuploid DNA, harbour characteristic mutations such as K-ras, APC, and p53, and behave aggressively, of which FAP is an example.?This review focuses most heavily on the clinical features, pathology, molecular genetics, surveillance, and management including prophylactic surgery in HNPCC. Because of the difficulty in diagnosing HNPCC, a detailed differential diagnosis of the several hereditary CRC variants is provided. The extant genetic and phenotypic heterogeneity in CRC leads to the conclusion that it is no longer appropriate to discuss the genetics of CRC without defining the specific hereditary CRC syndrome of concern. Therefore, it is important to ascertain cancer of all anatomical sites, as well as non-cancer phenotypic stigmata (such as the perioral and mucosal pigmentations in Peutz-Jeghers syndrome), when taking a family cancer history.???Keywords: colorectal cancer; hereditary non-polyposis colorectal cancer; genetic susceptibility

Lynch, H.; de la Chapelle, A.

1999-01-01

84

Autism genetic database (AGD): a comprehensive database including autism susceptibility gene-CNVs integrated with known noncoding RNAs and fragile sites  

Microsoft Academic Search

BACKGROUND: Autism is a highly heritable complex neurodevelopmental disorder, therefore identifying its genetic basis has been challenging. To date, numerous susceptibility genes and chromosomal abnormalities have been reported in association with autism, but most discoveries either fail to be replicated or account for a small effect. Thus, in most cases the underlying causative genetic mechanisms are not fully understood. In

Gregory Matuszek; Zohreh Talebizadeh

2009-01-01

85

Genetic and environmental determinants of the susceptibility of Amerindian derived populations for having hypertriglyceridemia.  

PubMed

Here, we discuss potential explanations for the higher prevalence of hypertriglyceridemia in populations with an Amerindian background. Although environmental factors are the triggers, the search for the ethnic related factors that explain the increased susceptibility of the Amerindians is a promising area for research. The study of the genetics of hypertriglyceridemia in Hispanic populations faces several challenges. Ethnicity could be a major confounding variable to prove genetic associations. Despite that, the study of hypertriglyceridemia in Hispanics has resulted in significant contributions. Two GWAS reports have exclusively included Mexican mestizos. Fifty percent of the associations reported in Caucasians could be generalized to the Mexicans, but in many cases the Mexican lead SNP was different than that reported in Europeans. Both reports included new associations with apo B or triglycerides concentrations. The frequency of susceptibility alleles in Mexicans is higher than that found in Europeans for several of the genes with the greatest effect on triglycerides levels. An example is the SNP rs964184 in APOA5. The same trend was observed for ANGPTL3 and TIMD4 variants. In summary, we postulate that the study of the genetic determinants of hypertriglyceridemia in Amerindian populations which have major changes in their lifestyle, may prove to be a great resource to identify new genes and pathways associated with hypertriglyceridemia. PMID:24768220

Aguilar-Salinas, Carlos A; Tusie-Luna, Teresa; Pajukanta, Päivi

2014-07-01

86

Genetic background of diabetic and nondiabetic sibs in young Bangladeshis.  

PubMed

The prevalence of diabetes mellitus in the young is higher in Bangladesh like other Asian developing nations. Albeit, undernutrition has been shown to be associated with diabetes in the young, not all such individuals are diabetic. Diabetes Mellitus is a multigenic disease. In IDDM, DR3/4 heterozygotes were shown to have a greatly increased risk of developing the disease, suggesting the concept of genetic factor(s) being involved in the development of diabetes. Therefore, this study was undertaken to determine the distribution of HLA class II alleles (DRB) and to identify the HLA associated risk for developing diabetes mellitus in the young Bangladeshis. A total of fifty individuals were investigated. Half of them (n=25) were diabetic patients, registered in BIRDEM and half the participants were their non-diabetic sibs. A genomic DNA PCR and Enzyme Linked Probe Hybridization Assay (ELPHA, Bio-test, Germany) was used to determine HLA class II alleles (DRB1, DRB 3, 4, 5) by in vitro amplification of DRB gene. Among all the sero-equivalent antigens found in the study subjects, the prevalence of DR15 (DR2) was overrepresented, both in the diabetic subjects and in their non-diabetic sibs. Moreover, compared with the non-diabetic group the diabetic patients showed higher frequency of DR15 alleles (39 and 25%) though the difference was not significant (chisq. 1.7, p>0.05). Next to DR15, DR4 was the most prevalent HLA-DRB gene found in the study population. Interestingly, the frequency of DR4 was higher in the diabetic than in the non-diabetic group (20 vs. 14%). The study showed that the DR15 and DR4 were the most prevalent in the study population. Moreover, DR7 though not very significant, was higher in non-diabetic compared to their diabetic sibs. Comparison between the diabetic and non-diabetic sibs could have been interesting and significant but we could not confirm our findings, possibly, due to small sample size. A study in a larger paired sample of unrelated population is also needed to substantiate our findings, and also to prove the susceptibility or resistant haplotype in the young diabetic subjects. PMID:11766001

Sayeed, M A; Hassan, M S; Hasan, K N; Parvez, M A; Khan, A Y; Salimullah, M; Khanam, P A; Mahtab, H; Khan, A K

2000-12-01

87

Genetic Background Affects Properties of Satellite Cells and mdx Phenotypes  

PubMed Central

Duchenne muscular dystrophy (DMD) is the most common lethal genetic disorder of children. The mdx (C57BL/10 background, C57BL/10-mdx) mouse is a widely used model of DMD, but the histopathological hallmarks of DMD, such as the smaller number of myofibers, accumulation of fat and fibrosis, and insufficient regeneration of myofibers, are not observed in adult C57BL/10-mdx except for in the diaphragm. In this study, we showed that DBA/2 mice exhibited decreased muscle weight, as well as lower myofiber numbers after repeated degeneration–regeneration cycles. Furthermore, the self-renewal efficiency of satellite cells of DBA/2 is lower than that of C57BL/6. Therefore, we produced a DBA/2-mdx strain by crossing DBA/2 and C57BL/10-mdx. The hind limb muscles of DBA/2-mdx mice exhibited lower muscle weight, fewer myofibers, and increased fat and fibrosis, in comparison with C57BL/10-mdx. Moreover, remarkable muscle weakness was observed in DBA/2-mdx. These results indicate that the DBA/2-mdx mouse is a more suitable model for DMD studies, and the efficient satellite cell self-renewal ability of C57BL/10-mdx might explain the difference in pathologies between humans and mice.

Fukada, So-ichiro; Morikawa, Daisuke; Yamamoto, Yukiko; Yoshida, Tokuyuki; Sumie, Noriaki; Yamaguchi, Masahiko; Ito, Takahito; Miyagoe-Suzuki, Yuko; Takeda, Shin'ichi; Tsujikawa, Kazutake; Yamamoto, Hiroshi

2010-01-01

88

Genetic Structure IDDM1: Two Separate Regions Major Histocompatibility Complex Contribute Susceptibility Protection Genetic Structure IDDM1: Two Separate Regions Major Histocompatibility Complex Contribute Susceptibility Protection P Hanifi McAdam  

EPA Pesticide Factsheets

Did you mean: Genetic Structure IDDM1: Two Separate Regions Major Histocompatibility Complex Contribute Susceptibility Protection Genetic Structure IDDM1: Two Separate Regions Major Histocompatibility Complex Contribute Susceptibility Protection P Hanifi McAdam ?

89

Ethnic Background and Genetic Variation in the Evaluation of Cancer Risk: A Systematic Review  

PubMed Central

The clinical use of genetic variation in the evaluation of cancer risk is expanding, and thus understanding how determinants of cancer susceptibility identified in one population can be applied to another is of growing importance. However there is considerable debate on the relevance of ethnic background in clinical genetics, reflecting both the significance and complexity of genetic heritage. We address this via a systematic review of reported associations with cancer risk for 82 markers in 68 studies across six different cancer types, comparing association results between ethnic groups and examining linkage disequilibrium between risk alleles and nearby genetic loci. We find that the relevance of ethnic background depends on the question. If asked whether the association of variants with disease risk is conserved across ethnic boundaries, we find that the answer is yes, the majority of markers show insignificant variability in association with cancer risk across ethnic groups. However if the question is whether a significant association between a variant and cancer risk is likely to reproduce, the answer is no, most markers do not validate in an ethnic group other than the discovery cohort’s ancestry. This lack of reproducibility is not attributable to studies being inadequately populated due to low allele frequency in other ethnic groups. Instead, differences in local genomic structure between ethnic groups are associated with the strength of association with cancer risk and therefore confound interpretation of the implied physiologic association tracked by the disease allele. This suggest that a biological association for cancer risk alleles may be broadly consistent across ethnic boundaries, but reproduction of a clinical study in another ethnic group is uncommon, in part due to confounding genomic architecture. As clinical studies are increasingly performed globally this has important implications for how cancer risk stratifiers should be studied and employed.

Jing, Lijun; Su, Li; Ring, Brian Z.

2014-01-01

90

Susceptibility genetic variants associated with early-onset colorectal cancer.  

PubMed

Colorectal cancer (CRC) is the second most common cancer in Western countries. Hereditary forms only correspond to 5% of CRC burden. Recently, genome-wide association studies have identified common low-penetrant CRC genetic susceptibility loci. Early-onset CRC (CRC<50 years old) is especially suggestive of hereditary predisposition although 85-90% of heritability still remains unidentified. CRC<50 patients (n = 191) were compared with a late-onset CRC group (CRC>65 years old) (n = 1264). CRC susceptibility variants at 8q23.3 (rs16892766), 8q24.21 (rs6983267), 10p14 (rs10795668), 11q23.1 (rs3802842), 15q13.3 (rs4779584), 18q21 (rs4939827), 14q22.2 (rs4444235), 16q22.1 (rs9929218), 19q13.1 (rs10411210) and 20p12.3 (rs961253) were genotyped in all DNA samples. A genotype-phenotype correlation with clinical and pathological characteristics in both groups was performed. Risk allele carriers for rs3802842 [Odds ratio (OR) = 1.5, 95% confidence interval (CI) 1.1-2.05, P = 0.0096, dominant model) and rs4779584 (OR = 1.39, 95% CI 1.02-1.9, P = 0.0396, dominant model) were more frequent in the CRC<50 group, whereas homozygotes for rs10795668 risk allele were also more frequent in the early-onset CRC (P = 0.02, codominant model). Regarding early-onset cases, 14q22 (rs4444235), 11q23 (rs3802842) and 20p12 (rs961253) variants were more associated with family history of CRC or tumors of the Lynch syndrome spectrum excluding CRC. In our entire cohort, sum of risk alleles was significantly higher in patients with a CRC family history (OR = 1.40, 95% CI 1.06-1.85, P = 0.01). In conclusion, variants at 10p14 (rs10795668), 11q23.1 (rs3802842) and 15q13.3 (rs4779584) may have a predominant role in predisposition to early-onset CRC. Association of CRC susceptibility variants with some patient's familiar and personal features could be relevant for screening and surveillance strategies in this high-risk group and it should be explored in further studies. PMID:22235025

Giráldez, María Dolores; López-Dóriga, Adriana; Bujanda, Luis; Abulí, Anna; Bessa, Xavier; Fernández-Rozadilla, Ceres; Muñoz, Jenifer; Cuatrecasas, Miriam; Jover, Rodrigo; Xicola, Rosa M; Llor, Xavier; Piqué, Josep M; Carracedo, Angel; Ruiz-Ponte, Clara; Cosme, Angel; Enríquez-Navascués, José María; Moreno, Victor; Andreu, Montserrat; Castells, Antoni; Balaguer, Francesc; Castellví-Bel, Sergi

2012-03-01

91

Removing Background Phase Variations in Susceptibility Weighted Imaging Using a Fast, Forward-Field Calculation  

PubMed Central

Purpose To estimate magnetic field variations induced from air-tissue interface geometry and remove their effects from susceptibility weighted imaging (SWI) data. Materials and Methods A Fourier-transform-based field estimation method is used to calculate the field deviation arising from air-tissue interface geometry. This is accomplished by, first, manually drawing or automatically detecting the sinuses, the mastoid cavity and the head geometry. The difference in susceptibility, ??, between brain tissue and air-spaces is then calculated using a residual-phase minimization approach. SWI data are corrected by subtracting the predicted phase from the original phase image. Resultant phase images are then used to perform the SWI post-processing. Results Significant improvement in the post-processed SWI data is demonstrated, most notably in the frontal and midbrain regions and to a lesser extent at the boundary of the brain. Specifically, there is much less dropout of signal after phase correction near air-tissue interfaces making it possible to see vessels and structures that were often incorrectly removed by the conventional SWI post-processing. Conclusion The Fourier-transform-based field estimation method is a powerful 3D background phase removal method for improving SW images, providing clearer images of the fore-brain and the mid-brain regions.

Neelavalli, Jaladhar; Cheng, Yu-Chung N.; Jiang, Jing; Haacke, E. Mark

2009-01-01

92

Non-obese diabetic (NOD) mice are genetically susceptible to experimental autoimmune prostatitis (EAP).  

PubMed

Rodents develop inflammatory, non-infectious, prostatitis upon autoimmuniz-ation with male accessory gland (MAG) extracts in complete Freund's adjuvant (CFA). Although there appears to be differences among strains, with respect to susceptibility to induction, specific details are not known about the genetic bases of such differences. Because NOD mice have inherited a genetic predisposition to autoimmune lesions affecting, apart from the islets of Langerhans, a large array of secretory glands such as salivary glands, thyroid, parathyroids and adrenal cortex, we selected this strain to assess the influence of inherited genes upon experimentally-induced autoimmune prostatitis (EAP). Indeed, MAG extracts injected into young NOD males in association with CFA cause a severe inflammatory reaction in the prostate, accompanied by a humoral and T cell-mediated response. NOD mice develop a more aggressive form of EAP than Wistar rats, the strain of reference used to establish the model. In NOD mice, disease begins earlier, affects 100% of the animals, does not require boosting and leads to florid infiltrates circumscribed to lateral and dorsal prostatic lobes. Immune mice develop a T cell-mediated response to MAG assessed by in vitro proliferation and accompanied by the release of IFN-gamma, whereas IL-4 is not detectable in the same culture super-natants. To assess the influence of the NOD background genes upon EAP susceptibility, we tested C57BL/6.H2(g7) mice in parallel. NOD mice are considerably more susceptible to EAP induction than congenic C57BL/6.H2(g7) mice. Both strains demonstrate a detectable humoral and cell-mediated response against MAG, but the histopathological manifestations are considerably more dramatic in NOD than in the C57BL/6.H2(g7) strain. Our results thus support the notion that NOD mice have background genes which favour severe autoimmune manifestations, irrespective of the target tissue. PMID:9878082

Rivero, V E; Cailleau, C; Depiante-Depaoli, M; Riera, C M; Carnaud, C

1998-12-01

93

Natural genetic variation determines susceptibility to aggregation or toxicity in a C. elegans model for polyglutamine disease  

PubMed Central

Background Monogenic gain-of-function protein aggregation diseases, including Huntington’s disease, exhibit substantial variability in age of onset, penetrance, and clinical symptoms, even between individuals with similar or identical mutations. This difference in phenotypic expression of proteotoxic mutations is proposed to be due, at least in part, to the variability in genetic background. To address this, we examined the role of natural variation in defining the susceptibility of genetically diverse individuals to protein aggregation and toxicity, using the Caenorhabditis elegans polyglutamine model. Results Introgression of polyQ40 into three wild genetic backgrounds uncovered wide variation in onset of aggregation and corresponding toxicity, as well as alteration in the cell-specific susceptibility to aggregation. To further dissect these relationships, we established a panel of 21 recombinant inbred lines that showed a broad range of aggregation phenotypes, independent of differences in expression levels. We found that aggregation is a transgressive trait, and does not always correlate with measures of toxicity, such as early onset of muscle dysfunction, egg-laying deficits, or reduced lifespan. Moreover, distinct measures of proteotoxicity were independently modified by the genetic background. Conclusions Resistance to protein aggregation and the ability to restrict its associated cellular dysfunction are independently controlled by the natural variation in genetic background, revealing important new considerations in the search for targets for therapeutic intervention in conformational diseases. Thus, our C. elegans model can serve as a powerful tool to dissect the contribution of natural variation to individual susceptibility to proteotoxicity. Please see related commentary by Kaeberlein, http://www.biomedcentral.com/1741-7007/11/102.

2013-01-01

94

Does your gene need a background check? How genetic background impacts the analysis of mutations, genes, and evolution  

PubMed Central

The premise of genetic analysis is that a causal link exists between phenotypic and allelic variation. Yet it has long been documented that mutant phenotypes are not a simple result of a single DNA lesion, but rather are due to interactions of the focal allele with other genes and the environment. Although an experimentally rigorous approach focused on individual mutations and isogenic control strains has facilitated amazing progress within genetics and related fields, a glimpse back suggests that a vast complexity has been omitted from our current understanding of allelic effects. Armed with traditional genetic analyses and the foundational knowledge they have provided, we argue that the time and tools are ripe to return to the under-explored aspects of gene function and embrace the context-dependent nature of genetic effects. We assert that a broad understanding of genetic effects and the evolutionary dynamics of alleles requires identifying how mutational outcomes depend upon the “wild-type” genetic background. Furthermore, we discuss how best to exploit genetic background effects to broaden genetic research programs.

Chandler, Christopher H.; Chari, Sudarshan; Dworkin, Ian

2013-01-01

95

Identifying Predictors of Activity Based Anorexia Susceptibility in Diverse Genetic Rodent Populations  

PubMed Central

Animal studies are very useful in detection of early disease indicators and in unravelling the pathophysiological processes underlying core psychiatric disorder phenotypes. Early indicators are critical for preventive and efficient treatment of progressive psychiatric disorders like anorexia nervosa. Comparable to physical hyperactivity observed in anorexia nervosa patients, in the activity-based anorexia rodent model, mice and rats express paradoxical high voluntary wheel running activity levels when food restricted. Eleven inbred mouse strains and outbred Wistar WU rats were exposed to the activity-based anorexia model in search of identifying susceptibility predictors. Body weight, food intake and wheel running activity levels of each individual mouse and rat were measured. Mouse strains and rats with high wheel running activity levels during food restriction exhibited accelerated body weight loss. Linear mixed models for repeated measures analysis showed that baseline wheel running activity levels preceding the scheduled food restriction phase strongly predicted activity-based anorexia susceptibility (mice: Beta ?=? ?0.0158 (±0.003 SE), P<0.0001; rats: Beta ?=? ?0.0242 (±0.004 SE), P<0.0001) compared to other baseline parameters. These results suggest that physical activity levels play an important role in activity-based anorexia susceptibility in different rodent species with genetically diverse background. These findings support previous retrospective studies on physical activity levels in anorexia nervosa patients and indicate that pre-morbid physical activity levels could reflect an early indicator for disease severity.

Pjetri, Eneda; de Haas, Ria; de Jong, Simone; Gelegen, Cigdem; Oppelaar, Hugo; Verhagen, Linda A. W.; Eijkemans, Marinus J. C.; Adan, Roger A.; Olivier, Berend; Kas, Martien J.

2012-01-01

96

Genetic Variants Modify Susceptibility to Leukemia in Infants: A Children's Oncology Group Report  

PubMed Central

Background The mixed lineage leukemia (MLL) gene is commonly rearranged in infant leukemia (IL). Genetic determinants of susceptibility to IL are unknown. Recent genome wide association studies for childhood acute lymphoblastic leukemia (ALL) have identified susceptibility loci at IKZF1, ARID5B, and CEBPE. Procedure We genotyped these loci in 171 infants with leukemia and 384 controls and evaluated associations overall, by subtype (ALL, acute myeloid leukemia (AML)), and by presence (+) or absence (?) of MLL rearrangements. Results Homozygosity for a variant IKZF1 allele (rs11978267) increased risk of infant AML (Odds Ratio (OR)=3.9, 95% Confidence Interval (CI)=1.8–8.4); the increased risk was similar for AML/MLL+ and MLL? cases. In contrast, risk of ALL/MLL? was increased in infants homozygous for the IKZF1 variant (OR=5.1, 95%CI=1.8–14.5) but the variant did not modify risk of ALL/MLL+. For ARID5B (rs10821936), homozygosity for the variant allele increased risk for the ALL/MLL? subgroup only (OR=7.2, 95%CI=2.5–20.6). There was little evidence of an association with the CEBP variant (rs2239633). Conclusion IKZF1 is expressed in early hematopoiesis, including precursor myeloid cells. Our data provide the first evidence that IKZF1 modifies susceptibility to infant AML, irrespective of MLL rearrangements, and could provide important new etiologic insights into this rare and heterogeneous hematopoietic malignancy.

Ross, Julie A.; Linabery, Amy M.; Blommer, Crystal N.; Langer, Erica K.; Spector, Logan G.; Hilden, Joanne M.; Heerema, Nyla A.; Radloff, Gretchen A.; Tower, Richard L.; Davies, Stella M.

2012-01-01

97

Transfer of the Rf-1 region from FHH onto the ACI background increases susceptibility to renal impairment.  

PubMed

The genetically hypertensive fawn-hooded (FHH/Eur) rat is characterized by the early presence of systolic and glomerular hypertension, progressive proteinuria (UPV), and albuminuria (UAV), and focal glomerulosclerosis, resulting in premature death from renal failure. Previous studies showed that at least five genetic loci (Rf-1 to Rf-5) were linked to the development of renal impairment. Of these five, Rf-1 appears to play a major role. To study the impact of Rf-1 in the absence of the other loci, we transferred the Rf-1 region of chromosome 1, between the markers D1Mit34 and D1Rat156, Rf-1B for short, onto the genomic background of the normotensive August x Copenhagen Irish (ACI) rat. In this congenic strain, named ACI.FHH-D1Mit34/Rat156 or ACI.FHH-Rf1B, we challenged the renal hemodynamic function of these animals by studying the effects of unilateral nephrectomy (UNX) alone, or combined with N(G)-nitro-L-arginine methyl ester (L-NAME)-induced hypertension. Following UNX, the congenic strain developed significantly more UPV and UAV than the ACI progenitor. The differences were even more pronounced when UNX was combined with an L-NAME-induced rise in systolic blood pressure to about 150 mmHg, i.e., the level of hypertension present in the parental FHH strain. These findings indicate that the Rf-1B region of the FHH rat contains at least one gene affecting the susceptibility to progressive renal failure, especially in the presence of an increase in blood pressure. PMID:11875190

Provoost, Abraham P; Shiozawa, Masahide; Van Dokkum, Richard P E; Jacob, Howard J

2002-02-28

98

Genetic susceptibility of the donor kidney contributes to the development of renal damage after syngeneic transplantation  

Microsoft Academic Search

Solitary kidneys, especially in rats, appear vulnerable to develop functional and structural damage. However, differences in susceptibility exist between strains. It is not clear whether this is intrinsic to the kidney or due to environmental factors. Therefore, the aim of the present study was to investigate possible differences in genetic susceptibility for renal damage. By transplanting different rat donor kidneys

E. A. Kouwenhoven; R. P. E. van Dokkum; R. L. Marquet; U. W. Heemann; R. W. F. de Bruin; J. N. M. IJzermans; A. P. Provoost

1999-01-01

99

CTLA4 Alanine17 Confers Genetic Susceptibility to Graves' Disease and to Type 1 Diabetes Mellitus  

Microsoft Academic Search

The genetic susceptibility to Graves' disease and type 1 (insulin- dependent) diabetes mellitus is conferred by genes in the human leukocyte antigen region on the short arm of chromosome 6, but several other genes are presumed to determine disease susceptibility. Among those candidate genes is the cytotoxic T lymphocyte antigen 4 (CTLA4) located on chromosome 2q33 in man. We investigated

HORST DONNER; HARALD RAU; PAUL G. WALFISH; JENS BRAUN; THORSTEN SIEGMUND; REINHARD FINKE; JURGEN HERWIG; KLAUS H. USADEL; KLAUS BADENHOOP

100

Genetic Architecture of Susceptibility to PCB126-Induced Developmental Cardiotoxicity in Zebrafish  

PubMed Central

Variability in risk of developmental defects caused by dioxin-like compounds (DLCs) has been demonstrated within and among several vertebrate species. Beyond our knowledge of the aryl hydrocarbon receptor (AHR) and its role in mediating toxicity for this class of compounds, little else is known concerning precise downstream targets influencing this vulnerability. In the present study, zebrafish with divergent genetic backgrounds were screened for susceptibility to developmental cardiotoxicity caused by the prototypical DLC, 3,3?,4,4?,5-pentachlorobiphenyl (PCB126); a range up to ?40-fold differences was observed. Differentially sensitive zebrafish were chosen for a genetic cross, and the recombinant generation was used for genome-wide quantitative trait loci (QTL) mapping. Multiple QTLs were identified––several acting alone, one additively, and two others via epistatic interaction. Together, these QTLs account for 24% of the phenotypic variance observed in cardioteratogenicity resulting from PCB126 exposure (logarithm of the odds = 13.55, p = 1.89 × 10?10). Candidate genes in these QTL regions include the following: ahr2, bcor, and capn1 (Chr 22); e2f1 and pdyn (Chr 23); ctnnt2, plcg1, eno3, tgm1, and tgm2 (interacting on Chr 23); and vezf1 (Chr 15). These data demonstrate that DLC-induced cardiac teratogenicity is a multifactorial complex trait influenced by gene × gene and gene × environment interactions. The identified QTLs harbor many DLC-responsive genes critical to cardiovascular development and provide insight into the genetic basis of susceptibility to AHR-mediated developmental toxicity.

Waits, Eric R.; Nebert, Daniel W.

2011-01-01

101

Impact of genetic background on placental glycogen storage in mice.  

PubMed

129 and C57BL/6 are two of the most widely used laboratory mouse strains. While it is well known that genetic modifiers between the two strains can directly influence embryonic and adult phenotypes, less is known regarding morphological differences in placental development. Here we identify differences in the junctional zone, glycogen storage and the maternal-fetal interface between these two strains and provide examples where these differences impact the phenotypic characterisation of placental mutations. PMID:22153913

Tunster, S J; Van de Pette, M; John, R M

2012-02-01

102

Genetic background of tolerance breakdown in rheumatoid arthritis.  

PubMed

Rheumatoid arthritis (RA) is a complex mutifactorial autoimmune disease. As anti-citrullinated peptide antibodies (ACPA) exhibit unique specificity for RA, breakdown of immunological tolerance to citrullinated self-proteins is considered to be a key feature of RA pathogenesis. While environmental factors such as smoking and viral infections have been implicated in the pathogenesis, recent genome-scans for RA have unraveled multiple genetic factors involved in RA. Some of these genetic factors may specifically contribute to the tolerance breakdown of RA. For instance, PADI4 gene encoding an enzyme that converts arginine residues to citrullines may enhance the production of auto-antigens. These citrullinated proteins are then presented to helper T-cells via HL-DR molecule on the antigen presenting cells, where specific HLA-DRB1 alleles encoding "shared-epitope" have significant relevance to RA. On the other hand, genes regulating the activity of lymphocytes such as PTPN22 and FCRL3 may influence auto-reactivity of individual lymphocytes. Taken together, combination of these genetic factors accelerates autoimmune response in RA. PMID:20453439

Kochi, Yuta

2010-01-01

103

T Helper Phenotype and Genetic Susceptibility in Experimental Lyme Disease  

Microsoft Academic Search

Summary Infection of inbred mice with Borrelia burgdorferi results in strain-specific variation in the severity of pathogen-induced arthritis: BALB\\/c mice develop only mild disease whereas C3H\\/HeJ mice develop severe arthritis. The immunologic basis for varying host susceptibility has yet to be defined. We modified experimental Lyme disease to facilitate measurement of antigen-specific cytokine production in resistant and susceptible mice. The

Jennifer E. Matyniak; Steven L. Reiner

104

Host genetic background impacts modulation of the TLR4 pathway by RON in tissue-associated macrophages  

PubMed Central

Toll-like receptors (TLRs) enable metazoans to mount effective innate immune responses to microbial and viral pathogens, as well as to endogenous host-derived ligands. It is understood that genetic background of the host can influence TLR responsiveness, altering susceptibility to pathogen infection, autoimmunity and cancer. Macrophage stimulatory protein (MSP), which activates the receptor tyrosine kinase recepteur d'origine nantais (RON), promotes key macrophage functions such as motility and phagocytic activity. MSP also acts via RON to modulate signaling by TLR4, which recognizes a range of pathogen or endogenous host-derived molecules. Here, we show that RON exerts divergent control over TLR4 activity in macrophages from different mouse genetic backgrounds. RON potently modulated the TLR4 response in macrophages from M2-prone FVB mice, as compared with M1-skewed C57Bl6 mice. Moreover, global expression analysis revealed that RON suppresses the TLR4-dependent type-I interferon gene signature only in FVB macrophages. This leads to attenuated production of the potent inflammatory mediator, tumor necrosis factor-?. Eliminating RON kinase activity markedly decreased carcinogen-mediated tumorigenesis in M2/Th2-biased FVB mice. We propose that host genetic background influences RON function, thereby contributing to the variability in TLR4 responsiveness in rodents and, potentially, in humans. These findings provide novel insight into the complex interplay between genetic context and immune function.

Chaudhuri, Amitabha; Wilson, Nicholas S; Yang, Becky; Paler Martinez, Andres; Liu, Jinfeng; Zhu, Catherine; Bricker, Nicole; Couto, Suzana; Modrusan, Zora; French, Dorothy; Cupp, James; Ashkenazi, Avi

2013-01-01

105

The BOADICEA model of genetic susceptibility to breast and ovarian cancer: updating, validation and predictions  

Cancer.gov

The BOADICEA model of genetic susceptibility to breast and ovarian cancer: updating, validation and predictions. Antonis C. Antoniou (1), Paul D.P Pharoah (2) and Douglas F Easton (1) on behalf of the Boadicea collaborators. (1) CR-UK Genetic Epidemiology

106

Antimicrobial susceptibility/resistance and genetic characteristics of Neisseria gonorrhoeae isolates from Poland, 2010-2012  

PubMed Central

Background In Poland, gonorrhoea has been a mandatorily reported infection since 1948, however, the reported incidences are likely underestimated. No antimicrobial resistance (AMR) data for Neisseria gonorrhoeae has been internationally reported in nearly four decades, and data concerning genetic characteristics of N. gonorrhoeae are totally lacking. The aims of this study were to investigate the AMR to previously and currently recommended gonorrhoea treatment options, the main genetic resistance determinant (penA) for extended-spectrum cephalosporins (ESCs), and genotypic distribution of N. gonorrhoeae isolates in Poland in 2010-2012. Methods N. gonorrhoeae isolates cultured in 2010 (n?=?28), 2011 (n?=?92) and 2012 (n?=?108) in Warsaw and Bialystok, Poland, were examined using antimicrobial susceptibility testing (Etest), pyrosequencing of penA and N. gonorrhoeae multi-antigen sequence typing (NG-MAST). Results The proportions of N. gonorrhoeae isolates showing resistance were as follows: ciprofloxacin 61%, tetracycline 43%, penicillin G 22%, and azithromycin 8.8%. No isolates resistant to ceftriaxone, cefixime or spectinomycin were found. However, the proportion of isolates with an ESC MIC?=?0.125 mg/L, i.e. at the resistance breakpoint, increased significantly from none in 2010 to 9.3% and 19% in 2012 for ceftriaxone and cefixime, respectively. Furthermore, 3.1% of the isolates showed multidrug resistance, i.e., resistance to ciprofloxacin, penicillin G, azithromycin, and decreased susceptibility to cefixime (MIC?=?0.125 mg/L). Seventy-six isolates (33%) possessed a penA mosaic allele and 14 isolates (6.1%) contained an A501V/T alteration in penicillin-binding protein 2. NG-MAST ST1407 (n?=?58, 25% of isolates) was the most prevalent ST, which significantly increased from 2010 (n?=?0) to 2012 (n?=?46; 43%). Conclusions In Poland, the diversified gonococcal population displayed a high resistance to most antimicrobials internationally previously recommended for gonorrhoea treatment and decreasing susceptibility to the currently recommended ESCs. The decreasing susceptibility to ESCs was mostly due to the introduction of the internationally spread multidrug-resistant NG-MAST ST1407 in 2011. It is essential to promptly revise the gonorrhoea treatment guidelines, improve the gonorrhoea laboratory diagnostics, and implement quality assured surveillance of gonococcal AMR (ideally also treatment failures) in Poland.

2014-01-01

107

Is Genetic Background Important in Lung Cancer Survival?  

Microsoft Academic Search

BackgroundIn lung cancer, a patient's survival is poor with a wide variation in survival within the stage of disease. The aim of this study was to investigate the familial concordance in lung cancer survival by means of analyses of pairs with different degrees of familial relationships.MethodsOur population-based Swedish family database included three million families and over 58 100 lung cancer

Linda S. Lindström; Per Hall; Mikael Hartman; Fredrik Wiklund; Kamila Czene; Amanda Ewart Toland

2009-01-01

108

A new genetic assay for rifampicin susceptibility of Mycobacterium tuberculosis.  

PubMed

A new method for testing rifampicin (RFP) susceptibility of Mycobacterium tuberculosis was developed. This method is based on detection of the internal sequence derived from 71-kDa heat shock protein mRNA in tubercle bacilli heat-treated in the presence of RFP. The target sequence was amplified by reverse transcription and PCR, followed by agarose gel electrophoretic analysis. No amplification occurred in one RFP-susceptible strain by exposure to 45 degrees C for 45 min in Middlebrook 7H9 broth containing RFP (10 micrograms/ml) after overnight incubation at 37 degrees C. On the other hand, an amplified 275-bp product was obtained from the RFP-resistant strain MY-129. In a subsequent trial using 65 clinical isolates, this method defined their RFP susceptibility levels as well as the verification of the MICs obtained by the conventional agar dilution method, with the exception of one RFP-susceptible strain. Thus, this method provides a rapid and practical system to determine RFP susceptibility in M. tuberculosis. PMID:8586885

Kusunoki, S; Takemura, K; Takagi, K; Inagaki, Y; Asaka, J; Ezaki, T; Igimi, H

1995-12-01

109

Genetic analysis of the susceptibility of mouse cytomegalovirus to acyclovir.  

PubMed Central

Eight independently derived mouse cytomegalovirus (MCMV) mutants resistant to acyclovir (ACV) were obtained by the sequential plating of wild-type virus in increasing concentrations of ACV. Results of complementation studies among these eight mutants suggest that all had mutations within the same or closely associated genes. A ninth MCMV mutant resistant to phosphonoacetate (PAA) derived by plating wild-type virus in the presence of 100 micrograms of PAA per ml displayed coresistance to ACV and was unable to complement any of the ACV-derived mutants. Recombination experiments among all combinations of the nine MCMV mutants were performed and supported the complementation data in that no recombination could be detected. Seven of the eight ACV-resistant mutants demonstrated cross-resistance to PAA and hypersensitivity to aphidicolin. The one mutant not coresistant to PAA was more susceptible to PAA than was the parent virus. Only a few mutants demonstrated coresistance when the mutants were tested against 9-beta-D-arabinofuranosyladenine (ara-A). The ACV mutant that demonstrated increased susceptibility to PAA was 30-fold more susceptible to ara-A but remained unchanged in susceptibility to aphidicolin. Two of the parent-mutant combinations were selected for DNA synthesis analysis in the presence of ACV (5 microM). A significant decrease in DNA synthesis was demonstrated for both parent viruses, and there was little effect on mutant virus DNA synthesis at the same drug concentration. These results suggest that susceptibility of MCMV to ACV is confined to a product of a single gene and that a mutation of this gene can lead to an altered phenotype when compared with parent virus in susceptibility of DNA synthesis to PAA, ara-A, and aphidicolin, drugs that are known to inhibit DNA polymerase activity. Images

Sandford, G R; Wingard, J R; Simons, J W; Staal, S P; Saral, R; Burns, W H

1985-01-01

110

Genetic susceptibility to the respiratory effects of air pollution  

Microsoft Academic Search

There is large variation between individuals in their response to air pollutants. This review summarises the existing evidence that genetic factors influence the mechanisms of lung injury caused by air pollutants. Genetic association studies have compared the adverse effects of air pollutants between subjects with specific genotypes in biologically relevant genes. In human studies of ozone exposure, polymorphisms in oxidative

I A Yang; K M Fong; P V Zimmerman; S T Holgate; J W Holloway

2009-01-01

111

A study to survey susceptible genetic factors responsible for troglitazone-associated hepatotoxicity in Japanese patients with type 2 diabetes mellitus  

Microsoft Academic Search

Background and objective: Troglitazone is a 2,4-thiazolidinedione antidiabetic agent with insulin-sensitizing activities. This agent had been used efficiently in a large number of patients but was withdrawn from the market in March 2000 because of its association with idiosyncratic hepatotoxicity. To address the susceptible genetic factors responsible for the hepatotoxicity associated with this agent, we performed a genetic polymorphic analysis

Ichiro Watanabe; Aiko Tomita; Miho Shimizu; Mie Sugawara; Hiroaki Yasumo; Ryuta Koishi; Tohru Takahashi; Kaoru Miyoshi; Kouichi Nakamura; Takashi Izumi; Yasuyuki Matsushita; Hidehiko Furukawa; Hideyuki Haruyama; Teiichiro Koga

2003-01-01

112

A search for environmental and genetic background for neural tube defects: twenty-five years of experience.  

PubMed

The present paper illustrates the author's 25-year experience in a step by step approach to the definition of environmental and genetic background of neural tube defects. Based on the birth defects registry, a complete ascertainment of all deliveries was performed in Southern Poland during two periods: 1970-1972, and 1979-1981. The birth prevalence of neural tube defects (NTD), as well as other CNS malformations was determined. The empiric recurrence risk was calculated as 3.2% +/- 1.6. Based on this figure, the relative risk (RR = 37.6 p < 0.001) and heritability (h2 = 74.7 +/- 6.7) were estimated. Our own modification of Morton's complex segregation analysis was applied. Three Mendelian (dominant, additive and recessive) and one multifactorial model were tested. The results did not provide a clear cut discrimination between different models; however the lowest x2 value was obtained for additive inheritance with 61% of penetrance and the frequency of sporadic cases equaled 55%. A search for genetic markers did not support the hypothesis that HLA-A,B,C loci are equivalents of T/t like locus in mice. The results of the study on transcobalamine levels in amniotic fluid may suggests that different transcobalamine metabolism reflects phenotypic expression of genetic susceptibility to NTD development. Current research status and future perspectives on genetic and environmental background of NTD are also presented. PMID:9208165

Pietrzyk, J J

1997-06-01

113

Network Launched to Support Studies of Genetic Susceptibility to Cancer  

Cancer.gov

The National Cancer Institute announced today it has awarded cooperative agreements for the new Cancer Genetics Network, a major research initiative to create a national network of centers specializing in the study of inherited predisposition to cancer.

114

Genetic Background Affects Human Glial Fibrillary Acidic Protein Promoter Activity  

PubMed Central

The human glial fibrillary acidic protein (hGFAP) promoter has been used to generate numerous transgenic mouse lines, which has facilitated the analysis of astrocyte function in health and disease. Here, we evaluated the expression levels of various hGFAP transgenes at different ages in the two most commonly used inbred mouse strains, FVB/N (FVB) and C57BL/6N (B6N). In general, transgenic mice maintained on the B6N background displayed weaker transgene expression compared with transgenic FVB mice. Higher level of transgene expression in B6N mice could be regained by crossbreeding to FVB wild type mice. However, the endogenous murine GFAP expression was equivalent in both strains. In addition, we found that endogenous GFAP expression was increased in transgenic mice in comparison to wild type mice. The activities of the hGFAP transgenes were not age-dependently regulated. Our data highlight the importance of proper expression analysis when non-homologous recombination transgenesis is used.

Bai, Xianshu; Saab, Aiman S.; Huang, Wenhui; Hoberg, Isolde K.; Kirchhoff, Frank; Scheller, Anja

2013-01-01

115

Mitochondrial DNA haplogroup confers genetic susceptibility to nasopharyngeal carcinoma in Chaoshanese from Guangdong, China.  

PubMed

Recent studies have shown association of mtDNA background with cancer development. We analyzed mitochondrial DNA (mtDNA) control region variation of 201 patients with nasopharyngeal carcinoma (NPC) and of 201 normal controls from Chaoshan Han Chinese to discern mtDNA haplogroup effect on the disease onset. Binary logistic regression analysis with adjustment for gender and age revealed that the haplogroup R9 (P = 0.011, OR = 1.91, 95% CI = 1.16-3.16), particularly its sub-haplogroup F1 (P = 0.015, OR = 2.43, 95% CI = 1.18-5.00), were associated significantly with increased NPC risk. These haplogroups were further confirmed to confer high NPC risk in males and/or individuals ? 40 years of age, but not in females or in subjects <40 years old. Our results indicated that mtDNA background confers genetic susceptibility to NPC in Chaoshan Han Chinese, and R9, particularly its sub-haplogroup F1, is a risk factor for NPC. PMID:24498198

Hu, Sheng-Ping; Du, Ju-Ping; Li, De-Rui; Yao, Yong-Gang

2014-01-01

116

Mycobacterium avium subsp. paratuberculosis, Genetic Susceptibility to Crohn's Disease, and Sardinians: the Way Ahead  

Microsoft Academic Search

The present study was performed to determine what proportion of people in Sardinia with or without Crohn's disease were infected with Mycobacterium avium subspecies paratuberculosis and had a preponderance of allelic variants of Nod2, an intracellular protein involved in Crohn's disease susceptibility. Genetic analysis of the alleles of the NOD2\\/CARD15 gene (insC3020, G908R, and R702W alleles), linked to susceptibility or

Leonardo A. Sechi; Maria Gazouli; John Ikonomopoulos; John C. Lukas; Antonio M. Scanu; Niyaz Ahmed; Giovanni Fadda; Stefania Zanetti

2005-01-01

117

Targeted Disruption of Mouse EGF Receptor: Effect of Genetic Background on Mutant Phenotype  

Microsoft Academic Search

Gene targeting was used to create a null allele at the epidermal growth factor receptor locus (Egfr). The phenotype was dependent on genetic background. EGFR deficiency on a CF-1 background resulted in peri-implantation death due to degeneration of the inner cell mass. On a 129\\/Sv background, homozygous mutants died at mid-gestation due to placental defects; on a CD-1 background, the

David W. Threadgill; Andrzej A. Dlugosz; Laura A. Hansen; Tamar Tennenbaum; Ulrike Lichti; Della Yee; Christian Lamantia; Tracy Mourton; Karl Herrup; Raymond C. Harris; John A. Barnard; Stuart H. Yuspa; Robert J. Coffey; Terry Magnuson

1995-01-01

118

Genetic diversity and antifungal susceptibility profiles in causative agents of sporotrichosis  

PubMed Central

Background Sporotrichosis is a chronic subcutaneous mycosis of humans and animals, which is typically acquired by traumatic inoculation of plant material contaminated with Sporothrix propagules, or via animals, mainly felines. Sporothrix infections notably occur in outbreaks, with large epidemics currently taking place in southeastern Brazil and northeastern China. Pathogenic species include Sporothrix brasiliensis, Sporothrix schenckii s. str., Sporothrix globosa, and Sporothrix luriei, which exhibit differing geographical distribution, virulence, and resistance to antifungals. The phylogenetically remote species Sporothrix mexicana also shows a mild pathogenic potential. Methods We assessed a genetically diverse panel of 68 strains. Susceptibility profiles of medically important Sporothrix species were evaluated by measuring the MICs and MFCs for amphotericin B (AMB), fluconazole (FLC), itraconazole (ITC), voriconazole (VRC), posaconazole (PCZ), flucytosine (5FC), and caspofungin (CAS). Haplotype networks were constructed to reveal interspecific divergences within clinical Sporothrix species to evaluate genetically deviant isolates. Results ITC and PCZ were moderately effective against S. brasiliensis (MIC90?=?2 and 2 ?g/mL, respectively) and S. schenckii (MIC90?=?4 and 2 ?g/mL, respectively). PCZ also showed low MICs against the rare species S. mexicana. 5FC, CAS, and FLC showed no antifungal activity against any Sporothrix species. The minimum fungicidal concentration ranged from 2 to >16 ?g/mL for AMB against S. brasiliensis and S. schenckii, while the MFC90 was >16 ?g/mL for ITC, VRC, and PCZ. Conclusion Sporothrix species in general showed high degrees of resistance against antifungals. Evaluating a genetically diverse panel of strains revealed evidence of multidrug resistant phenotypes, underlining the need for molecular identification of etiologic agents to predict therapeutic outcome.

2014-01-01

119

Food makes you a target: disentangling genetic, physiological, and behavioral effects determining susceptibility to infection.  

PubMed

Genetics, physiology, and behavior are all expected to influence the susceptibility of hosts to parasites. Furthermore, interactions between genetic and other factors are suggested to contribute to the maintenance of genetic polymorphism in resistance when the relative susceptibility of host genotypes is context dependent. We used a maternal sibship design and long- and short-term food deprivation treatments to test the role of family-level genetic variation, body condition, physiological state, and foraging behavior on the susceptibility of Lymnaea stagnalis snails to infection by a trematode parasite that uses chemical cues to locate its hosts. In experimental exposures, we found that snails in the long-term food deprivation treatment contracted fewer parasites than snails that were continuously well-fed, possibly because well-fed snails grew larger and attracted more transmission stages. When we kept the long-term feeding rates the same, but manipulated the physiological state and foraging behavior of the snails with short-term food deprivation treatment, we found that snails that were fed before the exposure contracted more parasites than snails that were fed during the exposure. This suggests that direct physiological effects of food processing, but not foraging behavior, predisposed snails to infection. Feeding treatments also affected the family-level variation in snail susceptibility, suggesting that the relative susceptibility of host genotypes was context dependent. PMID:21121912

Seppälä, Otto; Karvonen, Anssi; Haataja, Maarit; Kuosa, Marja; Jokela, Jukka

2011-05-01

120

Genetic context determines susceptibility to intraocular pressure elevation in a mouse pigmentary glaucoma  

PubMed Central

Background DBA/2J (D2) mice develop an age-related form of glaucoma. Their eyes progressively develop iris pigment dispersion and iris atrophy followed by increased intraocular pressure (IOP) and glaucomatous optic nerve damage. Mutant alleles of the Gpnmb and Tyrp1 genes are necessary for the iris disease, but it is unknown whether alleles of other D2 gene(s) are necessary for the distinct later stages of disease. We initiated a study of congenic strains to further define the genetic requirements and disease mechanisms of the D2 glaucoma. Results To further understand D2 glaucoma, we created congenic strains of mice on the C57BL/6J (B6) genetic background. B6 double-congenic mice carrying D2-derived Gpnmb and Tyrp1 mutations develop a D2-like iris disease. B6 single-congenics with only the Gpnmb and Tyrp1 mutations develop milder forms of iris disease. Genetic epistasis experiments introducing a B6 tyrosinase mutation into the congenic strains demonstrated that both the single and double-congenic iris diseases are rescued by interruption of melanin synthesis. Importantly, our experiments analyzing mice at ages up to 27 months indicate that the B6 double-congenic mice are much less prone to IOP elevation and glaucoma than are D2 mice. Conclusion As demonstrated here, the Gpnmb and Tyrp1 iris phenotypes are both individually dependent on tyrosinase function. These results support involvement of abnormal melanosomal events in the diseases caused by each gene. In the context of the inbred D2 mouse strain, the glaucoma phenotype is clearly influenced by more genes than just Gpnmb and Tyrp1. Despite the outward similarity of pigment-dispersing iris disease between D2 and the B6 double-congenic mice, the congenic mice are much less susceptible to developing high IOP and glaucoma. These new congenic strains provide a valuable new resource for further studying the genetic and mechanistic complexity of this form of glaucoma.

Anderson, Michael G; Libby, Richard T; Mao, Mao; Cosma, Ioan M; Wilson, Larry A; Smith, Richard S; John, Simon WM

2006-01-01

121

Gluten ataxia in perspective: epidemiology, genetic susceptibility and clinical characteristics  

Microsoft Academic Search

Summary We previously have described a group of patients with gluten sensitivity presenting with ataxia (gluten ataxia) and suggested that this disease entity may account for a large number of patients with sporadic idiopathic ataxia. We have therefore investigated the prevalence of gluten sensitivity amongst a large cohort of patients with sporadic and familial ataxia and looked at possible genetic

Marios Hadjivassiliou; Richard Grunewald; Basil Sharrack; David Sanders; Alan Lobo; Clare Williamson; Nicola Woodroofe; Nicholas Wood; Aelwyn Davies-Jones

2003-01-01

122

Assessment of genetic susceptibility to ethanol intoxication in mice  

PubMed Central

Increased use of gene manipulation in mice (e.g., targeted or random mutagenesis) has been accompanied by increased reliance on a very few rapid and simple behavioral assays, each of which aspires to model a human behavioral domain. Yet, each assay comprises multiple traits, influenced by multiple genetic factors. Motor incoordination (ataxia), a common characteristic of many neurological disorders, may reflect disordered balance, muscle strength, proprioception, and/or patterned gait. Impaired motor performance can confound interpretation of behavioral assays of learning and memory, exploration, motivation, and sensory competence. The rotarod is one of the most commonly used tests to measure coordination in mice. We show here that exactly how the rotarod test is performed can markedly alter the apparent patterns of genetic influence both in undrugged performance and sensitivity to ethanol intoxication. However, when tested with well chosen parameters, the accelerating rotarod test showed very high inter- and intralaboratory reliability. Depending on test conditions, ethanol can either disrupt or enhance performance in some strains. Genetic contribution to performance on the accelerating versus the fixed-speed rotarod assay can be completely dissociated under some test conditions, and multiple test parameters are needed to assess the range of genetic influence adequately.

Rustay, Nathan R.; Wahlsten, Douglas; Crabbe, John C.

2003-01-01

123

Genetic variation in cytokine-related genes and migraine susceptibility.  

