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Sample records for inter-individual genetic differences

  1. Genes: Interactions with Language on Three Levels—Inter-Individual Variation, Historical Correlations and Genetic Biasing

    NASA Astrophysics Data System (ADS)

    Dediu, Dan

    The complex inter-relationships between genetics and linguistics encompass all four scales highlighted by the contributions to this book and, together with cultural transmission, the genetics of language holds the promise to offer a unitary understanding of this fascinating phenomenon. There are inter-individual differences in genetic makeup which contribute to the obvious fact that we are not identical in the way we understand and use language and, by studying them, we will be able to both better treat and enhance ourselves. There are correlations between the genetic configuration of human groups and their languages, reflecting the historical processes shaping them, and there also seem to exist genes which can influence some characteristics of language, biasing it towards or against certain states by altering the way language is transmitted across generations. Besides the joys of pure knowledge, the understanding of these three aspects of genetics relevant to language will potentially trigger advances in medicine, linguistics, psychology or the understanding of our own past and, last but not least, a profound change in the way we regard one of the emblems of being human: our capacity for language.

  2. Inter-individual Variability in Soccer Players of Different Age Groups Playing Different Positions

    PubMed Central

    Nikolaidis, Pantelis; Ziv, Gal; Lidor, Ronnie; Arnon, Michal

    2014-01-01

    The purpose of this study was twofold: (a) to profile physical characteristics and motor abilities of three age groups of soccer players – under 14 years, 14–17, and over 17, playing different positions – goalkeepers, defenders, midfielders, and forwards; and (b) to examine the inter-individual variability among the players in each age group in all physical and physiological measurements performed in the study. In addition, anthropometric, power, strength, and flexibility tests were administered. Findings showed large inter-individual variability in all three age groups and in all playing positions. Differences between playing positions were found only in the 14–17 group (body mass) and in the over-17 group (body height, body mass, fat-free mass, and mean power in the Wingate Anaerobic Test). Due to the observed large inter-individual variability, it was concluded that the findings obtained in the physical and physiological tests should be interpreted with caution when attempting to differentiate between successful and unsuccessful soccer players, as well as when trying to predict future success in soccer. PMID:25031689

  3. Inter-individual variability and genetic influences on cytokine responses to bacteria and fungi.

    PubMed

    Li, Yang; Oosting, Marije; Deelen, Patrick; Ricaño-Ponce, Isis; Smeekens, Sanne; Jaeger, Martin; Matzaraki, Vasiliki; Swertz, Morris A; Xavier, Ramnik J; Franke, Lude; Wijmenga, Cisca; Joosten, Leo A B; Kumar, Vinod; Netea, Mihai G

    2016-08-01

    Little is known about the inter-individual variation of cytokine responses to different pathogens in healthy individuals. To systematically describe cytokine responses elicited by distinct pathogens and to determine the effect of genetic variation on cytokine production, we profiled cytokines produced by peripheral blood mononuclear cells from 197 individuals of European origin from the 200 Functional Genomics (200FG) cohort in the Human Functional Genomics Project (http://www.humanfunctionalgenomics.org), obtained over three different years. We compared bacteria- and fungi-induced cytokine profiles and found that most cytokine responses were organized around a physiological response to specific pathogens, rather than around a particular immune pathway or cytokine. We then correlated genome-wide single-nucleotide polymorphism (SNP) genotypes with cytokine abundance and identified six cytokine quantitative trait loci (QTLs). Among them, a cytokine QTL at the NAA35-GOLM1 locus markedly modulated interleukin (IL)-6 production in response to multiple pathogens and was associated with susceptibility to candidemia. Furthermore, the cytokine QTLs that we identified were enriched among SNPs previously associated with infectious diseases and heart diseases. These data reveal and begin to explain the variability in cytokine production by human immune cells in response to pathogens. PMID:27376574

  4. Intra- and inter-individual differences in human sperm DNA methylation.

    PubMed

    Dere, E; Huse, S; Hwang, K; Sigman, M; Boekelheide, K

    2016-09-01

    There is growing evidence that sperm DNA methylation is important in maintaining proper sperm health and function. Previous studies have associated sperm DNA methylation levels with sperm quality and function, however, little is known regarding the intra- and inter-individual variability in sperm methylation levels. This study characterizes this variation. Sperm epigenetic differences between successive semen samples from 12 patients were examined to identify the intra- and inter-individual differences globally across the genome, and in specifically defined genomic regions using the Illumina Infinium HumanMethylation450 BeadChips. Methylation analysis identified a bimodal distribution in the methylation levels that were non-uniformly distributed across the different genomic regions. The methylation levels were highly correlated in both the intra- and inter-individual comparisons. The intra-individual methylation levels were more highly correlated than the inter-individual comparison both globally and across the defined genomic regions, demonstrating that sperm DNA methylation levels are relatively stable between semen sample collections. PMID:27089098

  5. Inter Individual Variations of the Fish Skin Microbiota: Host Genetics Basis of Mutualism?

    PubMed Central

    Boutin, Sébastien; Sauvage, Christopher; Bernatchez, Louis; Audet, Céline; Derome, Nicolas

    2014-01-01

    The commensal microbiota of fish skin is suspected to provide a protection against opportunist infections. The skin of fish harbors a complex and diverse microbiota that closely interacts with the surrounding water microbial communities. Up to now there is no clear evidence as to whether the host regulates the recruitment of environmental bacteria to build a specific skin microbiota. To address this question, we detected Quantitative Trait Loci (QTL) associated with the abundance of specific skin microbiota bacterial strains in brook charr (Salvelinus fontinalis), combining 16S RNA tagged-amplicon 454 pyrosequencing with genetic linkage analysis. Skin microbiota analysis revealed high inter-individual variation among 86 F2 fish progeny based upon the relative abundance of bacterial operational taxonomic units (OTUs). Out of those OTUs, the pathogenic strain Flavobacterium psychrophilum and the non-pathogenic strain Methylobacterium rhodesianum explained the majority of inter-individual distances. Furthermore, a strong negative correlation was found between Flavobacterium and Methylobacterium, suggesting a mutually competitive relationship. Finally, after considering a total of 266 markers, genetic linkage analysis highlighted three major QTL associated with the abundance of Lysobacter, Rheinheimera and Methylobacterium. All these three genera are known for their beneficial antibacterial activity. Overall, our results provide evidence that host genotype may regulate the abundance of specific genera among their surface microbiota. They also indicate that Lysobacter, Rheinheimera and Methylobacterium are potentially important genera in providing protection against pathogens. PMID:25068850

  6. Solving the puzzle of collective action through inter-individual differences

    PubMed Central

    von Rueden, Chris; Gavrilets, Sergey; Glowacki, Luke

    2015-01-01

    Models of collective action infrequently account for differences across individuals beyond a limited set of strategies, ignoring variation in endowment (e.g. physical condition, wealth, knowledge, personality, support), individual costs of effort, or expected gains from cooperation. However, behavioural research indicates these inter-individual differences can have significant effects on the dynamics of collective action. The papers contributed to this theme issue evaluate how individual differences affect the propensity to cooperate, and how they can catalyse others’ likelihood of cooperation (e.g. via leadership). Many of the papers emphasize the relationship between individual decisions and socio-ecological context, particularly the effect of group size. All together, the papers in this theme issue provide a more complete picture of collective action, by embracing the reality of inter-individual variation and its multiple roles in the success or failure of collective action. PMID:26503677

  7. Solving the puzzle of collective action through inter-individual differences.

    PubMed

    von Rueden, Chris; Gavrilets, Sergey; Glowacki, Luke

    2015-12-01

    Models of collective action infrequently account for differences across individuals beyond a limited set of strategies, ignoring variation in endowment (e.g. physical condition, wealth, knowledge, personality, support), individual costs of effort, or expected gains from cooperation. However, behavioural research indicates these inter-individual differences can have significant effects on the dynamics of collective action. The papers contributed to this theme issue evaluate how individual differences affect the propensity to cooperate, and how they can catalyse others' likelihood of cooperation (e.g. via leadership). Many of the papers emphasize the relationship between individual decisions and socio-ecological context, particularly the effect of group size. All together, the papers in this theme issue provide a more complete picture of collective action, by embracing the reality of inter-individual variation and its multiple roles in the success or failure of collective action. PMID:26503677

  8. Inter-Individual Differences in RNA Levels in Human Peripheral Blood

    PubMed Central

    Chomczynski, Piotr; Wilfinger, William W.; Eghbalnia, Hamid R.; Kennedy, Amy; Rymaszewski, Michal; Mackey, Karol

    2016-01-01

    Relatively little is known about the range of RNA levels in human blood. This report provides assessment of peripheral blood RNA level and its inter-individual differences in a group of 35 healthy humans consisting of 25 females and 10 males ranging in age from 50 to 89 years. In this group, the average total RNA level was 14.59 μg/ml of blood, with no statistically significant difference between females and males. The individual RNA level ranged from 6.7 to 22.7 μg/ml of blood. In healthy subjects, the repeated sampling of an individual’s blood showed that RNA level, whether high or low, was stable. The inter-individual differences in RNA level in blood can be attributed to both, differences in cell number and the amount of RNA per cell. The 3.4-fold range of inter-individual differences in total RNA levels, documented herein, should be taken into account when evaluating the results of quantitative RT-PCR and/or RNA sequencing studies of human blood. Based on the presented results, a comprehensive assessment of gene expression in blood should involve determination of both the amount of mRNA per unit of total RNA (U / ng RNA) and the amount of mRNA per unit of blood (U / ml blood) to assure a thorough interpretation of physiological or pathological relevance of study results. PMID:26863434

  9. Amygdala volume predicts inter-individual differences in fearful face recognition.

    PubMed

    Zhao, Ke; Yan, Wen-Jing; Chen, Yu-Hsin; Zuo, Xi-Nian; Fu, Xiaolan

    2013-01-01

    The present study investigates the relationship between inter-individual differences in fearful face recognition and amygdala volume. Thirty normal adults were recruited and each completed two identical facial expression recognition tests offline and two magnetic resonance imaging (MRI) scans. Linear regression indicated that the left amygdala volume negatively correlated with the accuracy of recognizing fearful facial expressions and positively correlated with the probability of misrecognizing fear as surprise. Further exploratory analyses revealed that this relationship did not exist for any other subcortical or cortical regions. Nor did such a relationship exist between the left amygdala volume and performance recognizing the other five facial expressions. These mind-brain associations highlight the importance of the amygdala in recognizing fearful faces and provide insights regarding inter-individual differences in sensitivity toward fear-relevant stimuli. PMID:24009767

  10. Amygdala Volume Predicts Inter-Individual Differences in Fearful Face Recognition

    PubMed Central

    Zhao, Ke; Yan, Wen-Jing; Chen, Yu-Hsin; Zuo, Xi-Nian; Fu, Xiaolan

    2013-01-01

    The present study investigates the relationship between inter-individual differences in fearful face recognition and amygdala volume. Thirty normal adults were recruited and each completed two identical facial expression recognition tests offline and two magnetic resonance imaging (MRI) scans. Linear regression indicated that the left amygdala volume negatively correlated with the accuracy of recognizing fearful facial expressions and positively correlated with the probability of misrecognizing fear as surprise. Further exploratory analyses revealed that this relationship did not exist for any other subcortical or cortical regions. Nor did such a relationship exist between the left amygdala volume and performance recognizing the other five facial expressions. These mind-brain associations highlight the importance of the amygdala in recognizing fearful faces and provide insights regarding inter-individual differences in sensitivity toward fear-relevant stimuli. PMID:24009767

  11. Inter-Individual Differences in Neurobehavioural Impairment following Sleep Restriction Are Associated with Circadian Rhythm Phase

    PubMed Central

    Sletten, Tracey L.; Segal, Ahuva Y.; Flynn-Evans, Erin E.; Lockley, Steven W.; Rajaratnam, Shantha M. W.

    2015-01-01

    Although sleep restriction is associated with decrements in daytime alertness and neurobehavioural performance, there are considerable inter-individual differences in the degree of impairment. This study examined the effects of short-term sleep restriction on neurobehavioural performance and sleepiness, and the associations between individual differences in impairments and circadian rhythm phase. Healthy adults (n = 43; 22 M) aged 22.5 ± 3.1 (mean ± SD) years maintained a regular 8:16 h sleep:wake routine for at least three weeks prior to laboratory admission. Sleep opportunity was restricted to 5 hours time-in-bed at home the night before admission and 3 hours time-in-bed in the laboratory, aligned by wake time. Hourly saliva samples were collected from 5.5 h before until 5 h after the pre-laboratory scheduled bedtime to assess dim light melatonin onset (DLMO) as a marker of circadian phase. Participants completed a 10-min auditory Psychomotor Vigilance Task (PVT), the Karolinska Sleepiness Scale (KSS) and had slow eye movements (SEM) measured by electrooculography two hours after waking. We observed substantial inter-individual variability in neurobehavioural performance, particularly in the number of PVT lapses. Increased PVT lapses (r = -0.468, p < 0.01), greater sleepiness (r = 0.510, p < 0.0001), and more slow eye movements (r = 0.375, p = 0.022) were significantly associated with later DLMO, consistent with participants waking at an earlier circadian phase. When the difference between DLMO and sleep onset was less than 2 hours, individuals were significantly more likely to have at least three attentional lapses the following morning. This study demonstrates that the phase of an individual’s circadian system is an important variable in predicting the degree of neurobehavioural performance impairment in the hours after waking following sleep restriction, and confirms that other factors influencing performance decrements require further investigation. PMID

  12. Inter-Individual Differences in Neurobehavioural Impairment following Sleep Restriction Are Associated with Circadian Rhythm Phase.

    PubMed

    Sletten, Tracey L; Segal, Ahuva Y; Flynn-Evans, Erin E; Lockley, Steven W; Rajaratnam, Shantha M W

    2015-01-01

    Although sleep restriction is associated with decrements in daytime alertness and neurobehavioural performance, there are considerable inter-individual differences in the degree of impairment. This study examined the effects of short-term sleep restriction on neurobehavioural performance and sleepiness, and the associations between individual differences in impairments and circadian rhythm phase. Healthy adults (n = 43; 22 M) aged 22.5 ± 3.1 (mean ± SD) years maintained a regular 8:16 h sleep:wake routine for at least three weeks prior to laboratory admission. Sleep opportunity was restricted to 5 hours time-in-bed at home the night before admission and 3 hours time-in-bed in the laboratory, aligned by wake time. Hourly saliva samples were collected from 5.5 h before until 5 h after the pre-laboratory scheduled bedtime to assess dim light melatonin onset (DLMO) as a marker of circadian phase. Participants completed a 10-min auditory Psychomotor Vigilance Task (PVT), the Karolinska Sleepiness Scale (KSS) and had slow eye movements (SEM) measured by electrooculography two hours after waking. We observed substantial inter-individual variability in neurobehavioural performance, particularly in the number of PVT lapses. Increased PVT lapses (r = -0.468, p < 0.01), greater sleepiness (r = 0.510, p < 0.0001), and more slow eye movements (r = 0.375, p = 0.022) were significantly associated with later DLMO, consistent with participants waking at an earlier circadian phase. When the difference between DLMO and sleep onset was less than 2 hours, individuals were significantly more likely to have at least three attentional lapses the following morning. This study demonstrates that the phase of an individual's circadian system is an important variable in predicting the degree of neurobehavioural performance impairment in the hours after waking following sleep restriction, and confirms that other factors influencing performance decrements require further investigation. PMID

  13. Investigating inter-individual differences in short-term intra-individual variability

    PubMed Central

    Wang, Lijuan (Peggy); Hamaker, Ellen; Bergeman, C. S.