PubMed

Migraine is classified by the World Health Organization (WHO) as being one of the top 20 most debilitating diseases. According to the neurovascular hypothesis, neuroinflammation may promote the activation and sensitisation of meningeal nociceptors, inducing the persistent throbbing headache characterized in migraine. The tumor necrosis factor (TNF) gene cluster, made up of TNF?, lymphotoxin ? (LTA), and lymphotoxin ? (LTB), has been implicated to influence the intensity and duration of local inflammation. It is thought that sterile inflammation mediated by LTA, LTB, and TNF? contributes to threshold brain excitability, propagation of neuronal hyperexcitability and thus initiation and maintenance of a migraine attack. Previous studies have investigated variants within the TNF gene cluster region in relation to migraine susceptibility, with largely conflicting results. The aim of this study was to expand on previous research and utilize a large case-control cohort and range of variants within the TNF gene cluster to investigate the role of the TNF gene cluster in migraine. Nine single nucleotide polymorphisms (SNPs) were selected for investigation as follows: rs1800683, rs2229094, rs2009658, rs2071590, rs2239704, rs909253, rs1800630, rs1800629, and rs3093664. No significant association with migraine susceptibility was found for any of the SNPs tested, with further testing according to migraine subtype and gender also showing no association for disease risk. Haplotype analysis showed that none of the tested haplotypes were significantly associated with migraine. PMID:24054031

Stuart, Shani; Maher, Bridget H; Sutherland, Heidi; Benton, Miles; Rodriguez, Astrid; Lea, Rod A; Haupt, Larisa M; Griffiths, Lyn R

2013-12-01

124

Causes and consequences of genetic background effects illuminated by integrative genomic analysis.  

PubMed

The phenotypic consequences of individual mutations are modulated by the wild-type genetic background in which they occur. Although such background dependence is widely observed, we do not know whether general patterns across species and traits exist or about the mechanisms underlying it. We also lack knowledge on how mutations interact with genetic background to influence gene expression and how this in turn mediates mutant phenotypes. Furthermore, how genetic background influences patterns of epistasis remains unclear. To investigate the genetic basis and genomic consequences of genetic background dependence of the scalloped(E3) allele on the Drosophila melanogaster wing, we generated multiple novel genome-level datasets from a mapping-by-introgression experiment and a tagged RNA gene expression dataset. In addition we used whole genome resequencing of the parental lines-two commonly used laboratory strains-to predict polymorphic transcription factor binding sites for SD. We integrated these data with previously published genomic datasets from expression microarrays and a modifier mutation screen. By searching for genes showing a congruent signal across multiple datasets, we were able to identify a robust set of candidate loci contributing to the background-dependent effects of mutations in sd. We also show that the majority of background-dependent modifiers previously reported are caused by higher-order epistasis, not quantitative noncomplementation. These findings provide a useful foundation for more detailed investigations of genetic background dependence in this system, and this approach is likely to prove useful in exploring the genetic basis of other traits as well. PMID:24504186

Chandler, Christopher H; Chari, Sudarshan; Tack, David; Dworkin, Ian

2014-04-01

125

Genetically Determined Susceptibility to Tuberculosis in Mice Causally Involves Accelerated and Enhanced Recruitment of Granulocytes  

PubMed Central

Classical twin studies and recent linkage analyses of African populations have revealed a potential involvement of host genetic factors in susceptibility or resistance to Mycobacterium tuberculosis infection. In order to identify the candidate genes involved and test their causal implication, we capitalized on the mouse model of tuberculosis, since inbred mouse strains also differ substantially in their susceptibility to infection. Two susceptible and two resistant mouse strains were aerogenically infected with 1,000 CFU of M. tuberculosis, and the regulation of gene expression was examined by Affymetrix GeneChip U74A array with total lung RNA 2 and 4 weeks postinfection. Four weeks after infection, 96 genes, many of which are involved in inflammatory cell recruitment and activation, were regulated in common. One hundred seven genes were differentially regulated in susceptible mouse strains, whereas 43 genes were differentially expressed only in resistant mice. Data mining revealed a bias towards the expression of genes involved in granulocyte pathophysiology in susceptible mice, such as an upregulation of those for the neutrophil chemoattractant LIX (CXCL5), interleukin 17 receptor, phosphoinositide kinase 3 delta, or gamma interferon-inducible protein 10. Following M. tuberculosis challenge in both airways or peritoneum, granulocytes were recruited significantly faster and at higher numbers in susceptible than in resistant mice. When granulocytes were efficiently depleted by either of two regimens at the onset of infection, only susceptible mice survived aerosol challenge with M. tuberculosis significantly longer than control mice. We conclude that initially enhanced recruitment of granulocytes contributes to susceptibility to tuberculosis.

Keller, Christine; Hoffmann, Reinhard; Lang, Roland; Brandau, Sven; Hermann, Corinna; Ehlers, Stefan

2006-01-01

126

Patient understanding of and responses to multiplex genetic susceptibility test results  

PubMed Central

Purpose Examination of patients’ responses to direct-to-consumer genetic susceptibility tests is needed to inform clinical practice. This study examined patients’ recall and interpretation of, and responses to, genetic susceptibility test results provided directly by mail. Methods This observational study had 3 prospective assessments (before testing; 10 days after receiving results; 3 months later). Participants were 199 patients aged 25–40 who received free genetic susceptibility testing for 8 common health conditions. Results Over 80% correctly recalled their results for the 8 health conditions. Patients were unlikely to interpret genetic results as deterministic of health outcomes (mean=6.0, SD=0.8 on 1–7 scale, 1 indicating strongly deterministic). In multivariate analyses, patients with the least deterministic interpretations were White (p=.0098), more educated (p=.0093), and least confused by results (p=.001). Only 1% talked about their results with a provider. Conclusion Findings suggest that most patients will correctly recall their results and will not interpret genetics as the sole cause of diseases. The subset of those confused by results could benefit from consultation with a health care provider, which could emphasize that health habits currently are the best predictors of risk. Providers could leverage patients’ interest in genetic tests to encourage behavior changes to reduce disease risk.

Kaphingst, Kimberly A.; McBride, Colleen M.; Wade, Christopher; Alford, Sharon Hensley; Reid, Robert; Larson, Eric; Baxevanis, Andreas D.; Brody, Lawrence C.

2012-01-01

127

Genetic susceptibility to myocardial infarction and coronary artery disease.  

PubMed

Atherosclerotic involvement in the coronary arteries, which can result in heart attack and sudden death, is a common disease and prototypic of a complex human trait. To understand its genomic basis, eight linkage studies of sibling pairs have been performed. Although there was limited inter-study concordance of important loci, two gene variants in the leukotriene pathway (ALOX5AP and LTA4) have emerged as susceptibility factors for myocardial infarction (MI). Genome-wide association studies have also been undertaken, and the pro-inflammatory cytokine lymphotoxin-alpha (LTA), and its key ligand galectin-2 (LGALS2) have been identified as genes implicated in predisposition for heart attack. By cueing into the genomic basis for low serum LDL cholesterol levels, much work has been done to advance the importance of the serine protease PCSK9, which modulates LDL receptor function. Lifelong lowered LDL cholesterol associated with PCSK9 point mutations in 2-3% of individuals have been shown to provide marked protection from coronary artery disease (CAD). Most of the success in this field has been with the phenotype of MI, which is considerably more restrictive than CAD. Four principal and interdependent processes--lipoprotein handling, endothelial integrity, arterial inflammation, and thrombosis--have been supported as important via the clustering of genes, thus far implicated in CAD susceptibility. Of note, connecting genes in a single pathway (leukotriene), of a protein and its ligand (LTAalpha) or from one disease to another [age-related macular degeneration (AMD); complement factor H (CFH)], or even three disease characterized by inflammation (MHC2) have now been reported. Although the population attributable risk for any of the genes identified to date is limited, such discovery is likely to be accelerated in the future. PMID:16987874

Topol, Eric J; Smith, Jonathan; Plow, Edward F; Wang, Qing K

2006-10-15

128

Genetic background modulates phenotypes of serotonin transporter Ala56 knock-in mice  

PubMed Central

Background Previously, we identified multiple, rare serotonin (5-HT) transporter (SERT) variants in children with autism spectrum disorder (ASD). Although in our study the SERT Ala56 variant was over-transmitted to ASD probands, it was also seen in some unaffected individuals, suggesting that associated ASD risk is influenced by the epistatic effects of other genetic variation. Subsequently, we established that mice expressing the SERT Ala56 variant on a 129S6/S4 genetic background display multiple biochemical, physiological and behavioral changes, including hyperserotonemia, altered 5-HT receptor sensitivity, and altered social, communication, and repetitive behavior. Here we explore the effects of genetic background on SERT Ala56 knock-in phenotypes. Methods To explore the effects of genetic background, we backcrossed SERT Ala56 mice on the 129 background into a C57BL/6 (B6) background to achieve congenic B6 SERT Ala56 mice, and assessed autism-relevant behavior, including sociability, ultrasonic vocalizations, and repetitive behavior in the home cage, as well as serotonergic phenotypes, including whole blood serotonin levels and serotonin receptor sensitivity. Results One consistent phenotype between the two strains was performance in the tube test for dominance, where mutant mice displayed a greater tendency to withdraw from a social encounter in a narrow tube as compared to wildtype littermate controls. On the B6 background, mutant pup ultrasonic vocalizations were significantly increased, in contrast to decreased vocalizations seen previously on the 129 background. Several phenotypes seen on the 129 background were reduced or absent when the mutation was placed on the B6 background, including hyperserotonemia, 5-HT receptor hypersensivity, and repetitive behavior. Conclusions Our findings provide a cogent example of how epistatic interactions can modulate the impact of functional genetic variation and suggest that some aspects of social behavior may be especially sensitive to changes in SERT function. Finally, these results provide a platform for the identification of genes that may modulate the risk of ASD in humans.

2013-01-01

129

Genetic factors in Haemophilus influenzae type b disease susceptibility and antibody acquisition.  

PubMed

Because Alaskan Eskimos have the greatest known endemic risk of Haemophilus influenzae type b (Hib) disease and represent a comparatively homogeneous population, we selected this population to evaluate the presence or absence of an association of 35 genetic markers (alleles or allotypes) at 12 chromosomal loci with susceptibility to both invasive Hib disease risk and level of Hib anticapsular antibody. We studied nearly all Alaskan Eskimo children who had had invasive Hib disease between 1971 and 1982 in southwestern Alaska (n = 103) and an equivalent number of controls matched for age, race, and village of residence, and verified not to have had proved or suspected Hib disease. We found no significant associations with Hib disease for the single alleles of HLA-A, -B, -C, -DR, Gm, Km, Am, Kidd, MNSs, ABO, esterase D, or glutamate pyruvate transaminase loci. However, we observed a significant interaction of two loci, Gm(a;..;g,s,t) allotype and HLA-DR8 (P = 0.002), with increased Hib disease susceptibility, and an interaction of the same Gm allotype and HLA-DR5 with decreased disease susceptibility (P = 0.01). We also compared the level of anticapsular antibody to Hib with each genetic marker and two-locus interactions, but no genetic association with antibody level was found. We conclude that some genetic factors contribute to the susceptibility to invasive Hib disease in this population. PMID:3492597

Petersen, G M; Silimperi, D R; Rotter, J I; Terasaki, P I; Schanfield, M S; Park, M S; Ward, J I

1987-02-01

130

Pharmacogenetic analysis of adverse drug effect reveals genetic variant for susceptibility to liver toxicity  

Microsoft Academic Search

A retrospective pharmacogenetic study was conducted to identify possible genetic susceptibility factors in patients in whom the administration of the anti-Parkinson drug, tolcapone (TASMAR®), was associated with hepatic toxicity. We studied 135 cases of patients with elevated liver transaminase levels (ELT) of ?1.5 times above the upper limit of normal, in comparison with matched controls that had also received the

Gonzalo Acuña; Dorothee Foernzler; Diane Leong; Michael Rabbia; Ralf Smit; Ernest Dorflinger; Rodolfo Gasser; Josephine Hoh; Jürg Ott; Edilio Borroni; Zung To; Annick Thompson; Jia Li; Lara Hashimoto; Klaus Lindpaintner

2002-01-01

131

Neutrophil Responses to Mycobacterium tuberculosis Infection in Genetically Susceptible and Resistant Mice  

Microsoft Academic Search

The role of neutrophils in tuberculosis (TB) resistance and pathology is poorly understood. Neutrophil reactions are meant to target the offending pathogen but may lead to destruction of the host lung tissue, making the defending cells an enemy. Here, we show that mice of the I\\/St strain which are genetically susceptible to TB show an unusually high and prolonged neutrophil

Evgenyi B. Eruslanov; Irina V. Lyadova; Tatiana K. Kondratieva; Konstantin B. Majorov; Ilya V. Scheglov; Marianna O. Orlova; Alexander S. Apt

2005-01-01

132

Genetic susceptibility to severe course of nephropathia epidemica caused by Puumala hantavirus  

Microsoft Academic Search

Genetic susceptibility to severe course of nephropathia epidemica caused by Puumala hantavirus. Nephropathia epidemica (NE) caused by Puumala hantavirus is one type of hemorrhagic fever with renal syndrome (HFRS). There is considerable variability in the clinical severity of NE. Many infections are subclinical but the disease can even be fatal. We questioned whether the wide spectrum in the outcome of

Jukka Mustonen; Jukka Partanen; Mari Kanerva; Kari Pietilä; Olli Vapalahti; Amos Pasternack; Antti Vaheri

1996-01-01

133

ORAI1 Genetic Polymorphisms Associated with the Susceptibility of Atopic Dermatitis in Japanese and Taiwanese Populations  

Microsoft Academic Search

Atopic dermatitis is a chronic inflammatory skin disease. Multiple genetic and environmental factors are thought to be responsible for susceptibility to AD. In this study, we collected 2,478 DNA samples including 209 AD patients and 729 control subjects from Taiwanese population and 513 AD patients and 1027 control subject from Japanese population for sequencing and genotyping ORAI1. A total of

Wei-Chiao Chang; Chih-Hung Lee; Tomomitsu Hirota; Li-Fang Wang; Satoru Doi; Akihiko Miyatake; Tadao Enomoto; Kaori Tomita; Masafumi Sakashita; Takechiyo Yamada; Shigeharu Fujieda; Koji Ebe; Hidehisa Saeki; Satoshi Takeuchi; Masutaka Furue; Wei-Chiao Chen; Yi-Ching Chiu; Wei Pin Chang; Chien-Hui Hong; Edward Hsi; Suh-Hang Hank Juo; Hsin-Su Yu; Yusuke Nakamura; Mayumi Tamari

2012-01-01

134

BLACK AND WHITE ADULTS' PERSPECTIVES ON THE GENETICS OF NICOTINE ADDICTION SUSCEPTIBILITY  

PubMed Central

Aims Emerging research may soon lead to improved quit rates via genetically-tailored smoking cessation treatment. The purpose of this study was to explore individuals’ beliefs and attitudes about genetic testing in this context, and how these may differ across racial groups. Design Two site qualitative study. Methods Eleven focus groups were conducted in 2007 with 51 Black and 55 White adult participants in Montgomery, AL and Baltimore, MD. Measurements Questions were asked about smoking as an addiction, the role of genetics in nicotine addiction susceptibility, and undergoing genetic testing to receive tailored smoking cessation treatment. Data were analyzed using content analysis. Findings Most participants believed that smoking was an addiction yet were unwilling to endorse the notion that genetics played a role in nicotine addiction susceptibility. However, 91% of White participants and 62% of Black participants indicated that they would likely take a genetic test that would match them to their optimal smoking cessation treatment. The primary potential benefit was a vague sense that additional knowledge about oneself would be of value. Primary barriers included disinterest and skepticism about the test, unwillingness to believe that genetics played a role in nicotine addiction or treatment response, and concerns about psychological consequences. Conclusions The majority of participants, particularly Black participants, did not believe that genetics played a significant role in nicotine addiction susceptibility but were willing to undergo genetic testing. Participants identified some benefit to tailoring smoking treatment by genotype. However, participants also expressed skepticism about the test and concerns about its consequences; these issues would need to be addressed in the clinical encounter.

Park, Elyse R.; Kleimann, Susan; Youatt, Emily J.; Lockhart, Abigail; Campbell, Eric G.; Levy, Douglas E.; Halbert, Chanita Hughes; Schmieder, Erin; Krishna, Rasika; Shields, Alexandra E.

2013-01-01

135

Variation in Short Tandem Repeats Is Deeply Structured by Genetic Background on the Human Y Chromosome  

PubMed Central

Summary Eleven biallelic polymorphisms and seven short-tandem-repeat (STR) loci mapping on the nonrecombining portion of the human Y chromosome have been typed in men from northwestern Africa. Analysis of the biallelic markers, which represent probable unique events in human evolution, allowed us to characterize the stable backgrounds or haplogroups of Y chromosomes that prevail in this geographic region. Variation in the more rapidly mutating genetic markers (STRs) has been used both to estimate the time to the most recent common ancestor for STR variability within these stable backgrounds and to explore whether STR differentiation among haplogroups still retains information about their phylogeny. When analysis of molecular variance was used to study the apportionment of STR variation among both genetic backgrounds (i.e., those defined by haplogroups) and population backgrounds, we found STR variability to be clearly structured by haplogroups. More than 80% of the genetic variance was found among haplogroups, whereas only 3.72% of the genetic variation could be attributed to differences among populations—that is, genetic variability appears to be much more structured by lineage than by population. This was confirmed when two population samples from the Iberian Peninsula were added to the analysis. The deep structure of the genetic variation in old genealogical units (haplogroups) challenges a population-based perspective in the comprehension of human genome diversity. A population may be better understood as an association of lineages from a deep and population-independent gene genealogy, rather than as a complete evolutionary unit.

Bosch, Elena; Calafell, Francesc; Santos, Fabricio R.; Perez-Lezaun, Anna; Comas, David; Benchemsi, Noufissa; Tyler-Smith, Chris; Bertranpetit, Jaume

1999-01-01

136

Genetic variation in the NBS1, MRE11, RAD50 and BLM genes and susceptibility to non-Hodgkin lymphoma  

PubMed Central

Background Translocations are hallmarks of non-Hodgkin lymphoma (NHL) genomes. Because lymphoid cell development processes require the creation and repair of double stranded breaks, it is not surprising that disruption of this type of DNA repair can cause cancer. The members of the MRE11-RAD50-NBS1 (MRN) complex and BLM have central roles in maintenance of DNA integrity. Severe mutations in any of these genes cause genetic disorders, some of which are characterized by increased risk of lymphoma. Methods We surveyed the genetic variation in these genes in constitutional DNA of NHL patients by means of gene re-sequencing, then conducted genetic association tests for susceptibility to NHL in a population-based collection of 797 NHL cases and 793 controls. Results 114 SNPs were discovered in our sequenced samples, 61% of which were novel and not previously reported in dbSNP. Although four variants, two in RAD50 and two in NBS1, showed association results suggestive of an effect on NHL, they were not significant after correction for multiple tests. Conclusion These results suggest an influence of RAD50 and NBS1 on susceptibility to diffuse large B-cell lymphoma and marginal zone lymphoma. Larger association and functional studies could confirm such a role.

2009-01-01

137

Genetic determinants of susceptibility to Mycobacterial infections: IRF8, a new kid on the block.  

PubMed

Genetic and population studies suggest that onset, progression and ultimate outcome of infection with Mycobacteria, including the agent of tuberculosis Mycobacterium tuberculosis, are strongly influenced by genetic factors. Family-based and case-control linkage and association studies have suggested a complex genetic component for susceptibility to tuberculosis. On the other hand, patients with inborn errors in the IL12/IFN? circuit may develop disseminated mycobacterial infections following perinatal BCG vaccination. The study of such MSMD (Mendelian Susceptibility to Mycobacterial Diseases) patients has provided much insight into innate and acquired immune defenses against mycobacteria. Parallel genetic analyses in mouse models of mycobacterial infections have also indicated complex genetic control, and have provided candidate genes for parallel testing in humans. Recently, mutations in human IRF8 were discovered and shown to cause two distinct forms of a novel primary immunodeficiency and associated susceptibility to mycobacteria. Autosomal recessive IRF8 deficiency is caused by mutation K108E and associated with severe disease with complete depletion of monocytes and dendritic cells. Mutation T80A causes autosomal dominant IRF8 deficiency and a milder form of the disease with selective loss of a subset of dendritic cells. These findings have established that IRF8 is required for ontogeny of the myeloid lineage and for host response to mycobacteria. The ongoing study of the IRF8 transcriptome has shown promise for the identification of IRF8 dependent pathways that play a critical role in host defense against mycobacteria in particular, and against intracellular pathogens in general. PMID:23468103

Salem, S; Gros, P

2013-01-01

138

Insights into physiological and genetic mupirocin susceptibility in bifidobacteria.  

PubMed

Mupirocin is an antibiotic commonly used in selective media for the isolation of bifidobacteria. However, little is known about the genetic traits responsible for bifidobacterial resistance to mupirocin. Our investigation demonstrates that all of the bifidobacteria tested exhibit a phenotype of generally high resistance to this antibiotic. The genotypic reason for bifidobacterial mupirocin resistance was further characterized by sequencing of the isoleucyl-tRNA synthetase gene (ileS) coupled with three-dimensional modeling of the encoded protein and cloning of the ileS gene of Bifidobacterium bifidum PRL2010 in a mupirocin-sensitive Escherichia coli strain. These analyses revealed key amino acid residues of the IleS protein that apparently are crucial for conferring a mupirocin resistance phenotype to bifidobacteria. PMID:21421794

Serafini, Fausta; Bottacini, Francesca; Viappiani, Alice; Baruffini, Enrico; Turroni, Francesca; Foroni, Elena; Lodi, Tiziana; van Sinderen, Douwe; Ventura, Marco

2011-05-01

139

Insights into Physiological and Genetic Mupirocin Susceptibility in Bifidobacteria?  

PubMed Central

Mupirocin is an antibiotic commonly used in selective media for the isolation of bifidobacteria. However, little is known about the genetic traits responsible for bifidobacterial resistance to mupirocin. Our investigation demonstrates that all of the bifidobacteria tested exhibit a phenotype of generally high resistance to this antibiotic. The genotypic reason for bifidobacterial mupirocin resistance was further characterized by sequencing of the isoleucyl-tRNA synthetase gene (ileS) coupled with three-dimensional modeling of the encoded protein and cloning of the ileS gene of Bifidobacterium bifidum PRL2010 in a mupirocin-sensitive Escherichia coli strain. These analyses revealed key amino acid residues of the IleS protein that apparently are crucial for conferring a mupirocin resistance phenotype to bifidobacteria.

Serafini, Fausta; Bottacini, Francesca; Viappiani, Alice; Baruffini, Enrico; Turroni, Francesca; Foroni, Elena; Lodi, Tiziana; van Sinderen, Douwe; Ventura, Marco

2011-01-01

140

DCDC2 Genetic Variants and Susceptibility to Developmental Dyslexia  

PubMed Central

Objective(s) Developmental Dyslexia is a heritable condition, with genetic factors accounting for 44%–75% of the variance in performance tests of reading component subphenotypes. Compelling genetic linkage and association evidence supports a quantitative trait locus in the 6p21.3 region, which encodes a gene called DCDC2. In the present study, we explored the contribution of two DCDC2 markers to dyslexia, related reading and memory phenotypes in nuclear families of Italian origin. Methods 303 nuclear families recruited on the basis of having a proband with Developmental Dyslexia have been studied with 6p21.3 markers, BV677278 and rs793862. Marker-trait association was investigated by the quantitative transmission disequilibrium test (QTDT, version 2.5.1) as modelled by Abecasis et al. (2000), which allows for the analyses of quantitative traits. Seven phenotypes were used in association analyses, i.e. word and non-word reading, word and non-word spelling, orthographic choice, memory and the affected status based on inclusion criteria. Results QTDT analyses yielded evidence for association between reading skills and the BV677278 deletion (empirical p-values= .025–.029) and between memory and BV677278 allele 10 (empirical p-value= .0001). Conclusions Our result adds further evidence in support of DCDC2 contributing to the deficits in Developmental Dyslexia. More specifically, our data support the view that DCDC2 influences both reading and memory impairments thus shedding further light into the etiologic basis and the phenotypic complexity of Developmental Dyslexia.

Marino, Cecilia; Meng, Haiying; Mascheretti, Sara; Rusconi, Marianna; Cope, Natalie; Giorda, Roberto; Molteni, Massimo; Gruen, Jeffrey R

2011-01-01

141

Role of Toll-like receptor-4 in genetic susceptibility to lung injury induced by residual oil fly ash.  

PubMed

The mechanisms of susceptibility to particle-induced lung injury are not clearly understood. To evaluate the contribution of genetic background to pulmonary pathogenesis, we compared the lung injury responses to residual oil fly ash (ROFA) in inbred mouse strains and calculated heritability estimates. Significant interstrain (genetic) variation was observed in ROFA-induced lung inflammation and hyperpermeability phenotypes; broad-sense heritability ranged from approximately 0.43 to 0.62, and the coefficient of genetic determination ranged from 0.28 to 0.45. C3H/HeJ (HeJ) mice were most resistant to the ROFA-induced injury responses. This was particularly important, as HeJ mice contain a dominant negative mutation in Toll-like receptor-4 (Tlr4). We then characterized ROFA-induced injury and TLR4 signaling in HeJ mice and its coisogenic strain C3H/HeOuJ (OuJ; Tlr4 normal) to understand the potential role of Tlr4 in this model. ROFA-induced lung injury was significantly greater in OuJ mice compared with HeJ mice. ROFA also significantly enhanced transcript and protein levels of lung TLR4 in OuJ but not in HeJ mice. Greater activation of downstream signal molecules (i.e., MYD88, TRAF6, IRAK-1, NF-kappaB, MAPK, AP-1) was observed in OuJ mice than in HeJ mice before the development of ROFA-induced pulmonary injury. Putative TLR4-dependent inflammatory genes that were differentially induced by ROFA in the two strains include interleukin-1beta and tumor necrosis factor-alpha. Results support an important contribution of genetic background to particle-mediated lung injury, and Tlr4 is a candidate susceptibility gene. PMID:15784698

Cho, Hye-Youn; Jedlicka, Anne E; Clarke, Robert; Kleeberger, Steven R

2005-06-16

142

Borna disease virus-induced neuronal degeneration dependent on host genetic background and prevented by soluble factors  

PubMed Central

Infection of newborn rats with Borne disease virus (BDV) results in selective degeneration of granule cell neurons of the dentate gyrus (DG). To study cellular countermechanisms that might prevent this pathology, we screened for rat strains resistant to this BDV-induced neuronal degeneration. To this end, we infected hippocampal slice cultures of different rat strains with BDV and analyzed for the preservation of the DG. Whereas infected cultures of five rat strains, including Lewis (LEW) rats, exhibited a disrupted DG cytoarchitecture, slices of three other rat strains, including Sprague–Dawley (SD), were unaffected. However, efficiency of viral replication was comparable in susceptible and resistant cultures. Moreover, these rat strain–dependent differences in vulnerability were replicated in vivo in neonatally infected LEW and SD rats. Intriguingly, conditioned media from uninfected cultures of both LEW and SD rats could prevent BDV-induced DG damage in infected LEW hippocampal cultures, whereas infection with BDV suppressed the availability of these factors from LEW but not in SD hippocampal cultures. To gain further insights into the genetic basis for this rat strain–dependent susceptibility, we analyzed DG granule cell survival in BDV-infected cultures of hippocampal neurons derived from the F1 and F2 offspring of the crossing of SD and LEW rats. Genome-wide association analysis revealed one resistance locus on chromosome (chr) 6q16 in SD rats and, surprisingly, a locus on chr3q21-23 that was associated with susceptibility. Thus, BDV-induced neuronal degeneration is dependent on the host genetic background and is prevented by soluble protective factors in the disease-resistant SD rat strain.

Wu, Yuan-Ju; Schulz, Herbert; Lin, Chia-Ching; Saar, Kathrin; Patone, Giannino; Fischer, Heike; Hubner, Norbert; Heimrich, Bernd; Schwemmle, Martin

2013-01-01

143

Modifying Behavioral Phenotypes in Fmr1 KO Mice: Genetic Background Differences Reveal Autistic-Like Responses  

PubMed Central

Scientific Abstract Fragile X syndrome (FXS) is the most common inherited form of intellectual disability in humans. In addition to cognitive impairment, patients may exhibit hyperactivity, attention deficits, social difficulties and anxiety, and autistic-like behaviors. The degree to which patients display these behaviors varies considerably and is influenced by family history, suggesting that genetic modifiers play a role in the expression of behaviors in FXS. Several studies have examined behavior in a mouse model of FXS in which the Fmr1 gene has been ablated. Most of those studies were done in Fmr1 knockout mice on a pure C57BL/6 or FVB strain background. To gain a better understanding of the effects of genetic background on behaviors resulting from the loss of Fmr1 gene expression, we generated F1 hybrid lines from female Fmr1 heterozygous mice on a pure C57BL/6J background bred with male Fmr1 wild-type mice of various background strains (A/J, DBA/2J, FVB/NJ, 129S1/SvImJ and CD-1). Male Fmr1 knockout and wild-type littermates from each line were examined in an extensive behavioral test battery. Results clearly indicate that multiple behavioral responses are dependent on genetic background, including autistic-like traits that are present on limited genetic backgrounds. This approach has allowed us to identify improved models for different behavioral symptoms present in FXS including autistic-like traits.

Spencer, Corinne M.; Alekseyenko, Olga; Hamilton, Shannon M.; Thomas, Alexia M.; Serysheva, Ekaterina; Yuva-Paylor, Lisa A.; Paylor, Richard

2010-01-01

144

Differences in Genetic Background Between Active Smokers, Passive Smokers, and Non-Smokers With Crohn's Disease  

Microsoft Academic Search

OBJECTIVES:Smoking behavior and genetic variations are important factors for the development of Crohn's disease (CD), but studies investigating the interaction between smoking and genetic background are scarce. We studied allelic associations of 19 confirmed variants located in 14 CD-associated genes or loci, in CD patients stratified for active smoking at diagnosis and passive smoking in childhood.METHODS:Genotyping data of 19 CD-associated

Frans van der Heide; Ilja M Nolte; Jan H Kleibeuker; Cisca Wijmenga; Gerard Dijkstra; Rinse K Weersma

2010-01-01

145

Genetic susceptibility to Chagas disease cardiomyopathy: involvement of several genes of the innate immunity and chemokine-dependent migration pathways  

PubMed Central

Background Chagas disease, caused by the protozoan Trypanosoma cruzi is endemic in Latin America. Thirty percent of infected individuals develop chronic Chagas cardiomyopathy (CCC), an inflammatory dilated cardiomyopathy that is, by far, the most important clinical consequence of T. cruzi infection. The others remain asymptomatic (ASY). A possible genetic component to disease progression was suggested by familial aggregation of cases and the association of markers of innate and adaptive immunity genes with CCC development. Migration of Th1-type T cells play a major role in myocardial damage. Methods Our genetic analysis focused on CCR5, CCL2 and MAL/TIRAP genes. We used the Tag SNPs based approach, defined to catch all the genetic information from each gene. The study was conducted on a large Brazilian population including 315 CCC cases and 118 ASY subjects. Results The CCL2rs2530797A/A and TIRAPrs8177376A/A were associated to an increase susceptibility whereas the CCR5rs3176763C/C genotype is associated to protection to CCC. These associations were confirmed when we restricted the analysis to severe CCC, characterized by a left ventricular ejection fraction under 40%. Conclusions Our data show that polymorphisms affecting key molecules involved in several immune parameters (innate immunity signal transduction and T cell/monocyte migration) play a role in genetic susceptibility to CCC development. This also points out to the multigenic character of CCC, each polymorphism imparting a small contribution. The identification of genetic markers for CCC will provide information for pathogenesis as well as therapeutic targets.

2013-01-01

146

Statin myotoxicity: a review of genetic susceptibility factors.  

PubMed

The 3-hydroxy-3-methylglutaryl coenzyme A (HMGCoA) reductase inhibitors (statins) are among the most common medications prescribed worldwide, but their efficacy and toxicity vary between individuals. One of the major factors contributing to intolerance and non-compliance are the muscle side-effects, which range from mild myalgia through to severe life-threatening rhabdomyolysis. One way to address this is pharmacogenomic screening, which aims to individualize therapy to maximize efficacy whilst avoiding toxicity. Genes encoding proteins involved in the metabolism of statins as well as genes known to cause inherited muscle disorders have been investigated. To-date only polymorphisms in the SLCO1B1 gene, which encodes the protein responsible for hepatic uptake of statins, and the COQ2 gene, important in the synthesis of coenzyme Q10, have been validated as being strongly associated with statin-induced myopathy. The aim of this review is to summarize studies investigating genetic factors predisposing to statin myopathy and myalgia, as the first step towards pharmacogenomic screening to identify at risk individuals. PMID:24176465

Needham, M; Mastaglia, F L

2014-01-01

147

The adiponectin gene, ADIPOQ, and genetic susceptibility to colon cancer  

PubMed Central

In order to evaluate the contribution of polymorphisms of the adiponectin gene, ADIPOQ, to the risk of colon cancer, we conducted a case-control study of 60 colon cancer patients and 60 age, gender and ethnicity-matched controls in the Saudi population. We tested the hypothesis by analyzing the genotypes for two single nucleotide polymorphisms (SNPs), rs1501299 (G276T) and rs2241766 (T45G), in the ADIPOQ gene. In addition, the study was also designed to assess whether the two SNPs contribute to circulating adiponectin levels. We observed an increased risk of colon cancer associated with the 276T allele. The odds ratio (OR) was 2.64 [95% confidence interval (CI), 0.49–14.6]. The G allele at the T45G polymorphism was associated with a lower risk of colon cancer (OR=0.41; 95% CI, 0.19–0.86). Our results suggest that the risk of developing colon cancer may be partially explained by genetic polymorphisms in the ADIPOQ gene.

AL-HARITHY, ROWYDA N.; AL-ZAHRANI, MARYAM H.

2012-01-01

148

Genetic Control of Susceptibility to Porphyromonas gingivalis-Induced Alveolar Bone Loss in Mice  

PubMed Central

Periodontal disease affects a large percentage of the human population. Resorption of the alveolar bone of the jaw is a pivotal sequela of periodontal disease, because this bone is the attachment site for the periodontal ligaments that anchor the teeth. Using a murine model in which alveolar bone loss is induced by oral infection with Porphyromonas gingivalis, a gram-negative bacterium associated with human adult periodontal disease, we provide evidence suggesting that susceptibility to such bone loss is a genetically determined trait. AKR/J, DBA/2J, and BALB/cByJ or BALB/cJ mice were highly susceptible, while A/J, A/HeJ, 129/J, SJL/J, and C57BL/6J mice were much more resistant. When susceptible BALB/cJ and BALB/cByJ mice were crossed to resistant strains, two patterns were observed. (BALBc/ByJ × C57BL/6J)F1 offspring were susceptible, suggesting C57BL/6J has recessive resistance alleles, while (BALB/cJ × A/J)F1 mice were all resistant, suggesting that A/J mice have dominant resistance alleles. These results suggest a tractable genetic basis for P. gingivalis-induced alveolar bone loss and open the possibility of exploiting the mouse model to identify loci important for host susceptibility and resistance to periodontal disease.

Baker, Pamela J.; Dixon, Mark; Roopenian, Derry C.

2000-01-01

149

An intervention study of smoking cessation with feedback on genetic cancer susceptibility in Japan  

Microsoft Academic Search

Background.To evaluate whether feedback of genetic information regarding an L-myc polymorphism, identified as impacting on tobacco-related cancer risk, has an influence on smoking cessation, an intervention study was conducted.

Hidemi Ito; Keitaro Matsuo; Kenji Wakai; Toshiko Saito; Hiroshi Kumimoto; Katashi Okuma; Kazuo Tajima; Nobuyuki Hamajima

2006-01-01

150

Application of a hybrid model of neural networks and genetic algorithms to evaluate landslide susceptibility  

NASA Astrophysics Data System (ADS)

In the last few decades, the development of Geographical Information Systems (GIS) technology has provided a method for the evaluation of landslide susceptibility and hazard. Slope units were found to be appropriate for the fundamental morphological elements in landslide susceptibility evaluation. Following the DEM construction in a loess area susceptible to landslides, the direct-reverse DEM technology was employed to generate 216 slope units in the studied area. After a detailed investigation, the landslide inventory was mapped in which 39 landslides, including paleo-landslides, old landslides and recent landslides, were present. Of the 216 slope units, 123 involved landslides. To analyze the mechanism of these landslides, six environmental factors were selected to evaluate landslide occurrence: slope angle, aspect, the height and shape of the slope, distance to river and human activities. These factors were extracted in terms of the slope unit within the ArcGIS software. The spatial analysis demonstrates that most of the landslides are located on convex slopes at an elevation of 100-150 m with slope angles from 135°-225° and 40°-60°. Landslide occurrence was then checked according to these environmental factors using an artificial neural network with back propagation, optimized by genetic algorithms. A dataset of 120 slope units was chosen for training the neural network model, i.e., 80 units with landslide presence and 40 units without landslide presence. The parameters of genetic algorithms and neural networks were then set: population size of 100, crossover probability of 0.65, mutation probability of 0.01, momentum factor of 0.60, learning rate of 0.7, max learning number of 10 000, and target error of 0.000001. After training on the datasets, the susceptibility of landslides was mapped for the land-use plan and hazard mitigation. Comparing the susceptibility map with landslide inventory, it was noted that the prediction accuracy of landslide occurrence is 93.02%, whereas units without landslide occurrence are predicted with an accuracy of 81.13%. To sum up, the verification shows satisfactory agreement with an accuracy of 86.46% between the susceptibility map and the landslide locations. In the landslide susceptibility assessment, ten new slopes were predicted to show potential for failure, which can be confirmed by the engineering geological conditions of these slopes. It was also observed that some disadvantages could be overcome in the application of the neural networks with back propagation, for example, the low convergence rate and local minimum, after the network was optimized using genetic algorithms. To conclude, neural networks with back propagation that are optimized by genetic algorithms are an effective method to predict landslide susceptibility with high accuracy.

Wang, H. B.; Li, J. W.; Zhou, B.; Yuan, Z. Q.; Chen, Y. P.

2013-03-01

151

XCIND as a genetic disease of X-irradiation hypersensitivity and cancer susceptibility.  

PubMed

The XCIND syndrome is named after distinct hypersensitivity to ionizing (X-ray) irradiation, cancer susceptibility, immunodeficiency, neurological abnormality, and double-strand DNA breakage. The disorders comprising XCIND syndrome are usually inherited in an autosomal recessive manner. Ataxia telangiectasia (A-T) is one such disease, and is caused by biallelic germline mutation of the Ataxia telangiectasia mutated (ATM) gene. Heterozygous carriers of the ATM mutation, who do not show A-T-like clinical symptoms, are estimated to comprise 1 % of the population. Thus, understanding the biological basis of XCIND, including A-T, should help shed light on the pathogenesis of genetic diseases with cancer susceptibility. PMID:23266960

Mizutani, Shuki; Takagi, Masatoshi

2013-01-01

152

From degeneration to genetic susceptibility, from eugenics to genethics, from Bezugsziffer to LOD score: the history of psychiatric genetics.  

PubMed

Reviewing the history of psychiatric genetics is a difficult task, since--in contrast to genetic research into most other disorders--it cannot simply be done by chronologically listing methodological achievements and major findings. Instead, it necessitates a comprehensive assessment of how the aetiological concept of mental disorders has developed since as early as the world of ancient Greece. Furthermore, it has to touch upon the sensitive issue of the eugenic movement that was closely linked to the study of heredity in mental disorders in the first half of the 20th century and, in Nazi Germany, led to the systematic mass murder of psychiatric patients. Finally, reviewing the scientific dimensions, history of psychiatric genetics is at the same time a walk through the history of complex genetics in general. In our review, we try to pay tribute to this complexity. We argue that psychiatric genetics has not only propelled our understanding of mental disorders but has significantly benefited genetic research into other complex disorders through the development of methodologically robust approaches (e.g., systematic phenotype characterisation, methods to control for ascertainment biases, age-correction). Given the recent reasons for new optimism, i.e., the identification of susceptibility genes for psychiatric phenotypes, a continued methodologically sound approach is needed more than ever to guarantee robust results. Finally, psychiatric genetic research should never again be performed in an environment void of ethical standards. PMID:16194759

Schulze, Thomas G; Fangerau, Heiner; Propping, Peter

2004-11-01

153

Genetic Analysis in Young-Age-of-Onset Graves' Disease Reveals New Susceptibility Loci.  

PubMed

Context: Genetic and environmental factors play an essential role in the pathogenesis of Graves' Disease (GD). Children with GD have less exposure time to environmental factors and therefore are believed to harbor stronger genetic susceptibility than adults. Objective: The aim of the study was to identify susceptibility loci that predispose to GD in patients with young-age-of-onset (YAO) GD. Setting and Design: One hundred six patients with YAO GD (onset <30 y) and 855 healthy subjects were studied. Cases and controls were genotyped using the Illumina Infinium Immunochip, designed to genotype 196,524 polymorphisms. Case control association analyses were performed using the PLINK computer package. Ingenuity Pathway Analysis program (QIAGEN) was used to carry out pathway analyses. Results: Immunochip genetic association analysis identified 30 single-nucleotide polymorphisms in several genes that were significantly associated with YAO GD, including major histocompatibility complex class I and class II genes, BTNL2, NOTCH4, TNFAIP3, and CXCR4. Candidate gene analysis revealed that most of the genes previously shown to be associated with adult-onset GD were also associated with YAO GD. Pathway analysis demonstrated that antigen presentation, T-helper cell differentiation, and B cell development were the major pathways contributing to the pathogenesis of YAO GD. Conclusions: Genetic analysis identified novel susceptibility loci in YAO GD adding a new dimension to the understanding of GD etiology. PMID:24684463

Brown, Rosalind S; Lombardi, Angela; Hasham, Alia; Greenberg, David A; Gordon, Joshua; Concepcion, Erlinda; Hammerstad, Sara S; Lotay, Vaneet; Zhang, Weijia; Tomer, Yaron

2014-07-01

154

Amphetamine-induced locomotion in a hyperdopaminergic ADHD mouse model depends on genetic background  

PubMed Central

We previously generated a knock-in mouse line with a cocaine-insensitive dopamine transporter (DAT-CI mice). These mice lost several behavioral responses to cocaine, but retained their response to amphetamine. DAT-CI mice are hyperdopaminergic due to reduced DAT function, and may thus be a good model for studying attention deficit hyperactivity disorder (ADHD). These mice had been behaviorally characterized while they were on a mixed genetic background. – However as the colony was propagated over time, the mixed genetics were shifted toward a pure C57Bl/6J background – via a common breeding scheme known as “backcrossing.” Several phenotypes appeared to have changed during this time frame. In this study, we investigated whether backcrossing altered the hyperlocomotive phenotype and behavioral responses to amphetamine, a drug used to treat ADHD. C57-congenic DAT-CI mice had high spontaneous locomotor activity that could be suppressed by low doses of amphetamine. Furthermore, their locomotion was not stimulated by very high doses of amphetamine (20 mg/kg). After the reversion to a mixed genetic background by breeding with the 129 strain, the C57:129 hybrid DAT-CI mice displayed reduced basal locomotor activity compared to the C57-congenic mutant mice, and regained locomotor stimulation by high-dose amphetamine. The calming effect of amphetamine at low doses was retained in both strains. In summary, reduced DAT function in DAT-CI mice leads to a hyperdopaminergic state, and an ADHD-like phenotype in both strains. The data show that the genetic background of DAT-CI mice affects their locomotor phenotypes and their responses to amphetamine. Since the differences in genetic background between the strains of mice have a significant impact on the ADHD-like phenotype and the response to amphetamine, further study with these strains could identify the genetic underpinnings affecting the severity of ADHD-related symptoms and the treatment response.

O'Neill, Brian; Gu, Howard H.

2012-01-01

155

Metabolomics of Apc Min/+ mice genetically susceptible to intestinal cancer  

PubMed Central

Background To determine how diets high in saturated fat could increase polyp formation in the mouse model of intestinal neoplasia, Apc Min/+ , we conducted large-scale metabolome analysis and association study of colon and small intestine polyp formation from plasma and liver samples of Apc Min/+ vs. wild-type littermates, kept on low vs. high-fat diet. Label-free mass spectrometry was used to quantify untargeted plasma and acyl-CoA liver compounds, respectively. Differences in contrasts of interest were analyzed statistically by unsupervised and supervised modeling approaches, namely Principal Component Analysis and Linear Model of analysis of variance. Correlation between plasma metabolite concentrations and polyp numbers was analyzed with a zero-inflated Generalized Linear Model. Results Plasma metabolome in parallel to promotion of tumor development comprises a clearly distinct profile in Apc Min/+ mice vs. wild type littermates, which is further altered by high-fat diet. Further, functional metabolomics pathway and network analyses in Apc Min/+ mice on high-fat diet revealed associations between polyp formation and plasma metabolic compounds including those involved in amino-acids metabolism as well as nicotinamide and hippuric acid metabolic pathways. Finally, we also show changes in liver acyl-CoA profiles, which may result from a combination of Apc Min/+ -mediated tumor progression and high fat diet. The biological significance of these findings is discussed in the context of intestinal cancer progression. Conclusions These studies show that high-throughput metabolomics combined with appropriate statistical modeling and large scale functional approaches can be used to monitor and infer changes and interactions in the metabolome and genome of the host under controlled experimental conditions. Further these studies demonstrate the impact of diet on metabolic pathways and its relation to intestinal cancer progression. Based on our results, metabolic signatures and metabolic pathways of polyposis and intestinal carcinoma have been identified, which may serve as useful targets for the development of therapeutic interventions.

2014-01-01

156

A high-density collection of EMS-induced mutations for TILLING in Landsberg erecta genetic background of Arabidopsis  

Microsoft Academic Search

BACKGROUND: Arabidopsis thaliana is the main model species for plant molecular genetics studies and world-wide efforts are devoted to identify the function of all its genes. To this end, reverse genetics by TILLING (Targeting Induced Local Lesions IN Genomes) in a permanent collection of chemically induced mutants is providing a unique resource in Columbia genetic background. In this work, we

Beatriz Martín; Mercedes Ramiro; José M Martínez-Zapater; Carlos Alonso-Blanco

2009-01-01

157

Genetic testing of newborns for type 1 diabetes susceptibility: a prospective cohort study on effects on maternal mental health  

PubMed Central

Background Concerns about the general psychological impact of genetic testing have been raised. In the Environmental Triggers of Type 1 Diabetes (MIDIA) study, genetic testing was performed for HLA-conferred type 1 diabetes susceptibility among Norwegian newborns. The present study assessed whether mothers of children who test positively suffer from poorer mental health and well-being after receiving genetic risk information about their children. Methods The study was based on questionnaire data from the Norwegian Mother and Child Cohort (MoBa) study conducted by the Norwegian Institute of Public Health. Many of the mothers in the MoBa study also took part in the MIDIA study, in which their newborn children were tested for HLA-conferred genetic susceptibility for type 1 diabetes. We used MoBa questionnaire data from the 30th week of pregnancy (baseline) and 6 months post-partum (3-3.5 months after disclosure of test results). We measured maternal symptoms of anxiety and depression (SCL-8), maternal self-esteem (RSES), and satisfaction with life (SWLS). The mothers also reported whether they were seriously worried about their child 6 months post-partum. We compared questionnaire data from mothers who had received information about having a newborn with high genetic risk for type 1 diabetes (N = 166) with data from mothers who were informed that their baby did not have a high-risk genotype (N = 7224). The association between genetic risk information and maternal mental health was analysed using multiple linear regression analysis, controlling for baseline mental health scores. Results Information on genetic risk in newborns was found to have no significant impact on maternal symptoms of anxiety and depression (p = 0.9), self-esteem (p = 0.2), satisfaction with life (p = 0.2), or serious worry about their child (OR = 0.98, 95% CI 0.64-1.48). Mental health before birth was strongly associated with mental health after birth. In addition, an increased risk of maternal worry was found if the mother herself had type 1 diabetes (OR = 2.39, 95% CI 1.2-4.78). Conclusions This study did not find evidence supporting the notion that genetic risk information about newborns has a negative impact on the mental health of Norwegian mothers.

2010-01-01

158

The value of animal models in predicting genetic susceptibility to complex diseases such as rheumatoid arthritis  

PubMed Central

For a long time, genetic studies of complex diseases were most successfully conducted in animal models. However, the field of genetics is now rapidly evolving, and human genetics has also started to produce strong candidate genes for complex diseases. This raises the question of how to continue gene-finding attempts in animals and how to use animal models to enhance our understanding of gene function. In this review we summarize the uses and advantages of animal studies in identification of disease susceptibility genes, focusing on rheumatoid arthritis. We are convinced that animal genetics will remain a valuable tool for the identification and investigation of pathways that lead to disease, well into the future.

Ahlqvist, Emma; Hultqvist, Malin; Holmdahl, Rikard

2009-01-01

159

Are Adolescents with ADHD Interested in Genetic Testing for Nicotine Addiction Susceptibility?  

PubMed Central

It has been well-established that some adolescents diagnosed with attention-deficit/hyperactivity disorder (ADHD) are at increased risk for cigarette smoking. Current research on the genetic basis of this association could ultimately translate into genetic tests capable of identifying smoking-prone adolescents with ADHD. In this study we examined 81 ADHD affected adolescents’ (age 13–21) interest in genetic testing for nicotine addiction susceptibility. Fifty-seven percent of adolescents indicated a fair amount of interest or more in testing. Most adolescents indicated that the personal information revealed from testing would be either useful (29%) or interesting (37%). Implications for genetically-informed smoking prevention and cessation interventions in high risk adolescents with ADHD are discussed.

Herbert, Linda J.; Walker, Leslie R.; Sharff, McKane E.; Abraham, Anisha A.; Tercyak, Kenneth P.

2010-01-01

160

The Jewish people: their ethnic history, genetic disorders and specific cancer susceptibility.  

PubMed

The Jews are an ancient and unique group of people linked by language, religion and customs in spite of their major geographical shifts, expulsions, forced conversions and massacres throughout their entire history. As a result of these historical events that led to repeated migration, the Jewish people became dispersed into various ethnic sub-groups. Between these ethnic groups exists heterogeneity, as well as some similarities, to the populations amongst whom they lived. Rare genetic diseases have been reported to be prevalent among the different groups of Jews, which for the most part can be explained by random genetic drift together with intra-familial marriages. In this publication, we will briefly discuss the origin of the various ethnic groups and some of the genetic diseases commonly found in them, with emphasis on the Ashkenazim, their prevalent genetic diseases and cancer susceptibility. PMID:15516841

Kedar-Barnes, Inbal; Rozen, Paul

2004-01-01

161

Selective sweep at a quantitative trait locus in the presence of background genetic variation.  

PubMed

We model selection at a locus affecting a quantitative trait (QTL) in the presence of genetic variance due to other loci. The dynamics at the QTL are related to the initial genotypic value and to the background genetic variance of the trait, assuming that background genetic values are normally distributed, under three different forms of selection on the trait. Approximate dynamics are derived under the assumption of small mutation effect. For similar strengths of selection on the trait (i.e, gradient of directional selection beta) the way background variation affects the dynamics at the QTL critically depends on the shape of the fitness function. It generally causes the strength of selection on the QTL to decrease with time. The resulting neutral heterozygosity pattern resembles that of a selective sweep with a constant selection coefficient corresponding to the early conditions. The signature of selection may also be blurred by mutation and recombination in the later part of the sweep. We also study the race between the QTL and its genetic background toward a new optimum and find the conditions for a complete sweep. Overall, our results suggest that phenotypic traits exhibiting clear-cut molecular signatures of selection may represent a biased subset of all adaptive traits. PMID:18832353

Chevin, Luis-Miguel; Hospital, Frédéric

2008-11-01

162

Functional analysis of heterologous holin proteins in a ??S genetic background  

Microsoft Academic Search

Holins are small hydrophobic proteins causing non-specific membrane lesions at the end of bacteriophage multiplication, to promote access of the murein hydrolase to their substrate. We have established a ??S genetic system, which enables functional expression of holins from various phages in an isogenic phage ? background, and allows qualitative evaluation of their ability to support lysis of Escherichia coli

Nataša Vukov; Siegfried Scherer; Edward Hibbert; Martin J. Loessner

2000-01-01

163

GENETIC BACKGROUND BUT NOT METALLOTHIONEIN PHENOTYPE DICTATES SENSITIVITY TO CADMIUM-INDUCED TESTICULAR INJURY IN MICE  

EPA Science Inventory

Genetic Background but not Metallothionein Phenotype Dictates Sensitivity to Cadmium-Induced Testicular Injury in Mice Jie Liu1,2, Chris Corton3, David J. Dix4, Yaping Liu1, Michael P. Waalkes2 and Curtis D. Klaassen1 ABSTRACT Parenteral administrati...

164

A candidate gene approach for the genetic analysis of susceptibility to tuberculosis  

SciTech Connect

Tuberculosis is the most frequent and severe human disease caused by mycobacteria. In the mouse a candidate gene for innate resistance to mycobacteria (Bcg) was recently isolated and termed Nramp. We used SSCA and DNA sequencing to identify mutations in the human homologue, NRAMP, in chromosome region 2q35 in order to test if NRAMP contributes to susceptibility to tuberculosis. We have identified 16 sequence variants in or near NRAMP and defined haplotypes segregating in multiplex tuberculosis families from Canada, Columbia and Hong Kong. We defined a recessive susceptibility model for linkage analysis with four liability classes which take into account clinical status, age, exposure, and BCG vaccination. Our preliminary results support a role of NRAMP in tuberculosis susceptibility in an epidemic situation. This research was supported by grants from the Medical Research Council of Canada and the Canadian Genetic Diseases Network.

Morgan, K.; Liu, J.; Boothroyd, L. [McGill Univ., Quebec (Canada)] [and others

1994-09-01

165

Genetic markers of disease susceptibility and severity in giant cell arteritis and polymyalgia rheumatica  

Microsoft Academic Search

Background and Objectives: Giant cell arteritis (GCA) and polymyalgia rheumatica (PMR) are common and often overlapping diseases that generally occur in elderly patients. In this article, we examine the role of different genes as markers of disease susceptibility and severity in GCA and PMR. Methods: The influence of human leukocyte antigen (HLA)-DRB1 and tumor necrosis factor alleles, as well as

Miguel A. González-Gay; Mahsa M. Amoli; Carlos Garcia-Porrua; William E. R. Ollier

2003-01-01

166

A Significant Factor in Autism: Methyl Mercury Induced Oxidative Stress in Genetically Susceptible Individuals  

Microsoft Academic Search

The dramatic increase in prevalence rates of Autism Spectrum Disorders (ASDs) over recent decades likely reflects the influence\\u000a of multiple factors. In the current paper, it is argued ASDs can result from an interaction between genetic susceptibilities\\u000a and environmental exposures. Specifically, we hypothesize that fetal or infantile exposure to methyl mercury containing pollution\\u000a by individuals with biologically inhibited antioxidant functions

Kerry E. Leslie; Susan M. Koger

167

EXPERIMENTAL INDUCTION OF CHRONIC PULMONARY DISEASE IN GENETICALLY SUSCEPTIBLE RAT MODEL  

EPA Science Inventory

Experimental induction of chronic pulmonary disease in genetically susceptible rat model. M.C.Schladweiler, BS 1, A.D.Ledbetter 1, K.E.Pinkerton, PhD 2, K.R.Smith, PhD 2, P.S.Gilmour, PhD 1, P.A.Evansky 1, D.L.Costa, ScD 1, W.P.Watkinson, PhD 1, J.P.Nolan 1 and U.P.Kodava...

168

Young smokers’ views of genetic susceptibility testing for lung cancer risk: minding unintended consequences  

Microsoft Academic Search

Assessment of smokers’ responses to individualized feedback of genetic susceptibility has shown little or no influence on\\u000a smoking cessation outcomes. One explanation is that smokers may be having unintended responses that undermine the feedback’s\\u000a motivational impact (e.g., fatalism or downplaying risk). In preparation for a large randomized trial with college smokers,\\u000a we conducted a qualitative pilot study to explore smokers’

Sharron L. Docherty; Colleen M. McBride; Saskia C. Sanderson; Suzanne C. O’Neill; James A. Shepperd; Isaac M. Lipkus

2011-01-01

169

Genetic variants associated with idiopathic pulmonary fibrosis susceptibility and mortality: a genome-wide association study  

PubMed Central

Summary Background Idiopathic pulmonary fibrosis (IPF) is a devastating disease that probably involves several genetic loci. Several rare genetic variants and one common single nucleotide polymorphism (SNP) of MUC5B have been associated with the disease. Our aim was to identify additional common variants associated with susceptibility and ultimately mortality in IPF. Methods First, we did a three-stage genome-wide association study (GWAS): stage one was a discovery GWAS; and stages two and three were independent case-control studies. DNA samples from European-American patients with IPF meeting standard criteria were obtained from several US centres for each stage. Data for European-American control individuals for stage one were gathered from the database of genotypes and phenotypes; additional control individuals were recruited at the University of Pittsburgh to increase the number. For controls in stages two and three, we gathered data for additional sex-matched European-American control individuals who had been recruited in another study. DNA samples from patients and from control individuals were genotyped to identify SNPs associated with IPF. SNPs identified in stage one were carried forward to stage two, and those that achieved genome-wide significance (p<5 × 10?8) in a meta-analysis were carried forward to stage three. Three case series with follow-up data were selected from stages one and two of the GWAS using samples with follow-up data. Mortality analyses were done in these case series to assess the SNPs associated with IPF that had achieved genome-wide significance in the meta-analysis of stages one and two. Finally, we obtained gene-expression profiling data for lungs of patients with IPF from the Lung Genomics Research Consortium and analysed correlation with SNP genotypes. Findings In stage one of the GWAS (542 patients with IPF, 542 control individuals matched one-by-one to cases by genetic ancestry estimates), we identified 20 loci. Six SNPs reached genome-wide significance in stage two (544 patients, 687 control individuals): three TOLLIP SNPs (rs111521887, rs5743894, rs5743890) and one MUC5B SNP (rs35705950) at 11p15.5; one MDGA2 SNP (rs7144383) at 14q21.3; and one SPPL2C SNP (rs17690703) at 17q21.31. Stage three (324 patients, 702 control individuals) confirmed the associations for all these SNPs, except for rs7144383. Linkage disequilibrium between the MUC5B SNP (rs35705950) and TOLLIP SNPs (rs111521887 [r2=0.07], rs5743894 [r2=0.16], and rs5743890 [r2=0.01]) was low. 683 patients from the GWAS were included in the mortality analysis. Individuals who developed IPF despite having the protective TOLLIP minor allele of rs5743890 carried an increased mortality risk (meta-analysis with fixed-effect model: hazard ratio 1.72 [95% CI 1.24–2.38]; p=0.0012). TOLLIP expression was decreased by 20% in individuals carrying the minor allele of rs5743890 (p=0.097), 40% in those with the minor allele of rs111521887 (p=3.0 × 10?4), and 50% in those with the minor allele of rs5743894 (p=2.93 × 10?5) compared with homozygous carriers of common alleles for these SNPs. Interpretation Novel variants in TOLLIP and SPPL2C are associated with IPF susceptibility. One novel variant of TOLLIP, rs5743890, is also associated with mortality. These associations and the reduced expression of TOLLIP in patients with IPF who carry TOLLIP SNPs emphasise the importance of this gene in the disease. Funding National Institutes of Health; National Heart, Lung, and Blood Institute; Pulmonary Fibrosis Foundation; Coalition for Pulmonary Fibrosis; and Instituto de Salud Carlos III.

Flores, Carlos; Barber, Mathew; Huang, Yong; Broderick, Steven M; Wade, Michael S; Hysi, Pirro; Scuirba, Joseph; Richards, Thomas J; Juan-Guardela, Brenda M; Vij, Rekha; Han, MeiLan K; Martinez, Fernando J; Kossen, Karl; Seiwert, Scott D; Christie, Jason D

2013-01-01

170

CTLA4 Variants and Haplotype Contribute Genetic Susceptibility to Myasthenia Gravis in Northern Chinese Population  

PubMed Central

Background Cytotoxic T lymphocyte-associated antigen-4 (CTLA4), a critical negative regulator of the T-cell response, has been considered a candidate for many autoimmune diseases. Evidence from Caucasians supported a genetic predisposition of CTLA4 to myasthenia gravis (MG), but the contribution in East Asians has not been established. Objectives To investigate the role of CTLA4 variants in the susceptibility to MG and the contribution to subtypes of MG. Methods Six autoimmune disease-related risk alleles of CTLA4 (rs1863800, rs733618, rs4553808, rs5742909, rs231775, and rs3087243) were investigated for MG in northern Chinese. 168 patients with MG (mean age 37.1±20.5 years, 64 men and 104 women) and 233 healthy controls (mean age 53.3±8.7 years, 96 men and 137 women) were screened, and the contribution of CTLA4 to the general risk of MG and each subgroup was explored. Results rs1863800*C, rs733618*C, and rs231775*G were significantly associated with the whole cohort of patients with MG after permutation correction for multiple-testing adjustment (P?=?0.027, 0.001, and 0.032, respectively). A risk haplotype (CCACG) [odds ratio (OR)?=?1.535, range?=?1.150–2.059, P?=?0.004)] was also identified. The stratified subtype analysis indicated that the positive contribution was possibly derived from early onset MG (EOMG), seropositive MG (SPMG), female patients, and MG without thymoma. No association was observed in juvenile MG/LOMG, and MG coupled with thymoma. Conclusion A predisposing effect of rs1863800*C, rs733618*C, and rs231775*G of CTLA4 gene to general risk of MG in Chinese was demonstrated for the first time, which was likely derived from EOMG, SPMG, MG without thymoma and the female patients.

Xie, Yanchen; Zhang, Hua; Zhang, Zheng; Wang, Xiaoxia; Jiang, Bin; Li, Wei; Li, Yao; Yang, Ze

2014-01-01

171

The Impact of Genetic Susceptibility to Systemic Lupus Erythematosus on Placental Malaria in Mice  

PubMed Central

Severe malaria, including cerebral malaria (CM) and placental malaria (PM), have been recognized to have many of the features of uncontrolled inflammation. We recently showed that in mice genetic susceptibility to the lethal inflammatory autoimmune disease, systemic lupus erythematosus (SLE), conferred resistance to CM. Protection appeared to be mediated by immune mechanisms that allowed SLE-prone mice, prior to the onset of overt SLE symptoms, to better control their inflammatory response to Plasmodium infection. Here we extend these findings to ask does SLE susceptibility have 1) a cost to reproductive fitness and/or 2) an effect on PM in mice? The rates of conception for WT and SLE susceptible (SLEs) mice were similar as were the number and viability of fetuses in pregnant WT and SLEs mice indicating that SLE susceptibility does not have a reproductive cost. We found that Plasmodium chabaudi AS (Pc) infection disrupted early stages of pregnancy before the placenta was completely formed resulting in massive decidual necrosis 8 days after conception. Pc-infected pregnant SLEs mice had significantly more fetuses (?1.8 fold) but SLE did not significantly affect fetal viability in infected animals. This was despite the fact that Pc-infected pregnant SLEs mice had more severe symptoms of malaria as compared to Pc-infected pregnant WT mice. Thus, although SLE susceptibility was not protective in PM in mice it also did not have a negative impact on reproductive fitness.

Waisberg, Michael; Lin, Christina K.; Huang, Chiung-Yu; Pena, Mirna; Orandle, Marlene; Bolland, Silvia; Pierce, Susan K.

2013-01-01

172

Cellular basis of the genetic susceptibility of murine experimental allergic encephalomyelitis  

SciTech Connect

Murine experimental allergic encephalomyelitis (EAE) is an induced autoimmune disease that resembles human multiple sclerosis. The authors have investigated the cellular basis of the genetic predisposition and resistance of inbred strains of mice to EAE using an adoptive transfer system between two H-2 compatible, Thy 1 antigen disparate strains of mice. Genetically EAE susceptible SJL/J strain mice (H-2/sup s/, Thy 1.2) and resistant B10.S Thy 1.1 (H-2/sub s/, Thy 1.1) strain mice were lethally irradiated (700R) and reconstituted with 5-10 x 10/sup 6/ bone marrow cells from either SJL/J or congenic B10.S (Thy 1.1 or Thy 1.2) donors. After 30-45 days, more than 95% of the thymocytes and 75% of the peripheral T cells in the chimeras were of donor origin. These lymphohemopoietic chimeras were then sensitized in their hind footpads with porcine myelin basic protein in complete Freund's adjuvant containing M. tuberculosis H/sub 37/RA, followed at 24 and 72 hours by i.v. injection of B. pertussis. Clinical signs of EAE developed in unirradiated SJL/J, but not B10.S, controls, and in irradiated B10.S and SJL/J recipients of SJL/J, but not B10.S, bone marrow. These results indicate that bone marrow cells can transfer the predisposition to EAE from genetically susceptible to genetically resistant mouse strains. The cellular component in the bone marrow that is responsible for the transfer of the genetic susceptibility to EAE is under investigation.

Binder, T.A.; Greiner, D.L.; Goldschneider, I.

1986-03-01

173

Genetic Structure Adds Power to Detect Schizophrenia Susceptibility at SLIT3 in the Chinese Han Population  

PubMed Central

The Chinese Han population, the largest population in the world, has traditionally been geographically divided into two parts, the Southern Han and Northern Han. In practice, however, these commonly used ethnic labels are both insufficient and inaccurate as descriptors of inferred genetic clustering, and can lead to the observation of “spurious association” as well as the concealment of real association. In this study, we attempted to address this problem by using 14 microsatellite markers to reconstruct the population genetic structure in 768 Han Chinese samples, including 384 Southern Han and 384 Northern Han, and in samples from Chinese minorities including 48 Yao and 48 BouYei subjects. Furthermore, with a dense set of markers around the region 5q34–35, we built fine-scale haplotype networks for each population/subpopulation and tested for association to schizophrenia susceptibility. We found that more variants in SLIT3 tend to associate with schizophrenia susceptibility in the genetically structured samples, compared to geographically structured samples and samples without identified population substructure. Our results imply that identifying the hidden genetic substructure adds power when detecting association, and suggest that SLIT3 or a nearby gene is associated with schizophrenia.

Shi, YongYong; Zhao, XinZhi; Yu, Lan; Tao, Ran; Tang, JunXia; La, YuJuan; Duan, Yun; Gao, Bo; Gu, NiuFan; Xu, YiFeng; Feng, GuoYin; Zhu, ShaoMin; Liu, HuiJun; Salter, Hugh; He, Lin

2004-01-01

174

CHEMICALLY AND GENETICALLY IMMUNOCOMPROMISED MICE ARE NOT MORE SUSCEPTIBLE THAN IMMUNOCOMPETENT MICE TO INFECTION WITH CRYPTOSPORIDIUM MURIS  

EPA Science Inventory

The prevailing paradigm is that immunosuppressed individuals are more susceptible to infection and are at higher risk of infection from Cryptosporidium oocysts if present in drinking water. To test this hypothesis, three immune conditions were examined: genetically immunocomprom...

175

Distorted Mendelian transmission as a function of genetic background in Rai1-haploinsufficient mice.  

PubMed

The retinoic acid induced 1 gene (RAI1) is the primary causative gene for Smith-Magenis syndrome (SMS). Chromosomal deletion encompassing RAI1 or mutation in RAI1 is responsible for the majority of SMS features. Mouse models with targeted disruption of Rai1 have recapitulated overt SMS phenotypes, including craniofacial abnormalities, obesity, and neurobehavioral anomalies. Penetrance and expressivity of most phenotypes in mice were incomplete due to the mixed genetic background in which they were created. While increased penetrance of craniofacial phenotypes was observed in relatively homogeneous backgrounds, the effect of Rai1 haploinsufficiency on breeding outcome and fitness has not been studied. We analyzed mating results of Rai1+/- mice in a pure C57BL/6J background (>or=N10 generations). A significant distortion (P<0.05) of Mendelian transmission ratio with skewing against Rai1+/- mice was observed. Consequently, a decreased number of Rai1+/- pups and no Rai1-/- pups were obtained from all the breeding pairs. The decreased yield of Rai1+/- pups precluded penetrance studies of other phenotypes in these mice. However, when Rai1+/- alleles were transferred to a slightly variable (approximately 1% 129/approximately 99% C57BL/6J) genetic background expected numbers of Rai1+/- pups were obtained. Our results indicate that selection against Rai1-haploinsufficient alleles is governed primarily by modifier genes. Our data show that genetic background or modifier genes also significantly contribute to the severity of the phenotypes in SMS mouse models, mirroring the phenotypic variation observed in humans with Smith-Magenis syndrome and support the need for investigation of modifier loci for both single gene and complex genetic syndromes. PMID:19116176

Girirajan, Santhosh; Elsea, Sarah H

2009-01-01

176

Anopheles gambiae pathogen susceptibility: the intersection of genetics, immunity and ecology.  

PubMed

Mosquitoes are the major arthropod vectors of human diseases such as malaria and viral encephalitis. However, each mosquito species does not transmit every pathogen, owing to reasons that include specific evolutionary histories, mosquito immune system structure, and ecology. Even a competent vector species for a pathogen displays a wide range of variation between individuals for pathogen susceptibility, and therefore efficiency of disease transmission. Understanding the molecular and genetic mechanisms that determine heterogeneities in transmission efficiency within a vector species could help elaborate new vector control strategies. This review discusses mechanisms of host-defense in Anopheles gambiae, and sources of genetic and ecological variation in the operation of these protective factors. Comparison is made between functional studies using Plasmodium or fungus, and we call attention to the limitations of generalizing gene phenotypes from experiments done in a single genetically simple colony. PMID:22538050

Mitri, Christian; Vernick, Kenneth D

2012-06-01

177

Anopheles gambiae pathogen susceptibility: The intersection of genetics, immunity and ecology  

PubMed Central

Mosquitoes are the major arthropod vectors of human diseases such as malaria and viral encephalitis. However, each mosquito species does not transmit every pathogen, due to reasons that include specific evolutionary histories, mosquito immune system structure, and ecology. Even a competent vector species for a pathogen displays a wide range of variation between individuals for pathogen susceptibility, and therefore efficiency of disease transmission. Understanding the molecular and genetic mechanisms that determine heterogeneities in transmission efficiency within a vector species could help elaborate new vector control strategies. This review discusses mechanisms of host-defense in Anopheles gambiae, and sources of genetic and ecological variation in the operation of these protective factors. Comparison is made between functional studies using Plasmodium or fungus, and we call attention to the limitations of generalizing gene phenotypes from experiments done in a single genetically simple colony.

Mitri, Christian; Vernick, Kenneth D.

2012-01-01

178

Phlebotomus orientalis Sand Flies from Two Geographically Distant Ethiopian Localities: Biology, Genetic Analyses and Susceptibility to Leishmania donovani  

PubMed Central

Background Phlebotomus orientalis Parrot (Diptera: Psychodidae) is the main vector of visceral leishmaniasis (VL) caused by Leishmania donovani in East Africa. Here we report on life cycle parameters and susceptibility to L. donovani of two P. orientalis colonies originating from different sites in Ethiopia: a non-endemic site in the lowlands - Melka Werer (MW), and an endemic focus of human VL in the highlands - Addis Zemen (AZ). Methodology/Principal Findings Marked differences in life-cycle parameters between the two colonies included distinct requirements for larval food and humidity during pupation. However, analyses using Random Amplified Polymorphic DNA (RAPD) PCR and DNA sequencing of cytB and COI mitochondrial genes did not reveal any genetic differences. F1 hybrids developed successfully with higher fecundity than the parental colonies. Susceptibility of P. orientalis to L. donovani was studied by experimental infections. Even the lowest infective dose tested (2×103 per ml) was sufficient for successful establishment of L. donovani infections in about 50% of the P. orientalis females. Using higher infective doses, the infection rates were around 90% for both colonies. Leishmania development in P. orientalis was fast, the presence of metacyclic promastigotes in the thoracic midgut and the colonization of the stomodeal valve by haptomonads were recorded in most P. orientalis females by day five post-blood feeding. Conclusions Both MW and AZ colonies of P. orientalis were highly susceptible to Ethiopian L. donovani strains. As the average volume of blood-meals taken by P. orientalis females are about 0.7 µl, the infective dose at the lowest concentration was one or two L. donovani promastigotes per sand fly blood-meal. The development of L. donovani was similar in both P. orientalis colonies; hence, the absence of visceral leishmaniasis in non-endemic area Melka Werer cannot be attributed to different susceptibility of local P. orientalis populations to L. donovani.

Seblova, Veronika; Volfova, Vera; Dvorak, Vit; Pruzinova, Katerina; Votypka, Jan; Kassahun, Aysheshm; Gebre-Michael, Teshome; Hailu, Asrat; Warburg, Alon; Volf, Petr

2013-01-01

179

Case-control study for colorectal cancer genetic susceptibility in EPICOLON: previously identified variants and mucins  

PubMed Central

Background Colorectal cancer (CRC) is the second leading cause of cancer death in developed countries. Familial aggregation in CRC is also important outside syndromic forms and, in this case, a polygenic model with several common low-penetrance alleles contributing to CRC genetic predisposition could be hypothesized. Mucins and GALNTs (N-acetylgalactosaminyltransferase) are interesting candidates for CRC genetic susceptibility and have not been previously evaluated. We present results for ten genetic variants linked to CRC risk in previous studies (previously identified category) and 18 selected variants from the mucin gene family in a case-control association study from the Spanish EPICOLON consortium. Methods CRC cases and matched controls were from EPICOLON, a prospective, multicenter, nationwide Spanish initiative, comprised of two independent stages. Stage 1 corresponded to 515 CRC cases and 515 controls, whereas stage 2 consisted of 901 CRC cases and 909 controls. Also, an independent cohort of 549 CRC cases and 599 controls outside EPICOLON was available for additional replication. Genotyping was performed for ten previously identified SNPs in ADH1C, APC, CCDN1, IL6, IL8, IRS1, MTHFR, PPARG, VDR and ARL11, and 18 selected variants in the mucin gene family. Results None of the 28 SNPs analyzed in our study was found to be associated with CRC risk. Although four SNPs were significant with a P-value < 0.05 in EPICOLON stage 1 [rs698 in ADH1C (OR = 1.63, 95% CI = 1.06-2.50, P-value = 0.02, recessive), rs1800795 in IL6 (OR = 1.62, 95% CI = 1.10-2.37, P-value = 0.01, recessive), rs3803185 in ARL11 (OR = 1.58, 95% CI = 1.17-2.15, P-value = 0.007, codominant), and rs2102302 in GALNTL2 (OR = 1.20, 95% CI = 1.00-1.44, P-value = 0.04, log-additive 0, 1, 2 alleles], only rs3803185 achieved statistical significance in EPICOLON stage 2 (OR = 1.34, 95% CI = 1.06-1.69, P-value = 0.01, recessive). In the joint analysis for both stages, results were only significant for rs3803185 (OR = 1.12, 95% CI = 1.00-1.25, P-value = 0.04, log-additive 0, 1, 2 alleles) and borderline significant for rs698 and rs2102302. The rs3803185 variant was not significantly associated with CRC risk in an external cohort (MCC-Spain), but it still showed some borderline significance in the pooled analysis of both cohorts (OR = 1.08, 95% CI = 0.98-1.18, P-value = 0.09, log-additive 0, 1, 2 alleles). Conclusions ARL11, ADH1C, GALNTL2 and IL6 genetic variants may have an effect on CRC risk. Further validation and meta-analyses should be undertaken in larger CRC studies.

2011-01-01

180

A cellular perspective on conformational disease: The role of genetic background and proteostasis networks  

PubMed Central

Summary The inherently error-prone nature of protein biosynthesis and turnover leads to a constant flux of destabilized proteins. Genetic mutations in conformational disease-associated proteins, as well as exposure to acute and chronic proteotoxic stresses, further increase the load of misfolded protein on the proteostasis network. During aging, this leads to enhanced instability of the proteome, failure to buffer destabilizing genetic mutations or polymorphisms, and cellular decline. The combination of cell-type-specific differences in the buffering capacity of the proteostasis network and destabilizing polymorphisms in the genetic background may account for some of the cell-type specificity observed in disease, even when the predominant disease-associated protein is widely expressed.

Gidalevitz, Tali; Kikis, Elise A.; Morimoto, Richard I.

2010-01-01

181

Genetics and Beyond - The Transcriptome of Human Monocytes and Disease Susceptibility  

Microsoft Academic Search

BackgroundVariability of gene expression in human may link gene sequence variability and phenotypes; however, non-genetic variations, alone or in combination with genetics, may also influence expression traits and have a critical role in physiological and disease processes.Methodology\\/Principal FindingsTo get better insight into the overall variability of gene expression, we assessed the transcriptome of circulating monocytes, a key cell involved in

Tanja Zeller; Philipp Wild; Silke Szymczak; Maxime Rotival; Arne Schillert; Raphaele Castagne; Seraya Maouche; Marine Germain; Karl Lackner; Heidi Rossmann; Medea Eleftheriadis; Christoph R. Sinning; Renate B. Schnabel; Edith Lubos; Detlev Mennerich; Werner Rust; Claire Perret; Carole Proust; Viviane Nicaud; Joseph Loscalzo; Norbert Hübner; David Tregouet; Thomas Münzel; Andreas Ziegler; Laurence Tiret; Stefan Blankenberg; François Cambien; Zoltán Bochdanovits

2010-01-01

182

Destabilizing protein polymorphisms in the genetic background direct phenotypic expression of mutant SOD1 toxicity.  

PubMed

Genetic background exerts a strong modulatory effect on the toxicity of aggregation-prone proteins in conformational diseases. In addition to influencing the misfolding and aggregation behavior of the mutant proteins, polymorphisms in putative modifier genes may affect the molecular processes leading to the disease phenotype. Mutations in SOD1 in a subset of familial amyotrophic lateral sclerosis (ALS) cases confer dominant but clinically variable toxicity, thought to be mediated by misfolding and aggregation of mutant SOD1 protein. While the mechanism of toxicity remains unknown, both the nature of the SOD1 mutation and the genetic background in which it is expressed appear important. To address this, we established a Caenorhabditis elegans model to systematically examine the aggregation behavior and genetic interactions of mutant forms of SOD1. Expression of three structurally distinct SOD1 mutants in C. elegans muscle cells resulted in the appearance of heterogeneous populations of aggregates and was associated with only mild cellular dysfunction. However, introduction of destabilizing temperature-sensitive mutations into the genetic background strongly enhanced the toxicity of SOD1 mutants, resulting in exposure of several deleterious phenotypes at permissive conditions in a manner dependent on the specific SOD1 mutation. The nature of the observed phenotype was dependent on the temperature-sensitive mutation present, while its penetrance reflected the specific combination of temperature-sensitive and SOD1 mutations. Thus, the specific toxic phenotypes of conformational disease may not be simply due to misfolding/aggregation toxicity of the causative mutant proteins, but may be defined by their genetic interactions with cellular pathways harboring mildly destabilizing missense alleles. PMID:19266020

Gidalevitz, Tali; Krupinski, Thomas; Garcia, Susana; Morimoto, Richard I

2009-03-01

183

THE MITOCHONDRIAL PARADIGM FOR CARDIOVASCULAR DISEASE SUSCEPTIBILITY AND CELLULAR FUNCTION: A COMPLEMENTARY CONCEPT TO MENDELIAN GENETICS  

PubMed Central

While there is general agreement that cardiovascular disease (CVD) development is influenced by a combination of genetic, environmental, and behavioral contributors, the actual mechanistic basis of how these factors initiate or promote CVD development in some individuals while others with identical risk profiles do not, is not clearly understood. This review considers the potential role for mitochondrial genetics and function in determining CVD susceptibility from the standpoint that the original features that molded cellular function were based upon mitochondrial-nuclear relationships established millions of years ago and were likely refined during prehistoric environmental selection events that today, are largely absent. Consequently, contemporary risk factors that influence our susceptibility to a variety of age-related diseases, including CVD were probably not part of the dynamics that defined the processes of mitochondrial – nuclear interaction, and thus, cell function. In this regard, the selective conditions that contributed to cellular functionality and evolution should be given more consideration when interpreting and designing experimental data and strategies. Finally, future studies that probe beyond epidemiologic associations are required. These studies will serve as the initial steps for addressing the provocative concept that contemporary human disease susceptibility is the result of selection events for mitochondrial function that increased chances for prehistoric human survival and reproductive success.

Kryzwanski, David M.; Moellering, Douglas; Fetterman, Jessica L.; Dunham-Snary, Kimberly J.; Sammy, Melissa J.; Ballinger, Scott W.

2013-01-01

184

Genetic background impacts soluble and cell wall-bound aromatics in brown midrib mutants of sorghum  

Microsoft Academic Search

Sorghum (Sorghum bicolor (L.). Moench) BMR-6 and BMR-12 encode cinnamylalcohol dehydrogenase and caffeic acid-O-methyltransferase, respectively. We have evaluated the impact of two bmr alleles, bmr-6 and bmr-12, respectively, on soluble and wall-bound aromatics in near isogenic, wild-type (WT), bmr-6, bmr-12 and double-mutant (DM; bmr-6 and bmr-12) plants in two genetic backgrounds, RTx430 and Wheatland. Immunoblots confirmed that COMT protein was

Nathan A. Palmer; Scott E. Sattler; Aaron J. Saathoff; Deanna Funnell; Jeffery F. Pedersen; Gautam Sarath

2008-01-01

185

Identification of Genetic Susceptibility to Childhood Cancer through Analysis of Genes in Parallel  

PubMed Central

Clinical cancer genetic susceptibility analysis typically proceeds sequentially beginning with the most likely causative gene. The process is time consuming and the yield is low particularly for families with unusual patterns of cancer. We determined the results of in parallel mutation analysis of a large cancer-associated gene panel. We performed deletion analysis and sequenced the coding regions of 45 genes (8 oncogenes and 37 tumor suppressor or DNA repair genes) in 48 childhood cancer patients who also (1) were diagnosed with a second malignancy under age 30, (2) have a sibling diagnosed with cancer under age 30 and/or (3) have a major congenital anomaly or developmental delay. Deleterious mutations were identified in 6 of 48 (13%) families, 4 of which met the sibling criteria. Mutations were identified in genes previously implicated in both dominant and recessive childhood syndromes including SMARCB1, PMS2, and TP53. No pathogenic deletions were identified. This approach has provided efficient identification of childhood cancer susceptibility mutations and will have greater utility as additional cancer susceptibility genes are identified. Integrating parallel analysis of large gene panels into clinical testing will speed results and increase diagnostic yield. The failure to detect mutations in 87% of families highlights that a number of childhood cancer susceptibility genes remain to be discovered.

Plon, Sharon E.; Wheeler, David A.; Strong, Louise C.; Tomlinson, Gail E.; Pirics, Michael; Meng, Qingchang; Cheung, Hannah C.; Begin, Phyllis R.; Muzny, Donna M.; Lewis, Lora; Biegel, Jaclyn A.; Gibbs, Richard A.

2011-01-01

186

Genetic susceptibility to tuberculosis associated with cathepsin Z haplotype in a Ugandan household contact study.  

PubMed

Tuberculosis (TB), caused by Mycobacterium tuberculosis (Mtb), causes 9 million new cases worldwide and 2 million deaths annually. Genetic linkage and association analyses have suggested several chromosomal regions and candidate genes involved in TB susceptibility. This study examines the association of TB disease susceptibility with a selection of biologically relevant genes on regions on chromosomes 7 (IL6 and CARD11) and 20 (CTSZ and MC3R) and fine mapping of the chromosome 7p22-p21 region identified through our genome scan. We analyzed 565 individuals from Kampala, Uganda, who were previously included in our genome-wide linkage scan. Association analyses were conducted for 1,417 single-nucleotide polymorphisms (SNP) that passed quality control. None of the candidate gene or fine mapping SNPs was significantly associated with TB susceptibility (p > 0.10). When we restricted the analysis to HIV-negative individuals, 2 SNPs on chromosome 7 were significantly associated with TB susceptibility (p < 0.05). Haplotype analyses identified a significant risk haplotype in cathepsin X (CTSZ; p = 0.0281, odds ratio = 1.5493, 95% confidence interval [1.039, 2.320]). PMID:21354459

Baker, Allison R; Zalwango, Sarah; Malone, LaShaunda L; Igo, Robert P; Qiu, Feiyou; Nsereko, Mary; Adams, Mark D; Supelak, Pamela; Mayanja-Kizza, Harriet; Boom, W Henry; Stein, Catherine M

2011-05-01

187

Relative susceptibilities of male germ cells to genetic defects induced by cancer chemotherapies  

SciTech Connect

Some chemotherapy regimens include agents that are mutagenic or clastogenic in model systems. This raises concerns that cancer survivors, who were treated before or during their reproductive years, may be at increased risks for abnormal reproductive outcomes. However, the available data from offspring of cancer survivors are limited, representing diverse cancers, therapies, time-to-pregnancies, and reproductive outcomes. Rodent breeding data after paternal exposures to individual chemotherapeutic agents illustrate the complexity of factors that influence the risk for transmitted genetic damage including agent, dose, endpoint, and the germ-cell susceptibility profiles that vary across agents. Direct measurements of chromosomal abnormalities in sperm of mice and humans by sperm FISH have corroborated the differences in germ-cell susceptibilities. The available evidence suggests that the risk of producing chromosomally defective sperm is highest during the first few weeks after the end of chemotherapy, and decays with time. Thus, sperm samples provided immediately after the initiation of cancer therapies may contain treatment-induced genetic defects that will jeopardize the genetic health of offspring.

Wyrobek, A J; Schmid, T E; Marchetti, F

2004-06-15

188

APECED: A Paradigm of Complex Interactions between Genetic Background and Susceptibility Factors  

PubMed Central

Autoimmune polyendocrinopathy-candidiasis-ectodermal dystrophy (APECED) is a rare autosomal recessive disease, caused by mutations of a single gene named Autoimmune regulator gene (AIRE) which results in a failure of T-cell tolerance. Central tolerance takes place within the thymus and represents the mechanism by which potentially auto-reactive T-cells are eliminated through the negative selection process. The expression of tissue-specific antigens (TSAs) by medullary thymic epithelial cells (mTECs) in the thymus is a key process in the central tolerance and is driven by the protein encoded by AIRE gene, the transcription factor autoimmune regulator (AIRE). A failure in this process caused by AIRE mutations is thought to be responsible of the systemic autoimmune reactions of APECED. APECED is characterized by several autoimmune endocrine and non-endocrine manifestations and the phenotype is often complex. Although APECED is the paradigm of a monogenic autoimmune disorder, it is characterized by a wide variability of the clinical expression even between siblings with the same genotype, thus implying that additional mechanisms, other than the failure of Aire function, are involved in the pathogenesis of the disease. Unraveling open issues of the molecular basis of APECED, will help improve diagnosis, management, and therapeutical strategies of this complex disease.

De Martino, Lucia; Capalbo, Donatella; Improda, Nicola; D'Elia, Federica; Di Mase, Raffaella; D'Assante, Roberta; D'Acunzo, Ida; Pignata, Claudio; Salerno, Mariacarolina

2013-01-01

189

Molecular genetic analysis of the cytochrome P450-debrisoquine hydroxylase locus and association with cancer susceptibility.  

PubMed Central

The cytochrome P450-dependent monooxygenases play a central role in the metabolism of chemical carcinogens. The action of these enzymes can lead to either carcinogen detoxication or activation. Differences in P450 expression in animal models give rise to large differences in susceptibility to chemical carcinogens, so genetic polymorphisms in P450 expression may be expected to be an important factor in individual human susceptibility to cancer. Of particular interest is the genetic polymorphism at the cytochrome P450-debrisoquine/sparteine hydroxylase locus (CYP2D6). Although this is a minor liver P450, its polymorphic expression is associated with the abnormal metabolism of at least 30 therapeutic drugs, including beta-blockers and tricyclic antidepressants. Conflicting reports have been made on the association of this polymorphism with cancer susceptibility. This disagreement may be attributable to limitations of the phenotyping assay used to identify affected individuals (poor metabolizers, PMs). In order to clarify these anomalies, we have developed a simple DNA-based assay with which we can identify the majority of PMs. The assay is centered around the primary gene defect responsible for the polymorphism, a G to A transition at the junction of intron 3/exon 4 which results in a frame-shift in the resultant mRNA. The frequency of this mutation is 70-80% in PMs. We have studied the frequency of mutated alleles in a control population and in a wide range of cancer patients. No association between this polymorphism and lung cancer susceptibility was observed; however, in other populations of cancer patients some very interesting shifts were found in the proportion of PMs and heterozygotes from that in the normal population.

Smith, C A; Moss, J E; Gough, A C; Spurr, N K; Wolf, C R

1992-01-01

190

Respiratory distress syndrome: evaluation of genetic susceptibility and protection by transmission disequilibrium test  

Microsoft Academic Search

Based on epidemiological data and genetic association studies, neonatal respiratory distress syndrome (RDS) is a complex disease with a multigenic background. The genes coding for surfactant proteins (SP) A and B have been assigned as the most likely genes in the etiology of RDS. The major factor predisposing to RDS is prematurity, and thus the phenotype of a very premature

Ritva Haataja; Riitta Marttila; Pekka Uimari; Johan Löfgren; Mika Rämet; Mikko Hallman

2001-01-01

191

RNAi phenotypes are influenced by the genetic background of the injected strain  

PubMed Central

Background RNA interference (RNAi) is a powerful tool to study gene function in organisms that are not amenable to classical forward genetics. Hence, together with the ease of comprehensively identifying genes by new generation sequencing, RNAi is expanding the scope of animal species and questions that can be addressed in terms of gene function. In the case of genetic mutants, the genetic background of the strains used is known to influence the phenotype while this has not been described for RNAi experiments. Results Here we show in the red flour beetle Tribolium castaneum that RNAi against Tc-importin ?1 leads to different phenotypes depending on the injected strain. We rule out off target effects and show that sequence divergence does not account for this difference. By quantitatively comparing phenotypes elicited by RNAi knockdown of four different genes we show that there is no general difference in RNAi sensitivity between these strains. Finally, we show that in case of Tc-importin ?1 the difference depends on the maternal genotype. Conclusions These results show that in RNAi experiments strain specific differences have to be considered and that a proper documentation of the injected strain is required. This is especially important for the increasing number of emerging model organisms that are being functionally investigated using RNAi. In addition, our work shows that RNAi is suitable to systematically identify the differences in the gene regulatory networks present in populations of the same species, which will allow novel insights into the evolution of animal diversity.

2013-01-01

192

Contribution of NTRK2 to the genetic susceptibility to anorexia nervosa, Harm avoidance and minimum body mass index  

Microsoft Academic Search

Anorexia nervosa (AN) and bulimia nervosa (BN) are eating disorders (ED) with complex genetic and environmental components. Genetic studies and animal models support the participation of brain-derived neurotrophic factor (BDNF) in the vulnerability to AN and BN. We investigated the genetic contribution of the BDNF-specific receptor neurotrophic tyrosine kinase receptor type 2 (NTRK2) to the susceptibility to ED. We have

M Ribases; M Gratacos; A Badia; L Jimenez; R Solano; J Vallejo; F Fernandez-Aranda; X Estivill

2005-01-01

193

Cardiac teratogenicity in mouse maternal phenylketonuria: defining phenotype parameters and genetic background influences.  

PubMed

Maternal phenylketonuria (MPKU) is a syndrome including cardiovascular malformations (CVMs), microcephaly, intellectual impairment, and small size for gestational age, caused by in-utero exposure to elevated serum phenylalanine (Phe) due to PKU in the mother. It is becoming a public health concern as more women with PKU reach child bearing age. Although a mouse model of PKU, BTBR Pah(enu2), has been available for 20 years, it has not been well utilized for studying MPKU. We used this model to delineate critical parameters in Phe cardiovascular teratogenicity and study the effect of genetic background. Dosing and timing experiments were performed with the BTBR Pah(enu2) mouse. A dose response curve was noted, with CVM rates at maternal serum Phe levels <360 ?M (control), 360-600 ?M (low), 600-900 ?M (mid), and >900 ?M (high) of 11.86%, 16.67%, 30.86%, and 46.67% respectively. A variety of CVMs were noted on the BTBR background, including double outlet right ventricle (DORV), aortic arch artery (AAA) abnormalities, and ventricular septal defects (VSDs). Timed exposure experiments identified a teratogenic window from embryonic day 8.5-13.5, with higher rates of conotruncal and valve defects occurring in early exposure time and persistent truncus arteriosus (PTA) and aortic arch branching abnormalities occurring with late exposure. Compared to the BTBR strain, N10+ Pah(enu2) congenics on the C3H/HeJ background had higher rates of CVMs in general and propensity to left ventricular outflow tract (LVOT) malformations, while the C57B/L6 background had similar CVM rates but predominately AAA abnormalities. We have delineated key parameters of Phe cardiovascular teratogenicity, demonstrated the utility of this MPKU model on different mouse strains, and shown how genetic background profoundly affects the phenotype. PMID:22951387

Seagraves, Nikki J; McBride, Kim L

2012-12-01

194

Fine-mapping and phenotypic analysis of the Ity3 Salmonella susceptibility locus identify a complex genetic structure.  

PubMed

Experimental animal models of Salmonella infections have been widely used to identify genes important in the host immune response to infection. Using an F2 cross between the classical inbred strain C57BL/6J and the wild derived strain MOLF/Ei, we have previously identified Ity3 (Immunity to Typhimurium locus 3) as a locus contributing to the early susceptibility of MOLF/Ei mice to infection with Salmonella Typhimurium. We have also established a congenic strain (B6.MOLF-Ity/Ity3) with the MOLF/Ei Ity3 donor segment on a C57BL/6J background. The current study was designed to fine map and characterize functionally the Ity3 locus. We generated 12 recombinant sub-congenic strains that were characterized for susceptibility to infection, bacterial load in target organs, cytokine profile and anti-microbial mechanisms. These analyses showed that the impact of the Ity3 locus on survival and bacterial burden was stronger in male mice compared to female mice. Fine mapping of Ity3 indicated that two subloci contribute collectively to the susceptibility of B6.MOLF-Ity/Ity3 congenic mice to Salmonella infection. The Ity3.1 sublocus controls NADPH oxidase activity and is characterized by decreased ROS production, reduced inflammatory cytokine response and increased bacterial burden, thereby supporting a role for Ncf2 (neutrophil cytosolic factor 2 a subunit of NADPH oxidase) as the gene underlying this sublocus. The Ity3.2 sub-locus is characterized by a hyperresponsive inflammatory cytokine phenotype after exposure to Salmonella. Overall, this research provides support to the combined action of hormonal influences and complex genetic factors within the Ity3 locus in the innate immune response to Salmonella infection in wild-derived MOLF/Ei mice. PMID:24505352

Khan, Rabia T; Yuki, Kyoko E; Malo, Danielle

2014-01-01

195

Fine-Mapping and Phenotypic Analysis of the Ity3 Salmonella Susceptibility Locus Identify a Complex Genetic Structure  

PubMed Central

Experimental animal models of Salmonella infections have been widely used to identify genes important in the host immune response to infection. Using an F2 cross between the classical inbred strain C57BL/6J and the wild derived strain MOLF/Ei, we have previously identified Ity3 (Immunity to Typhimurium locus 3) as a locus contributing to the early susceptibility of MOLF/Ei mice to infection with Salmonella Typhimurium. We have also established a congenic strain (B6.MOLF-Ity/Ity3) with the MOLF/Ei Ity3 donor segment on a C57BL/6J background. The current study was designed to fine map and characterize functionally the Ity3 locus. We generated 12 recombinant sub-congenic strains that were characterized for susceptibility to infection, bacterial load in target organs, cytokine profile and anti-microbial mechanisms. These analyses showed that the impact of the Ity3 locus on survival and bacterial burden was stronger in male mice compared to female mice. Fine mapping of Ity3 indicated that two subloci contribute collectively to the susceptibility of B6.MOLF-Ity/Ity3 congenic mice to Salmonella infection. The Ity3.1 sublocus controls NADPH oxidase activity and is characterized by decreased ROS production, reduced inflammatory cytokine response and increased bacterial burden, thereby supporting a role for Ncf2 (neutrophil cytosolic factor 2 a subunit of NADPH oxidase) as the gene underlying this sublocus. The Ity3.2 sub-locus is characterized by a hyperresponsive inflammatory cytokine phenotype after exposure to Salmonella. Overall, this research provides support to the combined action of hormonal influences and complex genetic factors within the Ity3 locus in the innate immune response to Salmonella infection in wild-derived MOLF/Ei mice.

Khan, Rabia T.; Yuki, Kyoko E.; Malo, Danielle

2014-01-01

196

The Flowering Repressor SVP Underlies a Novel Arabidopsis thaliana QTL Interacting with the Genetic Background  

PubMed Central

The timing of flowering initiation is a fundamental trait for the adaptation of annual plants to different environments. Large amounts of intraspecific quantitative variation have been described for it among natural accessions of many species, but the molecular and evolutionary mechanisms underlying this genetic variation are mainly being determined in the model plant Arabidopsis thaliana. To find novel A. thaliana flowering QTL, we developed introgression lines from the Japanese accession Fuk, which was selected based on the substantial transgression observed in an F2 population with the reference strain Ler. Analysis of an early flowering line carrying a single Fuk introgression identified Flowering Arabidopsis QTL1 (FAQ1). We fine-mapped FAQ1 in an 11 kb genomic region containing the MADS transcription factor gene SHORT VEGETATIVE PHASE (SVP). Complementation of the early flowering phenotype of FAQ1-Fuk with a SVP-Ler transgen demonstrated that FAQ1 is SVP. We further proved by directed mutagenesis and transgenesis that a single amino acid substitution in SVP causes the loss-of-function and early flowering of Fuk allele. Analysis of a worldwide collection of accessions detected FAQ1/SVP-Fuk allele only in Asia, with the highest frequency appearing in Japan, where we could also detect a potential ancestral genotype of FAQ1/SVP-Fuk. In addition, we evaluated allelic and epistatic interactions of SVP natural alleles by analysing more than one hundred transgenic lines carrying Ler or Fuk SVP alleles in five genetic backgrounds. Quantitative analyses of these lines showed that FAQ1/SVP effects vary from large to small depending on the genetic background. These results support that the flowering repressor SVP has been recently selected in A. thaliana as a target for early flowering, and evidence the relevance of genetic interactions for the intraspecific evolution of FAQ1/SVP and flowering time.

Mendez-Vigo, Belen; Martinez-Zapater, Jose M.; Alonso-Blanco, Carlos

2013-01-01

197

Multiple gene loci affecting genetic background-controlled disease resistance conferred by R gene Xa3 \\/ Xa26 in rice  

Microsoft Academic Search

The function of bacterial-blight resistance gene Xa3\\/Xa26 in rice is influenced by genetic background; the Oryza sativa L. ssp. japonica background can increase Xa3\\/Xa26 expression, resulting in an enhanced resistance. To identify whether Xa3\\/Xa26 transcript level is the only factor contributing to genetic background-controlled resistance, we screened an F2 population that was developed from a cross between Oryza sativa L.

Yan Zhou; Yinglong Cao; Yi Huang; Weibo Xie; Caiguo Xu; Xianghua Li; Shiping Wang

2009-01-01

198

Seeking genetic susceptibility variants for colorectal cancer: the EPICOLON consortium experience.  