    2012-01-01

    Intra-individual variability over a short period of time may contain important information about how individuals differ from each other. In this paper we begin by discussing diverse indicators for quantifying intra-individual variability and indicate their advantages and disadvantages. Then we propose an alternative method that models inter-individual differences in intra-individual variability by separately considering both the amplitude of fluctuations and temporal dependency in the data. In the proposed model, temporal dependency and amplitude of fluctuations are both included as random effects. Parameter estimation is done with a multiple-step approach using maximum likelihood, or with a recommended one-step approach using a Bayesian method. The similarity and differences between the proposed method and some existing methods are discussed and investigated using diary study data from older adults. The results from empirical data analysis revealed that temporal dependency and amplitude of fluctuations have different predictability of health outcomes and thus should be modeled and considered separately. PMID:22924600

  14. Empathy matters: ERP evidence for inter-individual differences in social language processing

    PubMed Central

    Van Berkum, Jos J.A.; Bastiaansen, Marcel C.M.; Tesink, Cathelijne M.J.Y.; Kos, Miriam; Buitelaar, Jan K.; Hagoort, Peter

    2012-01-01

    When an adult claims he cannot sleep without his teddy bear, people tend to react surprised. Language interpretation is, thus, influenced by social context, such as who the speaker is. The present study reveals inter-individual differences in brain reactivity to social aspects of language. Whereas women showed brain reactivity when stereotype-based inferences about a speaker conflicted with the content of the message, men did not. This sex difference in social information processing can be explained by a specific cognitive trait, one’s ability to empathize. Individuals who empathize to a greater degree revealed larger N400 effects (as well as a larger increase in γ-band power) to socially relevant information. These results indicate that individuals with high-empathizing skills are able to rapidly integrate information about the speaker with the content of the message, as they make use of voice-based inferences about the speaker to process language in a top-down manner. Alternatively, individuals with lower empathizing skills did not use information about social stereotypes in implicit sentence comprehension, but rather took a more bottom-up approach to the processing of these social pragmatic sentences. PMID:21148175

  15. Flexibility of Physiological Traits Underlying Inter-Individual Growth Differences in Intertidal and Subtidal Mussels Mytilusgalloprovincialis

    PubMed Central

    Fernández-Reiriz, María José; Irisarri, Jade; Labarta, Uxio

    2016-01-01

    Mussel seed (Mytilusgalloprovincialis) gathered from the intertidal and subtidal environments of a Galician embayment (NW, Spain) were maintained in the laboratory during five months to select fast (F) and slow (S) growing mussels. The physiological basis underlying inter-individual growth variations were compared for F and S mussels from both origins. Fast growing seemed to be a consequence of greater energy intake (20% higher clearance and ingestion rate) and higher food absorption rate coupled with low metabolic costs. The enhanced energy absorption (around 65% higher) resulted in 3 times higher Scope for Growth in F mussels (20.5±4.9 J h−1) than S individuals (7.3±1.1 J h−1). The higher clearance rate of F mussels appears to be linked with larger gill filtration surface compared to S mussels. Intertidal mussels showed higher food acquisition and absorption per mg of organic weight (i.e. mass-specific standardization) than subtidal mussels under the optimal feeding conditions of the laboratory. However, the enhanced feeding and digestive rates were not enough to compensate for the initial differences in tissue weight between mussels of similar shell length collected from the intertidal and subtidal environments. At the end of the experiment, subtidal individuals had higher gill efficiency, which probably lead to higher total feeding and absorption rates relative to intertidal individuals. PMID:26849372

  16. Inter-Individual Differences in the Initial 80 Minutes of Motor Learning of Handrim Wheelchair Propulsion

    PubMed Central

    Vegter, Riemer J. K.; Lamoth, Claudine J.; de Groot, Sonja; Veeger, Dirkjan H. E. J.; van der Woude, Lucas H. V.

    2014-01-01

    Handrim wheelchair propulsion is a cyclic skill that needs to be learned during rehabilitation. Yet it is unclear how inter-individual differences in motor learning impact wheelchair propulsion practice. Therefore we studied how early-identified motor learning styles in novice able-bodied participants impact the outcome of a low-intensity wheelchair-practice intervention. Over a 12-minute pre-test, 39 participants were split in two groups based on a relative 10% increase in mechanical efficiency. Following the pretest the participants continued one of four different low-intensity wheelchair practice interventions, yet all performed in the same trial-setup with a total 80-minute dose at 1.11 m/s at 0.20 W/kg. Instead of focusing on the effect of the different interventions, we focused on differences in motor learning between participants over the intervention. Twenty-six participants started the pretest with a lower mechanical efficiency and a less optimal propulsion technique, but showed a fast improvement during the first 12 minutes and this effect continued over the 80 minutes of practice. Eventually these initially fast improvers benefitted more from the given practice indicated by a better propulsion technique (like reduced frequency and increased stroke angle) and a higher mechanical efficiency. The initially fast improvers also had a higher intra-individual variability in the pre and posttest, which possibly relates to the increased motor learning of the initially fast improvers. Further exploration of the common characteristics of different types of learners will help to better tailor rehabilitation to the needs of wheelchair-dependent persons and improve our understanding of cyclic motor learning processes. PMID:24586992

  17. Impact of inter-individual differences in drug metabolism and pharmacokinetics on safety evaluation.

    PubMed

    Dorne, J L C M

    2004-12-01

    of up to 45 and 9 would allow for the variability observed in children for CYP2D6 and CYP2C19 metabolism, respectively. This review presents an overview on the history of uncertainty factors, the main conclusions drawn from the analysis of inter-individual differences in metabolism and pharmacokinetics, the development of pathway-related uncertainty factors and their use in chemical risk assessment. PMID:15548231

  18. Inter-individual differences in response to dietary intervention: Integrating omics platforms toward personalised dietary recommendations

    PubMed Central

    Lampe, Johanna W.; Navarro, Sandi L.; Hullar, Meredith A.J.; Shojaie, Ali

    2013-01-01

    Technologic advances now make it possible to collect large amounts of genetic, epigenetic, metabolomic, and gut microbiome data. These data have the potential to transform approaches toward nutrition counseling by allowing us to recognize and embrace the metabolic, physiologic and genetic differences among individuals. The ultimate goal is to be able to integrate these multi-dimensional data so as to characterize the health status and disease risk of an individual and to provide personalised recommendations to maximize health. To this end, accurate and predictive systems-based measures of health are needed that incorporate molecular signatures of genes, transcripts, proteins, metabolites, and microbes. Although we are making progress within each of these omics arenas, we have yet to integrate effectively multiple sources of biologic data so as to provide comprehensive phenotypic profiles. Observational studies have provided some insights into associative interactions between genetic or phenotypic variation and diet and their impact on health; however, few human experimental studies have addressed these relationships. Dietary interventions that test prescribed diets in well-characterized study populations and that monitor system-wide responses (ideally using several omics platforms) are needed to make correlation-causation connections and to characterize phenotypes under controlled conditions. Given the growth in our knowledge, there is the potential to develop personalised dietary recommendations. However, developing these recommendations assumes that an improved understanding of the phenotypic complexities of individuals and their responses to the complexities of their diets will lead to a sustainable, effective approach to promote health and prevent disease — therein lies our challenge. PMID:23388096

  19. Effects of gonadectomy and serotonin depletion on inter-individual differences in anxiety-like behaviour in male Wistar rats.

    PubMed

    Näslund, Jakob; Studer, Erik; Johansson, Elin; Eriksson, Elias

    2016-07-15

    Previous studies in Wistar rats suggest inter-individual differences in anxiety-like behaviour as assessed using the elevated plus maze (EPM), both between sexes and among males, to be abolished by serotonin depletion. To shed further light on the influence of sex steroids and serotonin - and on the interplay between the two - on proneness for EPM-assessed anxiety in males, outbred Wistar rats were divided into those with high and low anxiety, respectively, and exposed to gonadectomy or sham operation followed by administration of a serotonin synthesis inhibitor, para-chlorophenylalanine, or saline. Whereas gonadectomy enhanced anxiety-like behaviour in low anxiety rats so that these no longer differed in this regard from the high anxiety group, serotonin depletion reversed this effect, and also reduced anxiety in the low anxiety group regardless of gonadal state. A previously observed association between high anxiety-like behaviour and high expression of the serotonin-synthesizing enzyme tryptophan hydroxylase 2 (Tph2) in the raphe was confirmed in sham-operated animals but absent in gonadectomised rats, an ANCOVA revealing a significant interactive effect of baseline anxiety and gonadal state on Tph2 expression. It is suggested that androgens may contribute to upholding inter-individual differences in anxiety-like behaviour in male rats by interacting with serotonergic neurotransmission. PMID:27083304

  20. Investigating Inter-Individual Differences in Short-Term Intra-Individual Variability

    ERIC Educational Resources Information Center

    Wang, Lijuan; Hamaker, Ellen; Bergeman, C. S.

    2012-01-01

    Intra-individual variability over a short period of time may contain important information about how individuals differ from each other. In this article we begin by discussing diverse indicators for quantifying intra-individual variability and indicate their advantages and disadvantages. Then we propose an alternative method that models…

  1. The Impact of Disappointment in Decision Making: Inter-Individual Differences and Electrical Neuroimaging

    PubMed Central

    Tzieropoulos, Hélène; de Peralta, Rolando Grave; Bossaerts, Peter; Andino, Sara L. Gonzalez

    2011-01-01

    Disappointment, the emotion experienced when faced to reward prediction errors (RPEs), considerably impacts decision making (DM). Individuals tend to modify their behavior in an often unpredictable way just to avoid experiencing negative emotions. Despite its importance, disappointment remains much less studied than regret and its impact on upcoming decisions largely unexplored. Here, we adapted the Trust Game to effectively elicit, quantify, and isolate disappointment by relying on the formal definition provided by Bell's in economics. We evaluated the effects of experienced disappointment and elation on future cooperation and trust as well as the rationality and utility of the different behavioral and neural mechanisms used to cope with disappointment. All participants in our game trusted less and particularly expected less from unknown opponents as a result of disappointing outcomes in the previous trial but not necessarily after elation indicating that behavioral consequences of positive and negative RPEs are not the same. A large variance in the tolerance to disappointment was observed across subjects, with some participants needing only a small disappointment to impulsively bias their subsequent decisions. As revealed by high-density EEG recordings the most tolerant individuals – who thought twice before making a decision and earned more money – relied on different neural generators to contend with neutral and unexpected outcomes. This study thus provides some support to the idea that different neural systems underlie reflexive and reflective decisions within the same individuals as predicted by the dual-system theory of social judgment and DM. PMID:21258645

  2. Linking inter-individual differences in the perceptual load effect to spontaneous brain activity

    PubMed Central

    Liu, Lu; Tan, Jinfeng; Chen, Antao

    2015-01-01

    Previous researches have widely demonstrated that the interference from peripheral distractor will decrease when the task load is high. However, no study to date has paid attention to the individual differences in perceptual load effect (PLE) and little is known of spontaneous brain activity associated with PLE during resting state. To investigate this issue, we used resting-state functional Magnetic Resonance Imaging (fMRI) to examine the relationship between the amplitude of low-frequency fluctuations (ALFFs) and PLE. The results showed that there were large individual differences in PLE and we found PLE was significantly associated with ALFFs in left inferior temporal gyrus (ITG) and left precentral/postcentral gyrus. The present study suggested that the PLE was measurable, and there were individual differences in this effect. Moreover, these results implicated that: 1) mutual competition for limited capacity, which is involved in visual attention, and 2) response control that is included in behavior response both may contribute to the modulation induced by perceptual load. PMID:26257628

  3. Inter-individual differences in audio-motor learning of piano melodies and white matter fiber tract architecture.

    PubMed

    Engel, Annerose; Hijmans, Brenda S; Cerliani, Leonardo; Bangert, Marc; Nanetti, Luca; Keller, Peter E; Keysers, Christian

    2014-05-01

    Humans vary substantially in their ability to learn new motor skills. Here, we examined inter-individual differences in learning to play the piano, with the goal of identifying relations to structural properties of white matter fiber tracts relevant to audio-motor learning. Non-musicians (n = 18) learned to perform three short melodies on a piano keyboard in a pure audio-motor training condition (vision of their own fingers was occluded). Initial learning times ranged from 17 to 120 min (mean ± SD: 62 ± 29 min). Diffusion-weighted magnetic resonance imaging was used to derive the fractional anisotropy (FA), an index of white matter microstructural arrangement. A correlation analysis revealed that higher FA values were associated with faster learning of piano melodies. These effects were observed in the bilateral corticospinal tracts, bundles of axons relevant for the execution of voluntary movements, and the right superior longitudinal fasciculus, a tract important for audio-motor transformations. These results suggest that the speed with which novel complex audio-motor skills can be acquired may be determined by variability in structural properties of white matter fiber tracts connecting brain areas functionally relevant for audio-motor learning. PMID:23904213

  4. Lymphoblastoid Cell Lines as a Tool to Study Inter-Individual Differences in the Response to Glucose

    PubMed Central

    Grassi, Michael A.; Rao, Vidhya R.; Chen, Siquan; Cao, Dingcai; Gao, Xiaoyu; Cleary, Patricia A.; Huang, R. Stephanie; Paterson, Andrew D.; Natarajan, Rama; Rehman, Jalees; Kern, Timothy S.

    2016-01-01

    Background White blood cells have been shown in animal studies to play a central role in the pathogenesis of diabetic retinopathy. Lymphoblastoid cells are immortalized EBV-transformed primary B-cell leukocytes that have been extensively used as a model for conditions in which white blood cells play a primary role. The purpose of this study was to investigate whether lymphoblastoid cell lines, by retaining many of the key features of primary leukocytes, can be induced with glucose to demonstrate relevant biological responses to those found in diabetic retinopathy. Methods Lymphoblastoid cell lines were obtained from twenty-three human subjects. Differences between high and standard glucose conditions were assessed for expression, endothelial adhesion, and reactive oxygen species. Results Collectively, stimulation of the lymphoblastoid cell lines with high glucose demonstrated corresponding changes on molecular, cellular and functional levels. Lymphoblastoid cell lines up-regulated expression of a panel of genes associated with the leukocyte-mediated inflammation found in diabetic retinopathy that include: a cytokine (IL-1B fold change = 2.11, p-value = 0.02), an enzyme (PKCB fold change = 2.30, p-value = 0.01), transcription factors (NFKB-p50 fold change = 2.05, p-value = 0.01), (NFKB-p65 fold change = 2.82, p-value = 0.003), and an adhesion molecule (CD18 fold change = 2.59, 0.02). Protein expression of CD18 was also increased (p-value = 2.14x10-5). The lymphoblastoid cell lines demonstrated increased adhesiveness to endothelial cells (p = 1.28x10-5). Reactive oxygen species were increased (p = 2.56x10-6). Significant inter-individual variation among the lymphoblastoid cell lines in these responses was evident (F = 18.70, p < 0.0001). Conclusions Exposure of lymphoblastoid cell lines derived from different human subjects to high glucose demonstrated differential and heterogeneous gene expression, adhesion, and cellular effects that recapitulated features found in

  5. The Importance of Encoding-Related Neural Dynamics in the Prediction of Inter-Individual Differences in Verbal Working Memory Performance

    PubMed Central

    Majerus, Steve; Salmon, Eric; Attout, Lucie

    2013-01-01

    Studies of brain-behaviour interactions in the field of working memory (WM) have associated WM success with activation of a fronto-parietal network during the maintenance stage, and this mainly for visuo-spatial WM. Using an inter-individual differences approach, we demonstrate here the equal importance of neural dynamics during the encoding stage, and this in the context of verbal WM tasks which are characterized by encoding phases of long duration and sustained attentional demands. Participants encoded and maintained 5-word lists, half of them containing an unexpected word intended to disturb WM encoding and associated task-related attention processes. We observed that inter-individual differences in WM performance for lists containing disturbing stimuli were related to activation levels in a region previously associated with task-related attentional processing, the left intraparietal sulcus (IPS), and this during stimulus encoding but not maintenance; functional connectivity strength between the left IPS and lateral prefrontal cortex (PFC) further predicted WM performance. This study highlights the critical role, during WM encoding, of neural substrates involved in task-related attentional processes for predicting inter-individual differences in verbal WM performance, and, more generally, provides support for attention-based models of WM. PMID:23874935

  6. Post-Zygotic and Inter-Individual Structural Genetic Variation in a Presumptive Enhancer Element of the Locus between the IL10Rβ and IFNAR1 Genes

    PubMed Central

    Prakash, Kancherla Reddy; Przerada, Szymon; Paprocka, Hanna; Zywicka, Anna; Westerman, Maxwell P.; Pedersen, Nancy L.; O'Hanlon, Terrance P.; Rider, Lisa G.; Miller, Frederick W.; Srutek, Ewa; Jankowski, Michal; Zegarski, Wojciech; Piotrowski, Arkadiusz; Absher, Devin; Dumanski, Jan P.