PubMed

The EPICOLON consortium was initiated in 1999 by the Gastrointestinal Oncology Group of the Spanish Gastroenterology Association. It recruited consecutive, unselected, population-based colorectal cancer (CRC) cases and control subjects matched by age and gender without personal or familial history of cancer all over Spain with the main goal of gaining knowledge in Lynch syndrome and familial CRC. This epidemiological, prospective and multicentre study collected extensive clinical data and biological samples from ?2000 CRC cases and 2000 controls in Phases 1 and 2 involving 25 and 14 participating hospitals, respectively. Genetic susceptibility projects in EPICOLON have included candidate-gene approaches evaluating single-nucleotide polymorphisms/genes from the historical category (linked to CRC risk by previous studies), from human syntenic CRC susceptibility regions identified in mouse, from the CRC carcinogenesis-related pathways Wnt and BMP, from regions 9q22 and 3q22 with positive linkage in CRC families, and from the mucin gene family. This consortium has also participated actively in the identification 5 of the 16 common, low-penetrance CRC genetic variants identified so far by genome-wide association studies. Finishing their own pangenomic study and performing whole-exome sequencing in selected CRC samples are among EPICOLON future research prospects. PMID:22294762

Castellví-Bel, Sergi; Ruiz-Ponte, Clara; Fernández-Rozadilla, Ceres; Abulí, Anna; Muñoz, Jenifer; Bessa, Xavier; Brea-Fernández, Alejandro; Ferro, Marta; Giráldez, María Dolores; Xicola, Rosa M; Llor, Xavier; Jover, Rodrigo; Piqué, Josep M; Andreu, Montserrat; Castells, Antoni; Carracedo, Angel

2012-03-01

199

A meta-analysis of HLA-DR polymorphism and genetic susceptibility to idiopathic dilated cardiomyopathy.  

PubMed

Idiopathic dilated cardiomyopathy (IDC) has been hypothesized as a multifactorial disorder initiated by an environment trigger in individuals with predisposing human leukocyte antigen (HLA) alleles. Published data on the association between HLA-DR polymorphism and IDC risk are inconclusive. To derive a more precise estimation of the relationship, a meta-analysis was performed. A total of 19 case-control studies including 1,378 cases and 10,383 controls provided data on the association between HLA-DR polymorphism and genetic susceptibility to IDC. Overall, statistically elevated frequencies of HLA-DR4 (OR 1.58; 95% CI 1.21-2.07; P=0.0009) and HLA-DR5 (OR 1.35; 95% CI 1.05-1.73; P=0.02) alleles were found in patients with IDC compared with controls. Individuals with HLA-DR3 antigen have a protective effect against IDC (OR 0.72; 95% CI 0.58-0.90; P=0.004). In summary, this meta-analysis indicated that certain HLA-DR alleles may be genetic markers for susceptibility and resistance to IDC. PMID:21556773

Jin, Bo; Luo, Xin-Ping; Ni, Huan-Chun; Shen, Wei; Shi, Hai-Ming; Li, Yong

2012-01-01

200

Are SCN1A gene mutations responsible for genetic susceptibility to subacute sclerosing panencephalitis?  

PubMed

Dravet syndrome, characterized predominantly by myoclonus, has a striking clinical resemblance to subacute sclerosing panencephalitis (SSPE). Patients with Dravet syndrome develop significant mental decline with advancing age of affected child like in SSPE. It is well established that SCN1A gene mutations are associated with Dravet syndrome. Even periodic EEG complexes have been described in Dravet syndrome. In addition to Dravet syndrome, several other types of acute and subacute encephalopathic syndromes having clinical and electroencephalographic resemblance to SSPE are associated with SCN1A gene mutations. SSPE is a devastating progressive inflammatory disorder of the central nervous system. It is caused by persistent infection of the brain by an aberrant measles virus. Only a few of a vast number of measles infected pediatric population develop SSPE. There are several reports describing presence of SSPE is close relatives and it has been described previously in sibling and twin pairs. A genetic susceptibility for development of SSPE is likely. In fact, a variety of genetic abnormalities have already been described in patients with SSPE. It can also be argued that because of striking clinical resemblance between Dravet and various epileptic and encephalopathic syndromes associated with SCN1A gene mutations and SSPE, SCN1A gene abnormalities may also be responsible for susceptibility to SSPE in measles infected children. PMID:22098725

Garg, Ravindra Kumar

2012-02-01

201

Assessing the quality of studies supporting genetic susceptibility and outcomes of ARDS  

PubMed Central

The acute respiratory distress syndrome (ARDS) is a severe inflammatory disease manifested as a result of pulmonary and systemic responses to several insults. It is now well accepted that genetic variation influences these responses. However, little is known about the genes that are responsible for patient susceptibility and outcome of ARDS. Methodological flaws are still abundant among genetic association studies with ARDS and here, we aimed to highlight the quality criteria where the standards have not been reached, to expose the associated genes to facilitate replication attempts, and to provide quick-reference guidance for future studies. We conducted a PubMed search from January 2008 to September 2012 for original articles. Studies were considered if a statistically significant association was declared with either susceptibility or outcomes of all-cause ARDS. Fourteen criteria were used for evaluation and results were compared to those from a previous quality assessment report. Significant improvements affecting study design and statistical analysis were detected. However, major issues such as adjustments for the underlying population stratification and replication studies remain poorly addressed.

Acosta-Herrera, Marialbert; Pino-Yanes, Maria; Perez-Mendez, Lina; Villar, Jesus; Flores, Carlos

2014-01-01

202

Prevalence and susceptibility of infection to Myxobolus cerebralis, and genetic differences among populations of Tubifex tubifex.  

PubMed

The prevalence of infection and susceptibility of the aquatic oligochaete Tubifex tubifex to Myxobolus cerebralis, was examined in 2 studies on the upper Colorado River, Colorado, USA, where whirling disease occurs in wild trout populations. In the first study, the prevalence of infection ranged from 0.4 to 1.5%, as determined by counting the number of T. tubifex releasing triactinomyxons of M. cerebralis directly following their collection from the field. The susceptibility of those T. tubifex not releasing triactinomyxons was assessed by the number of these oligochaetes releasing triactinomyxons 3 mo following experimental exposures to spores of M. cerebralis. The prevalence of infection following experimental exposures of these T. tubifex ranged from 4.2 to 14.1%. In a second study, all T. tubifex collected at 2 different times directly from the 2 field sites in Colorado were exposed to spores of M. cerebralis. Individual oligochaetes representing those groups of T. tubifex releasing and those groups not releasing triactinomyxons at 3 mo were screened with molecular genetic markers. T. tubifex populations found at the 2 study sites consisted of 4 genetically distinct lineages that varied with respect to their susceptibility to experimental exposure to M. cerebralis. Lineages I and III contained the most oligochaetes susceptible to M. cerebralis and were the most prominent lineages at Windy Gap Reservoir, a site of high infectivity for wild rainbow trout on the upper Colorado River. In contrast, at the Breeze Bridge site which is below Windy Gap Reservoir and where M. cerebralis infections are less severe in wild trout, oligochaetes in lineages V and VI that are resistant to M. cerebralis were more prominent. These results suggest that certain habitats, such as Windy Gap Reservoir, are conducive to large and more homogenous populations of susceptible T. tubifex lineages that may serve as point sources of infection for M. cerebralis. Although not a direct objective of this study, there was no evidence of M. cerebralis infections among any oligochaetes other than those that would be classified as T. tubifex by standard morphological characteristics. PMID:12363083

Beauchamp, Katherine A; Gay, Melanie; Kelley, Garry O; El-Matbouli, Mansour; Kathman, R Deedee; Nehring, R Barry; Hedrick, Ronald P

2002-08-29

203

Analysis of eight genes modulating interferon gamma and human genetic susceptibility to tuberculosis: a case-control association study  

PubMed Central

Background Interferon gamma is a major macrophage-activating cytokine during infection with Mycobacterium tuberculosis, the causative pathogen of tuberculosis, and its role has been well established in animal models and in humans. This cytokine is produced by activated T helper 1 cells, which can best deal with intracellular pathogens such as M. tuberculosis. Based on the hypothesis that genes which regulate interferon gamma may influence tuberculosis susceptibility, we investigated polymorphisms in eight candidate genes. Methods Fifty-four polymorphisms in eight candidate genes were genotyped in over 800 tuberculosis cases and healthy controls in a population-based case-control association study in a South African population. Genotyping methods used included the SNPlex Genotyping System™, capillary electrophoresis of fluorescently labelled PCR products, TaqMan® SNP genotyping assays or the amplification mutation refraction system. Single polymorphisms as well as haplotypes of the variants were tested for association with TB using statistical analyses. Results A haplotype in interleukin 12B was nominally associated with tuberculosis (p = 0.02), but after permutation testing, done to assess the significance for the entire analysis, this was not globally significant. In addition a novel allele was found for the interleukin 12B D5S2941 microsatellite. Conclusions This study highlights the importance of using larger sample sizes when attempting validation of previously reported genetic associations. Initial studies may be false positives or may propose a stronger genetic effect than subsequently found to be the case.

2010-01-01

204

Genetic Control of Susceptibility to Candida albicans in SM/J Mice.  

PubMed

In the immunocompromised host, invasive infection with the fungal pathogen Candida albicans is associated with high morbidity and mortality. Sporadic cases in otherwise normal individuals are rare, and they are thought to be associated with genetic predisposition. Using a mouse model of systemic infection with C. albicans, we identified the SM/J mouse strain as unusually susceptible to infection. Genetic linkage studies in informative [C57BL/6JxSM/J]F2 mice identified a major locus on distal chromosome 15, given the appellation Carg5, that regulates C. albicans replication in SM/J mice. Cellular and molecular immunophenotyping experiments, as well as functional studies in purified cell populations from SM/J and C57BL/6J, and in [C57BL/6JxSM/J]F2 mice fixed for homozygous or heterozygous Carg5 alleles, indicate that Carg5-regulated susceptibility in SM/J is associated with a complex defect in the myeloid compartment of these mice. SM/J neutrophils express lower levels of Ly6G, and importantly, they show significantly reduced production of reactive oxygen species in response to stimulation with fMLF and PMA. Likewise, CD11b(+)Ly6G(-)Ly6C(hi) inflammatory monocytes were present at lower levels in the blood of infected SM/J, recruited less efficiently at the site of infection, and displayed blunted oxidative burst. Studies in F2 mice establish strong correlations between Carg5 alleles, Ly6G expression, production of serum CCL2 (MCP-1), and susceptibility to C. albicans. Genomic DNA sequencing of chromatin immunoprecipitated for myeloid proinflammatory transcription factors IRF1, IRF8, STAT1 and NF-?B, as well as RNA sequencing, were used to develop a "myeloid inflammatory score" and systematically analyze and prioritize potential candidate genes in the Carg5 interval. PMID:24973457

Radovanovic, Irena; Leung, Vicki; Iliescu, Alexandra; Bongfen, Silayuv E; Mullick, Alaka; Langlais, David; Gros, Philippe

2014-08-01

205

Identification of a Shared Genetic Susceptibility Locus for Coronary Heart Disease and Periodontitis  

PubMed Central

Recent studies indicate a mutual epidemiological relationship between coronary heart disease (CHD) and periodontitis. Both diseases are associated with similar risk factors and are characterized by a chronic inflammatory process. In a candidate-gene association study, we identify an association of a genetic susceptibility locus shared by both diseases. We confirm the known association of two neighboring linkage disequilibrium regions on human chromosome 9p21.3 with CHD and show the additional strong association of these loci with the risk of aggressive periodontitis. For the lead SNP of the main associated linkage disequilibrium region, rs1333048, the odds ratio of the autosomal-recessive mode of inheritance is 1.99 (95% confidence interval 1.33–2.94; P?=?6.9×10?4) for generalized aggressive periodontitis, and 1.72 (1.06–2.76; P?=?2.6×10?2) for localized aggressive periodontitis. The two associated linkage disequilibrium regions map to the sequence of the large antisense noncoding RNA ANRIL, which partly overlaps regulatory and coding sequences of CDKN2A/CDKN2B. A closely located diabetes-associated variant was independent of the CHD and periodontitis risk haplotypes. Our study demonstrates that CHD and periodontitis are genetically related by at least one susceptibility locus, which is possibly involved in ANRIL activity and independent of diabetes associated risk variants within this region. Elucidation of the interplay of ANRIL transcript variants and their involvement in increased susceptibility to the interactive diseases CHD and periodontitis promises new insight into the underlying shared pathogenic mechanisms of these complex common diseases.

Schaefer, Arne S.; Richter, Gesa M.; Groessner-Schreiber, Birte; Noack, Barbara; Nothnagel, Michael; Mokhtari, Nour-Eddine El; Loos, Bruno G.; Jepsen, S?ren; Schreiber, Stefan

2009-01-01

206

Functional Variant in Complement C3 Gene Promoter and Genetic Susceptibility to Temporal Lobe Epilepsy and Febrile Seizures  

PubMed Central

Background Human mesial temporal lobe epilepsies (MTLE) represent the most frequent form of partial epilepsies and are frequently preceded by febrile seizures (FS) in infancy and early childhood. Genetic associations of several complement genes including its central component C3 with disorders of the central nervous system, and the existence of C3 dysregulation in the epilepsies and in the MTLE particularly, make it the C3 gene a good candidate for human MTLE. Methodology/Principal Findings A case-control association study of the C3 gene was performed in a first series of 122 patients with MTLE and 196 controls. Four haplotypes (HAP1 to 4) comprising GF100472, a newly discovered dinucleotide repeat polymorphism [(CA)8 to (CA)15] in the C3 promoter region showed significant association after Bonferroni correction, in the subgroup of MTLE patients having a personal history of FS (MTLE-FS+). Replication analysis in independent patients and controls confirmed that the rare HAP4 haplotype comprising the minimal length allele of GF100472 [(CA)8], protected against MTLE-FS+. A fifth haplotype (HAP5) with medium-size (CA)11 allele of GF100472 displayed four times higher frequency in controls than in the first cohort of MTLE-FS+ and showed a protective effect against FS through a high statistical significance in an independent population of 97 pure FS. Consistently, (CA)11 allele by its own protected against pure FS in a second group of 148 FS patients. Reporter gene assays showed that GF100472 significantly influenced C3 promoter activity (the higher the number of repeats, the lower the transcriptional activity). Taken together, the consistent genetic data and the functional analysis presented here indicate that a newly-identified and functional polymorphism in the promoter of the complement C3 gene might participate in the genetic susceptibility to human MTLE with a history of FS, and to pure FS. Conclusions/Significance The present study provides important data suggesting for the first time the involvement of the complement system in the genetic susceptibility to epileptic seizures and to epilepsy.

Perroud, Nader; Ponsole-Lenfant, Magali; Cillario, Jennifer; Roll, Patrice; Roeckel-Trevisiol, Nathalie; Crespel, Ariel; Balzar, Jorg; Schlachter, Kurt; Gruber-Sedlmayr, Ursula; Pataraia, Ekaterina; Baumgartner, Christoph; Zimprich, Alexander; Zimprich, Fritz; Malafosse, Alain; Szepetowski, Pierre

2010-01-01

207

Genetic variants in IL1A and IL1B contribute to the susceptibility to 2009 pandemic H1N1 influenza A virus  

PubMed Central

Background Host genetic variations may contribute to disease susceptibility of influenza. IL-1A and IL-1B are important inflammatory cytokines that mediate the inflammation and initiate the immune response against virus infection. In this study, we investigated the relationship between single-nucleotide polymorphisms (SNPs) of Interleukin-1A (IL-1A) and Interleukin-1B (IL-1B) and the susceptibility to 2009 pandemic A/H1N1 influenza (A(H1N1)pdm09). 167 patients whom were confirmed with A(H1N1)pdm09 and 192 healthy controls were included in this study. Four SNPs (rs1304037, rs16347, rs17561, rs2071373) in IL1A gene and three SNPs (rs1143623, rs3917345, rs1143627) in IL1B gene were genotyped by using matrix-assisted laser desorption/ionization time-of-flight (MALDI-TOF) mass spectrometry platform, and the associations of the genetic variants of IL-1 with susceptibility to A(H1N1)pdm09 were then assessed. Results The polymorphisms of rs17561 in IL1A gene and rs1143627 in IL1B gene were found to be associated with susceptibility to A(H1N1)pdm09 with P values of 0.003 (OR 2.08, 95% CI 1.27-3.41) and 0.002 (OR 1.62 , 95% CI 1.20-2.18), respectively. However, no significant difference in allelic frequency was observed for other SNPs between cases and controls. Conclusions This study provides a new insight into pathogenesis of A(H1N1)pdm09, suggesting that genetic variants of IL-1A and IL-1B may exert a substantial impact on the susceptibility of A(H1N1)pdm09 virus infection.

2013-01-01

208

Combination of hearing screening and genetic screening for deafness-susceptibility genes in newborns  

PubMed Central

The aim of this study was to determine the clinical significance of the results of screening of newborn hearing and the incidence of deafness-susceptibility genes. One thousand newborn babies in the Handan Center Hospital (Handan, China) underwent screening of hearing and deafness-susceptibility genes. The first screening test was carried out using otoacoustic emissions (OAEs). Babies with hearing loss who failed to pass the initial screening were scheduled for rescreening at 42 days after birth. Cord blood was used for the screening of deafness-susceptibility genes, namely the GJB2, SLC26A4 and mitochondrial 12S rRNA (MTRNR1) genes. Among the 1,000 neonates that underwent the first hearing screening, 25 exhibited left-sided hearing loss, 21 exhibited right-sided hearing loss and 15 cases had binaural hearing loss. After rescreening 42 days later, only one of the initial 61 cases exhibited hearing loss under OAE testing. The neonatal deafness gene tests showed two cases with 1555A>G mutation and two cases with 1494C>T mutation of the MTRNR1 gene. In the SLC26A4 gene screening, four cases exhibited the heterozygous IVS7-2A>G mutation and one case exhibited heterozygous 1226G>A mutation. In the GJB2 gene screening, two cases exhibited the homozygous 427C>T mutation and 10 exhibited the heterozygous 235delC mutation. The genetic screening revealed 21 newborns with mutations in the three deafness-susceptibility genes. The overall carrier rate was 2.1% (21/1,000). The association of hearing and gene screening may be the promising screening strategy for the diagnosis of hearing loss.

YAO, GEN-DONG; LI, SHOU-XIA; CHEN, DING-LI; FENG, HAI-QIN; ZHAO, SU-BIN; LIU, YONG-JIE; GUO, LI-LI; YANG, ZHI-MING; ZHANG, XIAO-FANG; SUN, CAI-XIA; WANG, ZE-HUI; ZHANG, WEI-YONG

2014-01-01

209

The contributions of normal variation and genetic background to mammalian gene expression  

PubMed Central

Background Qualitative and quantitative variability in gene expression represents the substrate for external conditions to exert selective pressures for natural selection. Current technologies allow for some forms of genetic variation, such as DNA mutations and polymorphisms, to be determined accurately on a comprehensive scale. Other components of variability, such as stochastic events in cellular transcriptional and translational processes, are less well characterized. Although potentially important, the relative contributions of genomic versus epigenetic and stochastic factors to variation in gene expression have not been quantified in mammalian species. Results In this study we compared microarray-based measures of hepatic transcript abundance levels within and between five different strains of Mus musculus. Within each strain 23% to 44% of all genes exhibited statistically significant differences in expression between genetically identical individuals (positive false discovery rate of 10%). Genes functionally associated with cell growth, cytokine activity, amine metabolism, and ubiquitination were enriched in this group. Genetic divergence between individuals of different strains also contributed to transcript abundance level differences, but to a lesser extent than intra-strain variation, with approximately 3% of all genes exhibiting inter-strain expression differences. Conclusion These results indicate that although DNA sequence fixes boundaries for gene expression variability, there remain considerable latitudes of expression within these genome-defined limits that have the potential to influence phenotypes. The extent of normal or expected natural variability in gene expression may provide an additional level of phenotypic opportunity for natural selection.

Pritchard, Colin; Coil, David; Hawley, Sarah; Hsu, Li; Nelson, Peter S

2006-01-01

210

Genetic Background Drives Transcriptional Variation in Human Induced Pluripotent Stem Cells  

PubMed Central

Human iPS cells have been generated using a diverse range of tissues from a variety of donors using different reprogramming vectors. However, these cell lines are heterogeneous, which presents a limitation for their use in disease modeling and personalized medicine. To explore the basis of this heterogeneity we generated 25 iPS cell lines under normalised conditions from the same set of somatic tissues across a number of donors. RNA-seq data sets from each cell line were compared to identify the majority contributors to transcriptional heterogeneity. We found that genetic differences between individual donors were the major cause of transcriptional variation between lines. In contrast, residual signatures from the somatic cell of origin, so called epigenetic memory, contributed relatively little to transcriptional variation. Thus, underlying genetic background variation is responsible for most heterogeneity between human iPS cell lines. We conclude that epigenetic effects in hIPSCs are minimal, and that hIPSCs are a stable, robust and powerful platform for large-scale studies of the function of genetic differences between individuals. Our data also suggest that future studies using hIPSCs as a model system should focus most effort on collection of large numbers of donors, rather than generating large numbers of lines from the same donor.

de Brito, Miguel Cardoso; Bradley, Allan; Vallier, Ludovic; Gaffney, Daniel

2014-01-01

211

Genetic background drives transcriptional variation in human induced pluripotent stem cells.  

PubMed

Human iPS cells have been generated using a diverse range of tissues from a variety of donors using different reprogramming vectors. However, these cell lines are heterogeneous, which presents a limitation for their use in disease modeling and personalized medicine. To explore the basis of this heterogeneity we generated 25 iPS cell lines under normalised conditions from the same set of somatic tissues across a number of donors. RNA-seq data sets from each cell line were compared to identify the majority contributors to transcriptional heterogeneity. We found that genetic differences between individual donors were the major cause of transcriptional variation between lines. In contrast, residual signatures from the somatic cell of origin, so called epigenetic memory, contributed relatively little to transcriptional variation. Thus, underlying genetic background variation is responsible for most heterogeneity between human iPS cell lines. We conclude that epigenetic effects in hIPSCs are minimal, and that hIPSCs are a stable, robust and powerful platform for large-scale studies of the function of genetic differences between individuals. Our data also suggest that future studies using hIPSCs as a model system should focus most effort on collection of large numbers of donors, rather than generating large numbers of lines from the same donor. PMID:24901476

Rouhani, Foad; Kumasaka, Natsuhiko; de Brito, Miguel Cardoso; Bradley, Allan; Vallier, Ludovic; Gaffney, Daniel

2014-06-01

212

The severity of cholestatic injury is modulated by the genetic background.  

PubMed

Common bile duct ligation (CBDL) compromises the hepatic reticuloendothelial system by impairing the clearing of endotoxin and triggering an overwhelming inflammatory response. The response to endotoxin at the level of cytokine release and subsequent mortality depends on the genetic background in experimental mouse models. We hypothesized that the genetic make-up modulates the inflammatory responses after CBDL. The CBD was ligated in male A/J and B6 mice (8 weeks old). At 7 days post-CBDL, the presence of ascites was observed in 80% of B6 mice but in none of the A/J mice (P < 0.001). B6 mice showed higher mortality than A/J mice (P < 0.05). Both strains had marked cholestatic injury documented histologically. Liver chemistries were markedly elevated in both strains after injury. Plasma levels of the anti-inflammatory cytokine IL-10 were significantly higher in A/J than B6 mice at the 4- and 12-h time points (P < 0.05), whereas proinflammatory cytokine TNF-alpha levels were significantly higher in B6 than A/J mice at 2 h (P < 0.05). Both strains displayed activation of NF-kappaB after CBDL. In conclusion, the contrasting response observed after CBDL between A/J and B6 mice is largely attributable to genetic differences. Survival after CBDL was correlated with an increase in anti-inflammatory cytokines. PMID:16247325

Alaish, Samuel M; Torres, Manuel; Ferlito, Marcella; Sun, Chen-Chih; De Maio, Antonio

2005-11-01

213

Genetic Background of Patients from a University Medical Center in Manhattan: Implications for Personalized Medicine  

PubMed Central

Background The rapid progress currently being made in genomic science has created interest in potential clinical applications; however, formal translational research has been limited thus far. Studies of population genetics have demonstrated substantial variation in allele frequencies and haplotype structure at loci of medical relevance and the genetic background of patient cohorts may often be complex. Methods and Findings To describe the heterogeneity in an unselected clinical sample we used the Affymetrix 6.0 gene array chip to genotype self-identified European Americans (N?=?326), African Americans (N?=?324) and Hispanics (N?=?327) from the medical practice of Mount Sinai Medical Center in Manhattan, NY. Additional data from US minority groups and Brazil were used for external comparison. Substantial variation in ancestral origin was observed for both African Americans and Hispanics; data from the latter group overlapped with both Mexican Americans and Brazilians in the external data sets. A pooled analysis of the African Americans and Hispanics from NY demonstrated a broad continuum of ancestral origin making classification by race/ethnicity uninformative. Selected loci harboring variants associated with medical traits and drug response confirmed substantial within- and between-group heterogeneity. Conclusion As a consequence of these complementary levels of heterogeneity group labels offered no guidance at the individual level. These findings demonstrate the complexity involved in clinical translation of the results from genome-wide association studies and suggest that in the genomic era conventional racial/ethnic labels are of little value.

Tayo, Bamidele O.; Teil, Marie; Tong, Liping; Qin, Huaizhen; Khitrov, Gregory; Zhang, Weijia; Song, Quinbin; Gottesman, Omri; Zhu, Xiaofeng; Pereira, Alexandre C.; Cooper, Richard S.; Bottinger, Erwin P.

2011-01-01

214

FKBP52 deficiency-conferred uterine progesterone resistance is genetic background and pregnancy stage specific  

PubMed Central

Immunophilin FKBP52 serves as a cochaperone to govern normal progesterone (P4) receptor (PR) function. Using Fkbp52–/– mice, we show intriguing aspects of uterine P4/PR signaling during pregnancy. Implantation failure is the major phenotype found in these null females, which is conserved on both C57BL6/129 and CD1 backgrounds. However, P4 supplementation rescued implantation and subsequent decidualization in CD1, but not C57BL6/129, null females. Surprisingly, experimentally induced decidualization in the absence of blastocysts failed in Fkbp52–/– mice on either background even with P4 supplementation, suggesting that embryonic signals complement uterine signaling for this event. Another interesting finding was that while P4 at higher than normal pregnancy levels conferred PR signaling sufficient for implantation in CD1 null females, these levels were inefficient in maintaining pregnancy to full term. However, elevating P4 levels further restored PR signaling to a level optimal for successful term pregnancy with normal litter size. Collectively, the results show that the indispensability of FKBP52 in uterine P4/PR signaling is a function of genetic disparity and is pregnancy stage specific. Since there is evidence for a correlation between P4 supplementation and reduced risks of P4-resistant recurrent miscarriages and remission of endometriosis, these findings have clinical implications for genetically diverse populations of women.

Tranguch, Susanne; Wang, Haibin; Daikoku, Takiko; Xie, Huirong; Smith, David F.; Dey, Sudhansu K.

2007-01-01

215

Genetic Background Strongly Influences the Bone Phenotype of P2X7 Receptor Knockout Mice  

PubMed Central

The purinergic P2X7 receptor is expressed by bone cells and has been shown to be important in both bone formation and bone resorption. In this study we investigated the importance of the genetic background of the mouse strains on which the P2X7 knock-out models were based by comparing bone status of a new BALB/cJ P2X7?/? strain with a previous one based on the C57BL/6 strain. Female four-month-old mice from both strains were DXA scanned on a PIXImus densitometer; femurs were collected for bone strength measurements and serum for bone marker analysis. Bone-related parameters that were altered only slightly in the B6 P2X7?/? became significantly altered in the BALB/cJ P2X7?/? when compared to their wild type littermates. The BALB/cJ P2X7?/? showed reduced levels of serum C-telopeptide fragment (s-CTX), higher bone mineral density, and increased bone strength compared to the wild type littermates. In conclusion, we have shown that the genetic background of P2X7?/? mice strongly influences the bone phenotype of the P2X7?/? mice and that P2X7 has a more significant regulatory role in bone remodeling than found in previous studies.

Syberg, Susanne; Petersen, Solveig; Beck Jensen, Jens-Erik; Gartland, Alison; Teilmann, Jenni; Chessell, Iain; Steinberg, Thomas H.; Schwarz, Peter; J?rgensen, Niklas Rye

2012-01-01

216

The effect of genetic background on behavioral manifestation of Grid2(Lc) mutation.  

PubMed

Mutant mice are commonly used models of hereditary diseases. Nevertheless, these mice have phenotypic traits of the original strain, which could interfere with the manifestation of the mutation of interest. Lurcher mice represent a model of olivocerebellar degeneration, which is caused by the Grid2(Lc) mutation. Lurchers show ataxia and various cognitive and behavioral abnormalities. The most commonly used strains of Lurcher mice are B6CBA and C3H, but there is no information about the role of genetic background on the Grid2(Lc) manifestation. The aim of this work was to compare spatial navigation in the Morris water maze, spontaneous activity in the open field and motor skills on the horizontal wire, slanted ladder and rotarod in B6CBA and C3H Lurcher mutant and wild type mice. The study showed impaired motor skills and water maze performance in both strains of Lurcher mice. Both C3H Lurcher and C3H wild type mice had poorer performances in the water maze task than their B6CBA counterparts. In the open field test, C3H mice showed higher activity and lower thigmotaxis. The study showed that genetic backgrounds can modify manifestations of the Lurcher mutation. In this case, B6CBA Lurcher mice models probably have more validity when studying the behavioral aspects of cerebellar degeneration than C3H Lurcher mice, since they do not combine abnormalities related to the Grid2(Lc) mutation with strain-specific problems. PMID:24937052

Cendelin, Jan; Tuma, Jan; Korelusova, Ivana; Vozeh, Frantisek

2014-09-01

217

Anatomical Differences and Atherosclerosis in Apolipoprotein E - Deficient Mice with 129/SvEv and C57BL/6 Genetic Backgrounds  

PubMed Central

There are well-known genetic background effects on atherosclerosis susceptibility in mice. To study the basis of these effects, we have generated the apolipoprotein E-null mutation in mouse embryonic stem cells of 129/SvEv origin, maintained it in the inbred strain (129-apoE), and compared these mice with those previously made in strain 129/Ola and backcrossed to a C57BL/6 genetic background (B6-apoE). Plasma cholesterol and triglyceride levels in the apoE-129 mice are twice the levels in apoE-B6, and both VLDL/chylomicron remnants and HDL particles are increased. Regression analysis of plaque size relative to the age of mice suggests that the initiation of atherosclerotic plaque development at the aortic root is slower in 129-apoE mice (intercept at 3.9 mo in females and 4.1 mo in males) than in B6-apoE mice (1.3 mo in females and 2.8 mo in males). In contrast, 129-apoE mice develop extensive plaques in the aortic arches earlier than B6-apoE mice. Distinct differences in the geometry of the aortic arch between the two strains suggest that anatomical differences may contribute to the effects of genetic background on atherosclerosis. The 129-apoE/B6-apoE pair thus provides a tool to study factors governing the relation between arterial geometry and the location of plaque development.

Maeda, Nobuyo; Johnson, Lance; Kim, Shinja; Hagaman, John; Friedman, Morton; Reddick, Robert

2007-01-01

218

Allele-specific Hras Mutations and Genetic Alterations at Tumor Susceptibility Loci in Skin Carcinomas from Interspecific Hybrid Mice1  

Microsoft Academic Search

We have investigated the effects of germ-line variants that influence skin tumor susceptibility loci on the patterns of somatic genetic alterations in mouse skin cancers. Using a two-stage skin carcinogenesis model, we previ- ously identified at least 13 skin tumor susceptibility ( Skts) loci in a large interspecific F1 backcross ((NIH\\/Ola M. spretus) NIH\\/Ola) study. In this report, we describe

Hiroki Nagase; Jian-Hua Mao; Allan Balmain

2003-01-01

219

Integrated Genetic and Epigenetic Analysis Identifies Haplotype-Specific Methylation in the FTO Type 2 Diabetes and Obesity Susceptibility Locus  

Microsoft Academic Search

Recent multi-dimensional approaches to the study of complex disease have revealed powerful insights into how genetic and epigenetic factors may underlie their aetiopathogenesis. We examined genotype-epigenotype interactions in the context of Type 2 Diabetes (T2D), focussing on known regions of genomic susceptibility. We assayed DNA methylation in 60 females, stratified according to disease susceptibility haplotype using previously identified association loci.

Christopher G. Bell; Sarah Finer; Cecilia M. Lindgren; Gareth A. Wilson; Vardhman K. Rakyan; Andrew E. Teschendorff; Pelin Akan; Elia Stupka; Thomas A. Down; Inga Prokopenko; Ian M. Morison; Jonathan Mill; Ruth Pidsley; Panos Deloukas; Timothy M. Frayling; Andrew T. Hattersley; Mark I. McCarthy; Stephan Beck; Graham A. Hitman; Thorkild I. A. Sorensen

2010-01-01

220

Genetic variation between Biomphalaria alexandrina snails susceptible and resistant to Schistosoma mansoni infection.  

PubMed

Much effort has been made to control schistosomiasis infection in Egypt. However, enduring effects from such strategies have not yet been achieved. In this study, we sought to determine the genetic variability related to the interaction between Biomphalaria alexandrina snails and Schistosoma mansoni. Using RAPD-PCR with eight (10 mers) random primers, we were able to determine the polymorphic markers that differed between snails susceptible and resistant to Schistosoma mansoni infection using five primers out of the eight. Our results suggest that the RAPD-PCR technique is an efficient means by which to compare genomes and to detect genetic variations between schistosomiasis intermediate hosts. The RAPD technique with the above-noted primers can identify genomic markers that are specifically related to the Biomphalaria alexandrina/Schistosoma mansoni relationship in the absence of specific nucleotide sequence information. This approach could be used in epidemiologic surveys to investigate genetic diversity among Biomphalaria alexandrina snails. The ability to determine resistant markers in Biomphalaria alexandrina snails could potentially lead to further studies that use refractory snails as agents to control the spread of schistosomiasis. PMID:23878796

El-Nassery, Suzanne M F; Abou-El-Naga, Iman F; Allam, Sonia R; Shaat, Eman A; Mady, Rasha F M

2013-01-01

221

Implication of IL-2/IL-21 region in systemic sclerosis genetic susceptibility  

PubMed Central

Objective The interleukin 2 (IL-2) and interleukin 21 (IL-21) locus at chromosome 4q27 has been associated with several autoimmune diseases, and both genes are related to immune system functions. The aim of this study was to evaluate the role of the IL-2/IL-21 locus in systemic sclerosis (SSc). Patients and methods The case control study included 4493 SSc Caucasian patients and 5856 healthy controls from eight Caucasian populations (Spain, Germany, The Netherlands, USA, Italy, Sweden, UK and Norway). Four single nucleotide polymorphisms (rs2069762, rs6822844, rs6835457 and rs907715) were genotyped using TaqMan allelic discrimination assays. Results We observed evidence of association of the rs6822844 and rs907715 variants with global SSc (pc=6.6E-4 and pc=7.2E-3, respectively). Similar statistically significant associations were observed for the limited cutaneous form of the disease. The conditional regression analysis suggested that the most likely genetic variation responsible for the association was the rs6822844 polymorphism. Consistently, the rs2069762A-rs6822844T-rs6835457G-rs907715T allelic combination showed evidence of association with SSc and limited cutaneous SSc subtype (pc=1.7E-03 and pc=8E-4, respectively). Conclusions These results suggested that the IL-2/IL-21 locus influences the genetic susceptibility to SSc. Moreover, this study provided further support for the IL-2/IL-21 locus as a common genetic factor in autoimmune diseases.

Diaz-Gallo, Lina-Marcela; Simeon, Carmen P; Broen, Jasper C; Ortego-Centeno, Norberto; Beretta, Lorenzo; Vonk, Madelon C; Carreira, Patricia E; Vargas, Sofia; Roman-Ivorra, Jose Andres; Gonzalez-Gay, Miguel A; Tolosa, Carlos; Lopez-Longo, Francisco Javier; Espinosa, Gerard; Vicente, Esther F; Hesselstrand, Roger; Riemekasten, Gabriela; Witte, Torsten; Distler, Jorg H W; Voskuyl, Alexandre E; Schuerwegh, Annemie J; Shiels, Paul G; Nordin, Annika; Padyukov, Leonid; Hoffmann-Vold, Anna-Maria; Scorza, Raffaella; Lunardi, Claudio; Airo, Paolo; van Laar, Jacob M; Hunzelmann, Nicolas; Gathof, Birgit S; Kreuter, Alexander; Herrick, Ariane; Worthington, Jane; Denton, Christopher P; Zhou, Xiaodong; Arnett, Frank C; Fonseca, Carmen; Koeleman, Bobby PC; Assasi, Shervin; Radstake, Timothy R D J; Mayes, Maureen D; Martin, Javier

2013-01-01

222

Genome-wide meta-analysis of genetic susceptible genes for Type 2 Diabetes  

PubMed Central

Background Many genetic studies, including single gene studies and Genome-wide association studies (GWAS), aim to identify risk alleles for genetic diseases such as Type II Diabetes (T2D). However, in T2D studies, there is a significant amount of the hereditary risk that cannot be simply explained by individual risk genes. There is a need for developing systems biology approaches to integrate comprehensive genetic information and provide new insight on T2D biology. Methods We performed comprehensive integrative analysis of Single Nucleotide Polymorphisms (SNP's) individually curated from T2D GWAS results and mapped them to T2D candidate risk genes. Using protein-protein interaction data, we constructed a T2D-specific molecular interaction network consisting of T2D genetic risk genes and their interacting gene partners. We then studied the relationship between these T2D genes and curated gene sets. Results We determined that T2D candidate risk genes are concentrated in certain parts of the genome, specifically in chromosome 20. Using the T2D genetic network, we identified highly-interconnected network "hub" genes. By incorporating T2D GWAS results, T2D pathways, and T2D genes' functional category information, we further ranked T2D risk genes, T2D-related pathways, and T2D-related functional categories. We found that highly-interconnected T2D disease network “hub” genes most highly associated to T2D genetic risks to be PI3KR1, ESR1, and ENPP1. The well-characterized TCF7L2, contractor to our expectation, was not among the highest-ranked T2D gene list. Many interacted pathways play a role in T2D genetic risks, which includes insulin signalling pathway, type II diabetes pathway, maturity onset diabetes of the young, adipocytokine signalling pathway, and pathways in cancer. We also observed significant crosstalk among T2D gene subnetworks which include insulin secretion, regulation of insulin secretion, response to peptide hormone stimulus, response to insulin stimulus, peptide secretion, glucose homeostasis, and hormone transport. Overview maps involving T2D genes, gene sets, pathways, and their interactions are all reported. Conclusions Large-scale systems biology meta-analyses of GWAS results can improve interpretations of genetic variations and genetic risk factors. T2D genetic risks can be attributable to the summative genetic effects of many genes involved in a broad range of signalling pathways and functional networks. The framework developed for T2D studies may serve as a guide for studying other complex diseases.

2012-01-01

223

Autism genetic database (AGD): a comprehensive database including autism susceptibility gene-CNVs integrated with known noncoding RNAs and fragile sites  

PubMed Central

Background Autism is a highly heritable complex neurodevelopmental disorder, therefore identifying its genetic basis has been challenging. To date, numerous susceptibility genes and chromosomal abnormalities have been reported in association with autism, but most discoveries either fail to be replicated or account for a small effect. Thus, in most cases the underlying causative genetic mechanisms are not fully understood. In the present work, the Autism Genetic Database (AGD) was developed as a literature-driven, web-based, and easy to access database designed with the aim of creating a comprehensive repository for all the currently reported genes and genomic copy number variations (CNVs) associated with autism in order to further facilitate the assessment of these autism susceptibility genetic factors. Description AGD is a relational database that organizes data resulting from exhaustive literature searches for reported susceptibility genes and CNVs associated with autism. Furthermore, genomic information about human fragile sites and noncoding RNAs was also downloaded and parsed from miRBase, snoRNA-LBME-db, piRNABank, and the MIT/ICBP siRNA database. A web client genome browser enables viewing of the features while a web client query tool provides access to more specific information for the features. When applicable, links to external databases including GenBank, PubMed, miRBase, snoRNA-LBME-db, piRNABank, and the MIT siRNA database are provided. Conclusion AGD comprises a comprehensive list of susceptibility genes and copy number variations reported to-date in association with autism, as well as all known human noncoding RNA genes and fragile sites. Such a unique and inclusive autism genetic database will facilitate the evaluation of autism susceptibility factors in relation to known human noncoding RNAs and fragile sites, impacting on human diseases. As a result, this new autism database offers a valuable tool for the research community to evaluate genetic findings for this complex multifactorial disorder in an integrated format. AGD provides a genome browser and a web based query client for conveniently selecting features of interest. Access to AGD is freely available at .

Matuszek, Gregory; Talebizadeh, Zohreh

2009-01-01

224

Impact of Genetic Background on Neonatal Lethality of Gga2 Gene-Trap Mice  

PubMed Central

The functional redundancy of the three mammalian Golgi-localized, ?-ear–containing, ADP-ribosylation factor-binding proteins (GGAs) was addressed in a previous study. Using insertional mutagenesis, we found that Gga1 or Gga3 homozygous knockout mice were for the most part normal, whereas mice homozygous for two different Gga2 gene-trap alleles exhibited either embryonic or neonatal lethality in the C57BL/6 background, depending on the source of the vector utilized (Byg vs. Tigm, respectively). We now show that the Byg strain harbors a disrupted Gga2 allele that is hypomorphic, indicating that the Byg lethality is attributable to a mechanism independent of GGA2. This is in contrast to the Tigm Gga2 allele, which is a true knockout and establishes a role for GGA2 during the neonatal period. Placement of the Tigm Gga2 allele into the C57BL6/Ola129Sv mixed background results in a lower incidence of neonatal lethality, showing the importance of genetic background in determining the requirement for GGA2 during this period. The Gga2?/? mice that survive have reduced body weight at birth and this runted phenotype is maintained through adulthood.

Doray, Balraj; Govero, Jennifer; Kornfeld, Stuart

2014-01-01

225

Sequence variant classification and reporting: recommendations for improving the interpretation of cancer susceptibility genetic test results  

PubMed Central

Genetic testing of cancer susceptibility genes is now widely applied in clinical practice to predict risk of developing cancer. In general, sequence-based testing of germline DNA is used to determine whether an individual carries a change that is clearly likely to disrupt normal gene function. Genetic testing may detect changes that are clearly pathogenic, clearly neutral or variants of unclear clinical significance. Such variants present a considerable challenge to the diagnostic laboratory and the receiving clinician in terms of interpretation and clear presentation of the implications of the result to the patient. There does not appear to be a consistent approach to interpreting and reporting the clinical significance of variants either among genes or among laboratories. The potential for confusion among clinicians and patients is considerable and misinterpretation may lead to inappropriate clinical consequences. In this article we review the current state of sequence-based genetic testing, describe other standardized reporting systems used in oncology and propose a standardized classification system for application to sequence based results for cancer predisposition genes. We suggest a system of five classes of variants based on the degree of likelihood of pathogenicity. Each class is associated with specific recommendations for clinical management of at-risk relatives that will depend on the syndrome. We propose that panels of experts on each cancer predisposition syndrome facilitate the classification scheme and designate appropriate surveillance and cancer management guidelines. The international adoption of a standardized reporting system should improve the clinical utility of sequence-based genetic tests to predict cancer risk.

Plon, Sharon E.; Eccles, Diana M.; Easton, Douglas; Foulkes, William D.; Genuardi, Maurizio; Greenblatt, Marc S.; Hogervorst, Frans B.L.; Hoogerbrugge, Nicoline; Spurdle, Amanda B.; Tavtigian, Sean

2011-01-01

226

Carbimazole-induced myositis in the treatment of Graves' disease: a complication in genetically susceptible individuals?  

PubMed

A 24-year-old Chinese woman with Graves' disease presented with myositis two months after treatment with carbimazole. The patient's myositis resolved with hydration and cessation of carbimazole. No other causes of myositis were found, and a change in the medication to propylthiouracil was uneventful. Review of the literature suggests a possible genetic susceptibility, as the majority of reported cases are Asian in origin, similar to patients who present with thyroid periodic paralysis. Changing the antithyroid drugs (ATDs) administered, decreasing the dose of pre-existing ATDs in the treatment regimen or addition of levothyroxine has been shown to result in clinical improvement of this complication. These observations suggest various mechanisms of carbimazole-induced myositis in the treatment of Graves' disease, including the direct effect of ATDs on myocytes, immune-related responses secondary to ATDs and rapid decrements in thyroid hormone with ensuing myositis. PMID:23900475

Lim, Adoree Yi Ying; Kek, Peng Chin; Soh, Abel Wah Ek

2013-07-01

227

Arsenic-induced genotoxicity and genetic susceptibility to arsenic-related pathologies.  

PubMed

The arsenic (As) exposure represents an important problem in many parts of the World. Indeed, it is estimated that over 100 million individuals are exposed to arsenic, mainly through a contamination of groundwaters. Chronic exposure to As is associated with adverse effects on human health such as cancers, cardiovascular diseases, neurological diseases and the rate of morbidity and mortality in populations exposed is alarming. The purpose of this review is to summarize the genotoxic effects of As in the cells as well as to discuss the importance of signaling and repair of arsenic-induced DNA damage. The current knowledge of specific polymorphisms in candidate genes that confer susceptibility to arsenic exposure is also reviewed. We also discuss the perspectives offered by the determination of biological markers of early effect on health, incorporating genetic polymorphisms, with biomarkers for exposure to better evaluate exposure-response clinical relationships as well as to develop novel preventative strategies for arsenic-health effects. PMID:23583964

Faita, Francesca; Cori, Liliana; Bianchi, Fabrizio; Andreassi, Maria Grazia

2013-04-01

228

Arsenic-Induced Genotoxicity and Genetic Susceptibility to Arsenic-Related Pathologies  

PubMed Central

The arsenic (As) exposure represents an important problem in many parts of the World. Indeed, it is estimated that over 100 million individuals are exposed to arsenic, mainly through a contamination of groundwaters. Chronic exposure to As is associated with adverse effects on human health such as cancers, cardiovascular diseases, neurological diseases and the rate of morbidity and mortality in populations exposed is alarming. The purpose of this review is to summarize the genotoxic effects of As in the cells as well as to discuss the importance of signaling and repair of arsenic-induced DNA damage. The current knowledge of specific polymorphisms in candidate genes that confer susceptibility to arsenic exposure is also reviewed. We also discuss the perspectives offered by the determination of biological markers of early effect on health, incorporating genetic polymorphisms, with biomarkers for exposure to better evaluate exposure-response clinical relationships as well as to develop novel preventative strategies for arsenic- health effects.

Faita, Francesca; Cori, Liliana; Bianchi, Fabrizio; Andreassi, Maria Grazia

2013-01-01

229

Association between the APC gene D1822V variant and the genetic susceptibility of colorectal cancer  

PubMed Central

Adenomatous polyposis coli (APC) gene polymorphisms are believed to contribute to tumor susceptibility. However, the association between genetic variants (A/T) in the APC gene D1822V polymorphism and colorectal cancer (CRC) susceptibility remains unknown. To determine this association, a case-control study was performed. The genotype of the APC gene D1822V variants was analyzed by DNA sequencing in blood samples collected from 196 patients with CRC and 279 healthy subjects. There were no significant associations between the case and control groups in the distribution of AT [odds ratio (OR), 0.604; 95% confidence interval (CI), 0.355–1.029) and TT genotypes (OR, 0.438; 95% CI, 0.045–4.247) relative to the AA genotype. The ratio of the T allele was significantly lower (P=0.047) in the case group compared with the control group (OR, 0.611; 95% CI, 0.374–0.997), indicating that the T allele conferred a protective effect in CRC. The frequency of the AT genotype among the subjects diagnosed at >45 years of age was lower than those diagnosed at a younger age (P<0.05). The present study demonstrates that the T allele of the D1822V polymorphism may exert a protective effect against CRC, however, these findings require further validation in a larger sample size.

FENG, MAOHUI; FANG, XIPING; YANG, QIAN; OUYANG, GANG; CHEN, DAPING; MA, XIANG; LI, HUACHI; XIE, WEI

2014-01-01

230

Fowl Immunoglobulins: Quantitation in Birds Genetically Resistant and Susceptible to Marek's Disease.  

PubMed

The development of serum immunoglobulins was observed in chicks genetically resistant (N line) and susceptible (P line) to Marek's disease (MD), in conditions free from infection with MD. IgG was present at hatching at about 5.0 mg/ml and decreased to about 0.5 mg/ml by 12 to 15 days. Active production of IgG was apparent at about 20 days of age and reached levels of 2.0 to 3.0 mg/ml by 67 days. Low levels of IgM were present at hatching, and a gradual increase was seen to 1.0 to 2.0 mg/ml by 67 days. IgA was not detectable at hatching; it appeared in N-line birds at 5 days and in P-line birds at 13 days, and by 67 days was about 0.10 to 0.13 mg/ml. After 30 to 40 days, immunoglobulin levels were generally higher in N-line than in P-line birds. However, it was concluded that no primary immunoglobin deficiency existed sufficient to explain the susceptibility of the P-line birds to MD. PMID:16558118

Higgins, D A; Calnek, B W

1975-08-01

231

Autoimmune thyroid diseases: genetic susceptibility of thyroid-specific genes and thyroid autoantigens contributions.  

PubMed

Autoimmune thyroid diseases are common polygenic multifactorial disorders with the environment contributing importantly to the emergence of the disease phenotype. Some of the disease manifestations, such as severe thyroid-associated ophthalmopathy, pretibial myxedema and thyroid antigen/antibody immune complex nephritis are unusual to rare. The spectrum of autoimmune thyroid diseases includes: Graves' disease (GD), Hashimoto's thyroiditis (HT), atrophic autoimmune thyroiditis, postpartum thyroiditis, painless thyroiditis unrelated to pregnancy and thyroid-associated ophthalmopathy. This spectrum present contrasts in terms of thyroid function, disease duration and spread to other anatomic location. The genetic basis of autoimmune thyroid disease (AITD) is complex and likely to be due to genes of both large and small effects. In GD the autoimmune process results in the production of thyroid-stimulating antibodies and lead to hyperthyroidism, whereas in HT the end result is destruction of thyroid cells and hypothyroidism. Recent studies in the field of autoimmune thyroid diseases have largely focused on (i) the genes involved in immune response and/or thyroid physiology with could influence susceptibility to disease, (ii) the delineation of B-cell autoepitopes recognized by the main autoantigens, thyroglobulin, thyroperoxidase and TSH receptor, to improve our understanding of how these molecules are seen by the immune system and (iii) the regulatory network controlling the synthesis of thyroid hormones and its dysfunction in AITD. The aim of the present review is to summarize the current knowledge regarding the relation existing between some susceptibility genes, autoantigens and dysfunction of thyroid function during AITD. PMID:19284442

Hadj-Kacem, H; Rebuffat, S; Mnif-Féki, M; Belguith-Maalej, S; Ayadi, H; Péraldi-Roux, S

2009-04-01

232

Genetic variation in the hypothalamic–pituitary–adrenal stress axis influences susceptibility to musculoskeletal pain: results from the EPIFUND study  

Microsoft Academic Search

ObjectivesTo determine if genetic variation in genes in the hypothalamic–pituitary–adrenal (HPA) axis, the primary stress response system, influences susceptibility to developing musculoskeletal pain.MethodsPain and comorbidity data was collected at three time points in a prospective population-based cohort study. Pairwise tagging single nucleotide polymorphisms (SNPs) were selected and genotyped for seven genes. Genetic association analysis was carried out using zero-inflated negative

Kate L Holliday; Barbara I Nicholl; Gary J Macfarlane; Wendy Thomson; Kelly A Davies; John McBeth

2010-01-01

233

Genetic background impacts soluble and cell wall-bound aromatics in brown midrib mutants of sorghum.  