    2013-01-01

    Although historically considered as junk-DNA, tandemly repeated sequence motifs can affect human phenotype. For example, variable number tandem repeats (VNTR) with embedded enhancers have been shown to regulate gene transcription. The post-zygotic variation is the presence of genetically distinct populations of cells in an individual derived from a single zygote, and this is an understudied aspect of genome biology. We report somatically variable VNTR with sequence properties of an enhancer, located upstream of IFNAR1. Initially, SNP genotyping of 63 monozygotic twin pairs and multiple tissues from 21 breast cancer patients suggested a frequent post-zygotic mosaicism. The VNTR displayed a repeated 32 bp core motif in the center of the repeat, which was flanked by similar variable motifs. A total of 14 alleles were characterized based on combinations of segments, which showed post-zygotic and inter-individual variation, with up to 6 alleles in a single subject. Somatic variation occurred in ∼24% of cases. In this hypervariable region, we found a clustering of transcription factor binding sites with strongest sequence similarity to mouse Foxg1 transcription factor binding motif. This study describes a VNTR with sequence properties of an enhancer that displays post-zygotic and inter-individual genetic variation. This element is within a locus containing four related cytokine receptors: IFNAR2, IL10Rβ, IFNAR1 and IFNGR2, and we hypothesize that it might function in transcriptional regulation of several genes in this cluster. Our findings add another level of complexity to the variation among VNTR-based enhancers. Further work may unveil the normal function of this VNTR in transcriptional control and its possible involvement in diseases connected with these receptors, such as autoimmune conditions and cancer. PMID:24023707

  7. Inter-individual differences in breathing pattern at high levels of incremental cycling exercise in healthy subjects.

    PubMed

    Gravier, Gilles; Delliaux, Stephane; Delpierre, Stephane; Guieu, Regis; Jammes, Yves

    2013-10-01

    Interindividual differences in the rate of changes in tidal volume (V(T)) and respiratory frequency (f(R)) were examined during a maximal incremental cycling exercise. The gain of the inspiratory off-switch reflex was inferred from the V(T) vs. inspiratory duration (T(i)) relationship. Some subjects also executed a static handgrip exercise, used as a "non-dynamic" exercise trial to study patterning of breathing. Above the ventilatory threshold (V(Th)), two patterns of response were identified: in group 1, the rate of change in V(T) significantly increased, while in group 2 the breakpoint of ventilation solely resulted from f(R) increase. After the respiratory compensation point, a tachypnoeic response always occurred. A leftward shift of the V(T) vs. Ti relationship, i.e., an inspiratory off-switch reflex, was measured during the handgrip in group 2 subjects as well as marked f(R) variations. Our study identifies two different patterns of breathing after the V(Th). The subjects who present a tachypnoeic response to exercise above the V(Th) have a higher sensitivity to pulmonary inflation and their tachypnoeic response was ubiquitous during a maximal handgrip test. PMID:23832014

  8. Inter-individual variation in fronto-temporal connectivity predicts the ability to learn different types of associations.

    PubMed

    Alm, Kylie H; Rolheiser, Tyler; Olson, Ingrid R

    2016-05-15

    The uncinate fasciculus connects portions of the anterior and medial temporal lobes to the lateral orbitofrontal cortex, so it has long been thought that this limbic fiber pathway plays an important role in episodic memory. Some types of episodic memory are impaired after damage to the uncinate, while others remain intact. Because of this, the specific role played by the uncinate fasciculus in episodic memory remains undetermined. In the present study, we tested the hypothesis that the uncinate fasciculus is involved in episodic memory tasks that have high competition between representations at retrieval. To test this hypothesis, healthy young adults performed three tasks: Experiment 1 in which they learned to associate names with faces through feedback provided at the end of each trial; Experiment 2 in which they learned to associate fractals with cued locations through feedback provided at the end of each trial; and Experiment 3 in which unique faces were remembered in a paradigm with low retrieval competition. Diffusion tensor imaging and deterministic tractography methods were used to extract measures of uncinate fasciculus microstructure. Results revealed that microstructural properties of the uncinate, but not a control tract, the inferior longitudinal fasciculus, significantly predicted individual differences in performance on the face-name and fractal-location tasks. However, no relationship was observed for simple face memory (Experiment 3). These findings suggest that the uncinate fasciculus may be important for adjudicating between competing memory representations at the time of episodic retrieval. PMID:26908315

  9. Inter-Individual Differences in the Oral Bacteriome Are Greater than Intra-Day Fluctuations in Individuals

    PubMed Central

    Shinozaki, Natsuko; Ye, Bin; Yamada, Takuji; Yamamoto, Masayuki; Nagasaki, Masao; Tsuboi, Akito

    2015-01-01

    Given the advent of massively parallel DNA sequencing, human microbiome is analyzed comprehensively by metagenomic approaches. However, the inter- and intra-individual variability and stability of the human microbiome remain poorly characterized, particularly at the intra-day level. This issue is of crucial importance for studies examining the effects of microbiome on human health. Here, we focused on bacteriome of oral plaques, for which repeated, time-controlled sampling is feasible. Eighty-one supragingival plaque subjects were collected from healthy individuals, examining multiple sites within the mouth at three time points (forenoon, evening, and night) over the course of 3 days. Bacterial composition was estimated by 16S rRNA sequencing and species-level profiling, resulting in identification of a total of 162 known bacterial species. We found that species compositions and their relative abundances were similar within individuals, and not between sampling time or tooth type. This suggests that species-level oral bacterial composition differs significantly between individuals, although the number of subjects is limited and the intra-individual variation also occurs. The majority of detected bacterial species (98.2%; 159/162), however, did not fluctuate over the course of the day, implying a largely stable oral microbiome on an intra-day time scale. In fact, the stability of this data set enabled us to estimate potential interactions between rare bacteria, with 40 co-occurrences supported by the existing literature. In summary, the present study provides a valuable basis for studies of the human microbiome, with significant implications in terms of biological and clinical outcomes. PMID:26121551

  10. Consistent inter-individual differences in common marmosets (Callithrix jacchus) in Boldness-Shyness, Stress-Activity, and Exploration-Avoidance.

    PubMed

    Šlipogor, Vedrana; Gunhold-de Oliveira, Tina; Tadić, Zoran; Massen, Jorg J M; Bugnyar, Thomas

    2016-09-01

    The study of animal personality, defined as consistent inter-individual differences in correlated behavioral traits stable throughout time and/or contexts, has recently become one of the fastest growing areas in animal biology, with study species ranging from insects to non-human primates. The latter have, however, only occasionally been tested with standardized experiments. Instead their personality has usually been assessed using questionnaires. Therefore, this study aimed to test 21 common marmosets (Callithrix jacchus) living in three family groups, in five different experiments, and their corresponding controls. We found that behavioral differences between our animals were not only consistent over time, but also across different contexts. Moreover, the consistent behaviors formed a construct of four major non-social personality components: Boldness-Shyness in Foraging, Boldness-Shyness in Predation, Stress-Activity, and Exploration-Avoidance. We found no sex or age differences in these components, but our results did reveal differences in Exploration-Avoidance between the three family groups. As social environment can have a large influence on behavior of individuals, our results may suggest group-level similarity in personality (i.e., "group personality") in common marmosets, a species living in highly cohesive social groups. Am. J. Primatol. 78:961-973, 2016. © 2016 Wiley Periodicals, Inc. PMID:27286098

  11. Reliability of cut mark analysis in human costal cartilage: the effects of blade penetration angle and intra- and inter-individual differences.

    PubMed

    Puentes, K; Cardoso, H F V

    2013-09-10

    Identification of tool class characteristics from cut marks in either bone or cartilage is a valuable source of data for the forensic scientist. Various animal models have been used in experimental studies for the analysis of individual and class characteristics. However, human tissue has seldom been used and it is likely to differ from that of non-humans in key aspects. This study wishes to assess how the knife's blade angle, and both intra- and inter-individual variation in cartilage samples affect the ability of costal cartilage to retain the original class characteristics of the knife, as measured microscopically by the distance between consecutive striations. The 120 cartilaginous samples used in this study originated from the ribcage of 6 male cadavers which were submitted to autopsy at the North Branch of the National Institute of Legal Medicine, in Portugal. Three different serrated knives were purchased from a large department store, and were used in the experimental cuts. Samples of costal cartilage from 2 individuals were assigned to each knife. Each individual provided 20 cartilage samples. Cartilage samples were manually cut using each of the three knives, following two motions: one straight up-and-down cutting motion and parallel and one perpendicular to the blade's teeth long axis forward cutting motion. Casts of the samples were made with Mikrosil(®). Image capture and processing were performed with an Olympus stereomicroscope and its software. The blade's penetration angle and inter-individual variation were shown to affect the identification of the tool class characteristics from the striation pattern observed in a kerf wall, although this seems to be related only to the degree of calcification of the costal cartilage. Intra-individual variation does not seem to significantly affect the identification of the tool class characteristics from the striation pattern observed in a kerf wall, for the same knife following the same motion. Although this

  12. Numerical Transcoding Proficiency in 10-Year-Old Schoolchildren is Associated with Gray Matter Inter-Individual Differences: A Voxel-Based Morphometry Study

    PubMed Central

    Lubin, Amélie; Rossi, Sandrine; Simon, Grégory; Lanoë, Céline; Leroux, Gaëlle; Poirel, Nicolas; Pineau, Arlette; Houdé, Olivier

    2013-01-01

    Are individual differences in numerical performance sustained by variations in gray matter volume in schoolchildren? To our knowledge, this challenging question for neuroeducation has not yet been investigated in typical development. We used the Voxel-Based Morphometry method to search for possible structural brain differences between two groups of 10-year-old schoolchildren (N = 22) whose performance differed only in numerical transcoding between analog and symbolic systems. The results indicated that children with low numerical proficiency have less gray matter volume in the parietal (particularly in the left intraparietal sulcus and the bilateral angular gyri) and occipito-temporal areas. All the identified regions have previously been shown to be functionally involved in transcoding between analog and symbolic numerical systems. Our data contribute to a better understanding of the intertwined relationships between mathematics learning and brain structure in healthy schoolchildren. PMID:23630510

  13. Numerical Transcoding Proficiency in 10-Year-Old Schoolchildren is Associated with Gray Matter Inter-Individual Differences: A Voxel-Based Morphometry Study.

    PubMed

    Lubin, Amélie; Rossi, Sandrine; Simon, Grégory; Lanoë, Céline; Leroux, Gaëlle; Poirel, Nicolas; Pineau, Arlette; Houdé, Olivier

    2013-01-01

    Are individual differences in numerical performance sustained by variations in gray matter volume in schoolchildren? To our knowledge, this challenging question for neuroeducation has not yet been investigated in typical development. We used the Voxel-Based Morphometry method to search for possible structural brain differences between two groups of 10-year-old schoolchildren (N = 22) whose performance differed only in numerical transcoding between analog and symbolic systems. The results indicated that children with low numerical proficiency have less gray matter volume in the parietal (particularly in the left intraparietal sulcus and the bilateral angular gyri) and occipito-temporal areas. All the identified regions have previously been shown to be functionally involved in transcoding between analog and symbolic numerical systems. Our data contribute to a better understanding of the intertwined relationships between mathematics learning and brain structure in healthy schoolchildren. PMID:23630510

  14. Inter-individual differences in successful perspective taking during pain perception mediates emotional responsiveness in self and others: an fMRI study.

    PubMed

    van der Heiden, Linda; Scherpiet, Sigrid; Konicar, Lilian; Birbaumer, Niels; Veit, Ralf

    2013-01-15

    Human empathy is an important component of social cognition that involves complex processes of emotional perspective taking and the issue of self/other distinction. Empathic perception enables us to experience negative emotions when someone else undergoes painful events. We investigated the influence of an extended time interval (10s) and subjective performance evaluation (following each trial) of perspective taking on the cortical and subcortical correlates of pain empathy in eighteen healthy subjects using functional magnetic resonance imaging (fMRI). Subjects were presented pictures of hands and feet in painful and non-painful situations. They were instructed to simply view the picture (View) or adopt either their own perspective (Self) or the perspective of a third-person (Other). Prolonged time intervals of stimulus presentation enabled the analysis of different perspective taking processes (Self versus Other). Enhanced activation in the left supramarginal gyrus was detected for adopting the Self compared to the Other perspective. Time course analysis showed an early peak in the trials, suggesting that taking the first-person perspective is an intuitive more automatic process. The comparison between the Other and Self condition evoked stronger activity in dorso- and ventrolateral prefrontal areas and the superior temporal sulcus (STS). For these areas, a peak in the later phase of the trials was found, suggesting that taking the third-person perspective requires more effort and is an ongoing process. This was also supported by the fact that the participants were subjectively more successful in adopting the Self perspective compared to the Other. Our findings support that especially during the Other condition, prolonged time periods seem to facilitate empathic responses. Individual ratings of performance enabled the comparison between subjects that were successful and unsuccessful at taking the Self or Other perspective. For Self, differential activations were

  15. Inter-individual differences in CpG methylation at D4Z4 correlate with clinical variability in FSHD1 and FSHD2

    PubMed Central

    Lemmers, Richard J.L.F.; Goeman, Jelle J.; van der Vliet, Patrick J.; van Nieuwenhuizen, Merlijn P.; Balog, Judit; Vos-Versteeg, Marianne; Camano, Pilar; Ramos Arroyo, Maria Antonia; Jerico, Ivonne; Rogers, Mark T.; Miller, Daniel G.; Upadhyaya, Meena; Verschuuren, Jan J.G.M.; Lopez de Munain Arregui, Adolfo; van Engelen, Baziel G.M.; Padberg, George W.; Sacconi, Sabrina; Tawil, Rabi; Tapscott, Stephen J.; Bakker, Bert; van der Maarel, Silvère M.

    2015-01-01

    Facioscapulohumeral muscular dystrophy (FSHD: MIM#158900) is a common myopathy with marked but largely unexplained clinical inter- and intra-familial variability. It is caused by contractions of the D4Z4 repeat array on chromosome 4 to 1–10 units (FSHD1), or by mutations in the D4Z4-binding chromatin modifier SMCHD1 (FSHD2). Both situations lead to a partial opening of the D4Z4 chromatin structure and transcription of D4Z4-encoded polyadenylated DUX4 mRNA in muscle. We measured D4Z4 CpG methylation in control, FSHD1 and FSHD2 individuals and found a significant correlation with the D4Z4 repeat array size. After correction for repeat array size, we show that the variability in clinical severity in FSHD1 and FSHD2 individuals is dependent on individual differences in susceptibility to D4Z4 hypomethylation. In FSHD1, for individuals with D4Z4 repeat arrays of 1–6 units, the clinical severity mainly depends on the size of the D4Z4 repeat. However, in individuals with arrays of 7–10 units, the clinical severity also depends on other factors that regulate D4Z4 methylation because affected individuals, but not non-penetrant mutation carriers, have a greater reduction of D4Z4 CpG methylation than can be expected based on the size of the pathogenic D4Z4 repeat array. In FSHD2, this epigenetic susceptibility depends on the nature of the SMCHD1 mutation in combination with D4Z4 repeat array size with dominant negative mutations being more deleterious than haploinsufficiency mutations. Our study thus identifies an epigenetic basis for the striking variability in onset and disease progression that is considered a clinical hallmark of FSHD. PMID:25256356

  16. Inter-individual differences in CpG methylation at D4Z4 correlate with clinical variability in FSHD1 and FSHD2.

    PubMed

    Lemmers, Richard J L F; Goeman, Jelle J; van der Vliet, Patrick J; van Nieuwenhuizen, Merlijn P; Balog, Judit; Vos-Versteeg, Marianne; Camano, Pilar; Ramos Arroyo, Maria Antonia; Jerico, Ivonne; Rogers, Mark T; Miller, Daniel G; Upadhyaya, Meena; Verschuuren, Jan J G M; Lopez de Munain Arregui, Adolfo; van Engelen, Baziel G M; Padberg, George W; Sacconi, Sabrina; Tawil, Rabi; Tapscott, Stephen J; Bakker, Bert; van der Maarel, Silvère M