PubMed

Sorghum (Sorghum bicolor (L.). Moench) BMR-6 and BMR-12 encode cinnamylalcohol dehydrogenase and caffeic acid-O-methyltransferase, respectively. We have evaluated the impact of two bmr alleles, bmr-6 and bmr-12, respectively, on soluble and wall-bound aromatics in near isogenic, wild-type (WT), bmr-6, bmr-12 and double-mutant (DM; bmr-6 and bmr-12) plants in two genetic backgrounds, RTx430 and Wheatland. Immunoblots confirmed that COMT protein was essentially absent in bmr-12 and DM plants, but was present in bmr-6 and WT plants. In contrast, although CAD activity was not detected in bmr-6 and DM plants, proteins crossreacting to anti-CAD sera were found in stem extracts from all genotypes. In both sorghum backgrounds, WT plants had lowest amounts of free aromatics, higher levels of cell wall-bound pCA and FA esters and guaiacyl (G), syringyl (S), and p-hydroxyphenyl (H) lignins. Soluble aromatics and cell wall phenolic ester content in Wheatland DM plants resembled that of Wheatland bmr-6 plants, whereas in the RTx430 background, levels of these components in the DM plants more closely resembled those observed in bmr-12 plants. In both backgrounds, bmr-6 plants exhibited reduced levels of G, S, and H lignins relative to WT, and increased incorporation of G-indene into lignin. In bmr-12 plants, there was greater incorporation of G- and 5-hydroxyguaiacyl (5-OHG) lignin into cell walls. Histochemical staining of internode sections from Wheatland plants indicated that apparent lignification of cortical sclerenchyma and vascular bundle fibers was greatest and most uniform in WT plants. Relative staining intensity of these tissues was decreased in bmr-6, followed by bmr-12 plants. DM plants exhibited poor staining of cortical sclerenchyma and vascular bundle fibers. PMID:18795321

Palmer, Nathan A; Sattler, Scott E; Saathoff, Aaron J; Funnell, Deanna; Pedersen, Jeffery F; Sarath, Gautam

2008-12-01

234

SAP modulates B cell functions in a genetic background-dependent manner.  

PubMed

Mutations affecting the SLAM-associated protein (SAP) are responsible for the X-linked lympho-proliferative syndrome (XLP), a severe primary immunodeficiency syndrome with disease manifestations that include fatal mononucleosis, B cell lymphoma and dysgammaglobulinemia. It is well accepted that insufficient help by SAP-/- CD4+ T cells, in particular during the germinal center reaction, is a component of dysgammaglobulinemia in XLP patients and SAP-/- animals. It is however not well understood whether in XLP patients and SAP-/- mice B cell functions are affected, even though B cells themselves do not express SAP. Here we report that B cell intrinsic responses to haptenated protein antigens are impaired in SAP-/- mice and in Rag-/- mice into which B cells derived from SAP-/- mice together with wt CD4+ T cells had been transferred. This impaired B cells functions are in part depending on the genetic background of the SAP-/- mouse, which affects B cell homeostasis. Surprisingly, stimulation with an agonistic anti-CD40 causes strong in vivo and in vitro B cell responses in SAP-/- mice. Taken together, the data demonstrate that genetic factors play an important role in the SAP-related B cell functions. The finding that anti-CD40 can in part restore impaired B cell responses in SAP-/- mice, suggests potentially novel therapeutic interventions in subsets of XLP patients. PMID:23806511

Detre, Cynthia; Yigit, Burcu; Keszei, Marton; Castro, Wilson; Magelky, Erica M; Terhorst, Cox

2013-06-01

235

SAP modulates B cell functions in a genetic background-dependent manner  

PubMed Central

Mutations affecting the SLAM-associated protein (SAP) are responsible for the X-linked lympho-proliferative syndrome (XLP), a severe primary immunodeficiency syndrome with disease manifestations that include fatal mononucleosis, B cell lymphoma and dysgammaglobulinemia. It is well accepted that insufficient help by SAP?/? CD4+ T cells, in particular during the germinal center reaction, is a component of dysgammaglobulinemia in XLP patients and SAP?/? animals. It is however not well understood whether in XLP patients and SAP?/? mice B cell functions are affected, even though B cells themselves do not express SAP. Here we report that B cell intrinsic responses to haptenated protein antigens are impaired in SAP?/? mice and in Rag?/? mice into which B cells derived from SAP?/? mice together with wt CD4+ T cells had been transferred. This impaired B cells functions are in part depending on the genetic background of the SAP?/? mouse, which affects B cell homeostasis. Surprisingly, stimulation with an agonistic anti-CD40 causes strong in vivo and in vitro B cell responses in SAP?/? mice. Taken together, the data demonstrate that genetic factors play an important role in the SAP-related B cell functions. The finding that anti-CD40 can in part restore impaired B cell responses in SAP?/? mice, suggests potentially novel therapeutic interventions in subsets of XLP patients.

Detre, Cynthia; Yigit, Burcu; Keszei, Marton; Castro, Wilson; Magelky, Erica M.; Terhorst, Cox

2013-01-01

236

Early neonatal inflammation affects adult pain reactivity and anxiety related traits in mice: genetic background counts.  

PubMed

Protracted or recurrent pain and inflammation in the early neonatal period may cause long-lasting changes in central neural function. However, more research is necessary to better characterize the long-term behavioral sequelae of such exposure in the neonatal period. Objectives: (1) to study whether timing of postnatal exposure to persistent inflammation alters responsiveness to thermal pain in the adult animal; (2) to assess whether animals experiencing early postnatal chronic inflammation display altered anxiety related behavior; (3) to study the importance of genetic background. Newborn mice (outbred strain, CD1 and F1 hybrid strain, B6C3F1) received an injection of Complete Freund's Adjuvant (CFA) or saline on either postnatal day 1 or 14 (PND1; PND14) into the left hind paw. Pain to radiant heat and anxiety were examined in 12-week-old adult animals. Adult baseline PWL was significantly decreased in CD1 mice exposed to CFA on PND 1 and 14 as compared to their saline treated counterparts. B6C3F1 mice exposed to CFA on PND14 showed markedly reduced baseline PWL compared to the PND14 saline group. Persistent inflammation experienced by B6C3F1 mice on PND1 failed to affect baseline adult thermal responsiveness. Adult mice, CD1 and B6C3F1, displayed low anxiety traits only if they had been exposed to persistent inflammation on PND1 and not on PND14. Our research suggests a role for genetic background in modulating long-term behavioral consequences of neonatal persistent inflammation: the data support the hypothesis that pain experienced very early in life differentially affects adult behavioral and emotional responsiveness in outbred (CD1) and hybrid mice (B6C3F1). PMID:19665540

Benatti, Cristina; Alboni, Silvia; Capone, Giacomo; Corsini, Daniela; Caggia, Federica; Brunello, Nicoletta; Tascedda, Fabio; Blom, Joan M C

2009-11-01

237

Ozone exposure, vitamin C intake, and genetic susceptibility of asthmatic children in Mexico City: a cohort study  

PubMed Central

Background We previously reported that asthmatic children with GSTM1 null genotype may be more susceptible to the acute effect of ozone on the small airways and might benefit from antioxidant supplementation. This study aims to assess the acute effect of ozone on lung function (FEF25-75) in asthmatic children according to dietary intake of vitamin C and the number of putative risk alleles in three antioxidant genes: GSTM1, GSTP1 (rs1695), and NQO1 (rs1800566). Methods 257 asthmatic children from two cohort studies conducted in Mexico City were included. Stratified linear mixed models with random intercepts and random slopes on ozone were used. Potential confounding by ethnicity was assessed. Analyses were conducted under single gene and genotype score approaches. Results The change in FEF25-75 per interquartile range (60?ppb) of ozone in persistent asthmatic children with low vitamin C intake and GSTM1 null was ?91.2?ml/s (p?=?0.06). Persistent asthmatic children with 4 to 6 risk alleles and low vitamin C intake showed an average decrement in FEF25-75 of 97.2?ml/s per 60?ppb of ozone (p?=?0.03). In contrast in children with 1 to 3 risk alleles, acute effects of ozone on FEF25-75 did not differ by vitamin C intake. Conclusions Our results provide further evidence that asthmatic children predicted to have compromised antioxidant defense by virtue of genetic susceptibility combined with deficient antioxidant intake may be at increased risk of adverse effects of ozone on pulmonary function.

2013-01-01

238

Integrating mechanistic and polymorphism data to characterize human genetic susceptibility for environmental chemical risk assessment in the 21st century.  

PubMed

Response to environmental chemicals can vary widely among individuals and between population groups. In human health risk assessment, data on susceptibility can be utilized by deriving risk levels based on a study of a susceptible population and/or an uncertainty factor may be applied to account for the lack of information about susceptibility. Defining genetic susceptibility in response to environmental chemicals across human populations is an area of interest in the NAS' new paradigm of toxicity pathway-based risk assessment. Data from high-throughput/high content (HT/HC), including -omics (e.g., genomics, transcriptomics, proteomics, metabolomics) technologies, have been integral to the identification and characterization of drug target and disease loci, and have been successfully utilized to inform the mechanism of action for numerous environmental chemicals. Large-scale population genotyping studies may help to characterize levels of variability across human populations at identified target loci implicated in response to environmental chemicals. By combining mechanistic data for a given environmental chemical with next generation sequencing data that provides human population variation information, one can begin to characterize differential susceptibility due to genetic variability to environmental chemicals within and across genetically heterogeneous human populations. The integration of such data sources will be informative to human health risk assessment. PMID:21291902

Mortensen, Holly M; Euling, Susan Y

2013-09-15

239

Genetics and Biomarkers of Moyamoya Disease: Significance of RNF213 as a Susceptibility Gene  

PubMed Central

Moyamoya disease is characterized by a progressive stenosis at the terminal portion of the internal carotid artery and an abnormal vascular network at the base of the brain. Although its etiology is still unknown, recent genome-wide and locus-specific association studies identified RNF213 as an important susceptibility gene of moyamoya disease among East Asian population. A polymorphism in c.14576G>A in RNF213 was identified in 95% of familial patients with moyamoya disease and 79% of sporadic cases, and patients having this polymorphism were found to have significantly earlier disease onset and a more severe form of moyamoya disease, such as the presentation of cerebral infarction and posterior cerebral artery stenosis. The exact mechanism by which the RNF213 abnormality relates to moyamoya disease remains unknown, while recent reports using genetically engineered mice lacking RNF213 by homologous recombination provide new insight for the pathogenesis of this rare entity. Regarding biomarkers of moyamoya disease, moyamoya disease is characterized by an increased expression of angiogenic factors and pro-inflammatory molecules such as vascular endothelial growth factors and matrix metalloproteinase-9, which may partly explain its clinical manifestations of the pathologic angiogenesis, spontaneous hemorrhage, and higher incidence of cerebral hyperperfusion after revascularization surgery. More recently, blockade of these pro-inflammatory molecules during perioperative period is attempted to reduce the potential risk of surgical complication including cerebral hyperperfusion syndrome. In this review article, we focus on the genetics and biomarkers of moyamoya disease, and sought to discuss their clinical implication.

Sonobe, Shinya; Nishijima, Yasuo; Niizuma, Kuniyasu; Sakata, Hiroyuki; Kure, Shigeo; Tominaga, Teiji

2014-01-01

240

Genetic variation in complement regulators and susceptibility to age-related macular degeneration  

PubMed Central

Objectives Age-related macular degeneration (AMD) is the commonest cause of blindness in Western populations. Risk is influenced by age, genetic and environmental factors. Complement activation appears to be important in the pathogenesis and associations have been found between AMD and genetic variations in complement regulators such as complement factor H. We therefore investigated other complement regulators for association with AMD. Methods We carried out a case–control study to test for association between AMD and single nucleotide polymorphisms (SNPs) spanning the genes encoding complement factor P (CFP, properdin), CD46 (membrane cofactor protein, MCP), CD55 (decay accelerating factor, DAF) and CD59 (protectin). All cases and controls were examined by an ophthalmologist and had independent grading of fundus photographs to confirm their disease status. Results 20 SNPs were genotyped in 446 cases and 262 controls. For two SNPs with p-values approaching significance additional subjects were genotyped to increase the numbers to 622 cases and 359 controls. There was no evidence of association between AMD and any of the SNPs typed in CFP, CD46, CD55 or CD59. Conclusions In a case–control sample that has shown the well established associations between AMD and variants in CFH, CFB and C3 there was absence of association with SNPs in CFP, CD46, CD55 and CD59. This suggests that these are not important susceptibility genes for AMD.

Cipriani, Valentina; Matharu, Baljinder K.; Khan, Jane C.; Shahid, Humma; Stanton, Chloe M.; Hayward, Caroline; Wright, Alan F.; Bunce, Catey; Clayton, David G.; Moore, Anthony T.; Yates, John R.W.

2012-01-01

241

Susceptibility to chronic pain following nerve injury is genetically affected by CACNG2  

PubMed Central

Chronic neuropathic pain is affected by specifics of the precipitating neural pathology, psychosocial factors, and by genetic predisposition. Little is known about the identity of predisposing genes. Using an integrative approach, we discovered that CACNG2 significantly affects susceptibility to chronic pain following nerve injury. CACNG2 encodes for stargazin, a protein intimately involved in the trafficking of glutamatergic AMPA receptors. The protein might also be a Ca2+ channel subunit. CACNG2 has previously been implicated in epilepsy. Initially, using two fine-mapping strategies in a mouse model (recombinant progeny testing [RPT] and recombinant inbred segregation test [RIST]), we mapped a pain-related quantitative trait locus (QTL) (Pain1) into a 4.2-Mb interval on chromosome 15. This interval includes 155 genes. Subsequently, bioinformatics and whole-genome microarray expression analysis were used to narrow the list of candidates and ultimately to pinpoint Cacng2 as a likely candidate. Analysis of stargazer mice, a Cacng2 hypomorphic mutant, provided electrophysiological and behavioral evidence for the gene's functional role in pain processing. Finally, we showed that human CACNG2 polymorphisms are associated with chronic pain in a cohort of cancer patients who underwent breast surgery. Our findings provide novel information on the genetic basis of neuropathic pain and new insights into pain physiology that may ultimately enable better treatments.

Nissenbaum, Jonathan; Devor, Marshall; Seltzer, Ze'ev; Gebauer, Mathias; Michaelis, Martin; Tal, Michael; Dorfman, Ruslan; Abitbul-Yarkoni, Merav; Lu, Yan; Elahipanah, Tina; delCanho, Sonia; Minert, Anne; Fried, Kaj; Persson, Anna-Karin; Shpigler, Hagai; Shabo, Erez; Yakir, Benjamin; Pisante, Anne; Darvasi, Ariel

2010-01-01

242

Genetic variation in the DAOA gene complex: Impact on susceptibility for schizophrenia and on cognitive performance  

PubMed Central

Introduction The genetic region coding for D-amino acid oxidase activator (DAOA) is considered an intriguing susceptibility locus for schizophrenia. However, association studies have often resulted in conflicting findings, and the risk conferring variants and their biological impact remain elusive. Our aim in this study was to investigate the relationship between DAOA variation and schizophrenia, and the influence of DAOA on cognitive performance. Methods We analyzed block structure and association patterns of a ~173 kb region on chromosome 13q33, applying genotype data of 55 SNPs derived from Caucasian North American sample (178 cases, 144 healthy controls). Haplotypes were assigned using the program PHASE and frequencies compared between cases and controls. We applied MANOVA to investigate the relationship between the identified risk haplotype on cognitive performance. Results We identified multiple haplotypes within the region containing the DAOA gene. Of these, one was significantly associated with schizophrenia, being over-represented in schizophrenia versus healthy controls. This haplotype was also associated with one aspect of cognitive performance, semantic fluency. Carriers of the risk haplotype showed better semantic fluency than non-carriers. Conclusions We report a significant effect of DAOA variation on risk for schizophrenia. Moreover, we identified a relationship between DAOA genetic variation and specific aspects of neurocognitive function. As the identified DAOA risk haplotype was associated with better performance on a semantic fluency measure, further work is required to identify the mechanism of DAOA action on CNS function, including the possibility of a role for balanced selection at this locus.

Opgen-Rhein, Carolin; Lencz, Todd; Burdick, Katherine E.; Neuhaus, Andres H; DeRosse, Pamela; Goldberg, Terry E.; Malhotra, Anil K.

2008-01-01

243

Genetic Anthropology of the Colorectal Cancer-Susceptibility Allele APC I1307K: Evidence of Genetic Drift within the Ashkenazim  

PubMed Central

The adenomatous polyposis coli (APC) I1307K allele is found in 6% of the Ashkenazi Jewish population and in 1%–2% of Sephardi Jews; it confers a relative risk of 1.5–2.0 for colorectal cancer (CRC) on all carriers. Within the Ashkenazim, the existence of numerous high-prevalence mutations, including I1307K, has sparked controversy over whether genetic drift or selection is the underlying cause. For the present population-based case-control study of CRC in Israel, we tested whether selection has operated at I1307K. We also estimated the age of the I1307K allele, to understand its origin in the context of the Jewish diasporas and subsequent founder events. We genotyped 83 matched pairs, in which one or both members of the pair carried I1307K, at three microsatellites and two SNPs. Haplotypes were statistically constructed using PHASE software. Single-marker age estimates for I1307K were calculated using the approach described by Risch et al. A common progenitor haplotype spanned across APC I1307K from the centromeric marker D5S135 to the telomeric marker D5S346 and was observed in individuals of Ashkenazi, Sephardi, and Arab descent. The ancestor of modern I1307K alleles existed 87.9–118 generations ago (?2,200–2,950 years ago). This age estimate indicates that I1307K existed at about the time of the beginning of the Jewish diaspora, explaining its presence in non-Ashkenazi populations. Our data do not indicate that selection operated at I1307K (D5S346, P=.114; D5S135, P=.373), providing compelling evidence that the high frequency of disease-susceptibility alleles in the Ashkenazim is due to genetic drift, not selection. This research underscores the importance of the migratory patterns of ancestral populations in the ethnic and geographic distribution of APC I1307K.

Niell, Bethany L.; Long, Jeffrey C.; Rennert, Gad; Gruber, Stephen B.

2003-01-01

244

Genetic Background and GxE Interactions Modulate the Penetrance of a Naturally Occurring Wing Mutation in Drosophila melanogaster  

PubMed Central

Many genes involved in producing complex traits are incompletely penetrant. One such example is vesiculated, an X-linked gene in Drosophila melanogaster that results in wing defects. To examine the genetic architecture of a complex trait (wings containing vesicles), we placed a naturally occurring variant into multiple autosomal backgrounds and quantified penetrance and expressivity at a range of developmental temperatures. We found significant epistasis, genotype-by-environment interactions, and maternal effects. Sex and temperature effects were modulated by genetic background. The severity of wing phenotypes also varied across different genetic backgrounds, and expressivity was positively correlated with penetrance. We also found evidence of naturally segregating suppressors of vesiculated. These suppressors were present on both the second and third chromosomes, and complex interactions were observed. Taken together, these findings indicate that multiple genetic and environmental factors modulate the phenotypic effects of a naturally occurring vesiculated allele.

Lachance, Joseph; Jung, Lawrence; True, John R.

2013-01-01

245

Strain-specific nuclear genetic background differentially affects mitochondria-related phenotypes in Saccharomyces cerevisiae  

PubMed Central

In the course of our studies on mitochondrial defects, we have observed important phenotypic variations in Saccharomyces cerevisiae strains suggesting that a better characterization of the genetic variability will be essential to define the relationship between the mitochondrial efficiency and the presence of different nuclear backgrounds. In this manuscript, we have extended the study of such relations by comparing phenotypic assays related to mitochondrial functions of three wild-type laboratory strains. In addition to the phenotypic variability among the wild-type strains, important differences have been observed among strains bearing identical mitochondrial tRNA mutations that could be related only to the different nuclear background of the cells. Results showed that strains exhibited an intrinsic variability in the severity of the effects of the mitochondrial mutations and that specific strains might be used preferentially to evaluate the phenotypic effect of mitochondrial mutations on carbon metabolism, stress responses, and mitochondrial DNA stability. In particular, while W303-1B and MCC123 strains should be used to study the effect of severe mitochondrial tRNA mutations, D273-10B/A1 strain is rather suitable for studying the effects of milder mutations.

Montanari, Arianna; Francisci, Silvia; Fazzi D'Orsi, Mario; Bianchi, Michele Maria

2014-01-01

246

Genetic Background Defines the Regulation of Postnatal Cardiac Growth by 17?-Estradiol Through a ?-Catenin Mechanism.  

PubMed

Estrogen regulates several biological processes in health and disease. Specifically, estrogen exerts antihypertrophic effects in the diseased heart. However, its role in the healthy heart remains elusive. Our initial aim was to identify the effects of 17?-estradiol (E2) on cardiac morphology and global gene expression in the healthy mouse heart. Two-month-old C57BL/6J mice were ovariectomized and treated with E2 or vehicle for 3 months. We report that E2 induced physiological hypertrophic growth in the healthy C57BL/6J mouse heart characterized by an increase in nuclear ?-catenin. Hypothesizing that ?-catenin mediates these effects of E2, we employed a model of cardiac ?-catenin deletion. Our surprising finding is that E2 had the opposite effects in wild-type littermates, which were actually on the C57BL/6N background. Notably, E2 exerted no significant effect in hearts of mice with depleted ?-catenin. We further demonstrate an E2-dependent increase in glycogen synthase kinase 3? (GSK3?) phosphorylation and endosomal markers in C57BL/6J but not C57BL/6N mice. Together, these findings indicate an E2-driven inhibition of GSK3? and consequent activation of ?-catenin in C57BL/6J mice, whereas the opposite occurs in C57BL/6N mice. In conclusion, E2 exerts divergent effects on postnatal cardiac growth in mice with distinct genetic backgrounds modulating members of the GSK3?/?-catenin cascade. PMID:24731099

Kararigas, Georgios; Nguyen, Ba Tiep; Zelarayan, Laura C; Hassenpflug, Maike; Toischer, Karl; Sanchez-Ruderisch, Hugo; Hasenfuss, Gerd; Bergmann, Martin W; Jarry, Hubertus; Regitz-Zagrosek, Vera

2014-07-01

247

Strain-specific nuclear genetic background differentially affects mitochondria-related phenotypes in Saccharomyces cerevisiae.  

PubMed

In the course of our studies on mitochondrial defects, we have observed important phenotypic variations in Saccharomyces cerevisiae strains suggesting that a better characterization of the genetic variability will be essential to define the relationship between the mitochondrial efficiency and the presence of different nuclear backgrounds. In this manuscript, we have extended the study of such relations by comparing phenotypic assays related to mitochondrial functions of three wild-type laboratory strains. In addition to the phenotypic variability among the wild-type strains, important differences have been observed among strains bearing identical mitochondrial tRNA mutations that could be related only to the different nuclear background of the cells. Results showed that strains exhibited an intrinsic variability in the severity of the effects of the mitochondrial mutations and that specific strains might be used preferentially to evaluate the phenotypic effect of mitochondrial mutations on carbon metabolism, stress responses, and mitochondrial DNA stability. In particular, while W303-1B and MCC123 strains should be used to study the effect of severe mitochondrial tRNA mutations, D273-10B/A1 strain is rather suitable for studying the effects of milder mutations. PMID:24700775

Montanari, Arianna; Francisci, Silvia; Fazzi D'Orsi, Mario; Bianchi, Michele Maria

2014-06-01

248

Public interest in predictive genetic testing, including direct-to-consumer testing, for susceptibility to major depression: preliminary findings  

Microsoft Academic Search

The past decade has seen rapid advances in the identification of associations between candidate genes and a range of common multifactorial disorders. This paper evaluates public attitudes towards the complexity of genetic risk prediction in psychiatry involving susceptibility genes, uncertain penetrance and gene–environment interactions on which successful molecular-based mental health interventions will depend. A qualitative approach was taken to enable

Alex Wilde; Bettina Meiser; Philip B Mitchell; Peter R Schofield

2010-01-01

249

Susceptibility of Three Genetic Lines of Chicks to Infection with a Nephropathogenic T Strain of Avian Infectious Bronchitis Virus  

Microsoft Academic Search

Mortality rates were compared in three genetic lines of specific pathogen-free chicks inoculated with one of two doses of a nephropathogenic strain of avian infectious bronchitis (IB) virus. The mortality rates were influenced primarily by the chick strain, but also by age and dose of virus. Chicks of the inbred S line were highly susceptible. After inoculation with a low

J Ignjatovic; R Reece; F Ashton

2003-01-01

250

Genetic susceptibility for human familial essential hypertension in a region of homology with blood pressure linkage on rat chromosome 10  

Microsoft Academic Search

Hypertension is a significant risk factor for heart attack and stroke and represents a major public health burden because of its high prevalence (e.g. 15-20% of the European and American populations). Although blood pressure is known to have a strong genetic determi- nation, the genes responsible for susceptibility to essential hypertension are mostly unknown. Loci involved in blood pressure regulation

Cécile Julier; Marc Delépine; Bernard Keavney; Joseph Terwilliger; S. Davis; Thuan Bui; Xavier Jeunemaître; Gilberto Velho; Philippe Froguel; Peter Ratcliffe; Pierre Corvol; Florent Soubrier; G. Mark Lathrop

1997-01-01

251

A Preliminary Study of Genetic Factors That Influence Susceptibility to Bovine Tuberculosis in the British Cattle Herd  

Microsoft Academic Search

Associations between specific host genes and susceptibility to Mycobacterial infections such as tuberculosis have been reported in several species. Bovine tuberculosis (bTB) impacts greatly the UK cattle industry, yet genetic predispositions have yet to be identified. We therefore used a candidate gene approach to study 384 cattle of which 160 had reacted positively to an antigenic skin test (‘reactors’). Our

Erin E. Driscoll; Joseph I. Hoffman; Laura E. Green; Graham F. Medley; William Amos; Tjeerd Kimman

2011-01-01

252

A QTL for rice grain yield in aerobic environments with large effects in three genetic backgrounds.  

PubMed

A large-effect QTL associated with grain yield in aerobic environments was identified in three genetic backgrounds, Apo/(2)*Swarna, Apo/(2)*IR72, and Vandana/(2)*IR72, using bulk-segregant analysis (BSA). Apo and Vandana are drought-tolerant aerobic-adapted varieties, while Swarna and IR72 are important lowland rice varieties grown on millions of hectares in Asia but perform poorly in aerobic conditions. Two closely linked rice microsatellite (RM) markers, RM510 and RM19367, located on chromosome 6, were found to be associated with yield under aerobic soil conditions in all three backgrounds. The QTL linked to this marker, qDTY6.1 (DTY, grain yield under drought), was mapped to a 2.2 cM region between RM19367 and RM3805 at a peak LOD score of 32 in the Apo/(2)*Swarna population. The effect of qDTY6.1 was tested in a total of 20 hydrological environments over a period of five seasons and in five populations in the three genetic backgrounds. In the Apo/(2)*Swarna population, qDTY6.1 had a large effect on grain yield under favorable aerobic (R (2) ? 66%) and irrigated lowland (R (2) < 39%) conditions but not under drought stress; Apo contributed the favorable allele in all the conditions where an effect was observed. In the Apo/IR72 cross, Apo contributed the favorable allele in almost all the aerobic environments in RIL and BC(1)-derived populations. In the Vandana/IR72 RIL and BC(1)-derived populations, qDTY6.1 had a strong effect on yield in aerobic drought stress, aerobic non-stress, and irrigated lowland conditions; the Vandana allele was favorable in aerobic environments and the IR72 allele was favorable in irrigated lowland environments. We conclude that qDTY6.1 is a large-effect QTL for rice grain yield under aerobic environments and could potentially be used in molecular breeding of rice for aerobic environments. PMID:21938473

Venuprasad, R; Bool, M E; Quiatchon, L; Atlin, G N

2012-02-01

253

Genetic Determinants of UV-Susceptibility in Non-Melanoma Skin Cancer  

PubMed Central

A milieu of cytokines and signaling molecules are involved in the induction of UV-induced immune suppression and thus the etiology of non-melanoma skin cancer (NMSC). Targeting the UV-induced immunosuppression pathway, and using a large population based study of NMSC, we have investigated the risk associated with functional variants in 10 genes (IL10, IL4, IL4R, TNF, TNFR2, HTR2A, HRH2, IL12B, PTGS2, and HAL). The most prominent single genetic effect was observed for IL10. There was increasing risk for both basal cell carcinoma (BCC) and squamous cell carcinoma (SCC) with increasing number of variant IL10 haplotypes (BCC: ptrend?=?0.0048; SCC: ptrend?=?0.031). Having two IL10 GC haplotypes was associated with increased odds ratios of BCC and SCC (ORBCC?=?1.5, 95% CI 1.1–1.9; ORSCC?=?1.4, 95% CI 1.0–1.9), and these associations were largely confined to women (ORBCC?=?2.2, 95% CI 1.4–3.4; SCC: ORSCC?=?1.8, 95% CI 1.1–3.0). To examine how combinations of these variants contribute to risk of BCC and SCC, we used multifactor dimensionality reduction (MDR) and classification and regression trees (CART). Results from both of these methods found that in men, a combination of skin type, burns, IL10, IL4R, and possibly TNFR2 were important in both BCC and SCC. In women, skin type, burns, and IL10 were the most critical risk factors in SCC, with risk of BCC involving these same factors plus genetic variants in HTR2A, IL12B and IL4R. These data suggest differential genetic susceptibility to UV-induced immune suppression and skin cancer risk by gender.

Welsh, Marleen M.; Karagas, Margaret R.; Kuriger, Jacquelyn K.; Houseman, Andres; Spencer, Steven K.; Perry, Ann E.; Nelson, Heather H.

2011-01-01

254

Nutritional status, genetic susceptibility, and insulin resistance--important precedents to atherosclerosis.  

PubMed

Atherosclerosis is a progressive disease that starts early in life and is manifested clinically as coronary artery disease (CAD), cerebrovascular disease, or peripheral artery disease. CAD remains the leading cause of morbidity and mortality in Western society despite the great advances made in understanding its underlying pathophysiology. The key risk factors associated with CAD include hypercholesterolemia, hypertension, poor diet, obesity, age, male gender, smoking, and physical inactivity. Genetics also play an important role that may interact with environmental factors, including diet, nutritional status, and physiological parameters. Furthermore, certain chronic inflammatory conditions also predispose to the development of CAD. The spiraling increase in obesity rates worldwide has made it more pertinent than ever before to understand the metabolic perturbations that link over nutrition to enhanced cardiovascular risk. Great breakthroughs have been made at the pharmacological level to manage CAD; statins and aspirin have revolutionized treatment of CAD and prolonged lifespan. Nonetheless, lifestyle intervention prior to clinical presentation of CAD symptoms would negate/delay the need for chronic pharmacotherapy in at-risk individuals which in turn would relieve healthcare systems of a costly burden. Throughout this review, we debate the relative impact of nutrition versus genetics in driving CAD. We will investigate how overnutrition affects adipose tissue biology and drives IR and will discuss the subsequent implications for the cardiovascular system. Furthermore, we will discuss how lifestyle interventions including diet modification and weight loss can improve both IR and metabolic dyslipidemia that is associated with obesity. We will conclude by delving into the concept that nutritional status interacts with genetic susceptibility, such that perhaps a more personalized nutrition approach may be more effective in determining diet-related risk as well as response to nutritional interventions. PMID:22760984

McGillicuddy, Fiona C; Roche, Helen M

2012-07-01

255

Comparative analysis of genetic background in eight near-isogenic wheat lines with different H genes conferring resistance to Hessian fly.  

PubMed

Near-isogenic lines (NILs) are useful for plant genetic and genomic studies. However, the strength of conclusions from such studies depends on the similarity of the NILs' genetic backgrounds. In this study, we investigated the genetic similarity for a set of NILs developed in the 1990s to study gene-for-gene interactions between wheat (Triticum aestivum L.) and the Hessian fly (Mayetiola destructor (Say)), an important pest of wheat. Each of the eight NILs carries a single H resistance gene and was created by successive backcrossing for two to six generations to susceptible T. aestivum 'Newton'. We generated 256 target region amplification polymorphism (TRAP) markers and used them to calculate genetic similarity, expressed by the Nei and Li (NL) coefficient. Six of the NILs (H3, H5, H6, H9, H11, and H13) had the highly uniform genetic background of Newton, with NL coefficients from 0.97 to 0.99. However, genotypes with H10 or H12 were less similar to Newton, with NL coefficients of 0.86 and 0.93, respectively. Cluster analysis based on NL coefficients and pedigree analysis showed that the genetic similarity between each of the NILs and Newton was affected by both the number of backcrosses and the genetic similarity between Newton and the H gene donors. We thus generated an equation to predict the number of required backcrosses, given varying similarity of donor and recurrent parent. We also investigated whether the genetic residues of the donor parents that remained in the NILs were related to linkage drag. By using a complete set of 'Chinese Spring' nullisomic-tetrasomic lines, one third of the TRAP markers that showed polymorphism between the NILs and Newton were assigned to a specific chromosome. All of the assigned markers were located on chromosomes other than the chromosome carrying the H gene, suggesting that the genetic residues detected in this study were not due to linkage drag. Results will aid in the development and use of near-isogenic lines for studies of the functional genomics of wheat. PMID:21217808

Xu, S S; Chu, C G; Harris, M O; Williams, C E

2011-01-01

256

Genetic variants in the IL1A gene region contribute to intestinal-type gastric carcinoma susceptibility in European populations.  

PubMed

The most studied genetic susceptibility factors involved in gastric carcinoma (GC) risk are polymorphisms in the inflammation-linked genes interleukin 1 (IL1) B and IL1RN. Despite the evidence pointing to the IL1 region, definite functional variants reproducible across populations of different genetic background have not been discovered so far. A high density linkage disequilibrium (LD) map of the IL1 gene cluster was established using HapMap to identify haplotype tagSNPs. Eighty-seven SNPs were genotyped in a Portuguese case-control study (358 cases, 1,485 controls) for the discovery analysis. A replication study, including a subset of those tagSNPs (43), was performed in an independent analysis (EPIC-EurGast) containing individuals from 10 European countries (365 cases, 1284 controls). Single SNP and haplotype block associations were determined for GC overall and anatomopathological subtypes. The most robust association was observed for SNP rs17042407, 16Kb upstream of the IL1A gene. Although several other SNP associations were observed, only the inverse association of rs17042407 allele C with GC of the intestinal type was observed in both studies, retaining significance after multiple testing correction (p?=?0.0042) in the combined analysis. The haplotype analysis of the IL1A LD block in the combined dataset revealed the association between a common haplotype carrying the rs17042407 variant and GC, particularly of the intestinal type (p?=?3.1 × 10(-5) ) and non cardia localisation (p?=?4.6 × 10(-3) ). These results confirm the association of IL1 gene variants with GC and reveal a novel SNP and haplotypes in the IL1A region associated with intestinal type GC in European populations. PMID:24615437

Durães, Cecília; Muñoz, Xavier; Bonet, Catalina; García, Nadia; Venceslá, Adoración; Carneiro, Fátima; Peleteiro, Bárbara; Lunet, Nuno; Barros, Henrique; Lindkvist, Björn; Boutron-Ruault, Marie-Christine; Bueno-de-Mesquita, H B As; Rizzato, Cosmeri; Trichopoulou, Antonia; Weiderpass, Elisabete; Naccarati, Allessio; Travis, Ruth C; Tjønneland, Anne; Gurrea, Aurelio Barricarte; Johansson, Mattias; Riboli, Elio; Figueiredo, Céu; González, Carlos Alberto; Capellà, Gabriel; Machado, José Carlos; Sala, Núria

2014-09-15

257

Genetic Susceptibility Factors on Genes Involved in the Steroid Hormone Biosynthesis Pathway and Progesterone Receptor for Gastric Cancer Risk  

PubMed Central

Background The objective of the study was to investigate the role of genes (HSD3B1, CYP17A1, CYP19A1, HSD17B2, HSD17B1) involved in the steroid hormone biosynthesis pathway and progesterone receptor (PGR) in the etiology of gastric cancer in a population-based two-phase genetic association study. Methods In the discovery phase, 108 candidate SNPs in the steroid hormone biosynthesis pathway related genes and PGR were analyzed in 76 gastric cancer cases and 322 controls in the Korean Multi-Center Cancer Cohort. Statistically significant SNPs identified in the discovery phase were re-evaluated in an extended set of 386 cases and 348 controls. Pooled- and meta-analyses were conducted to summarize the results. Results Of the 108 SNPs in steroid hormone biosynthesis pathway related genes and PGR analyzed in the discovery phase, 23 SNPs in PGR in the recessive model and 10 SNPs in CYP19A1 in the recessive or additive models were significantly associated with increased gastric cancer risk (p<0.05). The minor allele frequencies of the SNPs in both the discovery and extension phases were not statistically different. Pooled- and meta-analyses showed CYP19A1 rs1004982, rs16964228, and rs1902580 had an increased risk for gastric cancer (pooled OR [95% CI]?=?1.22 [1.01–1.48], 1.31 [1.03–1.66], 3.03 [1.12–8.18], respectively). In contrast, all PGR SNPs were not statistically significantly associated with gastric cancer risk. Conclusions Our findings suggest CYP19A1 that codes aromatase may play an important role in the association of gastric cancer risk and be a genetic marker for gastric cancer susceptibility.

Cho, Lisa Y.; Yang, Jae Jeong; Ko, Kwang-Pil; Ma, Seung Hyun; Shin, Aesun; Choi, Bo Youl; Han, Dong Soo; Song, Kyu Sang; Kim, Yong Sung; Chang, Soung-Hoon; Shin, Hai-Rim; Kang, Daehee; Yoo, Keun-Young; Park, Sue K.

2012-01-01

258

Role of genetic heterogeneity and epistasis in bladder cancer susceptibility and outcome: a learning classifier system approach  

PubMed Central

Background and objective Detecting complex patterns of association between genetic or environmental risk factors and disease risk has become an important target for epidemiological research. In particular, strategies that provide multifactor interactions or heterogeneous patterns of association can offer new insights into association studies for which traditional analytic tools have had limited success. Materials and methods To concurrently examine these phenomena, previous work has successfully considered the application of learning classifier systems (LCSs), a flexible class of evolutionary algorithms that distributes learned associations over a population of rules. Subsequent work dealt with the inherent problems of knowledge discovery and interpretation within these algorithms, allowing for the characterization of heterogeneous patterns of association. Whereas these previous advancements were evaluated using complex simulation studies, this study applied these collective works to a ‘real-world’ genetic epidemiology study of bladder cancer susceptibility. Results and discussion We replicated the identification of previously characterized factors that modify bladder cancer risk—namely, single nucleotide polymorphisms from a DNA repair gene, and smoking. Furthermore, we identified potentially heterogeneous groups of subjects characterized by distinct patterns of association. Cox proportional hazard models comparing clinical outcome variables between the cases of the two largest groups yielded a significant, meaningful difference in survival time in years (survivorship). A marginally significant difference in recurrence time was also noted. These results support the hypothesis that an LCS approach can offer greater insight into complex patterns of association. Conclusions This methodology appears to be well suited to the dissection of disease heterogeneity, a key component in the advancement of personalized medicine.

Urbanowicz, Ryan John; Andrew, Angeline S; Karagas, Margaret Rita; Moore, Jason H

2013-01-01

259

Evaluation of genetic susceptibility to childhood allergy and asthma in an African American urban population  

Microsoft Academic Search

Background  Asthma and allergy represent complex phenotypes, which disproportionately burden ethnic minorities in the United States. Strong\\u000a evidence for genomic factors predisposing subjects to asthma\\/allergy is available. However, methods to utilize this information\\u000a to identify high risk groups are variable and replication of genetic associations in African Americans is warranted.\\u000a \\u000a \\u000a \\u000a \\u000a Methods  We evaluated 41 single nucleotide polymorphisms (SNP) and a deletion corresponding

Bonnie R Joubert; David M Reif; Stephen W Edwards; Kevin A Leiner; Edward E Hudgens; Peter Egeghy; Jane E Gallagher; Elaine Cohen Hubal

2011-01-01

260

Eimeria Species and Genetic Background Influence the Serum Protein Profile of Broilers with Coccidiosis  

PubMed Central

Background Coccidiosis is an intestinal disease caused by protozoal parasites of the genus Eimeria. Despite the advent of anti-coccidial drugs and vaccines, the disease continues to result in substantial annual economic losses to the poultry industry. There is still much unknown about the host response to infection and to date there are no reports of protein profiles in the blood of Eimeria-infected animals. The objective of this study was to evaluate the serum proteome of two genetic lines of broiler chickens after infection with one of three species of Eimeria. Methodology/Principal Findings Birds from lines A and B were either not infected or inoculated with sporulated oocysts from one of the three Eimeria strains at 15 d post-hatch. At 21 d (6 d post-infection), whole blood was collected and lesion scoring was performed. Serum was harvested and used for 2-dimensional gel electrophoresis. A total of 1,266 spots were quantitatively assessed by densitometry. Protein spots showing a significant effect of coccidia strain and/or broiler genetic line on density at P<0.05?0.01 (250 spots), P<0.01?0.001 (248 spots), and P<0.001 (314 spots) were excised and analyzed by matrix-assisted laser desorption/ionization tandem time-of-flight mass spectrometry. Proteins were identified in 172 spots. A total of 46 different proteins were identified. Of the spots with a corresponding protein identification, 57 showed a main effect of coccidia infection and/or 2-way interaction of coccidia infection×broiler genetic line at P<0.001. Conclusions/Significance Several of the metabolic enzymes identified in this study are potential candidates for early diagnostic markers of E. acervulina infection including malate dehydrogenase 2, NADH dehydrogenase 1 alpha subcomplex 9, and an ATP synthase. These proteins were detected only in Line A birds that were inoculated with E. acervulina. Results from this study provide a basic framework for future research aimed at uncovering the complex biochemical mechanisms involved in host response to Eimeria infection and in identifying molecular targets for diagnostic screening and development of alternative preventative and therapeutic methods.

Gilbert, Elizabeth R.; Cox, Chasity M.; Williams, Patricia M.; McElroy, Audrey P.; Dalloul, Rami A.; Ray, W. Keith; Barri, Adriana; Emmerson, Derek A.; Wong, Eric A.; Webb, Kenneth E.

2011-01-01

261

Host Genetic Background Impacts Disease Outcome During Intrauterine Infection with Ureaplasma parvum  

PubMed Central

Ureaplasma parvum, an opportunistic pathogen of the human urogenital tract, has been implicated in contributing to chorioamnionitis, fetal morbidity, and fetal mortality. It has been proposed that the host genetic background is a critical factor in adverse pregnancy outcome as sequela to U. parvum intra-amniotic infection. To test this hypothesis we assessed the impact of intrauterine U. parvum infection in the prototypical TH1/M1 C57BL/6 and TH2/M2 BALB/c mouse strain. Sterile medium or U. parvum was inoculated into each uterine horn and animals were evaluated for intra-amniotic infection, fetal infection, chorioamnionitis and fetal pathology at 72 hours post-inoculation. Disease outcome was assessed by microbial culture, in situ detection of U. parvum in fetal and utero-placental tissues, grading of chorioamnionitis, and placental gene expression of IL-1?, IL-1?, IL-6, TNF-?, S100A8, and S100A9. Placental infection and colonization rates were equivalent in both strains. The in situ distribution of U. parvum in placental tissues was also similar. However, a significantly greater proportion of BALB/c fetuses were infected (P<0.02). C57BL/6 infected animals predominantly exhibited mild to moderate chorioamnionitis (P<0.0001), and a significant reduction in placental expression of IL-1?, IL-1?, IL-6, TNF-?, S100A8, and S100A9 compared to sham controls (P<0.02). Conversely, severe protracted chorioamnionitis with cellular necrosis was the predominant lesion phenotype in BALB/c mice, which also exhibited a significant increase in placental expression of IL-1?, IL-1?, IL-6, TNF-?, S100A8, and S100A9 (P<0.01). Fetal pathology in BALB/c was multi-organ and included brain, lung, heart, liver, and intestine, whereas fetal pathology in C57BL/6 was only detected in the liver and intestines. These results confirm that the host genetic background is a major determinant in ureaplasmal induced chorioamnionitis with fetal infection and fetal inflammatory response.

von Chamier, Maria; Allam, Ayman; Brown, Mary B.; Reinhard, Mary K.; Reyes, Leticia

2012-01-01

262

Cytogenetic effects from exposure to mixed pesticides and the influence from genetic susceptibility.  

PubMed Central

Exposure to pesticides remains a major environmental health problem. Health risk from such exposure needs to be more precisely understood. We conducted three different cytogenetic assays to elucidate the biological effects of exposure to mixed pesticides in 20 Costa Rica farmers (all nonsmokers) compared with 20 matched controls. The farmers were also exposed to dibromochloropropane during the early employment years, and most of them experienced sterility/fertility problems. Our data show that the farmers had consistently higher frequencies of chromosome aberrations, as determined by the standard chromosome aberration assay, and significantly abnormal DNA repair responses (p < 0.05), as determined by the challenge assay, but no statistically significant differences in the tandem-probe fluorescence in situ hybridization (FISH) assay (p > 0.05). Genotype analysis indicates that farmers with certain "unfavorable" versions of polymorphic metabolizing genes (cytochrome P4502E1, the glutathione S-transferases mu and theta, and the paraoxonase genes) had significantly more biological effects, as determined by all three cytogenetic assays, than both the farmers with the "favorable" alleles and the matched controls. A unique observation is that, in individuals who had inherited any of the mentioned "unfavorable" alleles, farmers were consistently underrepresented. In conclusion, the Costa Rican farmers were exposed to genotoxic agents, most likely pesticides, which expressed the induction of biological and adverse health effects. The farmers who had inherited "unfavorable" metabolizing alleles were more susceptible to genotoxic effects than those with "favorable" alleles. Our genotype data suggest that the well-recognized "healthy worker effect" may be influenced by unrecognized occupational selection pressure against genetically susceptible individuals. Images Figure 1

Au, W W; Sierra-Torres, C H; Cajas-Salazar, N; Shipp, B K; Legator, M S

1999-01-01

263

Dietary Omega-3 Fatty Acids, Other Fat Intake, Genetic Susceptibility and Progression to Incident Geographic Atrophy  

PubMed Central

Objective To investigate associations between dietary omega-3 fatty acids and other fat intake, genes related to age-related macular degeneration (AMD) and progression to geographic atrophy (GA). Design Observational analysis of a prospective cohort. Participants 2531 individuals from the Age-Related Eye Disease Study, among which 525 eyes progressed to GA and 4165 eyes did not. Methods Eyes without advanced AMD (GA or neovascular disease) at baseline were evaluated for progression to GA. Behavioral data, including smoking and body mass index measurements were collected at baseline using questionnaires. Dietary data was collected from food frequency questionnaires (FFQ) at baseline. Dietary fats, including omega-3 fatty acids (docosahexaenoic acid or DHA and eicosapentaenoic acid or EPA), omega-6 fatty acids, monounsaturated, saturated, polyunsaturated and total fat were sex and calorie adjusted and divided into quintiles. Eight single nucleotide polymorphisms (SNPs) in 7 genes: CFH, ARMS2/HTRA1, CFB, C2, C3, CFI, LIPC were genotyped. Cox proportional hazards models were used to test for associations between incident GA and intake of dietary lipids, and interaction effects between dietary fat intake and genetic variation on risk of GA. Main Outcome Measures Associations between dietary fat intake reported from FFQs, genetic variants and incident GA. Results Increased intake of DHA was significantly associated with reduced risk of progression to GA in multivariate models with behavioral factors (Model A) and behavioral factors with genetic variants (Model B) (P-trend=0.008 and 0.03, respectively). Total omega-3 long chain polyunsaturated (DHA + EPA) fatty acid intake was significantly associated with reduced risk of progression in Model B variants (P-trend =0.02). Monounsaturated fat was associated with increased risk in Model A (P=0.05).. DHA intake in the 5th quintile was significantly associated with reduced risk of incident GA among those with the ARMS2/HTRA1 homozygous risk genotype (HR = 0.4, P = 0.002, P – interaction between gene and fat intake = 0.05), whereas DHA was not associated with reduced risk of GA among those with the homozygous non-risk genotype (HR = 1.0, P= 0.90). Conclusions Increased self- reported dietary intake of omega-3 fatty acids is associated with reduced risk of GA and may modify genetic susceptibility for progression to GA.

Reynolds, Robyn; Rosner, Bernard; Seddon, Johanna M.

2013-01-01

264

Genetic susceptibility of the donor kidney contributes to the development of renal damage after syngeneic transplantation.  

PubMed

Solitary kidneys, especially in rats, appear vulnerable to develop functional and structural damage. However, differences in susceptibility exist between strains. It is not clear whether this is intrinsic to the kidney or due to environmental factors. Therefore, the aim of the present study was to investigate possible differences in genetic susceptibility for renal damage. By transplanting different rat donor kidneys into a normotensive, histocompatible recipient, the kidneys were exposed to the same blood pressure profiles, metabolic and hormonal environment. Kidneys from young adult hypertensive fawn-hooded (FHH) rats, a strain showing early onset renal damage, normotensive, renal damage-resistant August x Copenhagen-Irish (ACI), and (ACI x FHH) F1 donors were transplanted into male F1 recipients. The native kidneys of the recipients were removed 1 week after transplantation. The results were mutually compared and to their unilaterally nephrectomized littermates. Systolic blood pressure (SBP) and albuminuria (UaV) were determined at the time of transplantation and at 8 and 16 weeks. The histomorphologic analysis included the incidence of focal glomerulosclerosis (FGS), and determination of chronic transplant dysfunction according to the BANFF criteria. A negative impact of the transplantation technique in this syngeneic situation could not be detected as F1 transplants did not differ functionally and morphologically from their UNx controls. Transplanting an ACI kidney did not result in significant changes of SBP, UaV, and incidence of FGS compared to F1 transplants and ACI-UNx. In contrast, FHH kidneys did show a progressive increase of UaV and glomerulosclerosis and a significantly higher BANFF score, whereas the SBP did not differ from F1 transplants. The moderate hypertension seen in FHH did not travel with the kidney. Compared to the FHH-UNx rats, transplantation of a FHH kidney did significantly attenuate the increase of UaV and FGS. The susceptibility of the donor kidney appears to be an important factor in the development of chronic renal damage. This may play a role in the long-term functional changes seen after clinical renal transplantation. PMID:10371370

Kouwenhoven, E A; van Dokkum, R P; Marquet, R L; Heemann, U W; de Bruin, R W; IJzermans, J N; Provoost, A P

1999-06-01

265

Behavioral deficits in an Angelman syndrome model: Effects of genetic background and age  

PubMed Central

Angelman syndrome (AS) is a severe neurodevelopmental disorder associated with disruption of maternally inherited UBE3A (ubiquitin protein ligase E3A) expression. At the present time, there is no effective treatment for AS. Mouse lines with loss of maternal Ube3a (Ube3am–/p+) recapitulate multiple aspects of the clinical AS profile, including impaired motor coordination, learning deficits, and seizures. Thus, these genetic mouse models could serve as behavioral screens for preclinical efficacy testing, a critical component of drug discovery for AS intervention. However, the severity and consistency of abnormal phenotypes reported in Ube3am–/p+ mice can vary, dependent upon age and background strain, which is problematic for the detection of beneficial drug effects. As part of an ongoing AS drug discovery initiative, we characterized Ube3am–/p+ mice on either a 129S7/SvEvBrd-Hprtb-m2 (129) or C57BL/6J (B6) background across a range of functional domains and ages to identify reproducible and sufficiently large phenotypes suitable for screening therapeutic compounds. The results from the study showed that Ube3am–/p+ mice have significant deficits in acquisition and reversal learning in the Morris water maze. The findings also demonstrated that Ube3am–/p+ mice exhibit motor impairment in a rotarod task, hypoactivity, reduced rearing and marble-burying, and deficient fear conditioning. Overall, these profiles of abnormal phenotypes can provide behavioral targets for evaluating effects of novel therapeutic strategies relevant to AS.

Huang, Hsien-Sung; Burns, Andrew J.; Nonneman, Randal J.; Baker, Lorinda K.; Riddick, Natallia V.; Nikolova, Viktoriya D.; Riday, Thorfinn T.; Yashiro, Koji; Philpot, Benjamin D.; Moy, Sheryl S.

2013-01-01

266

The connexin43-dependent transcriptome during brain development: Importance of genetic background  

PubMed Central

Use of null mutant mice is a powerful way to evaluate the role of specific proteins in brain function. Studies performed on knockout mice have revealed some unexpected roles of the gap junction proteins (connexins). Thus, analyses of gene expression in connexin43 (Cx43) null brains indicated that deletion of a single gene (Gja1) induced expression level change of numerous other genes located on all chromosomes and involved in a wide diversity of functional pathways. The significant overlap between alterations in gene expression level, control and coordination in Cx43 knockout and knockdown astrocytes raised the possibility that Gja1 represents a transcriptomic node of gene regulatory networks. However, conditional deletion of Gja1 in astrocytes of two mouse strains resulted in remarkably different phenotypes. In order to evaluate the influence of the genetic background on the transcriptome, we performed microarray studies on brains of GFAP-Cre:Cx43f/f C57Bl/6 and 129/SVEV mice. The surprisingly low number of Cx43 core genes (regulated in all Cx43 nulls regardless of strain) and the high number of differently regulated genes in the two Cx43 conditional knockouts indicate high influence of mouse strain on brain transcriptome.

Iacobas, S; Iacobas, DA; Spray, DC; Scemes, E

2012-01-01

267

Ogg1 genetic background determines the genotoxic potential of environmentally relevant arsenic exposures.  

PubMed

Inorganic arsenic (i-As) is a well-established human carcinogen to which millions of people are exposed worldwide. It is generally accepted that the genotoxic effects of i-As after an acute exposure are partially linked to the i-As-induced production of reactive oxygen species, but it is necessary to better determine whether chronic sub-toxic i-As doses are able to induce biologically significant levels of oxidative DNA damage (ODD). To fill in this gap, we have tested the genotoxic and oxidative effects of environmentally relevant arsenic exposures using mouse embryonic fibroblast MEF mutant Ogg1 cells and their wild-type counterparts. Effects were examined by using the comet assay complemented with the use of FPG enzyme. Our findings indicate that MEF Ogg1-/- cells are more sensitive to arsenite-induced acute toxicity, genotoxicity and ODD. Long-term exposure to sub-toxic doses of arsenite generates a detectable increase in ODD and genotoxic DNA damage only in MEF Ogg1-deficient cells. Altogether, the data presented here point out the relevance of ODD and Ogg1 genetic background on the genotoxic risk of i-As at environmentally plausible doses. The persistent accumulation of DNA 8-OH-dG lesions in Ogg1-/- cells during the complete course of the exposure suggests a relevant role in arsenic-associated carcinogenic risk in turn. PMID:24190502

Bach, Jordi; Sampayo-Reyes, Adriana; Marcos, Ricard; Hernández, Alba

2014-03-01

268

Genetics and Biomarkers of Moyamoya Disease: Significance of RNF213 as a Susceptibility Gene.  

PubMed

Moyamoya disease is characterized by a progressive stenosis at the terminal portion of the internal carotid artery and an abnormal vascular network at the base of the brain. Although its etiology is still unknown, recent genome-wide and locus-specific association studies identified RNF213 as an important susceptibility gene of moyamoya disease among East Asian population. A polymorphism in c.14576G>A in RNF213 was identified in 95% of familial patients with moyamoya disease and 79% of sporadic cases, and patients having this polymorphism were found to have significantly earlier disease onset and a more severe form of moyamoya disease, such as the presentation of cerebral infarction and posterior cerebral artery stenosis. The exact mechanism by which the RNF213 abnormality relates to moyamoya disease remains unknown, while recent reports using genetically engineered mice lacking RNF213 by homologous recombination provide new insight for the pathogenesis of this rare entity. Regarding biomarkers of moyamoya disease, moyamoya disease is characterized by an increased expression of angiogenic factors and pro-inflammatory molecules such as vascular endothelial growth factors and matrix metalloproteinase-9, which may partly explain its clinical manifestations of the pathologic angiogenesis, spontaneous hemorrhage, and higher incidence of cerebral hyperperfusion after revascularization surgery. More recently, blockade of these pro-inflammatory molecules during perioperative period is attempted to reduce the potential risk of surgical complication including cerebral hyperperfusion syndrome. In this review article, we focus on the genetics and biomarkers of moyamoya disease, and sought to discuss their clinical implication. PMID:24949311

Fujimura, Miki; Sonobe, Shinya; Nishijima, Yasuo; Niizuma, Kuniyasu; Sakata, Hiroyuki; Kure, Shigeo; Tominaga, Teiji

2014-05-01

269

Identification of New Genetic Susceptibility Loci for Breast Cancer Through Consideration of Gene-Environment Interactions  

PubMed Central

Genes that alter disease risk only in combination with certain environmental exposures may not be detected in genetic association analysis. By using methods accounting for gene-environment (G × E) interaction, we aimed to identify novel genetic loci associated with breast cancer risk. Up to 34,475 cases and 34,786 controls of European ancestry from up to 23 studies in the Breast Cancer Association Consortium were included. Overall, 71,527 single nucleotide polymorphisms (SNPs), enriched for association with breast cancer, were tested for interaction with 10 environmental risk factors using three recently proposed hybrid methods and a joint test of association and interaction. Analyses were adjusted for age, study, population stratification, and confounding factors as applicable. Three SNPs in two independent loci showed statistically significant association: SNPs rs10483028 and rs2242714 in perfect linkage disequilibrium on chromosome 21 and rs12197388 in ARID1B on chromosome 6. While rs12197388 was identified using the joint test with parity and with age at menarche (P-values = 3 × 10?07), the variants on chromosome 21 q22.12, which showed interaction with adult body mass index (BMI) in 8,891 postmenopausal women, were identified by all methods applied. SNP rs10483028 was associated with breast cancer in women with a BMI below 25 kg/m2 (OR = 1.26, 95% CI 1.15–1.38) but not in women with a BMI of 30 kg/m2 or higher (OR = 0.89, 95% CI 0.72–1.11, P for interaction = 3.2 × 10?05). Our findings confirm comparable power of the recent methods for detecting G × E interaction and the utility of using G × E interaction analyses to identify new susceptibility loci.

Schoeps, Anja; Rudolph, Anja; Seibold, Petra; Dunning, Alison M.; Milne, Roger L.; Bojesen, Stig E.; Swerdlow, Anthony; Andrulis, Irene; Brenner, Hermann; Behrens, Sabine; Orr, Nicholas; Jones, Michael; Ashworth, Alan; Li, Jingmei; Cramp, Helen; Connley, Dan; Czene, Kamila; Darabi, Hatef; Chanock, Stephen J.; Lissowska, Jolanta; Figueroa, Jonine D.; Knight, Julia; Glendon, Gord; Mulligan, Anna M.; Dumont, Martine; Severi, Gianluca; Baglietto, Laura; Olson, Janet; Vachon, Celine; Purrington, Kristen; Moisse, Matthieu; Neven, Patrick; Wildiers, Hans; Spurdle, Amanda; Kosma, Veli-Matti; Kataja, Vesa; Hartikainen, Jaana M.; Hamann, Ute; Ko, Yon-Dschun; Dieffenbach, Aida K.; Arndt, Volker; Stegmaier, Christa; Malats, Nuria; Arias Perez, JoseI.; Benitez, Javier; Flyger, Henrik; Nordestgaard, B?rge G.; Truong, Therese; Cordina-Duverger, Emilie; Menegaux, Florence; Silva, Isabel dos Santos; Fletcher, Olivia; Johnson, Nichola; Haberle, Lothar; Beckmann, Matthias W.; Ekici, Arif B.; Braaf, Linde; Atsma, Femke; van den Broek, Alexandra J.; Makalic, Enes; Schmidt, Daniel F.; Southey, Melissa C.; Cox, Angela; Simard, Jacques; Giles, Graham G.; Lambrechts, Diether; Mannermaa, Arto; Brauch, Hiltrud; Guenel, Pascal; Peto, Julian; Fasching, Peter A.; Hopper, John; Flesch-Janys, Dieter; Couch, Fergus; Chenevix-Trench, Georgia; Pharoah, Paul D. P.; Garcia-Closas, Montserrat; Schmidt, Marjanka K.; Hall, Per; Easton, Douglas F.; Chang-Claude, Jenny

2014-01-01

270

Telomere length homeostasis and telomere position effect on a linear human artificial chromosome are dictated by the genetic background  

PubMed Central

Telomere position effect (TPE) is the influence of telomeres on subtelomeric epigenetic marks and gene expression. Previous studies suggested that TPE depends on genetic background. As these analyses were performed on different chromosomes, cell types and species, it remains unclear whether TPE represents a chromosome—rather than genetic background-specific regulation. We describe the development of a Linear Human Artificial Chromosome (L-HAC) as a new tool for telomere studies. The L-HAC was generated through the Cre-loxP-mediated addition of telomere ends to an existing circular HAC (C-HAC). As it can be transferred to genetically distinct cell lines and animal models the L-HAC enables the study of TPE in an unprecedented manner. The HAC was relocated to four telomerase-positive cell lines via microcell-mediated chromosome transfer and subsequently to mice via blastocyst injection of L-HAC+-ES-cells. We could show consistent genetic background-dependent adaptation of telomere length and telomere-associated de novo subtelomeric DNA methylation in mouse ES-R1 cells as well as in mice. Expression of the subtelomeric neomycin gene was inversely correlated with telomere length and subtelomeric methylation. We thus provide a new tool for functional telomere studies and provide strong evidence that telomere length, subtelomeric chromatin marks and expression of subtelomeric genes are genetic background dependent.

Weuts, An; Voet, Thierry; Verbeeck, Jelle; Lambrechts, Nathalie; Wirix, Evelyne; Schoonjans, Luc; Danloy, Sophie; Marynen, Peter; Froyen, Guy

2012-01-01

271

Genome-wide analysis of genetic susceptibility to language impairment in an isolated Chilean population  

PubMed Central

Specific language impairment (SLI) is an unexpected deficit in the acquisition of language skills and affects between 5 and 8% of pre-school children. Despite its prevalence and high heritability, our understanding of the aetiology of this disorder is only emerging. In this paper, we apply genome-wide techniques to investigate an isolated Chilean population who exhibit an increased frequency of SLI. Loss of heterozygosity (LOH) mapping and parametric and non-parametric linkage analyses indicate that complex genetic factors are likely to underlie susceptibility to SLI in this population. Across all analyses performed, the most consistently implicated locus was on chromosome 7q. This locus achieved highly significant linkage under all three non-parametric models (max NPL=6.73, P=4.0 × 10?11). In addition, it yielded a HLOD of 1.24 in the recessive parametric linkage analyses and contained a segment that was homozygous in two affected individuals. Further, investigation of this region identified a two-SNP haplotype that occurs at an increased frequency in language-impaired individuals (P=0.008). We hypothesise that the linkage regions identified here, in particular that on chromosome 7, may contain variants that underlie the high prevalence of SLI observed in this isolated population and may be of relevance to other populations affected by language impairments.

Villanueva, Pia; Newbury, Dianne F; Jara, Lilian; De Barbieri, Zulema; Mirza, Ghazala; Palomino, Hernan M; Fernandez, Maria Angelica; Cazier, Jean-Baptiste; Monaco, Anthony P; Palomino, Hernan

2011-01-01

272

HLA-A*31 as a marker of genetic susceptibility to sepsis  

PubMed Central

Objective The HLA haplotype has been associated with many autoimmune diseases, but no associations have been described in sepsis. This study aims to investigate the HLA system as a possible marker of genetic sepsis susceptibility. Methods This is a prospective cohort study including patients admitted to an intensive care unit and healthy controls from a list of renal transplant donors. Patients with less 18 years of age; pregnant or HIV positive patients; those with metastatic malignancies or receiving chemotherapy; or with advanced liver disease; or with end-of-life conditions were excluded. The DNA was extracted from the whole blood and HLA haplotypes determined using MiliPlex® technology. Results From October 2010 to October 2012, 1,121 patients were included (1,078 kidney donors, 20 patients admitted with severe sepsis and 23 with septic shock). HLA-A*31 positive subjects had increased risk of developing sepsis (OR 2.36, 95%CI 1.26-5.35). Considering a p value <0.01, no other significant association was identified. Conclusion HLA-A*31 expression is associated to risk of developing sepsis.

da Silva, Fabiano Pinheiro; Preuhs Filho, Germano; Finger, Eduardo; Barbeiro, Hermes Vieira; Zampieri, Fernando Godinho; Goulart, Alessandra Carvalho; Torggler Filho, Francisco; Panajotopoulos, Nicolas; Velasco, Irineu Tadeu; Kalil, Jorge; de Souza, Heraldo Possolo; da Cruz Neto, Luiz Monteiro; Rodrigues, Helcio

2013-01-01

273

Evaluation of BRCA2 in the genetic susceptibility of familial esophageal cancer.  

PubMed

Previous studies of esophageal squamous cell carcinoma (ESCC) have shown a high frequency of allelic loss on chromosome 13q, infrequent somatic mutations in BRCA2, and a suggested association between a positive family history (FH+) of upper gastrointestinal cancer and germline BRCA2 mutations. In all, 70 ESCC patients (44 FH+ and 26 FH-) were examined by direct full sequencing of germline DNA for BRCA2 mutations. In addition, 28 family members of three of these patients and 232 unrelated healthy blood bank donor controls were examined for the mutations identified in the 70 ESCC patients. Five BRCA2 germline mutations, including three not previously reported (N1600del, A2054P, and V2109I), were identified in six of 44 FH+ patients, but none of 26 FH- patients (14 vs 0%, P=0.078), consistent with our previous findings (3/34 or 9% FH+ vs 0/22 or 0% FH-, P=0.27). The cumulative frequency of BRCA2 germline mutations in ESCC patients in this and our previous study combined is 12%, with all mutations found in FH+ as opposed to FH- cases (9/78 or 12% FH+ vs 0/48 or 0% FH-, P=0.013). We conclude that germline mutations in BRCA2 in ESCC patients from this high-risk area of China are more frequent in FH+ than FH- cases, suggesting that BRCA2 may play a role in genetic susceptibility to familial ESCC. PMID:14647438

Hu, Nan; Wang, Chaoyu; Han, Xiao-You; He, Li-Ji; Tang, Ze-Zhong; Giffen, Carol; Emmert-Buck, Michael R; Goldstein, Alisa M; Taylor, Philip R

2004-01-22

274

A systematic mammalian genetic interaction map reveals pathways underlying ricin susceptibility.  

PubMed

Genetic interaction (GI) maps, comprising pairwise measures of how strongly the function of one gene depends on the presence of a second, have enabled the systematic exploration of gene function in microorganisms. Here, we present a two-stage strategy to construct high-density GI maps in mammalian cells. First, we use ultracomplex pooled shRNA libraries (25 shRNAs/gene) to identify high-confidence hit genes for a given phenotype and effective shRNAs. We then construct double-shRNA libraries from these to systematically measure GIs between hits. A GI map focused on ricin susceptibility broadly recapitulates known pathways and provides many unexpected insights. These include a noncanonical role for COPI, a previously uncharacterized protein complex affecting toxin clearance, a specialized role for the ribosomal protein RPS25, and functionally distinct mammalian TRAPP complexes. The ability to rapidly generate mammalian GI maps provides a potentially transformative tool for defining gene function and designing combination therapies based on synergistic pairs. PMID:23394947

Bassik, Michael C; Kampmann, Martin; Lebbink, Robert Jan; Wang, Shuyi; Hein, Marco Y; Poser, Ina; Weibezahn, Jimena; Horlbeck, Max A; Chen, Siyuan; Mann, Matthias; Hyman, Anthony A; Leproust, Emily M; McManus, Michael T; Weissman, Jonathan S

2013-02-14

275

Fine-mapping of breast cancer susceptibility loci characterizes genetic risk in African Americans  

PubMed Central

Genome-wide association studies (GWAS) have revealed 19 common genetic variants that are associated with breast cancer risk. Testing of the index signals found through GWAS and fine-mapping of each locus in diverse populations will be necessary for characterizing the role of these risk regions in contributing to inherited susceptibility. In this large study of breast cancer in African-American women (3016 cases and 2745 controls), we tested the 19 known risk variants identified by GWAS and replicated associations (P < 0.05) with only 4 variants. Through fine-mapping, we identified markers in four regions that better capture the association with breast cancer risk in African Americans as defined by the index signal (2q35, 5q11, 10q26 and 19p13). We also identified statistically significant associations with markers in four separate regions (8q24, 10q22, 11q13 and 16q12) that are independent of the index signals and may represent putative novel risk variants. In aggregate, the more informative markers found in the study enhance the association of these risk regions with breast cancer in African Americans [per allele odds ratio (OR) = 1.18, P = 2.8 × 10?24 versus OR = 1.04, P = 6.1 × 10?5]. In this detailed analysis of the known breast cancer risk loci, we have validated and improved upon markers of risk that better characterize their association with breast cancer in women of African ancestry.

Chen, Fang; Chen, Gary K.; Millikan, Robert C.; John, Esther M.; Ambrosone, Christine B.; Bernstein, Leslie; Zheng, Wei; Hu, Jennifer J.; Ziegler, Regina G.; Deming, Sandra L.; Bandera, Elisa V.; Nyante, Sarah; Palmer, Julie R.; Rebbeck, Timothy R.; Ingles, Sue A.; Press, Michael F.; Rodriguez-Gil, Jorge L.; Chanock, Stephen J.; Le Marchand, Loic; Kolonel, Laurence N.; Henderson, Brian E.; Stram, Daniel O.; Haiman, Christopher A.

2011-01-01

276

[Genetics and susceptibility to human papillomaviruses: epidermodysplasia verruciformis, a disease model].  

PubMed

The outcomes of infection by human papillomaviruses (HPV), both oncogenic and non oncogenic, show major interindividual variability The underlying genetic factors and mechanisms are poorly known, but their complexity is illustrated by epidermodysplasia verruciformis (EV), a rare autosomal recessive genodermatosis associated with a high risk of non melanoma skin cancer. This model disease is characterized by abnormal susceptibility to widespread betapapillomaviruses, including HPV-5, a virus associated with EV cancers. Most cases of EV are caused by a mutation that inactivates either of two related genes, EVER1 and EVER2. This inactivation likely compensates for the absence of a viral gene (E5 or E8) essential for HPV pathogenicity. Proteins E5 and E8 interfere with the interaction between EVER proteins and ZnT1, a zinc transporter EV is thus likely to represent a primary defect of intrinsic (constitutive) immunity or innate immunity to betapapillomaviruses, involving modulation of zinc homeostasis upon keratinocyte infection. It remains to be established which cellular genes are involved in intrinsic, innate or acquired immune responses to other human papillomaviruses, including oncogenic genital types. PMID:21513129

Orth, Gérard

2010-06-01

277

Contribution of LPHN3 to the genetic susceptibility to ADHD in adulthood: a replication study.  

PubMed

Attention-deficit/hyperactivity disorder (ADHD) is a common and highly heritable developmental disorder characterized by a persistent impairing pattern of inattention and/or hyperactivity-impulsivity. Using families from a genetic isolate, the Paisa population from Colombia, and five independent datasets from four different populations (United States, Germany, Norway and Spain), a highly consistent association was recently reported between ADHD and the latrophilin 3 (LPHN3) gene, a brain-specific member of the LPHN subfamily of G-protein-coupled receptors that is expressed in ADHD-related regions, such as amygdala, caudate nucleus, cerebellum and cerebral cortex. To replicate the association between LPHN3 and ADHD in adults, we undertook a case-control association study in 334 adult patients with ADHD and 334 controls with 43 single nucleotide polymorphisms (SNPs) covering the LPNH3 gene. Single- and multiple-marker analyses showed additional evidence of association between LPHN3 and combined type ADHD in adulthood [P = 0.0019; df = 1; odds ratio (OR) = 1.82 (1.25-2.70) and P = 5.1e-05; df = 1; OR = 2.25 (1.52-3.34), respectively]. These results further support the LPHN3 contribution to combined type ADHD, and specifically to the persistent form of the disorder, and point at this new neuronal pathway as a common susceptibility factor for ADHD throughout the lifespan. PMID:21040458

Ribasés, M; Ramos-Quiroga, J A; Sánchez-Mora, C; Bosch, R; Richarte, V; Palomar, G; Gastaminza, X; Bielsa, A; Arcos-Burgos, M; Muenke, M; Castellanos, F X; Cormand, B; Bayés, M; Casas, M

2011-03-01

278

HIV type 1 genetic diversity and genotypic drug susceptibility in the Republic of Moldova.  

PubMed

HIV-1 genetic diversity and, for the first time, genotypic drug susceptibility was investigated for strains circulating in the Republic of Moldova (of the former Soviet Union). Eighty-three samples from adults recently infected by intravenous drug use (IDU) (n = 60), heterosexual contact (n = 8), and from blood donors (n = 15) that tested positive from 1997 to 1998, and originating from different regions of Moldova were serotyped. By group-specific and subtype-specific peptide ELISA, patients were infected by serotype A (n = 65), serotype B (n = 1), or were nontypable (n = 17). Heteroduplex mobility assay (HMA) confirmed 11 subtype A and the one subtype B infection. Analyses of pol and env sequences for six of the IDUs confirmed that they were infected with subtype A strain. These strains clustered tightly with subtype A strains isolated from the former Soviet Union in phylogenetic analysis. No mutations associated with drug resistance were detected. The Republic of Moldova is culturally more closely related to Romania (where subtype F dominates the epidemic), but depends economically on Russia (where subtype A is established among IDUs). Thus, our results suggest that the spread of HIV in this region is driven by drug networks rather than being due to cultural similarities. PMID:11559431

Pandrea, I; Descamps, D; Collin, G; Robertson, D L; Damond, F; Dimitrienco, V; Gheorghita, S; Pecec, M; Simon, F; Brun-Vézinet, F; Apetrei, C

2001-09-01

279

A Systematic Mammalian Genetic Interaction Map Reveals Pathways Underlying Ricin Susceptibility  

PubMed Central

SUMMARY Genetic interaction (GI) maps, comprising pairwise measures of how strongly the function of one gene depends on the presence of a second, have enabled the systematic exploration of gene function in microorganisms. Here, we present a two-stage strategy to construct high-density GI maps in mammalian cells. First, we use ultra-complex pooled shRNA libraries (25 shRNAs/gene) to identify high-confidence hit genes for a given phenotype and effective shRNAs. We then construct double-shRNA libraries from these to systematically measure GIs between hits. A GI map focused on ricin susceptibility broadly recapitulates known pathways and provides many unexpected insights. These include a non-canonical role for COPI, a novel protein complex (SRIC) affecting toxin clearance, a specialized role for the ribosomal protein RPS25, and functionally distinct mammalian TRAPP complexes. The ability to rapidly generate mammalian GI maps provides a potentially transformative tool for defining gene function and designing combination therapies based on synergistic pairs.

Bassik, Michael C.; Kampmann, Martin; Lebbink, Robert Jan; Wang, Shuyi; Hein, Marco Y.; Poser, Ina; Weibezahn, Jimena; Horlbeck, Max A.; Chen, Siyuan; Mann, Matthias; Hyman, Anthony A.; LeProust, Emily M.; McManus, Michael T.; Weissman, Jonathan S.

2013-01-01

280

Fowl immunoglobulins: quantitation and antibody activity during Marek's disease in genetically resistant and susceptible birds.  

PubMed

Five-week-old birds of resistant (N) and susceptible (P) genetic lines were inoculated with the JM strain of Marek's disease (MD) virus. MD occurred only in P-line birds; one-third had died by the end of the experiment (63 days after inoculation). Sera were examined for antibodies (precipitating, virus neutralizing,and fluorescing), and immunoglobulins were measured. Antibodies were associated with immunoglobulin classes by density gradient centrifugation and utilization of specific antisera to gowl immunoglobulins in indirect immunofluorescence. Precipitating antibodies were found in both lines; they first appeared 7 days after inoculation in P-line birds and 14 days after inoculation in N-line birds, but thereafter there was no difference between the two genetic lines. A peak of neutralizing antibody occurred in both lines between 6 and 12 days. Thereafter neutralizing antibodies increased gradually throughout the experiment. Neutralizing antibody levels were at this stage often higher in N-line than in P-line birds. The fluorescent antibody test showed transient immunoglobulin (Ig) M antibody from 7 to 9 days in N-line birds and 5 to 12 days in P-line birds; this corresponded with the initial peak of neutralizing antibody. Antibodies were seen from 7 to 8 days after inoculation and increased gradually durin gthe experiment, generally paralleling the secondary increase in neutralizing antibodies. Ultracentrifugation confirmed the presence of IgM and IgG antibodies as described. Antibodies of the IgA class were not found. The alterations in serum immunoglobulin levels occurred in three phrases: (i) 1 to 9 days postinfection, there was an increase in IgM and IgA compared with uninfected control birds; (ii) 10 to 20 days postinfection, Ig M and IgA levels were lower than in control birds; and (iii) 21 days postinfection, until the end of experiment, IgA returned to normal levels, IgG increased to about eight times higher than in control birds, and IgM in P-line birds returned to normal levels and in N-line birds reached and maintained levels about double those of control birds. Another experiment was designed to examine the separate effects of moving and inoculation of uninfected kidney cells and virus-infected kidney cells. The changes in immunoglobulins observed in the first experiment occurred only after infection with MD virus and were not related to movement or handling stress. It was concluded that no significant primary difference exists in the humoral immune system between fowls resistant and susceptible to MD; all differences could be related to the immunosuppressive effects of MD, which are greater in susceptible birds apparently due to the greater lymphoid tissue damage in these strains. PMID:803923

Higgins, D A; Calnek, B W

1975-01-01

281

Genetic control of Trichomonas vaginalis infection. I. Resistance or susceptibility among different mouse strains.  

PubMed

Susceptibility of different strains of mice to infection with Trichomonas vaginalis was determined. Striking strain differences in susceptibility to T. vaginalis inoculum were observed in different mouse strains suggesting that susceptibility is under control of genes mapping mainly outside the major histocompatibility complex. PMID:552834

Landolfo, S; Martinotti, M G; Martinetto, P; Forni, G

1979-03-31

282

The Physiological Effects of Deleting the Mouse Slc30a8 Gene Encoding Zinc Transporter-8 Are Influenced by Gender and Genetic Background  

PubMed Central

Objective The SLC30A8 gene encodes the islet-specific transporter ZnT-8, which is hypothesized to provide zinc for insulin-crystal formation. A polymorphic variant in SLC30A8 is associated with altered susceptibility to type 2 diabetes. Several groups have examined the effect of global Slc30a8 gene deletion but the results have been highly variable, perhaps due to the mixed 129SvEv/C57BL/6J genetic background of the mice studied. We therefore sought to remove the conflicting effect of 129SvEv-specific modifier genes. Methods The impact of Slc30a8 deletion was examined in the context of the pure C57BL/6J genetic background. Results Male C57BL/6J Slc30a8 knockout (KO) mice had normal fasting insulin levels and no change in glucose-stimulated insulin secretion (GSIS) from isolated islets in marked contrast to the ?50% and ?35% decrease, respectively, in both parameters observed in male mixed genetic background Slc30a8 KO mice. This observation suggests that 129SvEv-specific modifier genes modulate the impact of Slc30a8 deletion. In contrast, female C57BL/6J Slc30a8 KO mice had reduced (?20%) fasting insulin levels, though this was not associated with a change in fasting blood glucose (FBG), or GSIS from isolated islets. This observation indicates that gender also modulates the impact of Slc30a8 deletion, though the physiological explanation as to why impaired insulin secretion is not accompanied by elevated FBG is unclear. Neither male nor female C57BL/6J Slc30a8 KO mice showed impaired glucose tolerance. Conclusions Our data suggest that, despite a marked reduction in islet zinc content, the absence of ZnT-8 does not have a substantial impact on mouse physiology.

Pound, Lynley D.; Sarkar, Suparna A.; Ustione, Alessandro; Dadi, Prasanna K.; Shadoan, Melanie K.; Lee, Catherine E.; Walters, Jay A.; Shiota, Masakazu; McGuinness, Owen P.; Jacobson, David A.; Piston, David W.; Hutton, John C.; Powell, David R.; O'Brien, Richard M.

2012-01-01

283

Prevalence, genetic diversity, and antimicrobial susceptibility profiles of Staphylococcus aureus isolated from bovine mastitis in Zhejiang Province, China  

Microsoft Academic Search

This study was conducted to determine genetic diversity and antimicrobial susceptibility profiles of Staphylococcus aureus recovered from bovine mastitis in Zhejiang Province, China. Out of 3178 quarter milk samples from 846 lactating cows, among\\u000a which 459 cows (54.3%) were found HMT positive, 890 quarters (28%) were found having subclinical mastitis. From 75 representative\\u000a S. aureus isolates, 16 distinct types were

Jian-ping Li; Hai-jian Zhou; Lin Yuan; Ting He; Song-hua Hu

2009-01-01

284

Meta-analysis of genetic association studies supports a contribution of common variants to susceptibility to common disease  

Microsoft Academic Search

Association studies offer a potentially powerful approach to identify genetic variants that influence susceptibility to com- mon disease1-4, but are plagued by the impression that they are not consistently reproducible5,6. In principle, the inconsis- tency may be due to false positive studies, false negative stud- ies or true variability in association among different populations4-8. The critical question is whether false

Kirk E. Lohmueller; Celeste L. Pearce; Malcolm Pike; Eric S. Lander; Joel N. Hirschhorn

2003-01-01

285

Original Article Genetic variants of the XRCC1 gene and susceptibility to esophageal cancer: a meta-analysis  

Microsoft Academic Search

To summarize published data on the role of common genetic variants of the X-ray repair cross- complementing group 1 (XRCC1) gene in susceptibility to esophageal cancer (EC), we performed a meta-analysis including 11 eligible publications with 3,306 patients and 6,852 controls for Arg399Gln and 832 patients and 1,418 controls for Arg194Trp. Overall, the variant Gln399 allele was not associated with

Ming Yin; Dongfeng Tan; Qingyi Wei

2009-01-01

286

Background and objectives of the workshop: Ecological Risk Assessment for the Gene Flow from the Genetically Modified Crops  

Microsoft Academic Search

The objectives of this workshop is to discuss information that the present situation of the research on the gene flow from genetically modified (GM) crops, particularly for rice and soybean which are important crops in Asia. This workshop targets setting the background for more in depth discussion on ecological risk assessment for GM rice and soybean cultivations by identifying key

Kazuhito Matsuo

287

The Conditional Nature of Genetic Interactions: The Consequences of Wild-Type Backgrounds on Mutational Interactions in a Genome-Wide Modifier Screen  

PubMed Central

The phenotypic outcome of a mutation cannot be simply mapped onto the underlying DNA variant. Instead, the phenotype is a function of the allele, the genetic background in which it occurs and the environment where the mutational effects are expressed. While the influence of genetic background on the expressivity of individual mutations is recognized, its consequences on the interactions between genes, or the genetic network they form, is largely unknown. The description of genetic networks is essential for much of biology; yet if, and how, the topologies of such networks are influenced by background is unknown. Furthermore, a comprehensive examination of the background dependent nature of genetic interactions may lead to identification of novel modifiers of biological processes. Previous work in Drosophila melanogaster demonstrated that wild-type genetic background influences the effects of an allele of scalloped (sd), with respect to both its principal consequence on wing development and its interactions with a mutation in optomotor blind. In this study we address whether the background dependence of mutational interactions is a general property of genetic systems by performing a genome wide dominant modifier screen of the sdE3 allele in two wild-type genetic backgrounds using molecularly defined deletions. We demonstrate that ?74% of all modifiers of the sdE3 phenotype are background-dependent due in part to differential sensitivity to genetic perturbation. These background dependent interactions include some with qualitative differences in the phenotypic outcome, as well as instances of sign epistasis. This suggests that genetic interactions are often contingent on genetic background, with flexibility in genetic networks due to segregating variation in populations. Such background dependent effects can substantially alter conclusions about how genes influence biological processes, the potential for genetic screens in alternative wild-type backgrounds identifying new loci that contribute to trait expression, and the inferences of the topology of genetic networks.

Chari, Sudarshan; Dworkin, Ian

2013-01-01

288

Participation in Breast Cancer Genetic Counseling: The Influence of Educational Level, Ethnic Background, and Risk Perception  

Microsoft Academic Search

Genetic counseling has been suggested as a means of providing information and support to women with a family history of breast cancer. Yet women who undergo cancer genetic counseling in the United States generally consist of only a subset of those at risk, namely well-educated, upper-middle class, European American and Jewish women. We report outcomes from a study that provided

Julie Culver; Wylie Burke; Yutaka Yasui; Sharon Durfy

2001-01-01

289

Birth Order and Narcolepsy Risk Among Genetically Susceptible Individuals: a Population-based Case-control Study  

PubMed Central

Background Birth order may play a role in autoimmune diseases and early childhood infections, both factors implicated in the etiology of narcolepsy. We investigated the association between birth order and narcolepsy risk in a population-based case-control study in which all study subjects were HLA-DQB1*0602 positive. Methods Subjects were 18-50 years old, residents of King County, Washington, and positive for HLA-DQB1*0602. Birth order was obtained from administered interviews. We used logistic regression to generate odds ratios adjusted for income and African American race. Results Analyses included 67 cases (mean age 34.3 [SD=9.1], 70.2% female) and 95 controls (mean age 35.1 [SD=8.8], 58.1% female). Associations for birth order were as follows: First born (cases 38.8% vs. controls 50.2%, OR=1.0; Reference), second born (cases 29.9% vs. controls 32.9%, OR=1.6; 95% CI 0.7, 3.7), third born or higher (cases 31.3% vs. controls 16.8%, OR=2.5; 95% CI 1.0, 6.0). A linear trend was significant (p<0.05). Sibling number, sibling gender, having children, and number of children did not differ significantly between narcolepsy cases and controls. Conclusions Narcolepsy risk was significantly associated with higher birth order in this population-based study of genetically susceptible individuals. This finding supports an environmental influence on narcolepsy risk through an autoimmune mechanism, early childhood infections, or both.

Watson, Nathaniel F.; Ton, Thanh G.N.; Koepsell, Thomas D.; Longstreth, W.T.

2011-01-01

290

HLA-B*1301 as a Biomarker for Genetic Susceptibility to Hypersensitivity Dermatitis Induced by Trichloroethylene among Workers in China  

PubMed Central

Background Trichloroethylene (TCE) is used extensively as an industrial solvent and has been recognized as one of the major environmental pollutants. To date, > 200 cases of TCE-induced hypersensitivity dermatitis among exposed workers have been reported worldwide, and TCE exposure has become one of the critical occupational health issues in Asia. Objectives The study aimed to identify genetic susceptible biomarkers associated with the TCE-induced hypersensitivity dermatitis in genes located in the human leukocyte antigen (HLA) region. Methods From 1998 to 2006, 121 cases with TCE-induced hypersensitivity dermatitis and 142 tolerant controls were recruited into the population-based case–control study. We determined HLA alleles B, DRB1, DQA1, and DQB1, by sequence-based typing. p-Values were corrected for comparisons of multiple HLA alleles. In addition, we compared and analyzed the structure character of amino acid residues of HLA molecules found in participants. Results We obtained complete genotyping data of 113 cases and 142 controls. The allele HLA-B*1301 was present in 83 (73.5%) of 113 patients compared with 13 (9.2%) of 142 tolerant workers (odds ratio = 27.5; 95% confidence interval, 13.5–55.7; corrected p = 1.48 × 10?21). In addition, the HLA-B*44 alleles were present in 6.2% (7/113) of patients, but were absent in TCE-tolerant workers. Residue 95 shared by HLA-B*1301 and HLA-B*44 molecules formed a different pocket F than other residues. Conclusions The allele HLA-B*1301 is strongly associated with TCE-induced hypersensitivity dermatitis among exposed workers and might be used as a biomarker to predict high risk individuals to TCE.

Li, Haishan; Dai, Yufei; Huang, Hanlin; Li, Laiyu; Leng, Shuguang; Cheng, Juan; Niu, Yong; Duan, Huawei; Liu, Qingjun; Zhang, Xing; Huang, Xianqing; Xie, Jinxin; Feng, Zhiming; Wang, Juncai; He, Jiaxi; Zheng, Yuxin

2007-01-01

291

High-fat diet-induced obesity exacerbates inflammatory bowel disease in genetically susceptible Mdr1a-/- male mice.  

PubMed

Obesity is a chronic inflammatory disease and a risk factor for disorders such as heart disease, diabetes, and cancer. A high-fat diet (HFD), a risk factor for obesity, has also been associated with inflammatory bowel disease (IBD). A proinflammatory state characterized by systemic and local increases in cytokine and chemokine levels are noted in both obesity and IBD, but it is unclear whether obesity is a risk factor for IBD. To examine any association between obesity and IBD, we chose FVB.129P2- Abcb1a(tm1Bor)N7 (Mdr1a(-/-)) mice, because this strain develops IBD spontaneously with age without a chemical or bacterial "trigger." In addition, its background strain, FVB, has been used for diet-induced obesity studies. Mdr1a(-/-) mice and wild-type (WT) mice were fed a HFD (?60% calories from fat) or a low-fat diet (LFD; ?11% calories from fat) for 12 wk. Obesity phenotypes examined included body weight measurements, glucose metabolism changes, and adiposity at termination of the study. IBD was determined by clinical signs, necropsy, and histopathology. We found that compared with those fed the LFD, both the Mdr1a(-/-) and WT mice fed the HFD had greater weight gains and elevated plasma leptin concentrations (P < 0.0001). When all mice were analyzed, weight gain was also associated with inflammation in mesenteric fat (R(2) = 0.5; P < 0.0001) and mesenteric lymph nodes (R(2) = 0.4; P < 0.0001). In contrast, the HFD was not associated with IBD in WT mice, whereas it exacerbated spontaneous IBD in Mdr1a(-/-) mice (P = 0.012; Fisher's exact test). Although a HFD and obesity were not associated with IBD in WT mice, our studies suggest that they are likely risk factors for IBD in a genetically susceptible host, such as Mdr1a(-/-) mice. PMID:23761644

Paik, Jisun; Fierce, Yvette; Treuting, Piper M; Brabb, Thea; Maggio-Price, Lillian

2013-08-01

292

The relationship between genetic variability and the susceptibility of Biomphalaria alexandrina snails to Schistosoma mansoni infection.  

PubMed

In the present study, Biomphalaria snails collected from five Egyptian governorates (Giza, Fayoum, Kafr El-Sheikh, Ismailia and Damietta), as well as reference control Biomphalaria alexandrina snails from the Schistosome Biological Supply Center (SBSC) (Theodor Bilharz Research Institute, Egypt), were subjected to species-specific polymerase chain reaction (PCR) assays to identify the collected species. All of the collected snails were found to be B. alexandrina and there was no evidence of the presence of Biomphalaria glabrata. Randomly amplified polymorphic DNA (RAPD)-PCR assays showed different fingerprints with varying numbers of bands for the first generation (F?) of B. alexandrina snail populations (SBSC, Giza, Fayoum, Kafr El-Sheikh, Ismailia and Damietta). The primer OPA-1 produced the highest level of polymorphism and amplified the greatest number of specific bands. The estimated similarity coefficients among the B. alexandrina populations based on the RAPD-PCR profiles ranged from 0.56 (between SBSC and Ismailia snails) to 0.72 (between Ismailia and Kafr El-Sheikh snails). Experimental infection of the F? of progeny from the collected snails with Schistosoma mansoni (SBSC strain) showed variable susceptibility rates ranging from 15% in the Fayoum snail group to 50.3% in SBSC snails. A negative correlation was observed between the infection rates in the different snail groups and the distances separating their corresponding governorates from the parasite source. The infection rates of the snail groups and their similarity coefficients with SBSC B. alexandrina snails were positively correlated. The variations in the rates of infection of different B. alexandrina groups with S. mansoni, as well as the differences in the similarity coefficients among these snails, are dependent not only on the geographical distribution of the snails and the parasite, but also on the genetic variability of the snails. Introduction of this variability into endemic areas may reduce the ability of the parasite to infect local hosts and consequently reduce schistosomiasis epidemiology. PMID:22510827

Mohamed, Azza H; El-Din, Ahmed T Sharaf; Mohamed, Ahmed M; Habib, Mohamed R

2012-05-01

293

Genetic variants in inflammation pathway genes and asthma in glioma susceptibility.  

PubMed

Single nucleotide polymorphisms (SNPs) in inflammation-related genes have previously been shown to alter risks of developing various cancers. However, the effects of such SNPs on glioma risk remain unclear. We used a multistrategic approach to elucidate the relationship between glioma risk, asthma/allergies, and 23 literature-based functional SNPs in 11 inflammation genes. Genotyping was conducted on 373 histologically confirmed adult glioma patients and 365 cancer-free controls from the Harris County Brain Tumor Study. Deviations from the Hardy-Weinberg equilibrium were assessed using the chi(2)-test, and Akaike's information criterion was used to determine the best genetic model for each SNP. Odds ratios (ORs) were calculated both for each SNP individually and for grouped analyses, examining the effects of the numbers of adverse alleles on glioma risk in participants with and without asthma. In the single-locus analysis of the 23 examined SNPs, 1 pro-inflammatory and 2 anti-inflammatory gene SNPs were significantly associated with glioma risk (COX2/PTGS2, rs20417 [OR = 1.41]; IL10, rs1800896 [OR = 1.57]; and IL13, rs20541 [OR = 0.39], respectively). When we examined the joint effects of the risk-conferring alleles of these 3 SNPs, we found a significant trend indicating that the risk increases as the number of adverse alleles increase (P = .005). Stratifying by asthma status, we found that this dose-response-like trend of increasing risk is only present among those without asthma/allergies (P < .0001). Our study indicates that polymorphisms in inflammation genes are associated with glioma susceptibility, especially when a history of asthma/allergies is absent. PMID:20406895

Amirian, E; Liu, Yanhong; Scheurer, Michael E; El-Zein, Randa; Gilbert, Mark R; Bondy, Melissa L

2010-05-01

294

Genetic variants in inflammation pathway genes and asthma in glioma susceptibility  

PubMed Central

Single nucleotide polymorphisms (SNPs) in inflammation-related genes have previously been shown to alter risks of developing various cancers. However, the effects of such SNPs on glioma risk remain unclear. We used a multistrategic approach to elucidate the relationship between glioma risk, asthma/allergies, and 23 literature-based functional SNPs in 11 inflammation genes. Genotyping was conducted on 373 histologically confirmed adult glioma patients and 365 cancer-free controls from the Harris County Brain Tumor Study. Deviations from the Hardy–Weinberg equilibrium were assessed using the ?2-test, and Akaike's information criterion was used to determine the best genetic model for each SNP. Odds ratios (ORs) were calculated both for each SNP individually and for grouped analyses, examining the effects of the numbers of adverse alleles on glioma risk in participants with and without asthma. In the single-locus analysis of the 23 examined SNPs, 1 pro-inflammatory and 2 anti-inflammatory gene SNPs were significantly associated with glioma risk (COX2/PTGS2, rs20417 [OR = 1.41]; IL10, rs1800896 [OR = 1.57]; and IL13, rs20541 [OR = 0.39], respectively). When we examined the joint effects of the risk-conferring alleles of these 3 SNPs, we found a significant trend indicating that the risk increases as the number of adverse alleles increase (P = .005). Stratifying by asthma status, we found that this dose–response-like trend of increasing risk is only present among those without asthma/allergies (P < .0001). Our study indicates that polymorphisms in inflammation genes are associated with glioma susceptibility, especially when a history of asthma/allergies is absent.

Amirian, E.; Liu, Yanhong; Scheurer, Michael E.; El-Zein, Randa; Gilbert, Mark R.; Bondy, Melissa L.

2010-01-01

295

Recent Advances in the Characterization of Genetic Factors Involved in Human Susceptibility to Infection by Schistosomiasis  

PubMed Central

Human resistance to infection by schistosomes is associated to a strong Th2 immune. However a persistent Th2 response can cause severe kidney and liver disease in human. In this review, we mainly focused on the control of infection levels caused by schistosomes. Several experimental models allowed us to better understand the immunological mechanisms of the host against schistosome infection. High IgE and eosinophil levels are associated with resistance to infection by schistosomes and this effect is counterbalanced by IgG4. IgE and eosinophils are highly dependent on IL-4, IL-13, and Il-5, which are three main Th2 cytokines. We also examined the genetic factors involved in human susceptibility to infection by schistosomiasis. Infection levels are mainly regulated by a major locus SM1, in 5q31-q33 region, which contains the genes encoding for the IL-4, IL-13, and Il-5 cytokines. An association between an IL13 polymorphism, rs1800925, and infection levels has been shown. This polymorphism synergistically acts with another polymorphism (rs324013) in the STAT6 gene, encoding for the signal transducer of the IL13 pathway. This pathway has also been involved in atopic disorders. As helminthiasis, atopy is the result of aberrant Th2 cytokine response to allergens, with an increased production of IL-4, IL-13, Il-9 and Il-5, with high amounts of allergen-specific and total IgE and eosinophilia. However, the Th2 immune response is protective in helminthiasis but aggravating in atopic disorders. Several studies reported interplay between helminthic infections and allergic reactions. The different results are discussed here.

Isnard, Amandine; Chevillard, Christophe

2008-01-01

296

Phosphodiesterase 11A (PDE11A) Genetic Variants May Increase Susceptibility to Prostatic Cancer  

PubMed Central

Context: Among the genomic loci harboring potential candidate genes for prostatic cancer (PCa) is the 2q31-33 chromosomal region that harbors the gene encoding phosphodiesterase 11A (PDE11A). In addition, the combined cancer genome expression metaanalysis datasets included PDE11A among the top 1% down-regulated genes in PCa. Objective: In the present study, we screened 50 unrelated PCa patients of Brazilian descent for PDE11A coding defects. Design: The study consisted of PDE11A sequencing, in vitro functional assays, and immunostaining analysis. Results: We identified eight different sequence alterations in 15 patients (30%): one stop-codon and seven missense mutations. Three of the variants (R202C, Y658C, and E840K) were novel, and the remaining five (Y727C, R804H, R867G, M878V, and R307X) have been associated with predisposition to adrenal or testicular tumors. The overall prevalence of PDE11A-inactivating sequence variants among PCa patients was significantly higher than in 287 healthy controls (0.16 vs. 0.051, respectively, P < 0.001, odds ratio 3.81, 95% confidence interval 1.86–7.81) and the R202C, Y658C, and E840K substitutions were not found in controls. All missense mutations led to decreased PDE11A activity in human embryonic kidney 293 and PC3M cells and immunostaining of PCa samples with sequence changes showed decreased PDE11A protein expression. Conclusion: Our data suggest that, like in the adrenal cortex and the testicular germ cells, PDE11A-inactivating genetic alterations may play a role in susceptibility to PCa.