    2015-02-01

    Facioscapulohumeral muscular dystrophy (FSHD: MIM#158900) is a common myopathy with marked but largely unexplained clinical inter- and intra-familial variability. It is caused by contractions of the D4Z4 repeat array on chromosome 4 to 1-10 units (FSHD1), or by mutations in the D4Z4-binding chromatin modifier SMCHD1 (FSHD2). Both situations lead to a partial opening of the D4Z4 chromatin structure and transcription of D4Z4-encoded polyadenylated DUX4 mRNA in muscle. We measured D4Z4 CpG methylation in control, FSHD1 and FSHD2 individuals and found a significant correlation with the D4Z4 repeat array size. After correction for repeat array size, we show that the variability in clinical severity in FSHD1 and FSHD2 individuals is dependent on individual differences in susceptibility to D4Z4 hypomethylation. In FSHD1, for individuals with D4Z4 repeat arrays of 1-6 units, the clinical severity mainly depends on the size of the D4Z4 repeat. However, in individuals with arrays of 7-10 units, the clinical severity also depends on other factors that regulate D4Z4 methylation because affected individuals, but not non-penetrant mutation carriers, have a greater reduction of D4Z4 CpG methylation than can be expected based on the size of the pathogenic D4Z4 repeat array. In FSHD2, this epigenetic susceptibility depends on the nature of the SMCHD1 mutation in combination with D4Z4 repeat array size with dominant negative mutations being more deleterious than haploinsufficiency mutations. Our study thus identifies an epigenetic basis for the striking variability in onset and disease progression that is considered a clinical hallmark of FSHD. PMID:25256356

  17. Inter-individual cognitive variability in children with Asperger's syndrome

    PubMed Central

    Gonzalez-Gadea, Maria Luz; Tripicchio, Paula; Rattazzi, Alexia; Baez, Sandra; Marino, Julian; Roca, Maria; Manes, Facundo; Ibanez, Agustin

    2014-01-01

    Multiple studies have tried to establish the distinctive profile of individuals with Asperger's syndrome (AS). However, recent reports suggest that adults with AS feature heterogeneous cognitive profiles. The present study explores inter-individual variability in children with AS through group comparison and multiple case series analysis. All participants completed an extended battery including measures of fluid and crystallized intelligence, executive functions, theory of mind, and classical neuropsychological tests. Significant group differences were found in theory of mind and other domains related to global information processing. However, the AS group showed high inter-individual variability (both sub- and supra-normal performance) on most cognitive tasks. Furthermore, high fluid intelligence correlated with less general cognitive impairment, high cognitive flexibility, and speed of motor processing. In light of these findings, we propose that children with AS are characterized by a distinct, uneven pattern of cognitive strengths and weaknesses. PMID:25132817

  18. Inter-individual cognitive variability in children with Asperger's syndrome.

    PubMed

    Gonzalez-Gadea, Maria Luz; Tripicchio, Paula; Rattazzi, Alexia; Baez, Sandra; Marino, Julian; Roca, Maria; Manes, Facundo; Ibanez, Agustin

    2014-01-01

    Multiple studies have tried to establish the distinctive profile of individuals with Asperger's syndrome (AS). However, recent reports suggest that adults with AS feature heterogeneous cognitive profiles. The present study explores inter-individual variability in children with AS through group comparison and multiple case series analysis. All participants completed an extended battery including measures of fluid and crystallized intelligence, executive functions, theory of mind, and classical neuropsychological tests. Significant group differences were found in theory of mind and other domains related to global information processing. However, the AS group showed high inter-individual variability (both sub- and supra-normal performance) on most cognitive tasks. Furthermore, high fluid intelligence correlated with less general cognitive impairment, high cognitive flexibility, and speed of motor processing. In light of these findings, we propose that children with AS are characterized by a distinct, uneven pattern of cognitive strengths and weaknesses. PMID:25132817

  19. Genetic Differences in Intelligence

    ERIC Educational Resources Information Center

    Intellect, 1977

    1977-01-01

    The Genetics Society of America has released a statement saying that the possibility of a "genetic difference in intelligence between races" is still an open question and warning against "the misuse of genetics for political purposes". (Editor)

  20. Inter-individual stereotypy of the Platynereis larval visual connectome

    PubMed Central

    Randel, Nadine; Shahidi, Réza; Verasztó, Csaba; Bezares-Calderón, Luis A; Schmidt, Steffen; Jékely, Gáspár

    2015-01-01

    Developmental programs have the fidelity to form neural circuits with the same structure and function among individuals of the same species. It is less well understood, however, to what extent entire neural circuits of different individuals are similar. Previously, we reported the neuronal connectome of the visual eye circuit from the head of a Platynereis dumerilii larva (Randel et al., 2014). We now report a full-body serial section transmission electron microscopy (ssTEM) dataset of another larva of the same age, for which we describe the connectome of the visual eyes and the larval eyespots. Anatomical comparisons and quantitative analyses of the two circuits reveal a high inter-individual stereotypy of the cell complement, neuronal projections, and synaptic connectivity, including the left-right asymmetry in the connectivity of some neurons. Our work shows the extent to which the eye circuitry in Platynereis larvae is hard-wired. DOI: http://dx.doi.org/10.7554/eLife.08069.001 PMID:26061864

  1. The genetic difference principle.

    PubMed

    Farrelly, Colin

    2004-01-01

    In the newly emerging debates about genetics and justice three distinct principles have begun to emerge concerning what the distributive aim of genetic interventions should be. These principles are: genetic equality, a genetic decent minimum, and the genetic difference principle. In this paper, I examine the rationale of each of these principles and argue that genetic equality and a genetic decent minimum are ill-equipped to tackle what I call the currency problem and the problem of weight. The genetic difference principle is the most promising of the three principles and I develop this principle so that it takes seriously the concerns of just health care and distributive justice in general. Given the strains on public funds for other important social programmes, the costs of pursuing genetic interventions and the nature of genetic interventions, I conclude that a more lax interpretation of the genetic difference principle is appropriate. This interpretation stipulates that genetic inequalities should be arranged so that they are to the greatest reasonable benefit of the least advantaged. Such a proposal is consistent with prioritarianism and provides some practical guidance for non-ideal societies--that is, societies that do not have the endless amount of resources needed to satisfy every requirement of justice. PMID:15186680

  2. Inter-individual variation in midazolam clearance in children

    PubMed Central

    Altamimi, Mohammed I; Sammons, Helen; Choonara, Imti

    2015-01-01

    Objectives To determine the extent of inter-individual variation in clearance of midazolam in children and establish which factors are responsible for this variation. Methods A systematic literature review was performed to identify papers describing the clearance of midazolam in children. The following databases were searched: Medline, Embase, International Pharmaceutical Abstracts, CINAHL and Cochrane Library. From the papers, the range in plasma clearance and the coefficient of variation (CV) in plasma clearance were determined. Results 25 articles were identified. Only 13 studies gave the full range of clearance values for individual patients. The CV was greater in critically ill patients (18%–170%) than non-critically ill patients (13%–54%). Inter-individual variation was a major problem in all age groups of critically ill patients. The CV was 72%–106% in preterm neonates, 18%–73% in term neonates, 31%–130% in infants, 21%–170% in children and 47%–150% in adolescents. The mean clearance was higher in children (1.1–16.7 mL/min/kg) than in neonates (0.78–2.5 mL/min/kg). Conclusions Large inter-individual variation was seen in midazolam clearance values in critically ill neonates, infants, children and adolescents. PMID:25281734

  3. Generalisation within specialization: inter-individual diet variation in the only specialized salamander in the world

    PubMed Central

    Costa, Andrea; Salvidio, Sebastiano; Posillico, Mario; Matteucci, Giorgio; De Cinti, Bruno; Romano, Antonio

    2015-01-01

    Specialization is typically inferred at population and species level but in the last decade many authors highlighted this trait at the individual level, finding that generalist populations can be composed by both generalist and specialist individual. Despite hundreds of reported cases of individual specialization there is a complete lack of information on inter-individual diet variation in specialist species. We studied the diet of the Italian endemic Spectacled Salamander (Salamandrina perspicillata), in a temperate forest ecosystem, to disclose the realised trophic niche, prey selection strategy in function of phenotypic variation and inter-individual diet variation. Our results showed that Salamandrina is highly specialized on Collembola and the more specialized individuals are the better performing ones. Analyses of inter-individual diet variation showed that a subset of animals exhibited a broader trophic niche, adopting different foraging strategies. Our findings reflects the optimal foraging theory both at population and individual level, since animals in better physiological conditions are able to exploit the most profitable prey, suggesting that the two coexisting strategies are not equivalent. At last this species, feeding on decomposers of litter detritus, could play a key role determining litter retention rate, nutrient cycle and carbon sequestration. PMID:26292804

  4. Characterizing tropical tree species growth strategies: learning from inter-individual variability and scale invariance.

    PubMed

    Le Bec, Jimmy; Courbaud, Benoit; Le Moguédec, Gilles; Pélissier, Raphaël

    2015-01-01

    Understanding how tropical tree species differ in their growth strategies is critical to predict forest dynamics and assess species coexistence. Although tree growth is highly variable in tropical forests, species maximum growth is often considered as a major axis synthesizing species strategies, with fast-growing pioneer and slow-growing shade tolerant species as emblematic representatives. We used a hierarchical linear mixed model and 21-years long tree diameter increment series in a monsoon forest of the Western Ghats, India, to characterize species growth strategies and question whether maximum growth summarizes these strategies. We quantified both species responses to biotic and abiotic factors and individual tree effects unexplained by these factors. Growth responses to competition and tree size appeared highly variable among species which led to reversals in performance ranking along those two gradients. However, species-specific responses largely overlapped due to large unexplained variability resulting mostly from inter-individual growth differences consistent over time. On average one-third of the variability captured by our model was explained by covariates. This emphasizes the high dimensionality of the tree growth process, i.e. the fact that trees differ in many dimensions (genetics, life history) influencing their growth response to environmental gradients, some being unmeasured or unmeasurable. In addition, intraspecific variability increased as a power function of species maximum growth partly as a result of higher absolute responses of fast-growing species to competition and tree size. However, covariates explained on average the same proportion of intraspecific variability for slow- and fast-growing species, which showed the same range of relative responses to competition and tree size. These results reflect a scale invariance of the growth process, underlining that slow- and fast-growing species exhibit the same range of growth strategies. PMID

  5. Characterizing Tropical Tree Species Growth Strategies: Learning from Inter-Individual Variability and Scale Invariance

    PubMed Central

    Le Bec, Jimmy; Courbaud, Benoit; Le Moguédec, Gilles; Pélissier, Raphaël

    2015-01-01

    Understanding how tropical tree species differ in their growth strategies is critical to predict forest dynamics and assess species coexistence. Although tree growth is highly variable in tropical forests, species maximum growth is often considered as a major axis synthesizing species strategies, with fast-growing pioneer and slow-growing shade tolerant species as emblematic representatives. We used a hierarchical linear mixed model and 21-years long tree diameter increment series in a monsoon forest of the Western Ghats, India, to characterize species growth strategies and question whether maximum growth summarizes these strategies. We quantified both species responses to biotic and abiotic factors and individual tree effects unexplained by these factors. Growth responses to competition and tree size appeared highly variable among species which led to reversals in performance ranking along those two gradients. However, species-specific responses largely overlapped due to large unexplained variability resulting mostly from inter-individual growth differences consistent over time. On average one-third of the variability captured by our model was explained by covariates. This emphasizes the high dimensionality of the tree growth process, i.e. the fact that trees differ in many dimensions (genetics, life history) influencing their growth response to environmental gradients, some being unmeasured or unmeasurable. In addition, intraspecific variability increased as a power function of species maximum growth partly as a result of higher absolute responses of fast-growing species to competition and tree size. However, covariates explained on average the same proportion of intraspecific variability for slow- and fast-growing species, which showed the same range of relative responses to competition and tree size. These results reflect a scale invariance of the growth process, underlining that slow- and fast-growing species exhibit the same range of growth strategies. PMID

  6. Inter-individual susceptibility to environmental toxicants-A current assessment

    SciTech Connect

    Nebert, Daniel W. . E-mail: dan.nebert@uc.edu

    2005-09-01

    Virtually all diseases have an environmental component. The two most important factors affecting your unique risk of an environmental disease (toxicity or cancer) are (a) your exposure to the environmental agent and (b) your genes. Epidemiologists have found ways to calculate inter-individual risk-if the exposure to environmental agents is sufficiently high and can be documented (e.g., years of cigarette smoking, taking prescribed drugs, drinking alcohol, or exposure to radon or other radioactive material, etc.). If the dose of environmental agents is lower and more ambiguous (e.g., exposure to chemicals on the job, herbicides sprayed on a golf course, outdoor or indoor air pollution, endocrine disruptors in cans of food, living near a toxic waste dump site, etc.), however, calculations of inter-individual risk become much more difficult. Highly accurate DNA tests for genetic susceptibility to toxicity and cancer have been sought in order to identify individuals at increased risk; this type of research represents the leading edge of phenotype-genotype association studies and is the major goal of most public health and preventive medicine programs. The task, however, has turned out to be far more challenging than anticipated. The major stumbling block has been the difficulty in determining an unequivocal phenotype or an unequivocal genotype. We were quite optimistic 5-10 years ago that this would be easy, but now we are beginning to appreciate how difficult it is to determine an unequivocal phenotype or genotype with certainty. For many reasons set forth in this overview, it appears that DNA testing alone, to predict and prevent environmental disease on an individual basis, may be virtually impossible with current knowledge and technologies and will require novel insights before major practical applications will evolve.

  7. Inter-Individual Variability and Conspecific Densities: Consequences for Population Regulation and Range Expansion

    PubMed Central

    Cardador, Laura; Carrete, Martina; Mañosa, Santi

    2012-01-01

    The presence of conspecifics can strongly modulate the quality of a breeding site. Both positive and negative effects of conspecifics can act on the same individuals, with the final balance between its costs and benefits depending on individual characteristics. A particular case of inter-individual variation found in many avian species is chromatic variability. Among birds, plumage coloration can co-vary with morphology, physiology and behavior as well as with age. These relationships suggest that cost-benefit balances of conspecific presence may be different for individuals with different colorations. We investigated whether inter-individual variability affects population regulation and expansion processes by analyzing potential differences in density-dependent productivity and settlement patterns in relation to plumage coloration in a population of a long-lived avian species recently undergoing a notable increase in numbers and distribution range. Our results show strong variation in the effect of density on productivity of breeding pairs depending on plumage coloration of their members. Productivity of dark birds decreased along the breeding density gradient while that of lighter breeders remained unchanged with conspecific density. In a similar way, our results showed an uneven occupation of localities by individuals with different plumage coloration in relation to local densities, with the breeding of lighter harriers more aggregated than that of dark-brown ones. At a population scale, darker birds had higher probability of colonization of the most isolated, empty sites. Explanations for species range expansion and population regulation usually make the inferred assumption that species traits are similar among individuals. However, in most species, there could be individual variation in niche requirements or dispersal propensities among individuals with different traits. Our results contribute to the growing appreciation that the individual traits, but not the

  8. Human inter-individual variability in metabolism and genotoxic response to zidovudine

    SciTech Connect

    Olivero, Ofelia A. Ming, Jessica M.; Das, Shreyasi; Vazquez, Irma L.; Richardson, Diana L.; Weston, Ainsley; Poirier, Miriam C.

    2008-04-15

    A mainstay of the antiretroviral drugs used for therapy of HIV-1, zidovudine (AZT) is genotoxic and becomes incorporated into DNA. Here we explored host inter-individual variability in AZT-DNA incorporation, by AZT radioimmunoassay (RIA), using 19 different strains of normal human mammary epithelial cells (NHMECs) exposed for 24 h to 200 {mu}M AZT. Twelve of the 19 NHMEC strains showed detectable AZT-DNA incorporation levels (16 to 259 molecules of AZT/10{sup 6} nucleotides), while 7 NHMEC strains did not show detectable AZT-DNA incorporation. In order to explore the basis for this variability, we compared the 2 NHMEC strains that showed the highest levels of AZT-DNA incorporation (H1 and H2) with 2 strains showing no detectable AZT-DNA incorporation (L1 and L2). All 4 strains had similar ({>=} 80%) cell survival, low levels of accumulation of cells in S-phase, and no relevant differences in response to the direct-acting mutagen bleomycin (BLM). Finally, when levels of thymidine kinase 1 (TK1), the first enzyme in the pathway for incorporation of AZT into DNA, were determined by Western blot analysis in all 19 NHMEC strains at 24 h of AZT exposure, higher TK1 protein levels were found in the 12 strains showing AZT-DNA incorporation, compared to the 7 showing no incorporation (p = 0.0005, Mann-Whitney test). Furthermore, strains L1 and L2, which did not show AZT-DNA incorporation at 24 h, did have measurable incorporation by 48 and 72 h. These data suggest that variability in AZT-DNA incorporation may be modulated by inter-individual differences in the rate of induction of TK1 in response to AZT exposure.