Faucz, Fabio Rueda; Horvath, Anelia; Rothenbuhler, Anya; Almeida, Madson Q.; Libe, Rossella; Raffin-Sanson, Marie-Laure; Bertherat, Jerome; Carraro, Dirce Maria; Soares, Fernando Augusto; de Campos Molina, Gustavo; Campos, Antonio H.; Alexandre, Rodrigo B.; Bendhack, Marcelo Luiz; Nesterova, Maria; Stratakis, Constantine A.

2011-01-01

297

Vegetables- and antioxidant-related nutrients, genetic susceptibility, and non-Hodgkin lymphoma risk  

PubMed Central

Genetic susceptibility to DNA oxidation, carcinogen metabolism, and altered DNA repair may increase non-Hodgkin lymphoma (NHL) risk, whereas vegetables-and antioxidant-related nutrients may decrease risk. We evaluated the interaction of a priori-defined dietary factors with 28 polymorphisms in these metabolic pathways. Incident cases (n = 1,141) were identified during 1998–2000 from four cancer registries and frequency-matched to population-based controls (n = 949). We estimated diet-gene joint effects using two-phase semi-parametric maximum-likelihood methods, which utilized genotype data from all subjects as well as 371 cases and 311 controls with available diet information. Adjusted odds ratios (95% confidence intervals) were lower among common allele carriers with higher dietary intakes. For the GSTM3 3-base insertion and higher total vegetable intake, the risk was 0.56 (0.35–0.92, p interaction = 0.03); for GSTP1 A114V and higher cruciferous vegetable intake, the risk was 0.52 (0.34–0.81, p interaction = 0.02); for OGG1 S326C and higher daily zinc intake, the risk was 0.71 (0.47–1.08, p interaction = 0.04) and for XRCC3 T241M and higher green leafy vegetable intake, the risk was 0.63 (0.41–0.97, p interaction = 0.03). Calculation of the false positive report probability determined a high likelihood of falsely positive associations. Although most associations have not been examined previously with NHL, our results suggest the examined polymorphisms are not modifiers of the association between vegetable and zinc intakes and NHL risk.

Kelemen, Linda E.; Wang, Sophia S.; Lim, Unhee; Cozen, Wendy; Schenk, Maryjean; Hartge, Patricia; Li, Yan; Rothman, Nathaniel; Davis, Scott; Chanock, Stephen J.; Ward, Mary H.

2009-01-01

298

Genetic Variants on 3q21 and in the Sp8 Transcription Factor Gene (SP8) as Susceptibility Loci for Psychotic Disorders: A Genetic Association Study  

PubMed Central

Background Recent genome-wide association studies (GWASs) investigating bipolar disorder (BD) have detected a number of susceptibility genes. These studies have also provided novel insight into shared genetic components between BD and schizophrenia (SCZ), two major psychotic disorders. To examine the replication of the risk variants for BD and the pleiotropic effect of the variants associated with BD, we conducted a genetic association study of single nucleotide polymorphisms (SNPs) that were selected based upon previous BD GWASs, which targeted psychotic disorders (BD and SCZ) in the Japanese population. Methods Forty-eight SNPs were selected based upon previous GWASs. A two-stage analysis was conducted using first-set screening (for all SNPs: BD?=?1,012, SCZ?=?1,032 and control?=?993) and second-set replication samples (for significant SNPs in the screening analysis: BD?=?821, SCZ?=?1,808 and control?=?2,149). We assessed allelic association between BD, SCZ, psychosis (BD+SCZ) and the SNPs selected for the analysis. Results Eight SNPs revealed nominal association signals for all comparisons (Puncorrected<0.05). Among these SNPs, the top two SNPs (associated with psychosis: Pcorrected?=?0.048 and 0.037 for rs2251219 and rs2709722, respectively) were further assessed in the second-set samples, and we replicated the signals from the initial screening analysis (associated with psychosis: Pcorrected?=?0.0070 and 0.033 for rs2251219 and rs2709722, respectively). The meta-analysis between the current and previous GWAS results showed that rs2251219 in Polybromo1 (PBRM1) was significant on genome-wide association level (P?=?5×10?8) only for BD (P?=?9.4×10?9) and psychosis (P?=?2.0×10?10). Although the association of rs2709722 in Sp8 transcription factor (SP8) was suggestive in the Asian population (P?=?2.1×10?7 for psychosis), this signal weakened when the samples size was increased by including data from a Caucasian population (P?=?4.3×10?3). Conclusions We found 3p21.1 (including PBRM1, strong linkage disequilibrium made it difficult to pinpoint the risk genes) and SP8 as risk loci for BD, SCZ and psychosis. Further replication studies will be required for conclusive results.

Kondo, Kenji; Ikeda, Masashi; Kajio, Yusuke; Saito, Takeo; Iwayama, Yoshimi; Aleksic, Branko; Yamada, Kazuo; Toyota, Tomoko; Hattori, Eiji; Ujike, Hiroshi; Inada, Toshiya; Kunugi, Hiroshi; Kato, Tadafumi; Yoshikawa, Takeo; Ozaki, Norio; Iwata, Nakao

2013-01-01

299

Genetic variation in SIRT1 affects susceptibility of lung squamous cell carcinomas in former uranium miners from the Colorado plateau  

PubMed Central

Epidemiological studies of underground miners suggested that occupational exposure to radon causes lung cancer with squamous cell carcinoma (SCC) as the predominant histological type. However, the genetic determinants for susceptibility of radon-induced SCC in miners are unclear. Double-strand breaks induced by radioactive radon daughters are repaired primarily by non-homologous end joining (NHEJ) that is accompanied by the dynamic changes in surrounding chromatin, including nucleosome repositioning and histone modifications. Thus, a molecular epidemiological study was conducted to assess whether genetic variation in 16 genes involved in NHEJ and related histone modification affected susceptibility for SCC in radon-exposed former miners (267 SCC cases and 383 controls) from the Colorado plateau. A global association between genetic variation in the haplotype block where SIRT1 resides and the risk for SCC in miners (P = 0.003) was identified. Haplotype alleles tagged by the A allele of SIRT1 rs7097008 were associated with increased risk for SCC (odds ratio = 1.69, P = 8.2×10?5) and greater survival in SCC cases (hazard ratio = 0.79, P = 0.03) in miners. Functional validation of rs7097008 demonstrated that the A allele was associated with reduced gene expression in bronchial epithelial cells and compromised DNA repair capacity in peripheral lymphocytes. Together, these findings substantiate genetic variation in SIRT1 as a risk modifier for developing SCC in miners and suggest that SIRT1 may also play a tumor suppressor role in radon-induced cancer in miners.

Belinsky, Steven A.

2013-01-01

300

Genetic variations in the KIR gene family may contribute to susceptibility to ankylosing spondylitis: a meta-analysis.  

PubMed

The present meta-analysis of relevant case-control studies was conducted to investigate the possible relationships between genetic variations in the killer cell immunoglobulin-like receptor (KIR) gene clusters of the human KIR gene family and susceptibility to ankylosing spondylitis (AS). The following electronic databases were searched for relevant articles without language restrictions: the Web of Science, the Cochrane Library Database, PubMed, EMBASE, CINAHL, the Chinese Biomedical Database (CBM) and Chinese National Knowledge Infrastructure (CNKI) databases, covering all papers published until 2013. STATA statistical software was adopted in this meta-analysis as well. We also calculated the crude odds ratios (OR) and its 95 % confidence intervals (95 % CI). Seven case-control studies with 1,004 patients diagnosed with AS and 2,138 healthy cases were implicated in our meta-analysis, and 15 genes in the KIR gene family were also evaluated. The results of our meta-analysis show statistical significance between the genetic variations in the KIR2DL1, KIR2DS4, KIR2DS5 and KIR3DS1 genes and an increased susceptibility to AS (KIR2DL1: OR 7.82, 95 % CI 3.87-15.81, P< 0.001; KIR2DS4: OR 1.91, 95 % CI 1.16-3.13, P = 0.010; KIR2DS5: OR1.51, 95 % CI 1.14-2.01, P = 0.004; KIR3DS1: OR 1.58, 95 % CI 1.34-1.86, P< 0.001; respectively). However, we failed to found positive correlations between other genes and susceptibility to AS (all P >0.05). The current meta-analysis provides reliable evidence that genetic variations in the KIR gene family may contribute to susceptibility to AS, especially for the KIR2DL1, KIR2DS4, KIR2DS5 and KIR3DS1 genes. PMID:24880650

Zuo, Hai-Ning; Wang, Zhi-Long; Cui, Dao-Ran; Xin, Da-Jiang

2014-08-01

301

ROLE OF GENETIC SUSCEPTIBILITY TO LATENT ADENOVIRAL INFECTION AND DECREASED LUNG FUNCTION  

PubMed Central

Background Latent adenoviral infection may amplify cigarette smoke-induced lung inflammation and therefore play an important role in the development of chronic obstructive pulmonary disease (COPD). Adenoviruses can evade the human immune response via their 19-kDa protein (19K) which delays the expression of class I human leukocyte antigen (HLA) proteins. The 19K protein shows higher affinity to HLA-B7 and A2 compared with HLA-A1 and A3. The receptor for adenovirus (CXADR) and integrin ?5 (ITGB5) are host factors which might affect adenovirus infection. Therefore, we investigated the contribution of HLA, CXADR, and ITGB5 genetic variants to the presence of the E1A gene and to level of lung function. Methods Study subjects were assayed for HLA-B7, A1, A2 and A3 by PCR-based assays using allele-specific primers. Polymorphisms of the CXADR and ITGB5 genes were genotyped by PCR-based restriction fragment length polymorphism assays. Detection of adenoviral E1A gene was performed by a real-time PCR TaqMan assay. Results E1A positive individuals have a lower FEV1 compared with E1A negative individuals. However, there was no significant difference in E1A positivity rate between the high (HLA-B7 and A2) and low (HLA-A1 and A3) 19K affinity groups. There was also no significant difference in FEV1 level between each affinity group. There was no significant difference in E1A positivity rate or lung function among the CXADR and ITGB5 genotypes. Conclusions Genetic variants in HLA, CXADR and ITGB5 do not influence latent adenoviral infections and are not associated with COPD.

Kasuga, Ikuma; Hogg, James C.; Pare, Peter D.; Hayashi, Shizu; Sedgwick, Edward G.; Ruan, Jian; Wallace, Alison M.; He, Jian-Qing; Zhang, Xiaozhu; Sandford, Andrew J.

2009-01-01

302

Functional genetic polymorphisms in cytokines and metabolic genes as additional genetic markers for susceptibility to develop type 1 diabetes  

Microsoft Academic Search

Genetic association with type 1 diabetes (T1D) has been established for two chromosomal regions: HLA DQ\\/DR (IDDM1) and INS VNTR (IDDM2). To identify additional genetic markers, we tested polymorphisms in regulatory regions of several cytokine and important metabolic genes. These polymorphisms exhibit functional consequences for expression and function. Functional genetic polymorphisms of proinflammatory (T-helper-1: IL-2, IL-12 and IFN-?), anti-inflammatory (T-helper-2:

P Eerligh; B P C Koeleman; F Dudbridge; G Jan Bruining; B O Roep; M J Giphart; BPC Koeleman

2004-01-01

303

Genetic and Molecular Functional Characterization of Variants within TNFSF13B, a Positional Candidate Preeclampsia Susceptibility Gene on 13q  

Microsoft Academic Search

BackgroundPreeclampsia is a serious pregnancy complication, demonstrating a complex pattern of inheritance. The elucidation of genetic liability to preeclampsia remains a major challenge in obstetric medicine. We have adopted a positional cloning approach to identify maternal genetic components, with linkages previously demonstrated to chromosomes 2q, 5q and 13q in an Australian\\/New Zealand familial cohort. The current study aimed to identify

Mona H. Fenstad; Matthew P. Johnson; Linda T. Roten; Per A. Aas; Siri Forsmo; Kjetil Klepper; Christine E. East; Lawrence J. Abraham; John Blangero; Shaun P. Brennecke; Rigmor Austgulen; Eric K. Moses

2010-01-01

304

[Determination of the cytokine gene polymorphism and genetic susceptibility in tuberculosis patients].  

PubMed

Tuberculosis (TB) is a complicated disease in which biological, socioeconomical and environmental factors play role. Since only 10% of the individuals infected with Mycobacterium tuberculosis develop active disease, it has been suggested that host genetic factors may influence the risk for the development of TB. In this study, we aimed to investigate the presence and role of single nucleotide polymorphisms in the gene regions responsible for cytokine production, since these factors are considered to be associated with susceptibility or resistance to disease development. Single nucleotide polymorphisms were investigated by Amplification Refractory Mutational System (ARMS) Polymerase Chain Reaction (PCR) and PCR-Restriction Fragment Length Polymorphism (RFLP) methods. The presence of single nucleotide polymorphisms were analyzed in tumor necrosis factor alpha (TNF-?) gene promoter -308 G>A (rs1800629) region, interferon gamma (IFN-?) gene +874 T>A (rs61923114) region, interleukin (IL)-12B p40 gene 1188 A>C (rs3212227) region, IL-10 gene promoter -1082 G>A (rs1800896) region and IL-4 gene promoter -590 C>T (rs2243250) region. A total of 84 patients (71 male, 13 female; mean age: 32.57 ± 15.94 years) whose clinical samples yielded M.tuberculosis complex growth, and 110 healthy blood donors (93 male, 17 female; mean age: 29.40 ± 11.56 years) as control group were included in this study. Of the patients, 76 (90.5%) were diagnosed as pulmonary and 8 (9.5%) as extrapulmonary TB. While 79 (94.1%) patients were newly diagnosed as TB, 5 (5.9%) patients had a TB history (relapsed TB). It was detected that acid-fast bacilli (AFB) were positive in 58 (69%) patients. According to the single nucleotide polymorphism results, gene frequencies could not be compared for TNF-a gene promoter -308 G>A region since healthy controls were in Hardy-Weinberg equilibrium while the patients were not. There were no statistically significant differences in allele and genotype distribution between the patients and healthy controls in IFN-? gene +874 T>A region, IL-12B p40 gene 1188 A>C region, IL-10 gene promoter -1082 G>A region and IL-4 gene promoter -590 C>T region (p> 0.05). There were also no statistically significant differences between AFB positive (n= 58) and negative (n= 26) patients, and AFB positive (n= 56) and negative (n= 20) pulmonary TB patients (p> 0.05). In conclusion, no statistically significant differences were found associated with the susceptibility or resistance to TB with single nucleotide polymorphisms in the gene regions responsible for cytokine production in the study population. Only some of the single nucleotide polymorphisms of the gene regions responsible for cytokine release were investigated in our study. Therefore further detailed studies to investigate the polymorphisms in the genes that control the cytokine release and receptors specific for these cytokines, should be conducted. Although this study was performed in a relatively small sized population, these findings might provide a significant contribution to the epidemiologic data about the molecular immunology of TB in Turkey. PMID:23621725

Ulger, Mahmut; Emekda?, Gürol; Aslan, Gönül; Ta?, Dilaver; Ilvan, Ahmet; Tezcan, Seda; Cal?ko?lu, Mukadder; Erdal, M Emin; Kartalo?lu, Zafer

2013-04-01

305

Identification of shared genetic susceptibility locus for coronary artery disease, type 2 diabetes and obesity: a meta-analysis of genome-wide studies  

PubMed Central

Type 2 diabetes (2DM), obesity, and coronary artery disease (CAD) are frequently coexisted being as key components of metabolic syndrome. Whether there is shared genetic background underlying these diseases remained unclear. We performed a meta-analysis of 35 genome screens for 2DM, 36 for obesity or body mass index (BMI)-defined obesity, and 21 for CAD using genome search meta-analysis (GSMA), which combines linkage results to identify regions with only weak evidence and provide genetic interactions among different diseases. For each study, 120 genomic bins of approximately 30?cM were defined and ranked according to the best linkage evidence within each bin. For each disease, bin 6.2 achieved genomic significanct evidence, and bin 9.3, 10.5, 16.3 reached suggestive level for 2DM. Bin 11.2 and 16.3, and bin 10.5 and 9.3, reached suggestive evidence for obesity and CAD respectively. In pooled all three diseases, bin 9.3 and 6.5 reached genomic significant and suggestive evidence respectively, being relatively much weaker for 2DM/CAD or 2DM/obesity or CAD/obesity. Further, genomewide significant evidence was observed of bin 16.3 and 4.5 for 2DM/obesity, which is decreased when CAD was added. These findings indicated that bin 9.3 and 6.5 are most likely to be shared by 2DM, obesity and CAD. And bin 16.3 and 4.5 are potentially common regions to 2DM and obesity only. The observed shared susceptibility regions imply a partly overlapping genetic aspects of disease development. Fine scanning of these regions will definitely identify more susceptibility genes and causal variants.

2012-01-01

306

Novel Susceptibility Loci for Second Primary Tumors/Recurrence in Head and Neck Cancer Patients: Large Scale Evaluation of Genetic Variants  

PubMed Central

Background This study was aimed to identify novel susceptibility variants for second primary tumor (SPT) or recurrence in curatively treated early stage head and neck squamous cell carcinoma (HNSCC) patients. Methods We constructed a custom chip containing a comprehensive panel of 9645 chromosomal and mitochondrial single nucleotide polymorphisms (SNPs) representing 998 cancer-related genes selected by a systematic prioritization schema. Using this chip, we genotyped 150 early-stage HNSCC patients with and 300 matched patients without SPT/recurrence from a prospectively conducted randomized trial and assessed the association of these SNPs with risk of SPT/recurrence. Results Individually, six chromosomal SNPs and seven mitochondrial SNPs (mtSNPs) were significantly associated with risk of SPT/recurrence after adjustment for multiple comparisons. A strong gene-dosage effect was observed these SNPs were combined, as evidenced by a progressively increasing SPT/recurrence risk as the number of unfavorable genotypes increased (P for trend < 1.00×10?20). Several polygenic analyses suggest an important role of interconnected functional network and gene-gene interaction in modulating SPT/recurrence. Furthermore, incorporation of these genetic markers into a multivariate model improved significantly the discriminatory ability over the models containing only clinical and epidemiologic variables. Conclusions This is the first large scale systematic evaluation of germline genetic variants for their roles in HNSCC SPT/recurrence. The study identified several promising susceptibility loci and demonstrated the cumulative effect of multiple risk loci in HNSCC SPT/recurrence. Furthermore, this study underscores the importance of incorporating germline genetic variation data with clinical and risk factor data in constructing prediction models for clinical outcomes.

Wu, Xifeng; Spitz, Margaret R.; Lee, J. Jack; Lippman, Scott M.; Ye, Yuanqing; Yang, Hushan; Khuri, Fadlo R.; Kim, Edward; Gu, Jian; Lotan, Reuben; Hong, Waun K.

2010-01-01

307

Genetic variant in IL33 is associated with susceptibility to rheumatoid arthritis  

PubMed Central

Introduction Interleukin (IL)-33 is a proinflammatory cytokine contributing to the pathogenesis of rheumatoid arthritis (RA). The gene encoding IL-33 may serve as a genetic factor and be associated with the risk of RA. To investigate the potential association between IL33 and RA, we performed a case–control study based on Chinese Han population. Methods A three-stage case–control study was performed. Two tag single-nucleotide polymorphisms (SNPs) (rs7044343 and rs10975514), mapping to the IL33 gene, were first genotyped in the discovery population. We further genotyped rs7044343 and rs10975514 in the validation and replication population. The associations between the two tag SNPs and phenotypic subgroups of RA and levels of serum IL-33 were assessed with a logistic regression model. Results In the discovery population, the CC genotype of rs7044343 was associated with RA patients (odds ratio (OR)?=?0.777, 95% confidence interval (CI), 0.611 to 0.988; P?=?0.040). After anti-citrullinated peptide antibody (ACPA) stratification, the CC genotype of rs7044343 was also shown to be a protective genotype in RA without ACPA (OR?=?0.610; 95% CI, 0.379 to 0.982; P?=?0.042). In the validation population and replication population, the association between rs7044343 and RA, especially ACPA-negative RA, was still significant. A meta-analysis of discovery, validation, and replication panels confirmed the association between CC genotype of rs7044343 and RA (Pcombined?=?0.0004; ORcombined?=?0.77; 95% CI, 0.67 to 0.89). No evidence was found for heterogeneity between three sample sets (Phet?=?0.99; I2?=?0%). Similar results were also obtained in ACPA-negative RA (Pcombined?=?0.0002; ORcombined?=?0.57; 95% CI, 0.43 to 0.77). No association was detected between rs10975514 polymorphism and RA susceptibility in the discovery and validation population. The serum levels of IL-33 were significantly lower in the patients with the rs7044343 CC genotype. Conclusion The CC genotype of rs7044343 in IL33 is associated with RA patients and downregulates IL-33 expression in RA.

2014-01-01

308

Genetic and Functional Profiling of Crohn's Disease: Autophagy Mechanism and Susceptibility to Infectious Diseases  

PubMed Central

Crohn's disease is a complex disease in which genome, microbiome, and environment interact to produce the immunological background of the disease. Disease in childhood is more extensive and characterized by a rapid progression, leading to severe repercussions in the course of the disorder. Several genetic variations have been associated with an increased risk of developing the disease and most of these are also implicated in other autoimmune disorders. The gut has many tiers of defense against incursion by luminal microbes, including the epithelial barrier and the innate and adaptive immune responses. Moreover, recent evidence shows that bacterial and viral infections, as well as inflammasome genes and genes involved in the autophagy process, are implicated in Crohn's disease pathogenesis. The aim of this review is to establish how much the diagnostic system can improve, thus increasing the success of Crohn's disease diagnosis. The major expectation for the near future is to be able to anticipate the possible consequences of the disease already in childhood, thus preventing associated complications, and to choose the best treatment for each patient.

Bianco, Anna Monica; Girardelli, Martina; Tommasini, Alberto; Martelossi, Stefano

2013-01-01

309

Differences in corneal phenotypes between destrin mutants are due to allelic difference and modified by genetic background  

PubMed Central

Purpose Mutations in destrin (Dstn) cause corneal abnormalities in mice. A null mutation, Dstncorn1, results in corneal epithelial hyperproliferation, inflammation, and neovascularization in the A.BY background (A.BY Dstncorn1). Homozygosity for a point mutation, Dstncorn1–2J, results in mild thickening of the corneal epithelium but no corneal neovascularization in a C57BL/6 (B6) background (B6 Dstncorn1–2J). The goal of this study was to determine whether phenotypic differences are due to allelic differences between Dstncorn1 and Dstncorn1–2J, or are the result of genetic background effects. Methods We generated two congenic (Cg) mouse lines, B6.Cg-Dstncorn1 and A.BY.Cg-Dstncorn1–2J, to compare to the original A.BY Dstncorn1 and B6 Dstncorn1–2J lines. We performed immunohistochemistry to assay F-actin accumulation, neovascularization, proliferation, and inflammation. By western blot analysis we tested the expression of serum response factor (SRF), a known regulator of the Dstncorn1 phenotype. Results The Dstncorn1 mutation leads to neovascularization, hyperproliferation, and inflammation in the cornea of A.BY Dstncorn1 as well as B6.Cg-Dstncorn1 mice. We did not observe significant corneal neovascularization or hyperproliferation in either A.BY.Cg-Dstncorn1–2J or B6 Dstncorn1–2J mice. Actin accumulation, neovascularization, epithelial proliferation and inflammation in B6.Cg-Dstncorn1 cornea are significantly reduced when compared to A.BY Dstncorn1cornea. SRF changes are consistent in Dstncorn1 mutants, regardless of genetic background. Conclusions Differences in the abnormal phenotypes of Dstn mutants result from allelic differences between Dstncorn1 and Dstncorn1–2J . Moreover, phenotypes of Dstncorn1 mice are modified by genetic background, suggesting the existence of genetic modifiers. Protein analysis suggests that a genetic modifier affects phenotypic severity functionally downstream from or in a pathway independent from SRF. These data demonstrate that natural genetic variation affects phenotypic severity in Dstncorn1 mice.

Kawakami-Schulz, Sharolyn V.; Sattler, Shannon G.; Ikeda, Akihiro; Ikeda, Sakae

2012-01-01

310

A novel hairless mouse model on an atopic dermatitis-prone genetic background generated by receptor-mediated transgenesis  

Microsoft Academic Search

Current mouse models for atopic dermatitis (AD) have a serious drawback, being the existence of dense hair on the body. Thus,\\u000a a hairless animal model on an AD-prone genetic background will be a powerful tool to investigate the basis of and therapy\\u000a for this complex disease. We applied the Toxin Receptor-mediated Cell Knockout (TRECK) method to generate a hairless transgenic

Toyoyuki Takada; Hiroshi Shitara; Kunie Matsuoka; Erika Kojima; Rie Ishii; Yoshiaki Kikkawa; Choji Taya; Hajime Karasuyama; Kenji Kohno; Hiromichi Yonekawa

2008-01-01

311

Expression of Drosophila mushroom body mutations in alternative genetic backgrounds: a case study of the mushroom body miniature gene (mbm).  

PubMed Central

Mutations in 12 genes regulating Drosophila melanogaster mushroom body (MB) development were each studied in two genetic backgrounds. In all cases, brain structure was qualitatively or quantitatively different after replacement of the "original" genetic background with that of the Canton Special wild-type strain. The mushroom body miniature gene (mbm) was investigated in detail. mbm supports the maintenance of MB Kenyon cell fibers in third instar larvae and their regrowth during metamorphosis. Adult mbm1 mutant females are lacking many or most Kenyon cell fibers and are impaired in MB-mediated associative odor learning. We show here that structural defects in mbm1 are apparent only in combination with an X-linked, dosage-dependent modifier (or modifiers). In the Canton Special genetic background, the mbm1 anatomical phenotype is suppressed, and MBs develop to a normal size. However, the olfactory learning phenotype is not fully restored, suggesting that submicroscopic defects persist in the MBs. Mutant mbm1 flies with full-sized MBs have normal retention but show a specific acquisition deficit that cannot be attributed to reductions in odor avoidance, shock reactivity, or locomotor behavior. We propose that polymorphic gene interactions (in addition to ontogenetic factors) determine MB size and, concomitantly, the ability to recognize and learn odors. Images Fig. 1 Fig. 2 Fig. 3

de Belle, J S; Heisenberg, M

1996-01-01

312

Refinement of the background genetic map of Xq26-q27 and gene localisation for Boerjeson-Forssman-Lehmann syndrome  

SciTech Connect

A detailed map of genetic markers was constructed around the gene for the X-linked mental retardation syndrome of Borjeson-Forssman-Lehmann (BFLS). A multipoint linkage map of framework markers across Xq26-27, based on CEPH families, was integrated with the physical map, based on a YAC contig, to confirm marker order. The remaining genetic markers, which could not be ordered by linkage, were added to create the comprehensive genetic background map, in the order determined by physical mapping, to determine genetic distances between adjacent markers. This background genetic map is applicable to the refinement of the regional localization for any disease gene mapping to this region. The BFLS gene was localized using this background map in an extended version of the family described by Turner et al. The regional localization for BFLS extends between recombination events at DXS425 and DXS105, an interval of 24.6 cM on the background genetic map. The phenotypic findings commonly seen in the feet of affected males and obligate carrier females may represent a useful clinical indicator of carrier status in potential female carriers in the family. Recombination between DXS425 and DXS105 in a female with such characteristic feet suggests that the distal limit of the regional localization for the BFLS gene might reasonably be reduced to DXS294 for the purpose of selecting candidate genes, reducing the interval for the BFLS gene to 15.5 cM. Positional candidate genes from the interval between DXS425 and DXS105 include the SOX3 gene, mapped between DXS51(52A) and DXS98(4D-8). SOX3 may have a role in regulating the development of the nervous system. The HMG-box region of this single exon gene was examined by PCR for a deletion and then sequenced. No deviation from normal was observed, excluding mutations in the conserved HMG-box region as the cause of BFLS in this family. 27 refs., 1 fig., 2 tabs.

Gedeon, A.K.; Kozman, H.M.; Mulley, J.C. [Univ. of Adelaide (Australia)] [and others] [Univ. of Adelaide (Australia); and others

1996-07-12

313

Genomic selection for recovery of original genetic background from hybrids of endangered and common breeds  

PubMed Central

Critically endangered breeds and populations are often crossed with more common breeds or subspecies. This results in genetic admixture that can be undesirable when it challenges the genetic integrity of wild and domestic populations, causing a loss in special characteristics or unique genetic material and ultimately extinction. Here, we present two genomic selection strategies, using genome-wide DNA markers, to recover the genomic content of the original endangered population from admixtures. Each strategy relies on the estimation of the proportion of nonintrogressed genome in individuals based on a different method: either genomic prediction or identification of breed-specific haplotypes. Then, breeding programs that remove introgressed genomic information can be designed. To test these strategies, we used empirical 50K SNP array data from two pure sheep breeds, Merino (used as target breed), Poll Dorset and an existing admixed population of both breeds. Sheep populations with varying degrees of introgression and admixture were simulated starting from these real genotypes. Both strategies were capable of identifying segment origin, and both removed up to the 100% of the Poll Dorset segments. While the selection process led to substantial inbreeding, we controlled it by imposing a minimum number of individuals contributing to the next generation.

Amador, Carmen; Hayes, Ben J; Daetwyler, Hans D

2014-01-01

314

Sardinians Genetic Background Explained by Runs of Homozygosity and Genomic Regions under Positive Selection  

PubMed Central

The peculiar position of Sardinia in the Mediterranean sea has rendered its population an interesting biogeographical isolate. The aim of this study was to investigate the genetic population structure, as well as to estimate Runs of Homozygosity and regions under positive selection, using about 1.2 million single nucleotide polymorphisms genotyped in 1077 Sardinian individuals. Using four different methods - fixation index, inflation factor, principal component analysis and ancestry estimation - we were able to highlight, as expected for a genetic isolate, the high internal homogeneity of the island. Sardinians showed a higher percentage of genome covered by RoHs>0.5 Mb (FRoH%0.5) when compared to peninsular Italians, with the only exception of the area surrounding Alghero. We furthermore identified 9 genomic regions showing signs of positive selection and, we re-captured many previously inferred signals. Other regions harbor novel candidate genes for positive selection, like TMEM252, or regions containing long non coding RNA. With the present study we confirmed the high genetic homogeneity of Sardinia that may be explained by the shared ancestry combined with the action of evolutionary forces.

Di Gaetano, Cornelia; Fiorito, Giovanni; Ortu, Maria Francesca; Rosa, Fabio; Guarrera, Simonetta; Pardini, Barbara; Cusi, Daniele; Frau, Francesca; Barlassina, Cristina; Troffa, Chiara; Argiolas, Giuseppe; Zaninello, Roberta; Fresu, Giovanni; Glorioso, Nicola; Piazza, Alberto; Matullo, Giuseppe

2014-01-01

315

Genome-Wide Association Study to Identify the Genetic Determinants of Otitis Media Susceptibility in Childhood  

PubMed Central

Background Otitis media (OM) is a common childhood disease characterised by middle ear inflammation and effusion. Susceptibility to recurrent acute OM (rAOM; ?3 episodes of AOM in 6 months) and chronic OM with effusion (COME; MEE ?3 months) is 40–70% heritable. Few underlying genes have been identified to date, and no genome-wide association study (GWAS) of OM has been reported. Methods and Findings Data for 2,524,817 single nucleotide polymorphisms (SNPs; 535,544 quality-controlled SNPs genotyped by Illumina 660W-Quad; 1,989,273 by imputation) were analysed for association with OM in 416 cases and 1,075 controls from the Western Australian Pregnancy Cohort (Raine) Study. Logistic regression analyses under an additive model undertaken in GenABEL/ProbABEL adjusting for population substructure using principal components identified SNPs at CAPN14 (rs6755194: OR?=?1.90; 95%CI 1.47–2.45; Padj-PCA?=?8.3×10?7) on chromosome 2p23.1 as the top hit, with independent effects (rs1862981: OR?=?1.60; 95%CI 1.29–1.99; Padj-PCA?=?2.2×10?5) observed at the adjacent GALNT14 gene. In a gene-based analysis in VEGAS, BPIFA3 (PGene?=?2×10?5) and BPIFA1 (PGene?=?1.07×10?4) in the BPIFA gene cluster on chromosome 20q11.21 were the top hits. In all, 32 genomic regions show evidence of association (Padj-PCA<10?5) in this GWAS, with pathway analysis showing a connection between top candidates and the TGF? pathway. However, top and tag-SNP analysis for seven selected candidate genes in this pathway did not replicate in 645 families (793 affected individuals) from the Western Australian Family Study of Otitis Media (WAFSOM). Lack of replication may be explained by sample size, difference in OM disease severity between primary and replication cohorts or due to type I error in the primary GWAS. Conclusions This first discovery GWAS for an OM phenotype has identified CAPN14 and GALNT14 on chromosome 2p23.1 and the BPIFA gene cluster on chromosome 20q11.21 as novel candidate genes which warrant further analysis in cohorts matched more precisely for clinical phenotypes.

Rye, Marie S.; Warrington, Nicole M.; Scaman, Elizabeth S. H.; Vijayasekaran, Shyan; Coates, Harvey L.; Anderson, Denise; Pennell, Craig E.; Blackwell, Jenefer M.; Jamieson, Sarra E.

2012-01-01

316

Genetic Polymorphisms in CYP2E1: Association with Schizophrenia Susceptibility and Risperidone Response in the Chinese Han Population  

PubMed Central

Background CYP2E1 is a member of the cytochrome P450 superfamily, which is involved in the metabolism and activation of both endobiotics and xenobiotics. The genetic polymorphisms of CYP2E1 gene (Chromosome 10q26.3, Accession Number NC_000010.10) are reported to be related to the development of several mental diseases and to be involved in the clinical efficacy of some psychiatric medications. We investigated the possible association of CYP2E1 polymorphisms with susceptibility to schizophrenia in the Chinese Han Population as well as the relationship with response to risperidone in schizophrenia patients. Methods In a case-control study, we identified 11 polymorphisms in the 5' flanking region of CYP2E1 in 228 schizophrenia patients and 384 healthy controls of Chinese Han origin. From among the cases, we chose 130 patients who had undergone 8 weeks of risperidone monotherapy to examine the relationship between their response to risperidone and CYP2E1 polymorphisms. Clinical efficacy was assessed using the Brief Psychiatric Rating Scale (BPRS). Results Statistically significant differences in allele or genotype frequencies were found between cases and controls at rs8192766 (genotype p?=?0.0048, permutation p?=?0.0483) and rs2070673 (allele: p?=?0.0018, permutation p?=?0.0199, OR?=?1.4528 95%CI?=?1.1487–1.8374; genotype: p?=?0.0020, permutation p?=?0.0225). In addition, a GTCAC haplotype containing 5 SNPs (rs3813867, rs2031920, rs2031921, rs3813870 and rs2031922) was observed to be significantly associated with schizophrenia (p?=?7.47E-12, permutation p<0.0001). However, no association was found between CYP2E1 polymorphisms/haplotypes and risperidone response. Conclusions Our results suggest that CYP2E1 may be a potential risk gene for schizophrenia in the Chinese Han population. However, polymorphisms of the CYP2E1 gene may not contribute significantly to individual differences in the therapeutic efficacy of risperidone. Further studies in larger groups are warranted to confirm our results.

Wei, Zhiyun; Shen, Lu; Xiong, Yuyu; Wu, Xi; Niu, Jiamin; Han, Xia; Tian, Zhengan; Yang, Lun; Feng, Guoyin; He, Lin; Qin, Shengying

2012-01-01

317

Genetic variation in the TNF receptor-associated factor 6 gene is associated with susceptibility to sepsis-induced acute lung injury  

PubMed Central

Background Recent studies showed that overwhelming inflammatory response mediated by the toll-like receptor (TLR)-related pathway was important in the development of acute lung injury (ALI). The aim of this study was to determine whether common genetic variation in four genes of the TLR signaling pathway were associated with sepsis-induced ALI susceptibility and risk of death in Chinese Han population. Methods Fourteen tag single nucleotide polymorphisms (tagSNPs) in MyD88, IRAK1, IRAK4 and TRAF6 were genotyped in samples of sepsis-induced ALI (n?=?272) and sepsis alone patients (n?=?276), and tested for association in this case-control collection. Then, we investigated correlation between the associated SNP and the mRNA expression level of the corresponding gene. And we also investigated correlation between the associated SNP and tumor necrosis factor alpha (TNF-?) as well as interleukin-6 (IL-6) concentrations in peripheral blood mononuclear cells (PBMCs) exposed to lipopolysaccharides (LPS) ex vivo. The mRNA expression level was determined using real-time quantitative Polymerase Chain Reaction (PCR) assays, and concentrations of TNF-? and IL-6 were measured by enzyme-linked immunosorbent assay (ELISA). Results The association analysis revealed that rs4755453, an intronic SNP of TRAF6, was significantly associated with susceptibility to sepsis-induced ALI. The C allele frequency of rs4755453 in the sepsis alone group was significantly higher than that in the sepsis-induced ALI group (P?=?0.00026, odds ratio (OR) = 0.52, 95% confidence interval (CI) 0.37–0.74). These associations remained significant after adjustment for covariates in multiple logistic regression analysis and for multiple comparisons. TRAF6 mRNA expression levels in PBMCs from homozygotes of the rs4755453G allele were significantly higher than that in heterozygotes and homozygotes of the rs4755453C allele at baseline (P?=?0.012 and P?=?0.003, respectively) as well as after LPS stimulation (P?=?0.009 and P?=?0.005). Moreover, the concentrations of TNF-? and IL-6 in cell culture supernatants were also significantly higher in the subjects with rs4755453GG genotype than in subjects with CG and CC genotype. None of the 14 tagSNPs showed associations with risk of death and severity among ALI cases. Conclusions Our findings indicated that common genetic variants in TRAF6 were significantly associated with susceptibility to sepsis-induced ALI in Chinese Han population. This was the first genetic evidence supporting a role for TRAF6 in ALI.

2012-01-01

318

Genetic variation in SIRT1 affects susceptibility of lung squamous cell carcinomas in former uranium miners from the Colorado plateau.  

PubMed

Epidemiological studies of underground miners suggested that occupational exposure to radon causes lung cancer with squamous cell carcinoma (SCC) as the predominant histological type. However, the genetic determinants for susceptibility of radon-induced SCC in miners are unclear. Double-strand breaks induced by radioactive radon daughters are repaired primarily by non-homologous end joining (NHEJ) that is accompanied by the dynamic changes in surrounding chromatin, including nucleosome repositioning and histone modifications. Thus, a molecular epidemiological study was conducted to assess whether genetic variation in 16 genes involved in NHEJ and related histone modification affected susceptibility for SCC in radon-exposed former miners (267 SCC cases and 383 controls) from the Colorado plateau. A global association between genetic variation in the haplotype block where SIRT1 resides and the risk for SCC in miners (P = 0.003) was identified. Haplotype alleles tagged by the A allele of SIRT1 rs7097008 were associated with increased risk for SCC (odds ratio = 1.69, P = 8.2 × 10(-5)) and greater survival in SCC cases (hazard ratio = 0.79, P = 0.03) in miners. Functional validation of rs7097008 demonstrated that the A allele was associated with reduced gene expression in bronchial epithelial cells and compromised DNA repair capacity in peripheral lymphocytes. Together, these findings substantiate genetic variation in SIRT1 as a risk modifier for developing SCC in miners and suggest that SIRT1 may also play a tumor suppressor role in radon-induced cancer in miners. PMID:23354305

Leng, Shuguang; Picchi, Maria A; Liu, Yushi; Thomas, Cynthia L; Willis, Derall G; Bernauer, Amanda M; Carr, Teara G; Mabel, Padilla T; Han, Younghun; Amos, Christopher I; Lin, Yong; Stidley, Christine A; Gilliland, Frank D; Jacobson, Marty R; Belinsky, Steven A

2013-05-01

319

The Influence of Genetic Background on Conventional Outflow Facility in Mice  

PubMed Central

Purpose. Intraocular pressure (IOP) varies between genetically distinct strains of mice. The purpose was to test the hypothesis that strain-dependent differences in IOP are attributable to differences in conventional outflow facility (C). Methods. The IOP was measured by rebound tonometry in conscious or anesthetized BALB/cJ, C57BL/6J, and CBA/J mice (N = 6–10 per strain). Conventional outflow facility was measured by ex vivo perfusion of enucleated eyes (N = 9–10 per strain). Results. Conscious IOP varied between strains, being highest in CBA/J (14.5 ± 0.9 mm Hg, mean ± SD), intermediate in C57BL/6J (12.3 ± 1.0 mm Hg), and lowest in BALB/cJ (10.6 ± 1.8 mm Hg) mice. Anesthesia reduced IOP and eliminated any detectable differences between strains. Conventional outflow facility also varied between strains, but, in contrast to IOP, C was lowest in CBA/J (0.0113 ± 0.0031 ?L/min/mm Hg) and highest in BALB/cJ (0.0164 ± 0.0059 ?L/min/mm Hg). Like IOP, C was intermediate in C57BL/6J (0.0147 ± 0.0029 ?L/min/mm Hg). There was a strong correlation between conscious IOP and outflow resistance (1/C) from individual eyes across all three strains, revealing that 70% of the variation in IOP was attributable to variation in outflow resistance. Conclusions. Differences in IOP among three genetically distinct murine strains are attributable largely to differences in conventional outflow facility. These results motivate further studies using mice to identify the morphologic and genetic factors that underlie IOP regulation within the conventional outflow pathway.

Boussommier-Calleja, Alexandra; Overby, Darryl R.

2013-01-01

320

Eimeria Species and Genetic Background Influence the Serum Protein Profile of Broilers with Coccidiosis  

Microsoft Academic Search

BackgroundCoccidiosis is an intestinal disease caused by protozoal parasites of the genus Eimeria. Despite the advent of anti-coccidial drugs and vaccines, the disease continues to result in substantial annual economic losses to the poultry industry. There is still much unknown about the host response to infection and to date there are no reports of protein profiles in the blood of

Elizabeth R. Gilbert; Chasity M. Cox; Patricia M. Williams; Audrey P. McElroy; Rami A. Dalloul; W. Keith Ray; Adriana Barri; Derek A. Emmerson; Eric A. Wong; Kenneth E. Webb; Amit Singh

2011-01-01

321

Population Genetics of GYPB and Association Study between GYPB*S/s Polymorphism and Susceptibility to P. falciparum Infection in the Brazilian Amazon  

PubMed Central

Background Merozoites of Plasmodium falciparum invade through several pathways using different RBC receptors. Field isolates appear to use a greater variability of these receptors than laboratory isolates. Brazilian field isolates were shown to mostly utilize glycophorin A-independent invasion pathways via glycophorin B (GPB) and/or other receptors. The Brazilian population exhibits extensive polymorphism in blood group antigens, however, no studies have been done to relate the prevalence of the antigens that function as receptors for P. falciparum and the ability of the parasite to invade. Our study aimed to establish whether variation in the GYPB*S/s alleles influences susceptibility to infection with P. falciparum in the admixed population of Brazil. Methods Two groups of Brazilian Amazonians from Porto Velho were studied: P. falciparum infected individuals (cases); and uninfected individuals who were born and/or have lived in the same endemic region for over ten years, were exposed to infection but have not had malaria over the study period (controls). The GPB Ss phenotype and GYPB*S/s alleles were determined by standard methods. Sixty two Ancestry Informative Markers were genotyped on each individual to estimate admixture and control its potential effect on the association between frequency of GYPB*S and malaria infection. Results GYPB*S is associated with host susceptibility to infection with P. falciparum; GYPB*S/GYPB*S and GYPB*S/GYPB*s were significantly more prevalent in the in the P. falciparum infected individuals than in the controls (69.87% vs. 49.75%; P<0.02). Moreover, population genetics tests applied on the GYPB exon sequencing data suggest that natural selection shaped the observed pattern of nucleotide diversity. Conclusion Epidemiological and evolutionary approaches suggest an important role for the GPB receptor in RBC invasion by P. falciparum in Brazilian Amazons. Moreover, an increased susceptibility to infection by this parasite is associated with the GPB S+ variant in this population.

Amaral, Daphne R. T.; Costa, Daiane C.; Furlani, Natalia G.; Zuccherato, Luciana W.; Machado, Moara; Reid, Marion E.; Zalis, Mariano G.; Rossit, Andrea R.; Santos, Sidney E. B.; Machado, Ricardo L.; Lustigman, Sara

2011-01-01

322

Epistatic interactions between Tgfb1 and genetic loci, Tgfbm2 and Tgfbm3, determine susceptibility to an asthmatic stimulus  

PubMed Central

TGF? activation and signaling have been extensively studied in experimental models of allergen-induced asthma as potential therapeutic targets during chronic or acute phases of the disease. Outcomes of experimental manipulation of TGF? activity have been variable, in part due to use of different model systems. Using an ovalbumin (OVA)-induced mouse model of asthma, we here show that innate variation within TGF?1 genetic modifier loci, Tgfbm2 and Tgfbm3, alters disease susceptibility. Specifically, Tgfbm2129 and Tgfbm3C57 synergize to reverse accentuated airway hyperresponsiveness (AHR) caused by low TGF?1 levels in Tgfb1+/? mice of the NIH/OlaHsd strain. Moreover, epistatic interaction between Tgfbm2129 and Tgfbm3C57 uncouples the inflammatory response to ovalbumin from those of airway remodeling and airway hyperresponsiveness, illustrating independent genetic control of these responses. We conclude that differential inheritance of genetic variants of Tgfbm genes alters biological responses to reduced TGF?1 signaling in an experimental asthma model. TGF? antagonists for treatment of lung diseases might therefore give diverse outcomes, dependent on genetic variation.

Freimuth, Julia; Clermont, Frederic F.; Huang, Xiaozhu; DeSapio, Angela; Tokuyasu, Taku A.; Sheppard, Dean; Akhurst, Rosemary J.

2012-01-01

323

[Genetic variation of NADPH/NADH oxidase and susceptibility to diffuse panbronchiolitis (DPB) and chronic obstructive pulmonary disease (COPD)].  

PubMed

Diffuse panbronchiolitis (DPB) and chronic obstructive pulmonary disease (COPD) are both characterized by chronic airflow obstruction of unknown etiology. It is hypothesized that neutrophils play the major role in the pathogenesis of these diseases. Recent studies have suggested that genetic factors may be related to individual susceptibility to these diseases. We have investigated the association between the C 242 T polymorphism of p 22 phox, a critical subunit of superoxide-generating NADH/NADPH oxidase, and susceptibility to DPB and COPD. Blood samples obtained from both patients with DPB (n = 82), COPD (n = 53), and control subjects (n = 82) were used for this genotyping assay; and the polymerase chain reaction (PCR) and restriction fragment length polymorphism (RFLP) were performed to genotype the gene. The frequency of the C allele was 0.91, 0.92, 0.92 in the DPB, COPD, and control groups, respectively. There were no differences in the distribution of the genotype of p 22 phox among these groups, either. We concluded that there is no association between the C 242 T polymorphism of p 22 phox, and susceptibility to DPB and COPD. PMID:11510094

Ishii, T; Keicho, N; Teramoto, S; Azuma, A; Kudoh, S; Fukuchi, Y; Ouchi, Y; Matsuse, T

2001-05-01

324

The CRHR1 gene contributes to genetic susceptibility of aggressive behavior towards others in Chinese southwest Han population.  

PubMed

Accumulating evidence suggests that the hypothalamic-pituitary-adrenal (HPA) axis might play a major role in genetic susceptibility of aggressive behavior. The aim of the present study is to investigate the association between corticotrophin-releasing hormone receptor 1 (CRHR1) gene and aggressive behavior in Chinese southwest Han population. Participants consist of 282 healthy controls and 177 violent criminals (including robbery and intentional injury, which represent for aggressive behavior towards property and aggressive behavior towards others). Three tag single nucleotide polymorphisms (SNPs) of CRHR1 gene including rs4458044, rs242924, and rs1768996 were genotyped using improved multiplex ligase detection reaction (iMLDR) methods. Single-locus analysis revealed that none of the studied SNPs was significantly associated with the risk of aggressive behavior; however, haplotype analysis showed that a haplotype GGA significantly increased the susceptibility of aggressive behavior towards others with an odds ratios equal to 3.32 (p = 0.003). The present results, for the first time, indicate that the CRHR1 gene polymorphism is significantly associated with aggressive behavior in Chinese southwest Han population. Subjects with GGA haplotype have an increased susceptibility to aggressive behavior towards others. PMID:24243082

Chen, Bifeng; Gu, Tao; Ma, Bo; Zheng, Guoqing; Ke, Bingxiong; Zhang, Xiufeng; Zhang, Lirui; Wang, Yuanyuan; Hu, Liping; Chen, Yang; Qiu, Jianbo; Nie, Shengjie

2014-04-01

325

Background Strain and the Differential Susceptibility of Podocyte-Specific Deletion of Myh9 on Murine Models of Experimental Glomerulosclerosis and HIV Nephropathy  

PubMed Central

We previously reported that podocyte-specific deletion of Myh9 (conventional myosin heavy chain 2A) in C57BL/6 mice does not cause spontaneous kidney disease but instead results in a predisposition to glomerulosclerosis in response to a second model of glomerular injury. In contrast, other investigators reported that podocyte-specific deletion of Myh9 (Pod?Myh9) resulted in spontaneous glomerulosclerosis in mice on a mixed background, suggesting that the glomerulosclerosis is dependent on background strain. In order to elucidate the cause of this strain dependent effect Podocin::Cre and Myh9flox alleles were backcrossed to mouse strain FVB/N, which is highly susceptible to glomerulosclerosis, with the aim of intercrossing susceptible FVB/N and resistant C57BL/6 mice in subsequent congenic analyses. However, after backcrossing mice to FVB/N and aging mice to 28 weeks, we found no evidence of glomerular disease in Pod?Myh9 mice vs control littermates (urine MAC ratio all p>0.05). We also tested C57BL/6 Pod?Myh9 mice for a predisposition to injury from models other than Adriamycin including HIV nephropathy (HIVAN), puromycin nephropathy, and sheep nephrotoxic serum. In the Tg26 model of HIVAN, we found that podocyte-specific deletion of Myh9 resulted in a modest hypersensitivity in adults compared to Tg26+ control littermates (urine MAC ratio, p<0.05 or less). In contrast, we found that Pod?Myh9 mice were not predisposed to injury in response to other injury models including puromycin nephropathy and sheep nephrotoxic serum. While the mechanism of injury in these models is not fully understood, we conclude that Pod?Myh9 results in a variable susceptibility to glomerulosclerosis in response to different models of glomerular injury. In addition, based on the lack of a spontaneous phenotype of glomerulosclerosis in both C57BL/6 and FVB/N mice, we propose that Myh9 is not absolutely required in adult podocytes.