  9. Genetic Differences and School Readiness

    ERIC Educational Resources Information Center

    Dickens, William T.

    2005-01-01

    The author considers whether differences in genetic endowment may account for racial and ethnic differences in school readiness. While acknowledging an important role for genes in explaining differences "within" races, he nevertheless argues that environment explains most of the gap "between" blacks and whites, leaving little role for genetics.…

  10. How Plantar Exteroceptive Efficiency Modulates Postural and Oculomotor Control: Inter-Individual Variability

    PubMed Central

    Foisy, Arnaud; Kapoula, Zoï

    2016-01-01

    In a previous experiment, we showed that among young and healthy subjects, thin plantar inserts improve postural control and modify vergence amplitudes. In this experiment, however, significant inter-individual variability was observed. We hypothesize that its origin could be attributed to a different reliance upon feet cutaneous afferents. In order to test this hypothesis, we re-analyzed the data relative to 31 young (age 25.7 ± 3.8) and healthy subjects who participated in the first experiment after having classified them into two groups depending on their Plantar Quotient (PQ = Surface area of CoPfoam/Surface area of CoPfirm ground × 100). Foam decreases the information arising from the feet, normally resulting in a PQ > 100. Hence, the PQ provides information on the weight of plantar cutaneous afferents used in postural control. Twelve people were Plantar-Independent Subjects, as indicated by a PQ < 100. These individuals did not behave like the Normal Plantar Quotient Subjects: they were almost insensitive to the plantar stimulations in terms of postural control and totally insensitive in terms of oculomotor control. We conclude that the inter-individual variability observed in our first experiment is explained by the subjects' degree of plantar reliance. We propose that plantar independence is a dysfunctional situation revealing inefficiency in plantar cutaneous afferents. The latter could be due to a latent somatosensory dysfunction generating a noise which prevents the CNS from correctly processing and using feet somatosensory afferents both for balance and vergence control: Plantar Irritating Stimulus. Considering the non-noxious nature and prevalence of this phenomenon, these results can be of great interest to researchers and clinicians who attempt to trigger postural or oculomotor responses through mechanical stimulation of the foot sole. PMID:27242490

  11. How Plantar Exteroceptive Efficiency Modulates Postural and Oculomotor Control: Inter-Individual Variability.

    PubMed

    Foisy, Arnaud; Kapoula, Zoï

    2016-01-01

    In a previous experiment, we showed that among young and healthy subjects, thin plantar inserts improve postural control and modify vergence amplitudes. In this experiment, however, significant inter-individual variability was observed. We hypothesize that its origin could be attributed to a different reliance upon feet cutaneous afferents. In order to test this hypothesis, we re-analyzed the data relative to 31 young (age 25.7 ± 3.8) and healthy subjects who participated in the first experiment after having classified them into two groups depending on their Plantar Quotient (PQ = Surface area of CoPfoam/Surface area of CoPfirm ground × 100). Foam decreases the information arising from the feet, normally resulting in a PQ > 100. Hence, the PQ provides information on the weight of plantar cutaneous afferents used in postural control. Twelve people were Plantar-Independent Subjects, as indicated by a PQ < 100. These individuals did not behave like the Normal Plantar Quotient Subjects: they were almost insensitive to the plantar stimulations in terms of postural control and totally insensitive in terms of oculomotor control. We conclude that the inter-individual variability observed in our first experiment is explained by the subjects' degree of plantar reliance. We propose that plantar independence is a dysfunctional situation revealing inefficiency in plantar cutaneous afferents. The latter could be due to a latent somatosensory dysfunction generating a noise which prevents the CNS from correctly processing and using feet somatosensory afferents both for balance and vergence control: Plantar Irritating Stimulus. Considering the non-noxious nature and prevalence of this phenomenon, these results can be of great interest to researchers and clinicians who attempt to trigger postural or oculomotor responses through mechanical stimulation of the foot sole. PMID:27242490

  12. Children’s Inter-Individual Variability and Asthma Development

    PubMed Central

    Saadeh, Rami; Klaunig, James

    2015-01-01

    Children of different ages vary in their response to environmental stressors due to their continuous development and changes in their bodies’ anatomy, physiology, and biochemistry. Each age group of children has special biological features that distinguish their toxicokinetic and toxicodynamic characteristics from other age groups. The variability in responses extends to include children of the same age group. These intra- and inter-group differences in biological features explains the variability in responses to environmental exposures. Based on such differences in children’s responses to exposures, adverse health outcomes and diseases develop differently in children. One of these diseases that are common in children is asthma. Asthma is a complex respiratory chronic disease that is multifactorial in origin. This paper discusses how variability in certain factors among children contributes to asthma occurrence or exacerbation, and links these factors to asthma in children of different ages. The importance of this review is to provide an insight on factors affecting asthma prevalence among children. These factors are usually overlooked in clinical or public health practice, which might significantly affect asthma management, and decrease the predictability of asthma detection measures. Therefore, keeping these factors into consideration can significantly improve asthma treatment and assist in asthma prevention amongst susceptible populations. PMID:26715926

  13. Can Dental Microwear Textures Record Inter-Individual Dietary Variations?

    PubMed Central

    Merceron, Gildas; Escarguel, Gilles; Angibault, Jean-Marc; Verheyden-Tixier, Hélène

    2010-01-01

    Background Dental microwear analyses are commonly used to deduce the diet of extinct mammals. Conventional methods rely on the user identifying features within a 2D image. However, recent interdisciplinary research has lead to the development of an advanced methodology that is free of observer error, based on the automated quantification of 3D surfaces by combining confocal microscopy with scale-sensitive fractal analysis. This method has already proved to be very efficient in detecting dietary differences between species. Focusing on a finer, intra-specific scale of analysis, the aim of this study is to test this method's ability to track such differences between individuals from a single population. Methodology/Principal Findings For the purposes of this study, the 3D molar microwear of 78 individuals from a well-known population of extant roe deer (Capreolus caprelous) is quantified. Multivariate statistical analyses indicate significant seasonal and sexual differences in individual dental microwear design. These are probably the consequence of seasonal variations in fruit, seed and leaf availability, as well as differences in feeding preference between males and females due to distinct energy requirements during periods of rutting, gestation or giving birth. Nevertheless, further investigations using two-block Partial Least-Squares analysis show no strong relationship between individual stomach contents and microwear texture. This is an expected result, assuming that stomach contents are composed of food items ingested during the last few hours whereas dental microwear texture records the physical properties of items eaten over periods of days or weeks. Conclusions/Significance Microwear 3D scale-sensitive fractal analysis does detect differences in diet ranging from the inter-feeding styles scale to the intra-population between-season and between-sex scales. It is therefore a possible tool, to be used with caution, in the further exploration of the feeding

  14. In-Depth Assessment of Within-Individual and Inter-Individual Variation in the B Cell Receptor Repertoire

    PubMed Central

    Galson, Jacob D.; Trück, Johannes; Fowler, Anna; Münz, Márton; Cerundolo, Vincenzo; Pollard, Andrew J.; Lunter, Gerton; Kelly, Dominic F.

    2015-01-01

    High-throughput sequencing of the B cell receptor (BCR) repertoire can provide rapid characterization of the B cell response in a wide variety of applications in health, after vaccination and in infectious, inflammatory and immune-driven disease, and is starting to yield clinical applications. However, the interpretation of repertoire data is compromised by a lack of studies to assess the intra and inter-individual variation in the BCR repertoire over time in healthy individuals. We applied a standardized isotype-specific BCR repertoire deep sequencing protocol to a single highly sampled participant, and then evaluated the method in 9 further participants to comprehensively describe such variation. We assessed total repertoire metrics of mutation, diversity, VJ gene usage and isotype subclass usage as well as tracking specific BCR sequence clusters. There was good assay reproducibility (both in PCR amplification and biological replicates), but we detected striking fluctuations in the repertoire over time that we hypothesize may be due to subclinical immune activation. Repertoire properties were unique for each individual, which could partly be explained by a decrease in IgG2 with age, and genetic differences at the immunoglobulin locus. There was a small repertoire of public clusters (0.5, 0.3, and 1.4% of total IgA, IgG, and IgM clusters, respectively), which was enriched for expanded clusters containing sequences with suspected specificity toward antigens that should have been historically encountered by all participants through prior immunization or infection. We thus provide baseline BCR repertoire information that can be used to inform future study design, and aid in interpretation of results from these studies. Furthermore, our results indicate that BCR repertoire studies could be used to track changes in the public repertoire in and between populations that might relate to population immunity against infectious diseases, and identify the characteristics of

  15. Genome-wide DNA methylation map of human neutrophils reveals widespread inter-individual epigenetic variation

    PubMed Central

    Chatterjee, Aniruddha; Stockwell, Peter A.; Rodger, Euan J.; Duncan, Elizabeth J.; Parry, Matthew F.; Weeks, Robert J.; Morison, Ian M.

    2015-01-01

    The extent of variation in DNA methylation patterns in healthy individuals is not yet well documented. Identification of inter-individual epigenetic variation is important for understanding phenotypic variation and disease susceptibility. Using neutrophils from a cohort of healthy individuals, we generated base-resolution DNA methylation maps to document inter-individual epigenetic variation. We identified 12851 autosomal inter-individual variably methylated fragments (iVMFs). Gene promoters were the least variable, whereas gene body and upstream regions showed higher variation in DNA methylation. The iVMFs were relatively enriched in repetitive elements compared to non-iVMFs, and were associated with genome regulation and chromatin function elements. Further, variably methylated genes were disproportionately associated with regulation of transcription, responsive function and signal transduction pathways. Transcriptome analysis indicates that iVMF methylation at differentially expressed exons has a positive correlation and local effect on the inclusion of that exon in the mRNA transcript. PMID:26612583

  16. Structural insights and functional implications of inter-individual variability in β2-adrenergic receptor

    PubMed Central

    Tandale, Aditi; Joshi, Manali; Sengupta, Durba

    2016-01-01

    The human β2-adrenergic receptor (β2AR) belongs to the G protein-coupled receptor (GPCR) family and due to its central role in bronchodilation, is an important drug target. The inter-individual variability in β2AR has been implicated in disease susceptibility and differential drug response. In this work, we identified nine potentially deleterious non-synonymous single nucleotide polymorphisms (nsSNPs) using a consensus approach. The deleterious nsSNPs were found to cluster near the ligand binding site and towards the G-protein binding site. To assess their molecular level effects, we built structural models of these receptors and performed atomistic molecular dynamics simulations. Most notably, in the Phe290Ser variant we observed the rotameric flip of Trp2866.48, a putative activation switch that has not been reported in β2AR thus far. In contrast, the variant Met82Lys was found to be the most detrimental to epinephrine binding. Additionally, a few of the nsSNPs were seen to cause perturbations to the lipid bilayer, while a few lead to differences at the G-protein coupling site. We are thus able to classify the variants as ranging from activating to damaging, prioritising them for experimental studies. PMID:27075228

  17. Inter-individual and seasonal weight variation in rural Nepali women.

    PubMed

    Panter-Brick, C

    1995-04-01

    Changes in body weight were examined for non-pregnant women in rural Nepal, using 183 anthropometric measures between the early winter and monsoon seasons in 1982, 1982-83, 1990-91 and 1993. The women gained weight when work loads decreased after the monsoon, but despite substantial changes in total energy expenditure, which were out of phase with changes in food intake, seasonal changes were small, averaging only up to 2.6% of initial body weight. There were notable differences between individual women, changes in body weight ranging from -5.6 kg to 4.8 kg. Weight change was examined with respect to lactation status, age, body mass index, mid upper arm circumference and skinfolds as well as total energy expenditure and intake. Nonlactating women, very thin women and women aged under 25 years gained more weight than their counterparts, both before and after the monsoon. Data for a sub-sample in 1982-83 indicated that women who maintained high physical activity levels throughout the year were less prone to weight loss than women whose activity fluctuated between seasons. Initial energy reserves, age-related maturation factors, levels of physical activity and energy intake combine to produce the notable inter-individual variation in body weight changes observed in this population. PMID:7738083

  18. Statistically Characterizing Intra- and Inter-Individual Variability in Children with Developmental Coordination Disorder

    ERIC Educational Resources Information Center

    King, Bradley R.; Harring, Jeffrey R.; Oliveira, Marcio A.; Clark, Jane E.

    2011-01-01

    Previous research investigating children with Developmental Coordination Disorder (DCD) has consistently reported increased intra- and inter-individual variability during motor skill performance. Statistically characterizing this variability is not only critical for the analysis and interpretation of behavioral data, but also may facilitate our…

  19. Analysis of Inter-Individual Bacterial Variation in Gut of Cicada Meimuna mongolica (Hemiptera: Cicadidae)

    PubMed Central

    Zhou, Wenting; Nan, Xiaoning; Zheng, Zhou; Wei, Cong; He, Hong

    2015-01-01

    Intestinal bacterial community plays a crucial role in the nutrition, development, survival, and reproduction of insects. When compared with other insects with piercing-sucking mouthparts, the habitats of cicada nymphs and adults are totally different. However, little is known about the differences in the gut bacterial communities in the nymphs and adults within any cicada species. The diversity of bacteria in the gut of nymphs and adults of both genders of Meimuna mongolica (Distant) was studied using the denaturing gradient gel electrophoresis (DGGE) method. Few inter-individual variations among gut microbiota were observed, suggesting that M. mongolica typically harbors a limited and consistent suite of bacterial species. Bacteria in the genera Pseudomonas and Enterobacter were the predominant components of the gut microflora of M. mongolica at all life stages. Bacteria of Pantoea, Streptococcus, and Uruburuella were also widespread in the cicada samples but at relatively lower concentrations. The relative stability and similarity of the PCR-DGGE patterns indicate that all individuals of this cicada species harbor a characteristic bacterial community which is independent from developmental stages and genders. Related endosymbionts that could be harbored in bacteromes of cicadas were not detected in any gut samples, which could be related to the cicada species and the distribution of these endosymbionts in the cicada cavity, or due to some of the possible limitations of PCR-DGGE community profiling. It is worthwhile to further address if related cicada endosymbiont clades distribute in the alimentary canals and other internal organs through diagnostic PCR using group-specific primer sets. PMID:26411784

  20. The complete mitochondrial genome of the deep-sea stony coral Solenosmilia variabilis (Scleractinia, Caryophylliidae) and its inter-individual variation.

    PubMed

    Zeng, Cong; Tracey, Di M; Clark, Malcolm R; Rowden, Ashley A; Thomas, Leighton J; Gardner, Jonathan P A

    2016-05-01

    Three individual-specific DNA libraries of the deep-sea scleractinian coral Solenosmilia variabilis (Duncan, 1873) were constructed to obtain complete mitochondrial genomes using the 454 Life Science pyrosequencing system. Two mitogenomes were successfully assembled: both were 15,968 bp in length, with base composition of A (24.2%), T (41.1%), C (13.7%) and G (21.0%). The genome contains 13 protein-coding genes, 2 ribosomal RNA genes, 2 transfer RNA genes and a D-loop region. The two mitogenomes were almost identical, with only 5 nucleotide differences (0.03%), including a synonymous substitution within the nad1, nad2 and nad4L genes, and two transversions in the D-loop region. This inter-individual variation indicates that these genes and/or region are potential candidates as molecular markers for population genetic research. The mitogenome of S. variabilis will be useful for future phylogenetic and phylogeographic studies of deep-sea corals. PMID:25329254

  1. Photosensitizer dosimetry controlled PDT treatment planning reduces inter-individual variability in response to PDT

    NASA Astrophysics Data System (ADS)

    Zhou, Xiaodong; Pogue, Brian W.; Chen, Bin; Demidenko, Eugene; Joshi, Rohan; Hoopes, Jack; Hasan, Tayyaba

    2006-02-01

    -PDT and CU-PDT. The results indicate that by measuring the mean photosensitizer concentration prior to light treatment, and then adjusting the light dose appropriately, a more uniform treatment can be applied to different animals thereby reducing the inter-individual variation in the treatment outcome.

  2. Tree phyllosphere bacterial communities: exploring the magnitude of intra- and inter-individual variation among host species

    PubMed Central

    Messier, Christian; Kembel, Steven W.

    2016-01-01

    Background The diversity and composition of the microbial community of tree leaves (the phyllosphere) varies among trees and host species and along spatial, temporal, and environmental gradients. Phyllosphere community variation within the canopy of an individual tree exists but the importance of this variation relative to among-tree and among-species variation is poorly understood. Sampling techniques employed for phyllosphere studies include picking leaves from one canopy location to mixing randomly selected leaves from throughout the canopy. In this context, our goal was to characterize the relative importance of intra-individual variation in phyllosphere communities across multiple species, and compare this variation to inter-individual and interspecific variation of phyllosphere epiphytic bacterial communities in a natural temperate forest in Quebec, Canada. Methods We targeted five dominant temperate forest tree species including angiosperms and gymnosperms: Acer saccharum, Acer rubrum, Betula papyrifera, Abies balsamea and Picea glauca. For one randomly selected tree of each species, we sampled microbial communities at six distinct canopy locations: bottom-canopy (1–2 m height), the four cardinal points of mid-canopy (2–4 m height), and the top-canopy (4–6 m height). We also collected bottom-canopy leaves from five additional trees from each species. Results Based on an analysis of bacterial community structure measured via Illumina sequencing of the bacterial 16S gene, we demonstrate that 65% of the intra-individual variation in leaf bacterial community structure could be attributed to the effect of inter-individual and inter-specific differences while the effect of canopy location was not significant. In comparison, host species identity explains 47% of inter-individual and inter-specific variation in leaf bacterial community structure followed by individual identity (32%) and canopy location (6%). Discussion Our results suggest that individual

  3. Inter-individual variation in DNA repair capacity: a need for multi-pathway functional assays to promote translational DNA repair research.

    PubMed

    Nagel, Zachary D; Chaim, Isaac A; Samson, Leona D

    2014-07-01

    Why does a constant barrage of DNA damage lead to disease in some individuals, while others remain healthy? This article surveys current work addressing the implications of inter-individual variation in DNA repair capacity for human health, and discusses the status of DNA repair assays as potential clinical tools for personalized prevention or treatment of disease. In particular, we highlight research showing that there are significant inter-individual variations in DNA repair capacity (DRC), and that measuring these differences provides important biological insight regarding disease susceptibility and cancer treatment efficacy. We emphasize work showing that it is important to measure repair capacity in multiple pathways, and that functional assays are required to fill a gap left by genome wide association studies, global gene expression and proteomics. Finally, we discuss research that will be needed to overcome barriers that currently limit the use of DNA repair assays in the clinic. PMID:24780560

  4. Inter-individual variation in DNA repair capacity: a need for multi-pathway functional assays to promote translational DNA repair research.

    PubMed Central

    Nagel, Zachary D.; Chaim, Isaac. A.; Samson, Leona D.

    2014-01-01

    Why does a constant barrage of DNA damage lead to disease in some individuals, while others remain healthy? This article surveys current work addressing the implications of inter-individual variation in DNA repair capacity for human health, and discusses the status of DNA repair assays as potential clinical tools for personalized prevention or treatment of disease. In particular, we highlight research showing that there are significant inter-individual variations in DNA Repair Capacity (DRC), and that measuring these differences provides important biological insight regarding disease susceptibility and cancer treatment efficacy. We emphasize work showing that it is important to measure repair capacity in multiple pathways, and that functional assays are required to fill a gap left by genome wide association studies, global gene expression and proteomics. Finally, we discuss research that will be needed to overcome barriers that currently limit the use of DNA repair assays in the clinic. PMID:24780560

  5. Inter-individual variability in adaptation of the leg muscles following a standardised endurance training programme in young women.

    PubMed

    McPhee, Jamie S; Williams, Alun G; Degens, Hans; Jones, David A

    2010-08-01

    There is considerable inter-individual variability in adaptations to endurance training. We hypothesised that those individuals with a low local leg-muscle peak aerobic capacity (VO2peak) relative to their whole-body maximal aerobic capacity (VO2max) would experience greater muscle training adaptations compared to those with a relatively high VO2peak. 53 untrained young women completed one-leg cycling to measure VO2peak and two-leg cycling to measure VO2max. The one-leg VO2peak was expressed as a ratio of the two-leg VO2max (Ratio(1:2)). Magnetic resonance imaging was used to indicate quadriceps muscle volume. Measurements were taken before and after completion of 6 weeks of supervised endurance training. There was large inter-individual variability in the pre-training Ratio(1:2) and large variability in the magnitude of training adaptations. The pre-training Ratio(1:2) was not related to training-induced changes in VO2max (P = 0.441) but was inversely correlated with changes in one-leg VO2peak and muscle volume (P < 0.05). No relationship was found between the training-induced changes in two-leg VO2max and one-leg VO2peak (r = 0.21; P = 0.129). It is concluded that the local leg-muscle aerobic capacity and Ratio(1:2) vary from person to person and this influences the extent of muscle adaptations following standardised endurance training. These results help to explain why muscle adaptations vary between people and suggest that setting the training stimulus at a fixed percentage of VO2max might not be a good way to standardise the training stimulus to the leg muscles of different people. PMID:20369366

  6. Inter-Individual Variability in Fear of Humans and Relative Brain Size of the Species Are Related to Contemporary Urban Invasion in Birds

    PubMed Central

    Carrete, Martina; Tella, José L.

    2011-01-01

    Background Urbanization is the most prevailing cause of habitat transformation worldwide, differing from others by its intense levels of human activity. Despite its obvious impact on wildlife, it is still unclear why and how some species are able to adapt to urban settings. One possibility is that fear of humans and vehicles could preclude most species from invading cities. Species entering urban environments might be those that are more tolerant of human disturbance (i.e., tame species). Alternatively or in addition, urban invaders could be a fraction of variable species, with “tame” individuals invading urban habitats and other individuals remaining in rural areas. Methodology Using the contemporary urban invasion by birds in a recently established South American city, we tested both hypotheses by relating interspecific differences in invasiveness to their flight initiation distances (i.e., the distances at which birds flee from approaching cars, FID), as well as to their relative brain size (RBS), a correlate of measures of behavioral flexibility. Principal Findings Urban invasiveness was not significantly related to species' average rural FIDs but positively related to their RBS and inter-individual variability in FID. Moreover, FIDs were consistently lower in urban than in rural conspecifics, and the FIDs of urban individuals were within the lower-range distribution of their rural conspecifics. RBS indirectly influenced urban invasion through its positive effect on inter-individual variability in FID. Conclusions/Significance Urban invaders do not appear to be individuals from apparently tame species, but rather tame individuals from species with a variable response regarding fear of people. Given the positive relationship between RBS and inter-individual variability in FID, our results suggest that behavioural flexibility should be regarded as a specific trait encompassing variability among individuals. Further research is needed to ascertain the

  7. Individual differences in cognition, affect, and performance: Behavioral, neuroimaging, and molecular genetic approaches

    PubMed Central

    Parasuraman, Raja; Jiang, Yang

    2012-01-01

    We describe the use of behavioral, neuroimaging, and genetic methods to examine individual differences in cognition and affect, guided by three criteria: (1) relevance to human performance in work and everyday settings; (2) interactions between working memory, decision-making, and affective processing; and (3) examination of individual differences. The results of behavioral, functional MRI (fMRI), event-related potential (ERP), and molecular genetic studies show that analyses at the group level often mask important findings associated with sub-groups of individuals. Dopaminergic/noradrenergic genes influencing prefrontal cortex activity contribute to inter-individual variation in working memory and decision behavior, including performance in complex simulations of military decision-making. The interactive influences of individual differences in anxiety, sensation seeking, and boredom susceptibility on evaluative decision-making can be systematically described using ERP and fMRI methods. We conclude that a multi-modal neuroergonomic approach to examining brain function (using both neuroimaging and molecular genetics) can be usefully applied to understanding individual differences in cognition and affect and has implications for human performance at work. PMID:21569853

  8. Inter-individual differences in the experience of negative emotion predict variations in functional brain architecture.

    PubMed

    Petrican, Raluca; Saverino, Cristina; Shayna Rosenbaum, R; Grady, Cheryl

    2015-12-01

    Current evidence suggests that two spatially distinct neuroanatomical networks, the dorsal attention network (DAN) and the default mode network (DMN), support externally and internally oriented cognition, respectively, and are functionally regulated by a third, frontoparietal control network (FPC). Interactions among these networks contribute to normal variations in cognitive functioning and to the aberrant affective profiles present in certain clinical conditions, such as major depression. Nevertheless, their links to non-clinical variations in affective functioning are still poorly understood. To address this issue, we used fMRI to measure the intrinsic functional interactions among these networks in a sample of predominantly younger women (N=162) from the Human Connectome Project. Consistent with the previously documented dichotomous motivational orientations (i.e., withdrawal versus approach) associated with sadness versus anger, we hypothesized that greater sadness would predict greater DMN (rather than DAN) functional dominance, whereas greater anger would predict the opposite. Overall, there was evidence of greater DAN (rather than DMN) functional dominance, but this pattern was modulated by current experience of specific negative emotions, as well as subclinical depressive and anxiety symptoms. Thus, greater levels of currently experienced sadness and subclinical depression independently predicted weaker DAN functional dominance (i.e., weaker DAN-FPC functional connectivity), likely reflecting reduced goal-directed attention towards the external perceptual environment. Complementarily, greater levels of currently experienced anger and subclinical anxiety predicted greater DAN functional dominance (i.e., greater DAN-FPC functional connectivity and, for anxiety only, also weaker DMN-FPC coupling). Our findings suggest that distinct affective states and subclinical mood symptoms have dissociable neural signatures, reflective of the symbiotic relationship between cognitive processes and emotional states. PMID:26302674

  9. Breed-specific companions--inter-individual distances reflect isolating mechanisms within domesticated chickens (Gallus gallus f.d.).

    PubMed

    Tiemann, Inga; Rehkämper, Gerd

    2008-06-15

    White Crested Polish (WCP) chickens are an interesting breed because of skull anatomy (crest), brain size and composition. This makes them attractive to investigate processes of selection that could parallel a step towards speciation in terms of ethological isolation. Lohmann Brown Classic (BL) and Red Leghorn (RL) were selected as comparative breeds to detect whether WCPs flock together as shown by shorter inter-individual distances within WCP than across breeds. WCP and BL were observed in the first year whereas RL served as comparative breed to WCP in the second year. Eggs of both breeds of each year were incubated at the same time, and chicks hatched and were raised together. Three young hens of each breed were randomly chosen and observed weekly in an open field situation for 20 min between the first and 31st week of life. Intra-breed distances differed significantly from those distances measured across breeds. Results demonstrate breed-specific flocking within observed breeds. This flocking behaviour may reflect breed-specific social and sexual preferences. Our observations indicate that domestic breeds may represent an ethological entity. Selective processes controlled by human intervention as given in domestication may therefore to be set in parallel to evolutionary processes. PMID:18498945

  10. Fully unsupervised inter-individual IR spectral histology of paraffinized tissue sections of normal colon.

    PubMed

    Nguyen, Thi Nguyet Que; Jeannesson, Pierre; Groh, Audrey; Piot, Olivier; Guenot, Dominique; Gobinet, Cyril

    2016-05-01

    In label-free Fourier-transform infrared histology, spectral images are individually recorded from tissue sections, pre-processed and clustered. Each single resulting color-coded image is annotated by a pathologist to obtain the best possible match with tissue structures revealed after Hematoxylin-Eosin staining. However, the main limitations of this approach are the empirical choice of the number of clusters in unsupervised classification, and the marked color heterogeneity between the clustered spectral images. Here, using normal murine and human colon tissues, we developed an automatic multi-image spectral histology to simultaneously analyze a set of spectral images (8 images mice samples and 72 images human ones). This procedure consisted of a joint Extended Multiplicative Signal Correction (EMSC) to numerically deparaffinize the tissue sections, followed by an automated joint K-Means (KM) clustering using the hierarchical double application of Pakhira-Bandyopadhyay-Maulik (PBM) validity index. Using this procedure, the main murine and human colon histological structures were correctly identified at both the intra- and the inter-individual levels, especially the crypts, secreted mucus, lamina propria and submucosa. Here, we show that batched multi-image spectral histology procedure is insensitive to the reference spectrum but highly sensitive to the paraffin model of joint EMSC. In conclusion, combining joint EMSC and joint KM clustering by double PBM application allows to achieve objective and automated batched multi-image spectral histology. PMID:26872124

  11. Intra- and Inter-Individual Variation in Self-Reported Code-Switching Patterns of Adult Multilinguals

    ERIC Educational Resources Information Center

    Dewaele, Jean-Marc; Li, Wei

    2014-01-01

    The present study is a large-scale quantitative analysis of intra-individual variation (linked to type of interlocutor) and inter-individual variation (linked to multilingualism, sociobiographical variables and three personality traits) in self-reported frequency of code-switching (CS) among 2116 multilinguals. We found a significant effect of…

  12. INTER-INDIVIDUAL VARIATION IN VERTEBRAL KINEMATICS AFFECTS PREDICTIONS OF NECK MUSCULOSKELETAL MODELS

    PubMed Central

    Nevins, Derek D.; Zheng, Liying; Vasavada, Anita N.

    2014-01-01

    Experimental studies have found significant variation in cervical intervertebral kinematics (IVK) among healthy subjects, but the effect of this variation on biomechanical properties, such as neck strength, has not been explored. The goal of this study was to quantify variation in model predictions of extension strength, flexion strength and gravitational demand (the ratio of gravitational load from the weight of the head to neck muscle extension strength), due to inter-subject variation in IVK. IVK were measured from sagittal radiographs of twenty-four subjects (14F, 10M) in five postures: maximal extension, mid-extension, neutral, mid-flexion, and maximal flexion. IVK were defined by the position (anterior-posterior and superior-inferior) of each cervical vertebra with respect to T1 and its angle with respect to horizontal, and fit with a cubic polynomial over the range of motion. The IVK of each subject were scaled and incorporated into musculoskeletal models to create models that were identical in muscle force- and moment-generating properties but had subject-specific kinematics. The effect of inter-subject variation in IVK was quantified using the coefficient of variation (COV), the ratio of the standard deviation to the mean. COV of extension strength ranged from 8 – 15% over the range of motion, but COV of flexion strength were 20 – 80%. Moreover, the COV of gravitational demand was 80 – 90%, because the gravitational demand is affected by head position as well as neck strength. These results indicate that including inter-individual variation in models is important for evaluating neck musculoskeletal biomechanical properties. PMID:25234351

  13. Time-on-task decrement in vigilance is modulated by inter-individual vulnerability to homeostatic sleep pressure manipulation.