Johnstone, Duncan B.; Ikizler, Omer; Zhang, Jidong; Holzman, Lawrence B.

2013-01-01

326

Background strain and the differential susceptibility of podocyte-specific deletion of Myh9 on murine models of experimental glomerulosclerosis and HIV nephropathy.  

PubMed

We previously reported that podocyte-specific deletion of Myh9 (conventional myosin heavy chain 2A) in C57BL/6 mice does not cause spontaneous kidney disease but instead results in a predisposition to glomerulosclerosis in response to a second model of glomerular injury. In contrast, other investigators reported that podocyte-specific deletion of Myh9 (Pod?Myh9) resulted in spontaneous glomerulosclerosis in mice on a mixed background, suggesting that the glomerulosclerosis is dependent on background strain. In order to elucidate the cause of this strain dependent effect Podocin::Cre and Myh9(flox) alleles were backcrossed to mouse strain FVB/N, which is highly susceptible to glomerulosclerosis, with the aim of intercrossing susceptible FVB/N and resistant C57BL/6 mice in subsequent congenic analyses. However, after backcrossing mice to FVB/N and aging mice to 28 weeks, we found no evidence of glomerular disease in Pod?Myh9 mice vs control littermates (urine MAC ratio all p>0.05). We also tested C57BL/6 Pod?Myh9 mice for a predisposition to injury from models other than Adriamycin including HIV nephropathy (HIVAN), puromycin nephropathy, and sheep nephrotoxic serum. In the Tg26 model of HIVAN, we found that podocyte-specific deletion of Myh9 resulted in a modest hypersensitivity in adults compared to Tg26+ control littermates (urine MAC ratio, p<0.05 or less). In contrast, we found that Pod?Myh9 mice were not predisposed to injury in response to other injury models including puromycin nephropathy and sheep nephrotoxic serum. While the mechanism of injury in these models is not fully understood, we conclude that Pod?Myh9 results in a variable susceptibility to glomerulosclerosis in response to different models of glomerular injury. In addition, based on the lack of a spontaneous phenotype of glomerulosclerosis in both C57BL/6 and FVB/N mice, we propose that Myh9 is not absolutely required in adult podocytes. PMID:23874454

Johnstone, Duncan B; Ikizler, Omer; Zhang, Jidong; Holzman, Lawrence B

2013-01-01

327

Establishment and Characterization of MRT Cell Lines from Genetically Engineered Mouse Models and the Influence of Genetic Background on Their Development  

PubMed Central

Malignant rhabdoid tumors (MRTs) are rare, aggressive cancers occuring in young children primarily through inactivation of the SNF5(INI1, SMARCB1) tumor suppressor gene. We and others have demonstrated that mice heterozygous for a Snf5 null allele develop MRTs with partial penetrance. We have also shown that Snf5+/? mice that lack expression of the pRb family, due to TgT121 transgene expression, develop MRTs with increased penetrance and decreased latency. Here, we report that altering the genetic background has substantial effects upon MRT development in Snf5+/? and TgT121;Snf5+/? mice, with a mixed F1 background resulting in increased latency and the appearance of brain tumors. We also report the establishment of the first mouse MRT cell lines that recapitulate many features of their human counterparts. Our studies provide further insight into the genetic influences on MRT development as well as provide valuable new cell culture and genetically engineered mouse models for the study of CNS-MRT etiology.

Kuwahara, Yasumichi; Mora-Blanco, E Lorena; Banine, Fatima; Rogers, Arlin B.; Fletcher, Christopher; Sherman, Larry S.; Roberts, Charles W. M.; Weissman, Bernard E.

2012-01-01

328

Establishment and characterization of MRT cell lines from genetically engineered mouse models and the influence of genetic background on their development.  

PubMed

Malignant rhabdoid tumors (MRTs) are rare, aggressive cancers occuring in young children primarily through inactivation of the SNF5(INI1, SMARCB1) tumor suppressor gene. We and others have demonstrated that mice heterozygous for a Snf5 null allele develop MRTs with partial penetrance. We have also shown that Snf5(+/-) mice that lack expression of the pRb family, due to TgT121 transgene expression, develop MRTs with increased penetrance and decreased latency. Here, we report that altering the genetic background has substantial effects upon MRT development in Snf5(+/--) and TgT121 ;Snf5(+/-) mice, with a mixed F1 background resulting in increased latency and the appearance of brain tumors. We also report the establishment of the first mouse MRT cell lines that recapitulate many features of their human counterparts. Our studies provide further insight into the genetic influences on MRT development as well as provide valuable new cell culture and genetically engineered mouse models for the study of CNS-MRT etiology. PMID:23197309

Kuwahara, Yasumichi; Mora-Blanco, E Lorena; Banine, Fatima; Rogers, Arlin B; Fletcher, Christopher; Sherman, Larry S; Roberts, Charles W M; Weissman, Bernard E

2013-06-15

329

Genetic background of claw disorders in the course of lactation and their relationships with type traits.  

PubMed

Random regression threshold animal models were applied to binary longitudinal claw disorder data for studying genetic parameters of all claw disorders (ACD), as well as to claw disorders divided into different categories: non-purulent claw disorders (NPCD), purulent claw disorders (PCD), dermatitis digitalis (DD), sole ulcer (SU), phlegmona (PH), laminitis (LAM) and interdigital hyperplasia (IH) in the course of lactation. Claw disorder data were obtained from 26 651 Holstein cows kept in 15 large-scale contract herds in the region of Thuringia over a period of 5 years from 2007 to 2012. If a cow had one or more entries of the same disorder, for example, sole ulcer, within an interval of 30 days, she was scored with a '1', and otherwise, she received a score of '0' for healthy. Heritabilities for the same disorder were relatively stable between DIM 50 and DIM 300, but they tended to increase in early and late lactation. Highest heritabilities in the range from 0.20 to 0.34 were estimated for IH, and lowest heritabilities were realized for LAM (~ 0.05). Genetic correlations for same traits between different DIMs were high for adjacent test days, but close to zero for distant test days. The relationship between the sire EBVs for claw disorders and official sire EBVs for the type traits 'foot angle' was slightly antagonistic with correlation coefficients in the range from 0.05 (DD) to 0.33 (PH). Correlations between lactation EBVs for hock quality, rear leg rear view and the feet and leg index with EBVs for claw disorders were slightly favourable and ranged between -0.01 (rear leg rear view correlated with SU) and -0.43 (hock quality correlated with PH). Regarding daily EBVs for claw disorders, the strongest correlation coefficient was of value -0.46 (LAM early in lactation correlated with the feet and leg index). Genetic parameters from the random regression model were verified by applying a single-trait repeatability model. Correlation coefficients between lactation EBVs from the random regression model and lactation EBVs from the repeatability model for the same claw disorder were close to 1. Correlations were lower between EBVs from single test days and lactation EBVs from the repeatability models, with a minimal value of 0.58 for PCD measured at day 20. PMID:24236606

Gernand, E; Döhne, D A; König, S

2013-12-01

330

The role of catecholamines in seizure susceptibility: new results using genetically engineered mice  

Microsoft Academic Search

The catecholamines norepinephrine and dopamine are abundant in the CNS, and modulate neuronal excitability via G-protein-coupled receptor signaling. This review covers the history of research concerning the role of catecholamines in modulating seizure susceptibility in animal models of epilepsy. Traditionally, most work on this topic has been anatomical, pharmacological, or physiological in nature. However, the recent advances in transgenic and

David Weinshenker; Patricia Szot

2002-01-01

331

A candidate gene approach for the genetic analysis of susceptibility to tuberculosis  

Microsoft Academic Search

Tuberculosis is the most frequent and severe human disease caused by mycobacteria. In the mouse a candidate gene for innate resistance to mycobacteria (Bcg) was recently isolated and termed Nramp. We used SSCA and DNA sequencing to identify mutations in the human homologue, NRAMP, in chromosome region 2q35 in order to test if NRAMP contributes to susceptibility to tuberculosis. We

K. Morgan; J. Liu; L. Boothroyd

1994-01-01

332

Common and different genetic background for rheumatoid arthritis and coeliac disease.  

PubMed

Recent genome-wide association studies (GWAS) have revealed genetic risk factors in autoimmune and inflammatory disorders. Several of the associated genes and underlying pathways are shared by various autoimmune diseases. Rheumatoid arthritis (RA) and coeliac disease (CD) are two autoimmune disorders which have commonalities in their pathogenesis. We aimed to replicate known RA loci in a Dutch RA population, and to investigate whether the effect of known RA and CD risk factors generalize across the two diseases. We selected all loci associated to either RA or CD in a GWAS and confirmed in an independent cohort, with a combined P-value cut-off P < 5 x 10(-6). We genotyped 11 RA and 11 CD loci in 1368 RA patients, 795 CD patients and 1683 Dutch controls. We combined our results in a meta-analysis with UK GWAS on RA (1860 cases; 2938 controls) and CD (767 cases; 1422 controls). In the Dutch RA cohort, the PTPN22 and IL2/IL21 variants showed convincing association (P = 3.4 x 10(-12) and P = 2.8 x 10(-4), respectively). Association of RA with the known CD risk variant in the SH2B3 was also observed, predominantly in the subgroup of rheumatoid factor-positive RA patients (P = 0.0055). In a meta-analysis of Dutch and UK data sets, shared association with six loci (TNFAIP3, IL2/IL21, SH2B3, LPP, MMEL1/TNFRSF14 and PFKFB3/PRKCQ) was observed in both RA and CD cohorts. We confirmed two known loci and identified four novel ones for shared CD-RA genetic risk. Most of the shared loci further emphasize a role for adaptive and innate immunity in these diseases. PMID:19648290

Coenen, Marieke J H; Trynka, Gosia; Heskamp, Sandra; Franke, Barbara; van Diemen, Cleo C; Smolonska, Joanna; van Leeuwen, Miek; Brouwer, Elisabeth; Boezen, Marike H; Postma, Dirkje S; Platteel, Mathieu; Zanen, Pieter; Lammers, Jan-Willem W J; Groen, Harry J M; Mali, Willem P T M; Mulder, Chris J; Tack, Greetje J; Verbeek, Wieke H M; Wolters, Victorien M; Houwen, Roderick H J; Mearin, M Luisa; van Heel, David A; Radstake, Timothy R D J; van Riel, Piet L C M; Wijmenga, Cisca; Barrera, Pilar; Zhernakova, Alexandra

2009-11-01

333

HLA and Celiac Disease Susceptibility: New Genetic Factors Bring Open Questions about the HLA Influence and Gene-Dosage Effects  

PubMed Central

Celiac disease (CD) is a chronic inflammatory disorder triggered after gluten ingestion in genetically susceptible individuals. The major genetic determinants are HLA-DQA1*05 and HLA-DQB1*02, which encode the DQ2 heterodimer. These alleles are commonly inherited in cis with DRB1*03?01, which is associated with numerous immune-related disorders, in some cases contributing with a different amount of risk depending on the haplotype context. We aimed at investigating those possible differences involving DRB1*03?01-carrying haplotypes in CD susceptibility. A family (274 trios) and a case-control sample (369 CD cases/461 controls) were analyzed. DRB1*03?01-carrying individuals were classified according to the haplotype present (ancestral haplotype (AH) 8.1, AH 18.2 or non-conserved haplotype) after genotyping of HLA-DRB1, -DQA1, -DQB1, -B8, TNF -308, TNF -376 and the TNFa and TNFb microsatellites. We observe that the AH 8.1 confers higher risk than the remaining DRB1*03?01-carrying haplotypes, and this effect only involves individuals possessing a single copy of DQB1*02. CD risk for these individuals is similar to the one conferred by inherit DQA1*05 and DQB1*02 in trans. It seems that an additional CD susceptibility factor is present in the AH 8.1 but not in other DRB1*03?01-carrying haplotypes. This factor could be shared with individuals possessing DQ2.5 trans, according to the similar risk observed in those two groups of individuals.

Medrano, Luz Maria; Dema, Barbara; Lopez-Larios, Arturo; Maluenda, Carlos; Bodas, Andres; Lopez-Palacios, Natalia; Figueredo, M. Angeles; Fernandez-Arquero, Miguel; Nunez, Concepcion

2012-01-01

334

Identification of Genetic Susceptibility Loci for Colorectal Tumors in a Genome-wide Meta-analysis  

PubMed Central

BACKGROUND & AIMS Heritable factors contribute to the development of colorectal cancer. Identifying the genetic loci associated with colorectal tumor formation could elucidate the mechanisms of pathogenesis. METHODS We conducted a genome-wide association study that included 14 studies, 12,696 cases of colorectal tumors (11,870 cancer, 826 adenoma), and 15,113 controls of European descent. The 10 most statistically significant, previously unreported findings were followed up in 6 studies; these included 3056 colorectal tumor cases (2098 cancer, 958 adenoma) and 6658 controls of European and Asian descent. RESULTS Based on the combined analysis, we identified a locus that reached the conventional genome-wide significance level at less than 5.0 × 10?8: an intergenic region on chromosome 2q32.3, close to nucleic acid binding protein 1 (most significant single nucleotide polymorphism: rs11903757; odds ratio [OR], 1.15 per risk allele; P = 3.7 × 10?8). We also found evidence for 3 additional loci with P values less than 5.0 × 10?7: a locus within the laminin gamma 1 gene on chromosome 1q25.3 (rs10911251; OR, 1.10 per risk allele; P = 9.5 × 10?8), a locus within the cyclin D2 gene on chromosome 12p13.32 (rs3217810 per risk allele; OR, 0.84; P = 5.9 × 10?8), and a locus in the T-box 3 gene on chromosome 12q24.21 (rs59336; OR, 0.91 per risk allele; P = 3.7 × 10?7). CONCLUSIONS In a large genome-wide association study, we associated polymorphisms close to nucleic acid binding protein 1 (which encodes a DNA-binding protein involved in DNA repair) with colorectal tumor risk. We also provided evidence for an association between colorectal tumor risk and polymorphisms in laminin gamma 1 (this is the second gene in the laminin family to be associated with colorectal cancers), cyclin D2 (which encodes for cyclin D2), and T-box 3 (which encodes a T-box transcription factor and is a target of Wnt signaling to ?-catenin). The roles of these genes and their products in cancer pathogenesis warrant further investigation.

Peters, Ulrike; Jiao, Shuo; Schumacher, Fredrick R.; Hutter, Carolyn M.; Aragaki, Aaron K.; Baron, John A.; Berndt, Sonja I.; Bezieau, Stephane; Brenner, Hermann; Butterbach, Katja; Caan, Bette J.; Campbell, Peter T.; Carlson, Christopher S.; Casey, Graham; Chan, Andrew T.; Chang-Claude, Jenny; Chanock, Stephen J.; Chen, Lin S.; Coetzee, Gerhard A.; Coetzee, Simon G.; Conti, David V.; Curtis, Keith R.; Duggan, David; Edwards, Todd; Fuchs, Charles S.; Gallinger, Steven; Giovannucci, Edward L.; Gogarten, Stephanie M.; Gruber, Stephen B.; Haile, Robert W.; Harrison, Tabitha A.; Hayes, Richard B.; Henderson, Brian E.; Hoffmeister, Michael; Hopper, John L.; Hudson, Thomas J.; Hunter, David J.; Jackson, Rebecca D.; Jee, Sun Ha; Jenkins, Mark A.; Jia, Wei-Hua; Kolonel, Laurence N.; Kooperberg, Charles; Kury, Sebastien; Lacroix, Andrea Z.; Laurie, Cathy C.; Laurie, Cecelia A.; Le Marchand, Loic; Lemire, Mathieu; Levine, David; Lindor, Noralane M.; Liu, Yan; Ma, Jing; Makar, Karen W.; Matsuo, Keitaro; Newcomb, Polly A.; Potter, John D.; Prentice, Ross L.; Qu, Conghui; Rohan, Thomas; Rosse, Stephanie A.; Schoen, Robert E.; Seminara, Daniela; Shrubsole, Martha; Shu, Xiao-Ou; Slattery, Martha L.; Taverna, Darin; Thibodeau, Stephen N.; Ulrich, Cornelia M.; White, Emily; Xiang, Yongbing; Zanke, Brent W.; Zeng, Yi-Xin; Zhang, Ben; Zheng, Wei; Hsu, Li

2013-01-01

335

Association of GST Genetic Polymorphisms with the Susceptibility to Hepatocellular Carcinoma (HCC) in Chinese Population Evaluated by an Updated Systematic Meta-Analysis  

PubMed Central

Background Due to the possible involvement of Glutathione S-transferase Mu-1 (GSTM1) and Glutathione S-transferase theta-1 (GSTT1) in the detoxification of environmental carcinogens, environmental toxins, and oxidative stress products, genetic polymorphisms of these two genes may play important roles in the susceptibility of human being to hepatocellular carcinoma. However, the existing research results are not conclusive. Methods A systematic literature search using databases (PubMed, Scopus, Embase, Chinese Biomedical Database, Chinese National Knowledge Infrastructure, Wanfang Data, etc.) for the eligible studies meeting the inclusion criteria including case-control studies or cohort studies is evaluated using an updated systematic meta-analysis. Results Significant increase in the risk of HCC in the Chinese population is found in GSTM1 null genotype (OR?=?1.47, 95% CI: 1.21 to 1.79, P<0.001) and GSTT1 null genotype (OR?=?1.38, 95% CI: 1.14 to 1.65, P<0.001). Analysis using the random-effects model found an increased risk of HCC in GSTM1-GSTT1 dual null population (OR?=?1.79, 95% CI: 1.26 to 2.53, P<0.001). In addition, subgroup analyses showed a significant increase in the association of GST genetic polymorphisms (GSTM1, GSTT1, and GSTM1-GSTT1) with HCC in southeast and central China mainland. However, available data collected by this study fail to show an association between GST genetic polymorphisms and HCC in people from the Taiwan region (for GSTM1: OR?=?0.78, 95% CI: 0.60 to 1.01, P?=?0.06; for GSTT1: OR?=?0.94, 95% CI: 0.78 to 1.14, P?=?0.546; for GSTM1-GSTT1: OR?=?1.04, 95% CI: 0.81 to 1.32, P?=?0.77). Sensitivity analysis and publication bias diagnostics confirmed the reliability and stability of this meta-analysis. Conclusions Our results indicate that both GSTM1 and GSTT1 null genotypes are associated with an increased HCC risk in Chinese population. Peoples with dual null genotypes of GSTM1-GSTT1 are more susceptible to developing HCC. In conclusion, GST genetic polymorphisms play vital roles in the development of HCC in the Chinese population.

Liu, Kui; Zhang, Lu; Lin, Xialu; Chen, Liangliang; Shi, Hongbo; Magaye, Ruth; Zou, Baobo; Zhao, Jinshun

2013-01-01

336

Geographic Differences in Genetic Susceptibility to IgA Nephropathy: GWAS Replication Study and Geospatial Risk Analysis  

PubMed Central

IgA nephropathy (IgAN), major cause of kidney failure worldwide, is common in Asians, moderately prevalent in Europeans, and rare in Africans. It is not known if these differences represent variation in genes, environment, or ascertainment. In a recent GWAS, we localized five IgAN susceptibility loci on Chr.6p21 (HLA-DQB1/DRB1, PSMB9/TAP1, and DPA1/DPB2 loci), Chr.1q32 (CFHR3/R1 locus), and Chr.22q12 (HORMAD2 locus). These IgAN loci are associated with risk of other immune-mediated disorders such as type I diabetes, multiple sclerosis, or inflammatory bowel disease. We tested association of these loci in eight new independent cohorts of Asian, European, and African-American ancestry (N?=?4,789), followed by meta-analysis with risk-score modeling in 12 cohorts (N?=?10,755) and geospatial analysis in 85 world populations. Four susceptibility loci robustly replicated and all five loci were genome-wide significant in the combined cohort (P?=?5×10?32–3×10?10), with heterogeneity detected only at the PSMB9/TAP1 locus (I2?=?0.60). Conditional analyses identified two new independent risk alleles within the HLA-DQB1/DRB1 locus, defining multiple risk and protective haplotypes within this interval. We also detected a significant genetic interaction, whereby the odds ratio for the HORMAD2 protective allele was reversed in homozygotes for a CFHR3/R1 deletion (P?=?2.5×10?4). A seven–SNP genetic risk score, which explained 4.7% of overall IgAN risk, increased sharply with Eastward and Northward distance from Africa (r?=?0.30, P?=?3×10?128). This model paralleled the known East–West gradient in disease risk. Moreover, the prediction of a South–North axis was confirmed by registry data showing that the prevalence of IgAN–attributable kidney failure is increased in Northern Europe, similar to multiple sclerosis and type I diabetes. Variation at IgAN susceptibility loci correlates with differences in disease prevalence among world populations. These findings inform genetic, biological, and epidemiological investigations of IgAN and permit cross-comparison with other complex traits that share genetic risk loci and geographic patterns with IgAN.

Kiryluk, Krzysztof; Li, Yifu; Sanna-Cherchi, Simone; Rohanizadegan, Mersedeh; Suzuki, Hitoshi; Eitner, Frank; Snyder, Holly J.; Choi, Murim; Hou, Ping; Scolari, Francesco; Izzi, Claudia; Gigante, Maddalena; Gesualdo, Loreto; Savoldi, Silvana; Amoroso, Antonio; Cusi, Daniele; Zamboli, Pasquale; Julian, Bruce A.; Novak, Jan; Wyatt, Robert J.; Mucha, Krzysztof; Perola, Markus; Kristiansson, Kati; Viktorin, Alexander; Magnusson, Patrik K.; Thorleifsson, Gudmar; Thorsteinsdottir, Unnur; Stefansson, Kari; Boland, Anne; Metzger, Marie; Thibaudin, Lise; Wanner, Christoph; Jager, Kitty J.; Goto, Shin; Maixnerova, Dita; Karnib, Hussein H.; Nagy, Judit; Panzer, Ulf; Xie, Jingyuan; Chen, Nan; Tesar, Vladimir; Narita, Ichiei; Berthoux, Francois; Floege, Jurgen; Stengel, Benedicte; Zhang, Hong; Lifton, Richard P.; Gharavi, Ali G.

2012-01-01

337

IL2RA Genetic Heterogeneity in Multiple Sclerosis and Type 1 Diabetes Susceptibility and Soluble Interleukin-2 Receptor Production  

PubMed Central

Multiple sclerosis (MS) and type 1 diabetes (T1D) are organ-specific autoimmune disorders with significant heritability, part of which is conferred by shared alleles. For decades, the Human Leukocyte Antigen (HLA) complex was the only known susceptibility locus for both T1D and MS, but loci outside the HLA complex harboring risk alleles have been discovered and fully replicated. A genome-wide association scan for MS risk genes and candidate gene association studies have previously described the IL2RA gene region as a shared autoimmune locus. In order to investigate whether autoimmunity risk at IL2RA was due to distinct or shared alleles, we performed a genetic association study of three IL2RA variants in a DNA collection of up to 9,407 healthy controls, 2,420 MS, and 6,425 T1D subjects as well as 1,303 MS parent/child trios. Here, we report “allelic heterogeneity” at the IL2RA region between MS and T1D. We observe an allele associated with susceptibility to one disease and risk to the other, an allele that confers susceptibility to both diseases, and an allele that may only confer susceptibility to T1D. In addition, we tested the levels of soluble interleukin-2 receptor (sIL-2RA) in the serum from up to 69 healthy control subjects, 285 MS, and 1,317 T1D subjects. We demonstrate that multiple variants independently correlate with sIL-2RA levels.

Cooper, Jason; Downes, Kate; Anderson, David E.; Severson, Christopher; Clark, Pamela M.; Healy, Brian; Walker, Neil; Aubin, Cristin; Oksenberg, Jorge R.; Hauser, Stephen L.; Compston, Alistair; Sawcer, Stephen; De Jager, Philip L.; Wicker, Linda S.

2009-01-01

338

Molecular Epidemiology of Breast Cancer: Risk from Environmental Exposures and Genetic Susceptibility.  

National Technical Information Service (NTIS)

This postdoctoral research fellowship included a thorough investigation of genetic and environmental determinants of breast cancer risk. Major findings from this research include the following: (1) smoking may be an important risk factor for breast cancer...

K. B. Moysich

1998-01-01

339

Comprehensive Clinical Phenotyping and Genetic Mapping for the Discovery of Autism Susceptibility Genes.  

National Technical Information Service (NTIS)

Autism is an extremely common and heterogeneous neurodevelopmental disorder. While genetic factors are known to play a critical role in the etiologies of autism, the underlying genes and mechanisms remain unknown in approximately 70-75% of cases. Advances...

E. Hansen G. E. Herman M. B. Dewitt R. Smith W. Sadee

2013-01-01

340

Evaluation of genetic tests for susceptibility to common complex diseases: why, when and how?  

Microsoft Academic Search

Recent research into the human genome has generated a wealth of scientific knowledge and increased both public and professional\\u000a interest in the concept of personalised medicine. Somewhat unexpectedly, in addition to increasing our understanding about\\u000a the genetic basis for numerous diseases, these new discoveries have also spawned a burgeoning new industry of ‘consumer genetic\\u000a testing’. In this paper, we present

Caroline Fiona Wright; Mark Kroese

2010-01-01

341

Genetic susceptibility to male infertility: news from genome-wide association studies.  

PubMed

A thorough understanding of the genetic basis of male infertility has eluded researchers in spite of significant efforts to identify novel genetic causes of the disease, particularly over the past decade. Approximately half of male factor infertility cases have no known cause; however, it is likely that the majority of idiopathic male factor infertility cases have some unidentified genetic basis. Well-established genetic causes of male infertility are limited to Y chromosome microdeletions and Klinefelter's syndrome, together accounting for 10-20% of cases of severe spermatogenic failure. In addition to these, several genetic polymorphisms have been demonstrated to be significantly associated with male infertility. The discovery of new genetic associations with male infertility has been hampered by two primary factors. First, most studies are underpowered because of insufficient sample size and ethnic and phenotypic heterogeneity. Second, most studies evaluate a single gene, an approach that is very inefficient in the context of male infertility, considering that many hundreds of genes are involved in the process of testicular development and spermatogenesis. Significant recent advances in microarray and next-generation sequencing technologies have enabled the application of whole-genome approaches to the study of male infertility. We recently performed a pilot genome-wide association study (GWAS) for severe spermatogenic failure, and several additional male infertility GWAS have since been published. More recently, genomic microarray tools have been applied to the association of copy number variants with male infertility. These studies are beginning to shed additional light on the genetic architecture of male infertility, and whole-genome studies have proven effective in identifying novel genetic causes of the disease. This review will discuss some of the recent findings of these whole-genome studies as well as future directions for this research that will likely be the most productive moving forward. PMID:24574159

Aston, K I

2014-05-01

342

Genetic background influences adaptation to cardiac hypertrophy and Ca(2+) handling gene expression.  

PubMed

Genetic variability has a profound effect on the development of cardiac hypertrophy in response to stress. Consequently, using a variety of inbred mouse strains with known genetic profiles may be powerful models for studying the response to cardiovascular stress. To explore this approach we looked at male C57BL/6J and 129/SvJ mice. Hemodynamic analyses of left ventricular pressures (LVPs) indicated significant differences in 129/SvJ and C57BL/6J mice that implied altered Ca(2+) handling. Specifically, 129/SvJ mice demonstrated reduced rates of relaxation and insensitivity to dobutamine (Db). We hypothesized that altered expression of genes controlling the influx and efflux of Ca(2+) from the sarcoplasmic reticulum (SR) was responsible and investigated the expression of several genes involved in maintaining the intracellular and sarcoluminal Ca(2+) concentration using quantitative real-time PCR analyses (qRT-PCR). We observed significant differences in baseline gene expression as well as different responses in expression to isoproterenol (ISO) challenge. In untreated control animals, 129/SvJ mice expressed 1.68× more ryanodine receptor 2(Ryr2) mRNA than C57BL/6J mice but only 0.37× as much calsequestrin 2 (Casq2). After treatment with ISO, sarco(endo)plasmic reticulum Ca(2+)-ATPase(Serca2) expression was reduced nearly two-fold in 129/SvJ while expression in C57BL/6J was stable. Interestingly, ? (1) adrenergic receptor(Adrb1) expression was lower in 129/SvJ compared to C57BL/6J at baseline and lower in both strains after treatment. Metabolically, the brain isoform of creatine kinase (Ckb) was up-regulated in response to ISO in C57BL/6J but not in 129/SvJ. These data suggest that the two strains of mice regulate Ca(2+) homeostasis via different mechanisms and may be useful in developing personalized therapies in human patients. PMID:23508205

Waters, Steve B; Diak, Douglass M; Zuckermann, Matthew; Goldspink, Paul H; Leoni, Lara; Roman, Brian B

2013-01-01

343

[Molecular genetic background of developmental bony malformations at the craniocervical junction and cervical spine].  

PubMed

In this review a new interpretation of the origin of bony developmental malformations affecting the craniocervical junction and the cervical spine is presented based on recent advances in the understanding of embryonic development of the spine and its molecular genetic control. Radiographs, CT and MRI scans or CT myelograms of patients with Klippel-Feil syndrome were used for demonstration. Detailed clinical and radiological analysis of these patients was published earlier [David KM, Stevens JM, Thorogood P, Crockard HA. The dysmorphic cervical spine in Klippel-Feil syndrome: interpretations from developmental biology. Neurosurg Focus 1999;6(6):1.]. Homeotic transformation due to mutations or disturbed expression of Hox genes is a possible mechanism responsible for Cl assimilation. Notochordal defects and/or signalling problems, that result in reduced or impaired Pax-1 gene expression, may underlie vertebral fusions. This, together with asymmetrical distribution of paraxial mesoderm cells and a possible lack of communication across the embryonic mid-line, could cause the asymmetrical fusion patterns. The wide and flattened shape of the fused vertebral bodies, their resemblance to the embryonic cartilaginous vertebrae and the process of progressive bony fusion with age suggest that the fusions occur before or, at the latest, during chondrification of vertebrae. The authors suggest that the aforementioned mechanisms are likely to be, at least in part, responsible for the origin of the bony developmental malformations affecting the craniocervical junction and the cervical spine. PMID:12201233

Károly, Dávid; Kasó, Gábor; Thorogood, Peter V; Stevens, John M; Crockard, H Alan

2002-07-20

344

The genetic background of generalized pustular psoriasis: IL36RN mutations and CARD14 gain-of-function variants.  

PubMed

Generalized pustular psoriasis (GPP) is often present in patients with existing or prior psoriasis vulgaris (PV; "GPP with PV"). However, cases of GPP have been known to arise without a history of PV ("GPP alone"). There has long been debate over whether GPP alone and GPP with PV are distinct subtypes that are etiologically different from each other. We recently reported that the majority of GPP alone cases is caused by recessive mutations of IL36RN. In contrast, only a few exceptional cases of GPP with PV were found to have recessive IL36RN mutations. Very recently, we also reported that CARD14 p.Asp176His, a gain-of-function variant, is a predisposing factor for GPP with PV; in contrast, the variant is not associated with GPP alone in the Japanese population. These results suggest that GPP alone is genetically different from GPP with PV. IL36RN mutations are also found in some patients with severe acute generalized exanthematous pustulosis, palmar-plantar pustulosis, and acrodermatitis continua of hallopeau. CARD14 mutations and variants are causal or disease susceptibility factors of PV, GPP, or pityriasis rubra pilaris, depending on the mutation or variant position of CARD14. It is clinically important to analyze IL36RN mutations in patients with sterile pustulosis. For example, identifying recessive IL36RN mutations leads to early diagnosis of GPP, even at the first episode of pustulosis. In addition, individuals with IL36RN mutations are very susceptible to GPP or GPP-related generalized pustulosis induced by drugs (e.g., amoxicillin), infections, pregnancy, or menstruation. PMID:24656634

Sugiura, Kazumitsu

2014-06-01

345

Genetic Susceptibility to Squamous Cell Carcinoma of the Lung in Relation to Cigarette Smoking Dose1  

Microsoft Academic Search

Cytochrome P450IÁ1 is responsible for the metabolic activation of benzo(a)pyrene in cigarette smoke; an association of lung cancer with DNA polymorphisms of P450IA1 gene was shown in our previous study. In this paper, we investigated the interindividual difference of geneti cally determined susceptibility to squamous cell carcinoma of the lung in relation to cigarette smoking dose. We tirsi compared the

Kei Nakachi; Kazue Imai; Shin-ichi Hayashi; Junko Watanabe; Kaname Kawajiri

346

Genetic variants in the candidate genes of the apoptosis pathway and susceptibility to chronic myeloid leukemia.  

PubMed

Chronic myeloid leukemia (CML) is a clonal myeloproliferative disorder, characterized by the presence of BCR/ABL fusion gene. It is unclear which cellular events drive BCR/ABL gene translocation or initiate leukemogenesis in CML. Bcl-2 promotes survival of hematopoietic stem cells. Accordingly, apoptosis-related pathway may involve in the leukemogenesis of CML. In the current study, we evaluated 80 single nucleotide polymorphism (SNP) markers involved in the pathways of apoptosis (n = 30), angiogenesis (n = 7), myeloid cell growth (n = 14), xenobiotic metabolism (n = 13), WT1 signaling (n = 7), interferon signaling (n = 4), and others (n = 5) in 170 CML patients and 182 healthy controls. In a single-marker analysis, the following SNPs were identified including VEGFA, BCL2, CASP7, JAK3, CSF3, and HOCT1. In the multivariate logistic model with these SNPs and covariates, only BCL2 (rs1801018) was significantly associated with the susceptibility to CML (P = .05; odds ratio [OR] 2.16 [1.00-4.68]). In haplotype analyses, haplotype block of BCL2 consistently showed significant association with the susceptibility to CML. Risk allele analysis showed that a greater number of risk alleles from BCL2 SNP correlated to increasing risk of CML (overall P = .1, OR 1.84 [1.06-3.22] for 3-4 risk alleles vs 0-1 risk alleles). The current study indicated that BCL2 SNP seemed to be associated with increasing susceptibility to CML. PMID:19141860

Kim, Dong Hwan Dennis; Xu, Wei; Ma, Clement; Liu, Xiangdong; Siminovitch, Katherine; Messner, Hans A; Lipton, Jeffrey H

2009-03-12

347

Complex genetic control of susceptibility to malaria: positional cloning of the Char9 locus  

PubMed Central

Mouse strains AcB55 and AcB61 are resistant to malaria by virtue of a mutation in erythrocyte pyruvate kinase (PklrI90N). Linkage analysis in [AcB55 × A/J] F2 mice detected a second locus (Char9; logarithm of odds = 4.74) that regulates the blood-stage replication of Plasmodium chabaudi AS independently of Pklr. We characterized the 77 genes of the Char9 locus for tissue-specific expression, strain-specific alterations in gene expression, and polymorphic variants that are possibly associated with differential susceptibility. We identified Vnn1/Vnn3 as the likely candidates responsible for Char9. Vnn3/Vnn1 map within a conserved haplotype block and show expression levels that are strictly cis-regulated by this haplotype. The absence of Vnn messenger RNA expression and lack of pantetheinase protein activity in tissues are associated with susceptibility to malaria and are linked to a complex rearrangement in the Vnn3 promoter region. The A/J strain also carries a unique nonsense mutation that leads to a truncated protein. Vanin genes code for a pantetheinase involved in the production of cysteamine, a key regulator of host responses to inflammatory stimuli. Administration of cystamine in vivo partially corrects susceptibility to malaria in A/J mice, as measured by reduced blood parasitemia and decreased mortality. These studies suggest that pantetheinase is critical for the host response to malaria.

Min-Oo, Gundula; Fortin, Anny; Pitari, Giuseppina; Tam, Mifong; Stevenson, Mary M.; Gros, Philippe

2007-01-01

348

Genetic Susceptibility to Type 2 Diabetes and Obesity: Follow-Up of Findings from Genome-Wide Association Studies  

PubMed Central

Elucidating the underlying genetic variations influencing various complex diseases is one of the major challenges currently facing clinical genetic research. Although these variations are often difficult to uncover, approaches such as genome-wide association studies (GWASs) have been successful at finding statistically significant associations between specific genomic loci and disease susceptibility. GWAS has been especially successful in elucidating genetic variants that influence type 2 diabetes (T2D) and obesity/body mass index (BMI). Specifically, several GWASs have confirmed that a variant in transcription factor 7-like 2 (TCF7L2) confers risk for T2D, while a variant in fat mass and obesity-associated protein (FTO) confers risk for obesity/BMI; indeed both of these signals are considered the most statistically associated loci discovered for these respective traits to date. The discovery of these two key loci in this context has been invaluable for providing novel insight into mechanisms of heritability and disease pathogenesis. As follow-up studies of TCF7L2 and FTO have typically lead the way in how to follow up a GWAS discovery, we outline what has been learned from such investigations and how they have implications for the myriad of other loci that have been subsequently reported in this disease context.

Basile, Kevin J.; Johnson, Matthew E.; Xia, Qianghua; Grant, Struan F. A.

2014-01-01

349

BRCA1/2 genetic background-based therapeutic tailoring of human ovarian cancer: hope or reality?  

PubMed Central

Ovarian epithelial tumors are an hallmark of hereditary cancer syndromes which are related to the germ-line inheritance of cancer predisposing mutations in BRCA1 and BRCA2 genes. Although these genes have been associated with multiple different physiologic functions, they share an important role in DNA repair mechanisms and therefore in the whole genomic integrity control. These findings have risen a variety of issues in terms of treatment and prevention of breast and ovarian tumors arising in this context. Enhanced sensitivity to platinum-based anticancer drugs has been related to BRCA1/2 functional loss. Retrospective studies disclosed differential chemosensitivity profiles of BRCA1/2-related as compared to "sporadic" ovarian cancer and led to the identification of a "BRCA-ness" phenotype of ovarian cancer, which includes inherited BRCA1/2 germ-line mutations, a serous high grade histology highly sensitive to platinum derivatives. Molecularly-based tailored treatments of human tumors are an emerging issue in the "era" of molecular targeted drugs and molecular profiling technologies. We will critically discuss if the genetic background of ovarian cancer can indeed represent a determinant issue for decision making in the treatment selection and how the provocative preclinical findings might be translated in the therapeutic scenario. The presently available preclinical and clinical evidence clearly indicates that genetic background has an emerging role in treatment individualization for ovarian cancer patients.

Tagliaferri, Pierosandro; Ventura, Monica; Baudi, Francesco; Cucinotto, Iole; Arbitrio, Mariamena; Di Martino, Maria Teresa; Tassone, Pierfrancesco

2009-01-01

350

The genetic susceptibility to type 2 diabetes may be modulated by obesity status: implications for association studies  

Microsoft Academic Search

BACKGROUND: Considering that a portion of the heterogeneity amongst previous replication studies may be due to a variable proportion of obese subjects in case-control designs, we assessed the association of genetic variants with type 2 diabetes (T2D) in large groups of obese and non-obese subjects. METHODS: We genotyped RETN, KCNJ11, HNF4A, HNF1A, GCK, SLC30A8, ENPP1, ADIPOQ, PPARG, and TCF7L2 polymorphisms

Stéphane Cauchi; Kevin T Nead; Hélène Choquet; Fritz Horber; Natascha Potoczna; Beverley Balkau; Michel Marre; Guillaume Charpentier; Philippe Froguel; David Meyre

2008-01-01

351

Genetic Polymorphisms in CYP2E1: Association with Schizophrenia Susceptibility and Risperidone Response in the Chinese Han Population  

Microsoft Academic Search

BackgroundCYP2E1 is a member of the cytochrome P450 superfamily, which is involved in the metabolism and activation of both endobiotics and xenobiotics. The genetic polymorphisms of CYP2E1 gene (Chromosome 10q26.3, Accession Number NC_000010.10) are reported to be related to the development of several mental diseases and to be involved in the clinical efficacy of some psychiatric medications. We investigated the

Ran Huo; Kefu Tang; Zhiyun Wei; Lu Shen; Yuyu Xiong; Xi Wu; Jiamin Niu; Xia Han; Zhengan Tian; Lun Yang; Guoyin Feng; Lin He; Shengying Qin

2012-01-01

352

Spontaneous lupus-like syndrome in HLA-DQ2 Transgenic Mice with a Mixed Genetic Background  

PubMed Central

To investigate the role of HLA-DQ2 in the pathogenesis of associated immune disorders, we generated transgenic mice that expressed HLA-DQ2 in the absence of endogenous murine class II molecules (AE°DQ2). These AE°DQ2 mice with a mixed genetic background spontaneously developed skin lesions on their ears, whereas control AE°DQ6 genotype control mice (also with a mixed genetic background) did not. The skin lesions were characterized by deep subepidermal blistering with hydropic degeneration and lymphoid infiltration in the subepidermal area as determined by histopathology. Immunofluorescence analysis revealed thick band-like granular deposition of IgG, IgM, and a thin band of IgA deposition along the basement membrane. AE°DQ2 mice also developed significant and progressive hematuria and proteinuria as compared to the AE°DQ6 mice (P<0.05). Histopathology showed immune complex deposits in the glomeruli of AE°DQ2 mice. Immunofluorescence analysis showed progressive mesangial and capillary wall deposition of IgA, IgM, IgG and C1q in the kidney. With electron microscopy, the deposits showed a “fingerprint” substructure; and tubuloreticular structures were identified within endothelial cells. Conversely, these changes were not observed in AE°DQ6 mice. Serum anti-dsDNA IgM and IgG levels were also significantly elevated among AE°DQ2 mice compared to AE°DQ6 mice (P<0.001). In conclusion, AE°DQ2 mice spontaneously develop an autoimmune lupus-like syndrome and are useful model for this disease. It remains to be determined whether genetic admixture played a role in the development of this SLE-like syndrome in HLA-DQ2 transgenic mice.

Rashtak, Shadi; Marietta, Eric; Cheng, Shen; Camilleri, Michael; Pittelkow, Mark; David, Chella; Grande, Joseph; Murray, Joseph

2010-01-01

353

Maize centromeres expand and adopt a uniform size in the genetic background of oat  

PubMed Central

Most existing centromeres may have originated as neocentromeres that activated de novo from noncentromeric regions. However, the evolutionary path from a neocentromere to a mature centromere has been elusive. Here we analyzed the centromeres of nine chromosomes that were transferred from maize into oat as the result of an inter-species cross. Centromere size and location were assayed by chromatin immunoprecipitation for the histone variant CENH3, which is a defining feature of functional centromeres. Two isolates of maize chromosome 3 proved to contain neocentromeres in the sense that they had moved from the original site, whereas the remaining seven centromeres (1, 2, 5, 6, 8, 9, and 10) were retained in the same area in both species. In all cases, the CENH3-binding domains were dramatically expanded to encompass a larger area in the oat background (?3.6 Mb) than the average centromere size in maize (?1.8 Mb). The expansion of maize centromeres appeared to be restricted by the transcription of genes located in regions flanking the original centromeres. These results provide evidence that (1) centromere size is regulated; (2) centromere sizes tend to be uniform within a species regardless of chromosome size or origin of the centromere; and (3) neocentromeres emerge and expand preferentially in gene-poor regions. Our results suggest that centromere size expansion may be a key factor in the survival of neocentric chromosomes in natural populations.

Wang, Kai; Wu, Yufeng; Zhang, Wenli; Dawe, R. Kelly; Jiang, Jiming

2014-01-01

354

Impact of Gene Patents and Licensing Practices on Access to Genetic Testing for Inherited Susceptibility to Cancer: Comparing Breast and Ovarian Cancers to Colon Cancers  

PubMed Central

Genetic testing for inherited susceptibility to breast and ovarian cancer can be compared to similar testing for colorectal cancer as a “natural experiment.” Inherited susceptibility accounts for a similar fraction of both cancers and genetic testing results guide decisions about options for prophylactic surgery in both sets of conditions. One major difference is that in the United States, Myriad Genetics is the sole provider of genetic testing, because it has sole control of relevant patents for BRCA1 and BRCA2 genes whereas genetic testing for familial colorectal cancer is available from multiple laboratories. Colorectal cancer-associated genes are also patented, but they have been nonexclusively licensed. Prices for BRCA1 and 2 testing do not reflect an obvious price premium attributable to exclusive patent rights compared to colorectal cancer testing, and indeed Myriad’s per unit costs are somewhat lower for BRCA1/2 testing than testing for colorectal cancer susceptibility. Myriad has not enforced patents against basic research, and negotiated a Memorandum of Understanding with the National Cancer Institute in 1999 for institutional BRCA testing in clinical research. The main impact of patenting and licensing in BRCA compared to colorectal cancer is the business model of genetic testing, with a sole provider for BRCA and multiple laboratories for colorectal cancer genetic testing. Myriad’s sole provider model has not worked in jurisdictions outside the United States, largely because of differences in breadth of patent protection, responses of government health services, and difficulty in patent enforcement.

Cook-Deegan, Robert; DeRienzo, Christopher; Carbone, Julia; Chandrasekharan, Subhashini; Heaney, Christopher; Conover, Christopher

2011-01-01

355

Impact of gene patents and licensing practices on access to genetic testing for inherited susceptibility to cancer: comparing breast and ovarian cancers with colon cancers.  

PubMed

Genetic testing for inherited susceptibility to breast and ovarian cancer can be compared with similar testing for colorectal cancer as a "natural experiment." Inherited susceptibility accounts for a similar fraction of both cancers and genetic testing results guide decisions about options for prophylactic surgery in both sets of conditions. One major difference is that in the United States, Myriad Genetics is the sole provider of genetic testing, because it has sole control of relevant patents for BRCA1 and BRCA2 genes, whereas genetic testing for familial colorectal cancer is available from multiple laboratories. Colorectal cancer-associated genes are also patented, but they have been nonexclusively licensed. Prices for BRCA1 and 2 testing do not reflect an obvious price premium attributable to exclusive patent rights compared with colorectal cancer testing, and indeed, Myriad's per unit costs are somewhat lower for BRCA1/2 testing than testing for colorectal cancer susceptibility. Myriad has not enforced patents against basic research and negotiated a Memorandum of Understanding with the National Cancer Institute in 1999 for institutional BRCA testing in clinical research. The main impact of patenting and licensing in BRCA compared with colorectal cancer is the business model of genetic testing, with a sole provider for BRCA and multiple laboratories for colorectal cancer genetic testing. Myriad's sole-provider model has not worked in jurisdictions outside the United States, largely because of differences in breadth of patent protection, responses of government health services, and difficulty in patent enforcement. PMID:20393305

Cook-Deegan, Robert; DeRienzo, Christopher; Carbone, Julia; Chandrasekharan, Subhashini; Heaney, Christopher; Conover, Christopher

2010-04-01

356

Genetic susceptibility to type 2 diabetes and obesity: from genome-wide association studies to rare variants and beyond.  

PubMed

During the past 7 years, genome-wide association studies have shed light on the contribution of common genomic variants to the genetic architecture of type 2 diabetes, obesity and related intermediate phenotypes. The discoveries have firmly established more than 175 genomic loci associated with these phenotypes. Despite the tight correlation between type 2 diabetes and obesity, these conditions do not appear to share a common genetic background, since they have few genetic risk loci in common. The recent genetic discoveries do however highlight specific details of the interplay between the pathogenesis of type 2 diabetes, insulin resistance and obesity. The focus is currently shifting towards investigations of data from targeted array-based genotyping and exome and genome sequencing to study the individual and combined effect of low-frequency and rare variants in metabolic disease. Here we review recent progress as regards the concepts, methodologies and derived outcomes of studies of the genetics of type 2 diabetes and obesity, and discuss avenues to be investigated in the future within this research field. PMID:24859358

Grarup, Niels; Sandholt, Camilla H; Hansen, Torben; Pedersen, Oluf

2014-08-01

357

Lymphocyte Deficiencies Increase Susceptibility to Friend Virus-Induced Erythroleukemia in Fv2 Genetically Resistant Mice  

Microsoft Academic Search

The study of genetic resistance to retroviral diseases provides insights into the mechanisms by which organisms overcome potentially lethal infections. Fv-2 resistance to Friend virus-induced erythroleukemia acts through nonimmunological mechanisms to prevent early virus spread, but it does not completely block infection. The current experiments were done to determine whether Fv-2 alone could provide resistance or whether immunological mechanisms were

KIM J. HASENKRUG

1999-01-01

358

Genetic Determinants of Susceptibility to UV Light-Associated Skin Cancer  

Microsoft Academic Search

UV light exposure has been incriminated for the steady rise in skin cancer incidence observed during the last years. However, individual responses to the oncogenic effects of UV light are greatly variable. Among the many factors modulating the response to UV light, genetic variations play a pivotal role. This review examines major progress in our understanding of major hereditary and

Eli Sprecher

2004-01-01

359

Dopaminergic Pathway Gene Polymorphisms and Genetic Susceptibility to Schizophrenia among North Indians  

Microsoft Academic Search

Objective: Understanding the etiology and pathogenesis of schizophrenia has been difficult due to the complex inheritance patterns, genetic heterogeneity and varied multiple nonlinear interactions between genes. Several lines of evidence indicate the involvement of neurotransmitter dopamine in the pathophysiology of this disorder. To analyze such a possible role of dopaminergic pathway gene polymorphisms, we used a case-control approach. Method: We

Vibhuti Srivastava; Smita N. Deshpande; B. K. Thelma

2010-01-01

360

Molecular Epidemiology of Breast Cancer: Risk from Environmental Exposures and Genetic Susceptibility.  

National Technical Information Service (NTIS)

This work is a continuation of the effort to determine environmental and genetic determinants of breast cancer. Since the last report data on serum organochlorine levels, e.g. serum DDE, HCB, total PCBs, and mirex, became available. These data were explor...

K. Moysich

1996-01-01