    PubMed

    Maire, Micheline; Reichert, Carolin F; Gabel, Virginie; Viola, Antoine U; Krebs, Julia; Strobel, Werner; Landolt, Hans-Peter; Bachmann, Valérie; Cajochen, Christian; Schmidt, Christina

    2014-01-01

    Under sleep loss, vigilance is reduced and attentional failures emerge progressively. It becomes difficult to maintain stable performance over time, leading to growing performance variability (i.e., state instability) in an individual and among subjects. Task duration plays a major role in the maintenance of stable vigilance levels, such that the longer the task, the more likely state instability will be observed. Vulnerability to sleep-loss-dependent performance decrements is highly individual and is also modulated by a polymorphism in the human clock gene PERIOD3 (PER3). By combining two different protocols, we manipulated sleep-wake history by once extending wakefulness for 40 h (high sleep pressure condition) and once by imposing a short sleep-wake cycle by alternating 160 min of wakefulness and 80 min naps (low sleep pressure condition) in a within-subject design. We observed that homozygous carriers of the long repeat allele of PER3 (PER3 (5/5) ) experienced a greater time-on-task dependent performance decrement (i.e., a steeper increase in the number of lapses) in the Psychomotor Vigilance Task compared to the carriers of the short repeat allele (PER3 (4/4) ). These genotype-dependent effects disappeared under low sleep pressure conditions, and neither motivation, nor perceived effort accounted for these differences. Our data thus suggest that greater sleep-loss related attentional vulnerability based on the PER3 polymorphism is mirrored by a greater state instability under extended wakefulness in the short compared to the long allele carriers. Our results undermine the importance of time-on-task related aspects when investigating inter-individual differences in sleep loss-induced behavioral vulnerability. PMID:24639634

  14. Inter-individual and intra-individual variation of the effects of pulsed RF EMF exposure on the human sleep EEG.

    PubMed

    Lustenberger, Caroline; Murbach, Manuel; Tüshaus, Laura; Wehrle, Flavia; Kuster, Niels; Achermann, Peter; Huber, Reto

    2015-04-01

    Pulse-modulated radiofrequency electromagnetic fields (RF EMF) can alter brain activity during sleep; increases of electroencephalographic (EEG) power in the sleep spindle (13.75-15.25 Hz) and delta-theta (1.25-9 Hz) frequency range have been reported. These field effects show striking inter-individual differences. However, it is still unknown whether individual subjects react in a similar way when repeatedly exposed. Thus, our study aimed to investigate inter-individual variation and intra-individual stability of field effects. To do so, we exposed 20 young male subjects twice for 30 min prior to sleep to the same amplitude modulated 900 MHz (2 Hz pulse, 20 Hz Gaussian low-pass filter and a ratio of peak-to-average of 4) RF EMF (spatial peak absorption of 2 W/kg averaged over 10 g) 2 weeks apart. The topographical analysis of EEG power during all-night non-rapid eye movement sleep revealed: (1) exposure-related increases in delta-theta frequency range in several fronto-central electrodes; and (2) no differences in spindle frequency range. We did not observe reproducible within-subject RF EMF effects on sleep spindle and delta-theta activity in the sleep EEG and it remains unclear whether a biological trait of how the subjects' brains react to RF EMF exists. PMID:25690404

  15. Medical and Genetic Differences in the Adverse Impact of Sleep Loss on Performance: Ethical Considerations for the Medical Profession

    PubMed Central

    Czeisler, Charles A.

    2009-01-01

    The Institute of Medicine recently concluded that-on average-medical residents make more serious medical errors and have more motor vehicle crashes when they are deprived of sleep. In the interest of public safety, society has required limitations on work hours in many other safety sensitive occupations, including transportation and nuclear power generation. Those who argue in favor of traditional extended duration resident work hours often suggest that there are inter- individual differences in response to acute sleep loss or chronic sleep deprivation, implying that physicians may be more resistant than the average person to the detrimental effects of sleep deprivation on performance, although there is no evidence that physicians are particularly resistant to such effects. Indeed, recent investigations have identified genetic polymorphisms that may convey a relative resistance to the effects of prolonged wakefulness on a subset of the healthy population, although there is no evidence that physicians are over-represented in this cohort. Conversely, there are also genetic polymorphisms, sleep disorders and other inter-individual differences that appear to convey an increased vulnerability to the performance-impairing effects of 24 hours of wakefulness. Given the magnitude of inter-individual differences in the effect of sleep loss on cognitive performance, and the sizeable proportion of the population affected by sleep disorders, hospitals face a number of ethical dilemmas. How should the work hours of physicians be limited to protect patient safety optimally? For example, some have argued that, in contrast to other professions, work schedules that repeatedly induce acute and chronic sleep loss are uniquely essential to the training of physicians. If evidence were to prove this premise to be correct, how should such training be ethically accomplished in the quartile of physicians and surgeons who are most vulnerable to the effects of sleep loss on performance

  16. Medical and genetic differences in the adverse impact of sleep loss on performance: ethical considerations for the medical profession.

    PubMed

    Czeisler, Charles A

    2009-01-01

    The Institute of Medicine recently concluded that-on average-medical residents make more serious medical errors and have more motor vehicle crashes when they are deprived of sleep. In the interest of public safety, society has required limitations on work hours in many other safety sensitive occupations, including transportation and nuclear power generation. Those who argue in favor of traditional extended duration resident work hours often suggest that there are inter- individual differences in response to acute sleep loss or chronic sleep deprivation, implying that physicians may be more resistant than the average person to the detrimental effects of sleep deprivation on performance, although there is no evidence that physicians are particularly resistant to such effects. Indeed, recent investigations have identified genetic polymorphisms that may convey a relative resistance to the effects of prolonged wakefulness on a subset of the healthy population, although there is no evidence that physicians are over-represented in this cohort. Conversely, there are also genetic polymorphisms, sleep disorders and other inter-individual differences that appear to convey an increased vulnerability to the performance-impairing effects of 24 hours of wakefulness. Given the magnitude of inter-individual differences in the effect of sleep loss on cognitive performance, and the sizeable proportion of the population affected by sleep disorders, hospitals face a number of ethical dilemmas. How should the work hours of physicians be limited to protect patient safety optimally? For example, some have argued that, in contrast to other professions, work schedules that repeatedly induce acute and chronic sleep loss are uniquely essential to the training of physicians. If evidence were to prove this premise to be correct, how should such training be ethically accomplished in the quartile of physicians and surgeons who are most vulnerable to the effects of sleep loss on performance

  17. Inter-individual variation in expression: a missing link in biomarker biology?

    PubMed

    Little, Peter F R; Williams, Rohan B H; Wilkins, Marc R

    2009-01-01

    The past decade has seen an explosion of variation data demonstrating that diversity of both protein-coding sequences and of regulatory elements of protein-coding genes is common and of functional importance. In this article, we argue that genetic diversity can no longer be ignored in studies of human biology, even research projects without explicit genetic experimental design, and that this knowledge can, and must, inform research. By way of illustration, we focus on the potential role of genetic data in case-control studies to identify and validate cancer protein biomarkers. We argue that a consideration of genetics, in conjunction with proteomic biomarker discovery projects, should improve the proportion of biomarkers that can accurately classify patients. PMID:19010558

  18. Inter-individual variation in nucleotide excision repair pathway is modulated by non-synonymous polymorphisms in ERCC4 and MBD4 genes.

    PubMed

    Allione, Alessandra; Guarrera, Simonetta; Russo, Alessia; Ricceri, Fulvio; Purohit, Rituraj; Pagnani, Andrea; Rosa, Fabio; Polidoro, Silvia; Voglino, Floriana; Matullo, Giuseppe

    2013-01-01

    Inter-individual differences in DNA repair capacity (DRC) may lead to genome instability and, consequently, modulate individual cancer risk. Among the different DNA repair pathways, nucleotide excision repair (NER) is one of the most versatile, as it can eliminate a wide range of helix-distorting DNA lesions caused by ultraviolet light irradiation and chemical mutagens. We performed a genotype-phenotype correlation study in 122 healthy subjects in order to assess if any associations exist between phenotypic profiles of NER and DNA repair gene single nucleotide polymorphisms (SNPs). Individuals were genotyped for 768 SNPs with a custom Illumina Golden Gate Assay, and peripheral blood mononuclear cells (PBMCs) of the same subjects were tested for a NER comet assay to measure DRC after challenging cells by benzo(a)pyrene diolepoxide (BPDE). We observed a large inter-individual variability of NER capacity, with women showing a statistically significant lower DRC (mean ± SD: 6.68 ± 4.76; p = 0.004) than men (mean ± SD: 8.89 ± 5.20). Moreover, DRC was significantly lower in individuals carrying a variant allele for the ERCC4 rs1800124 non-synonymous SNP (nsSNP) (p = 0.006) and significantly higher in subjects with the variant allele of MBD4 rs2005618 SNP (p = 0.008), in linkage disequilibrium (r(2) = 0.908) with rs10342 nsSNP. Traditional in silico docking approaches on protein-DNA and protein-protein interaction showed that Gly875 variant in ERCC4 (rs1800124) decreases the DNA-protein interaction and that Ser273 and Thr273 variants in MBD4 (rs10342) indicate complete loss of protein-DNA interactions. Our results showed that NER inter-individual capacity can be modulated by cross-talk activity involving nsSNPs in ERCC4 and MBD4 genes, and they suggested to better investigate SNP effect on cancer risk and response to chemo- and radiotherapies. PMID:24004570

  19. Identification of intra- and inter-individual metabolite variation in plasma metabolite profiles of cats and dogs.

    PubMed

    Colyer, Alison; Gilham, Matthew S; Kamlage, Beate; Rein, Dietrich; Allaway, David

    2011-10-01

    The purpose of the present study was first to identify drivers of variance in plasma metabolite profiles of cats and dogs that may affect the interpretation of nutritional metabolomic studies. A total of fourteen cats and fourteen dogs housed in environmentally enriched accommodation were fed a single batch of diet to maintain body weight. Fasting blood samples were taken on days 14, 16 and 18 of the study. Gas chromatography-mass spectrometry (GC-MS), liquid chromatography (LC)-MS/MS and solid-phase extraction-LC-MS/MS analyses were used for metabolite profiling. Principal component (PC) analysis that indicated 31 and 27 % of the variance was explained in PC1 and PC2 for cats and dogs, respectively, with most individuals occupying a unique space. As the individual was a major driver of variance in the plasma metabolome, the second objective was to identify metabolites associated with the individual variation observed. The proportion of intra- and inter-individual variance was calculated for 109 cat and 101 dog metabolites with a low intra-individual variance (SD < 0.05). Of these, fifteen cat and six dog metabolites had inter-individual variance accounting for at least 90 % of the total variance. There were four metabolites common to both species (campesterol, DHA, a cholestenol and a sphingosine moiety). Many of the metabolites with >75 % inter-individual variance were common to both species and to similar areas of metabolism. In summary, the individual is an important driver of variance in the fasted plasma metabolome, and specific metabolites and areas of metabolism may be differentially regulated by individuals in two companion animal species. PMID:22005413

  20. Understanding inter-individual variability in purpose in life: Longitudinal findings from the VA Normative Aging Study

    PubMed Central

    Hill, Patrick L.; Turiano, Nicholas A.; Spiro, Avron; Mroczek, Daniel K.

    2015-01-01

    Research has demonstrated the importance of having a purpose in older adulthood; however, little is known about whether and how individuals vary on sense of purpose over time. The current study examined patterns of mean- and individual-level change in purpose among men in the Veterans Affairs Normative Aging Study (n = 587; Mage = 74 years) across a three-year span. Findings demonstrate that while little mean-level change was present, there was inter-individual variability in change. Further research is needed to understand why these changes occur, as age, health status, and personality failed to predict individual fluctuations in purpose. PMID:26146887

  1. Measurement invariance within and between individuals: a distinct problem in testing the equivalence of intra- and inter-individual model structures

    PubMed Central

    Adolf, Janne; Schuurman, Noémi K.; Borkenau, Peter; Borsboom, Denny; Dolan, Conor V.

    2014-01-01

    We address the question of equivalence between modeling results obtained on intra-individual and inter-individual levels of psychometric analysis. Our focus is on the concept of measurement invariance and the role it may play in this context. We discuss this in general against the background of the latent variable paradigm, complemented by an operational demonstration in terms of a linear state-space model, i.e., a time series model with latent variables. Implemented in a multiple-occasion and multiple-subject setting, the model simultaneously accounts for intra-individual and inter-individual differences. We consider the conditions—in terms of invariance constraints—under which modeling results are generalizable (a) over time within subjects, (b) over subjects within occasions, and (c) over time and subjects simultaneously thus implying an equivalence-relationship between both dimensions. Since we distinguish the measurement model from the structural model governing relations between the latent variables of interest, we decompose the invariance constraints into those that involve structural parameters and those that involve measurement parameters and relate to measurement invariance. Within the resulting taxonomy of models, we show that, under the condition of measurement invariance over time and subjects, there exists a form of structural equivalence between levels of analysis that is distinct from full structural equivalence, i.e., ergodicity. We demonstrate how measurement invariance between and within subjects can be tested in the context of high-frequency repeated measures in personality research. Finally, we relate problems of measurement variance to problems of non-ergodicity as currently discussed and approached in the literature. PMID:25346701

  2. IRF5 Risk Polymorphisms Contribute to Inter-Individual Variance in Pattern-Recognition Receptor-Mediated Cytokine Secretion in Human Monocyte-Derived Cells

    PubMed Central

    Hedl, Matija; Abraham, Clara

    2012-01-01

    Monocyte-derived cells display highly variable cytokine secretion upon pattern-recognition receptor (PRR) stimulation across individuals; such variability likely affects inter-individual inflammatory/autoimmune disease susceptibility. To define mechanisms for this heterogeneity, we examined pattern recognition receptor (PRR)-induced monocyte-derived-cell cytokine secretion from a large cohort healthy individuals. Although cytokine secretion ranged widely among individuals, the magnitude of cytokine induction after individual Nod2 and TLR2 stimulation (a cohort of 86 individuals) or stimulation of multiple TLRs (a cohort of 77 individuals), either alone or in combination with Nod2, was consistent intra-individually across these stimuli. Nod2 and TLRs signal through interferon-regulatory-factor-5 (IRF5) and common IRF5 polymorphisms confer risk for autoimmunity. We find that cells from rs2004640 IRF5 risk-associated allele carriers secrete increased cytokines upon individual or synergistic PRR stimulation in a gene dose- and ligand dose-dependent manner in both monocyte-derived dendritic cells and macrophages. IRF5 expression knockdown in IRF5-risk-allele carrier cells significantly decreases PRR-induced cytokines. Moreover, we find that IRF5 knockdown profoundly decreases Nod2-mediated MAPK and NF-κB pathway activation, whereas the PI3K and mTOR pathways are not impaired. Finally, the IRF5 rs2004640 polymorphism is a major determinant of the variance (r2=0.53) in Nod2-induced cytokine secretion by monocyte-derived cells from different individuals. We therefore show a profound contribution of a single gene to the variance in inter-individual PRR-induced cytokines. The hyper-responsiveness of IRF5 disease-associated polymorphisms to a wide spectrum of microbial triggers has broad implications on global immunological responses, host defenses against pathogens and inflammatory/autoimmune disease susceptibility. PMID:22544929

  3. Measurement invariance within and between individuals: a distinct problem in testing the equivalence of intra- and inter-individual model structures.

    PubMed

    Adolf, Janne; Schuurman, Noémi K; Borkenau, Peter; Borsboom, Denny; Dolan, Conor V

    2014-01-01

    We address the question of equivalence between modeling results obtained on intra-individual and inter-individual levels of psychometric analysis. Our focus is on the concept of measurement invariance and the role it may play in this context. We discuss this in general against the background of the latent variable paradigm, complemented by an operational demonstration in terms of a linear state-space model, i.e., a time series model with latent variables. Implemented in a multiple-occasion and multiple-subject setting, the model simultaneously accounts for intra-individual and inter-individual differences. We consider the conditions-in terms of invariance constraints-under which modeling results are generalizable (a) over time within subjects, (b) over subjects within occasions, and (c) over time and subjects simultaneously thus implying an equivalence-relationship between both dimensions. Since we distinguish the measurement model from the structural model governing relations between the latent variables of interest, we decompose the invariance constraints into those that involve structural parameters and those that involve measurement parameters and relate to measurement invariance. Within the resulting taxonomy of models, we show that, under the condition of measurement invariance over time and subjects, there exists a form of structural equivalence between levels of analysis that is distinct from full structural equivalence, i.e., ergodicity. We demonstrate how measurement invariance between and within subjects can be tested in the context of high-frequency repeated measures in personality research. Finally, we relate problems of measurement variance to problems of non-ergodicity as currently discussed and approached in the literature. PMID:25346701

  4. Different differences: The use of ‘genetic ancestry’ versus race in biomedical human genetic research

    PubMed Central

    Fujimura, Joan H.; Rajagopalan, Ramya

    2011-01-01

    This article presents findings from our ethnographic research on biomedical scientists’ studies of human genetic variation and common complex disease. We examine the socio-material work involved in genome-wide association studies (GWAS) and discuss whether, how, and when notions of race and ethnicity are or are not used. We analyze how researchers produce simultaneously different kinds of populations and population differences. Although many geneticists use race in their analyses, we find some who have invented a statistical genetics method and associated software that they use specifically to avoid using categories of race in their genetics analysis. Their method allows them to operationalize their concept of ‘genetic ancestry’ without resorting to notions of race and ethnicity. We focus on the construction and implementation of the software’s algorithms, and discuss the consequences and implications of the software technology for debates and policies around the use of race in genetics research. We also demonstrate that the production and use of their method involves a dynamic and fluid assemblage of actors in various disciplines responding to disciplinary and sociopolitical contexts and concerns. This assemblage also includes particular discourses on human history and geography as they become entangled with research on genetic markers and disease. We introduce the concept of ‘genome geography’, to analyze how some researchers studying human genetic variation ‘locate’ stretches of DNA in different places and times. The concept of genetic ancestry and the practice of genome geography rely on old discourses, but they also incorporate new technologies, infrastructures, and political and scientific commitments. Some of these new technologies provide opportunities to change some of our institutional and cultural forms and frames around notions of difference and similarity. Neverthless, we also highlight the slipperiness of genome geography and the

  5. CYP2D6 Genetic Polymorphisms and Phenotypes in Different Ethnicities of Malaysian Breast Cancer Patients.

    PubMed

    Chin, Fee Wai; Chan, Soon Choy; Abdul Rahman, Sabariah; Noor Akmal, Sharifah; Rosli, Rozita

    2016-01-01

    The cytochrome P450, family 2, subfamily D, polypeptide 6 (CYP2D6) is an enzyme that is predominantly involved in the metabolism of tamoxifen. Genetic polymorphisms of the CYP2D6 gene may contribute to inter-individual variability in tamoxifen metabolism, which leads to the differences in clinical response to tamoxifen among breast cancer patients. In Malaysia, the knowledge on CYP2D6 genetic polymorphisms as well as metabolizer status in Malaysian breast cancer patients remains unknown. Hence, this study aimed to comprehensively identify CYP2D6 genetic polymorphisms among 80 Malaysian breast cancer patients. The genetic polymorphisms of all the 9 exons of CYP2D6 gene were identified using high-resolution melting analysis and confirmed by DNA sequencing. Seven CYP2D6 alleles consisting of CYP2D6*1, CYP2D6*2, CYP2D6*4, CYP2D6*10, CYP2D6*39, CYP2D6*49, and CYP2D6*75 were identified in this study. Among these alleles, CYP2D6*10 is the most common allele in both Malaysian Malay (54.8%) and Chinese (71.4%) breast cancer patients, whereas CYP2D6*4 in Malaysian Indian (28.6%) breast cancer patients. In relation to CYP2D6 genotype, CYP2D6*10/*10 is more frequently observed in both Malaysian Malay (28.9%) and Chinese (57.1%) breast cancer patients, whereas CYP2D6*4/*10 is more frequently observed in Malaysian Indian (42.8%) breast cancer patients. In terms of CYP2D6 phenotype, 61.5% of Malaysian Malay breast cancer patients are predicted as extensive metabolizers in which they are most likely to respond well to tamoxifen therapy. However, 57.1% of Chinese as well as Indian breast cancer patients are predicted as intermediate metabolizers and they are less likely to gain optimal benefit from the tamoxifen therapy. This is the first report of CYP2D6 genetic polymorphisms and phenotypes in Malaysian breast cancer patients for different ethnicities. These data may aid clinicians in selecting an optimal drug therapy for Malaysian breast cancer patients, hence improve the

  6. Inter-individual variability of forces and modular muscle coordination in cycling: a study on untrained subjects.

    PubMed

    De Marchis, Cristiano; Schmid, Maurizio; Bibbo, Daniele; Bernabucci, Ivan; Conforto, Silvia

    2013-12-01

    The aim of this study was to investigate the muscle coordination underlying pedaling in untrained subjects by using the muscle synergies paradigm, and to connect it with the inter-individual variability of EMG patterns and applied forces. Nine subjects performed a pedaling exercise on a cycle-simulator. Applied forces were recorded by means of instrumented pedals able to measure two force components. EMG signals were recorded from eight muscles of the dominant leg, and Nonnegative Matrix Factorization was applied to extract muscle synergy vectors W and time-varying activation coefficients H. Inter-individual variability was assessed for EMG patterns, force profiles, and H. Four modules were sufficient to reconstruct the muscle activation repertoire for all the subjects (variance accounted for >90% for each muscle). These modules were found to be highly similar between subjects in terms of W (mean r=.89), while most of the variability in force profiles and EMG patterns was reflected, in the muscle synergy structure, in the variability of H. These four modules have a functional interpretation when related to force distribution along the pedaling cycle, and the structure of W is shared with that present in human walking, suggesting the existence of a modular motor control in humans. PMID:24060224

  7. Intra- and inter-individual variation in flight direction in a migratory butterfly co-vary with individual mobility.

    PubMed

    Larranaga, Nicolas; Baguette, Michel; Calvez, Olivier; Trochet, Audrey; Ducatez, Simon; Legrand, Delphine

    2013-08-15

    Flight direction is a major component of an animal's migratory success. However, few studies have focused on variation in flight direction both between and within individuals, which is likely to be correlated with other traits implied in migration processes. We report patterns of intra- and inter-individual variation in flight direction in the large white butterfly Pieris brassicae. The presence of inter-individual variation in flight direction for individuals tested in the same conditions suggests that this trait is inherited in P. brassicae and we propose that a rapid loss of migratory skills may exist in the absence of selection for migration. The magnitude of intra-individual variation was negatively correlated to two surrogates of the potential for migration: mobility and wing length. Highly mobile and longed-winged individuals within the same family were found to fly in similar directions, whereas less mobile and short-winged individuals displayed divergent flight direction compared with the average direction of their kin. There was also a negative correlation between the variance to the mean flight direction of a family and its average mobility, but no correlation with wing length. We discuss these issues in terms of the evolution of traits potentially implied in both migration and dispersal in P. brassicae. PMID:23661774

  8. Intra- and inter-individual variation of BIS-index® and Entropy® during controlled sedation with midazolam/remifentanil and dexmedetomidine/remifentanil in healthy volunteers: an interventional study

    PubMed Central

    Haenggi, Matthias; Ypparila-Wolters, Heidi; Hauser, Kathrin; Caviezel, Claudio; Takala, Jukka; Korhonen, Ilkka; Jakob, Stephan M

    2009-01-01

    Introduction We studied intra-individual and inter-individual variability of two online sedation monitors, BIS® and Entropy®, in volunteers under sedation. Methods Ten healthy volunteers were sedated in a stepwise manner with doses of either midazolam and remifentanil or dexmedetomidine and remifentanil. One week later the procedure was repeated with the remaining drug combination. The doses were adjusted to achieve three different sedation levels (Ramsay Scores 2, 3 and 4) and controlled by a computer-driven drug-delivery system to maintain stable plasma concentrations of the drugs. At each level of sedation, BIS® and Entropy® (response entropy and state entropy) values were recorded for 20 minutes. Baseline recordings were obtained before the sedative medications were administered. Results Both inter-individual and intra-individual variability increased as the sedation level deepened. Entropy® values showed greater variability than BIS® values, and the variability was greater during dexmedetomidine/remifentanil sedation than during midazolam/remifentanil sedation. Conclusions The large intra-individual and inter-individual variability of BIS® and Entropy® values in sedated volunteers makes the determination of sedation levels by processed electroencephalogram (EEG) variables impossible. Reports in the literature which draw conclusions based on processed EEG variables obtained from sedated intensive care unit (ICU) patients may be inaccurate due to this variability. Trial registration clinicaltrials.gov Nr. NCT00641563. PMID:19228415

  9. The influence of bandage characteristics and inter-individual application variations on underneath bandage pressures.

    PubMed

    Morlock, MM; Nassutt, R; Bonin, V

    1997-04-01

    INTRODUCTION:: Cohesive bandages are applied to the legs of racehorses and horses with limb injuries for protection (prevention of abrasion) and support (reduction of movement at the fetlock joint). The support capacity of all commercially available bandages has been questioned. Consequently, the protection aspect of bandaging and the negative side effects, which can be caused by bandaging (eg pressure induced ischemia with subsequent necrosis), were emphasized. High pressures underneath bandages were shown to cause reduced blood flow. Pressures underneath certain types of bandages were shown to be higher than under others. It is unclear if these differences were due to differences in material characteristics between the bandage types or caused by differences in application by the trainers. The purpose of this study was to determine (a) if differences between different types of bandages are observed if these are applied similarly and (b) if earlier observed differences in pressures underneath bandages are reproducible when wrapped by different trainers. METHODS AND MATERIAL:: (a) A wrapping machine for the application of bandages to an artificial joint (simulating the human knee joint) was designed and built. The machine allows to wrap bandages with adjustable, constant tension under well defined wrapping angles in order to simulate a wrapping technique similar to the wrapping by trainers. The artificial joint is equipped with two pressure sensors (Parotec, Germany). After bandage application, the artificial joint was placed in a specially designed testing machine and cycled through 200 cycles from 0 degrees to 90 degrees of flexion at a frequency of 0.5 Hz. Pressure data were collected at a frequency of 20 Hz. The force required to unwind the bandage from its core was measured with a material testing machine. Five samples each of four different 4" wide cohesive bandages were tested: 'E': high modulus latex, 'V': low mod. latex, 'C': low mod. latex, 'F': medium mod

  10. Inter-Individual and Inter-Strain Variations in Zebrafish Locomotor Ontogeny

    PubMed Central

    Lange, Merlin; Neuzeret, Frederic; Fabreges, Benoit; Froc, Cynthia; Bedu, Sebastien; Bally-Cuif, Laure; Norton, William H. J.

    2013-01-01

    Zebrafish exhibit remarkable alterations in behaviour and morphology as they develop from early larval stages to mature adults. In this study we compare the locomotion parameters of six common zebrafish strains from two different laboratories to determine the stability and repeatability of these behaviours. Our results demonstrate large variability in locomotion and fast swim events between strains and between laboratories across time. These data highlight the necessity for careful, strain-specific controls when analysing locomotor phenotypes and open up the possibility of standardising the quantification of zebrafish behaviour at multiple life stages. PMID:23950910

  11. Assessment of Inter-Individual, Geographic, and Seasonal Variability in Estimated Human Exposure to Fine Particles

    PubMed Central

    Jiao, Wan; Frey, H. Christopher; Cao, Ye

    2012-01-01

    Health effects associated with ambient fine particle (PM2.5) exposure are typically estimated based on concentration-response (C-R) functions using area-wide concentration as an exposure surrogate. Persons 65 and older are particularly susceptible to adverse effects from PM2.5 exposure. Using a stochastic microenvironmental simulation model, distributions of daily PM2.5 exposures were estimated based on ambient concentration, air exchange rate, penetration factor, deposition rate, indoor emission sources, census data, and activity diary data, and compared for selected regions and seasons. Even though the selected subpopulation spends an average of over 20 hours per day indoors, the ratio of daily average estimated exposure to ambient concentration (Ea/C) is approximately 0.5. The daily average Ea/C ratio varies by a factor of 4 to 5 over a 95% frequency range among individuals, primarily from variability in air exchange rates. The mean Ea/C varies by 6 to 36% among selected NC, TX and NYC domains, and 15 to 34% among four seasons, as a result of regional differences in housing stock and seasonal differences in air exchange rates. Variability in Ea/C is a key factor that may help explain heterogeneity in C-R functions across cities and seasons. Priorities for improving exposure estimates are discussed. PMID:23095102

  12. High inter-individual variation in the gestation length of the hedgehog tenrec, Echinops telfairi (Afrotheria).

    PubMed

    Künzle, H; Poulsen Nautrup, C; Schwarzenberger, F

    2007-02-01

    The gestation length (GL) of Tenrecs (Tenrecinae, Afrotheria) is still uncertain. This lack of knowledge also applies to the lesser hedgehog tenrec, Echinops telfairi, the species most commonly bred and maintained in captivity. The animals used in this study were held under controlled conditions (light, temperature and humidity). In order to determine the GL, groups of female tenrecs were subjected to various mating procedures followed by isolation periods of different lengths. A total of n=249 pregnancies were analysed and the number of offspring per litter was 3.29+/-0.09. The length of gestation could be determined in n=199 pregnancies and a mean GL of 67.53+/-0.36 days was calculated. Initial attempts with isolation periods of less than 16 days did not allow to accurately define the GL. Experiments with longer isolation periods and females subjected to only one mating procedure (n=10) revealed a variation in the GLs of 57-79 days. However, in one female a GL of only 50 days was also observed indicating an even greater range in GL variation. There was a statistically significant tendency for shorter GLs in the animals that conceived later in the mating season, but no statistical evidence was found that age, parity or litter size played an essential role in determining the GL. In conclusion, an unexpected high variability in gestation length in E. telfairi was demonstrated although the study animals were kept under controlled environmental conditions. The factors and mechanisms regulating this high intra-species variability in gestation length need further investigations. PMID:16569484

  13. The effects of rearing density on growth, size heterogeneity and inter-individual variation of feed intake in monosex male Nile tilapia Oreochromis niloticus L.

    PubMed

    Azaza, M S; Assad, A; Maghrbi, W; El-Cafsi, M

    2013-11-01

    The growth dispersion of farmed fish is a subject of increasing interest and one of the most important factors in stocking density. On a duration of 60 days, the effect of stocking density on the growth, coefficient of variation and inter-individual variation of feed intake (CVFI) of juvenile Nile tilapia Oreochromis niloticus L. (14.9 ± 1.2 g) were studied in an experimental tank-based flow-through system. Groups of fish were stocked at four stocking densities: 200, 400, 600 and 800 fish/m3, corresponding to a density of ∼3, 6, 9 and 12 kg/m3 and referred to as D1, D2, D3 and D4, respectively. Each treatment was applied to triplicate groups in a completely randomized design. No treatment-related mortality was observed. The fish densities increased throughout the experiment from 3 to 23.5, 6 to 43.6, 9 to 56.6 and 12 to 69 kg/m3. Results show that mass gain and specific growth rate (SGR, %M/day) were negatively correlated with increased stocking density. Groups of the D1 treatment reached a mean final body mass (FBM) of 119.3 g v. 88.9 g for the D4 groups. Feed conversion ratios (FCRs) were 1.38, 1.54, 1.62 and 1.91 at D1, D2, D3 and D4 treatments, respectively. Growth heterogeneity, expressed by the inter-individual variations of fish mass (CVM), was significantly affected by time (P < 0.001), stocking density (P < 0.001) and their interaction (P < 0.05). The difference in CVM was particularly conspicuous towards the end of the experiment and was positively correlated with stocking density. Similarly, radiographic study shows that CVFI was also found to be significantly greater for groups reared at high stocking densities (D3 and D4) than the other treatments (D1 and D2). These differences in both CVM and CVFI related to the stocking density need to be taken into account by husbandry practices to assure the production of more homogeneous fish size. A simple economic analysis indicates a parabolic relationship between profit and density with optimal final

  14. Relating inter-individual differences in verbal creative thinking to cerebral structures: an optimal voxel-based morphometry study.

    PubMed

    Zhu, Feifei; Zhang, Qinglin; Qiu, Jiang

    2013-01-01

    Creativity can be defined the capacity of an individual to produce something original and useful. An important measurable component of creativity is divergent thinking. Despite existing studies on creativity-related cerebral structural basis, no study has used a large sample to investigate the relationship between individual verbal creativity and regional gray matter volumes (GMVs) and white matter volumes (WMVs). In the present work, optimal voxel-based morphometry (VBM) was employed to identify the structure that correlates verbal creativity (measured by the verbal form of Torrance Tests of Creative Thinking) across the brain in young healthy subjects. Verbal creativity was found to be significantly positively correlated with regional GMV in the left inferior frontal gyrus (IFG), which is believed to be responsible for language production and comprehension, new semantic representation, and memory retrieval, and in the right IFG, which may involve inhibitory control and attention switching. A relationship between verbal creativity and regional WMV in the left and right IFG was also observed. Overall, a highly verbal creative individual with superior verbal skills may demonstrate a greater computational efficiency in the brain areas involved in high-level cognitive processes including language production, semantic representation and cognitive control. PMID:24223921

  15. Relating Inter-Individual Differences in Verbal Creative Thinking to Cerebral Structures: An Optimal Voxel-Based Morphometry Study

    PubMed Central

    Zhu, Feifei; Zhang, Qinglin; Qiu, Jiang

    2013-01-01

    Creativity can be defined the capacity of an individual to produce something original and useful. An important measurable component of creativity is divergent thinking. Despite existing studies on creativity-related cerebral structural basis, no study has used a large sample to investigate the relationship between individual verbal creativity and regional gray matter volumes (GMVs) and white matter volumes (WMVs). In the present work, optimal voxel-based morphometry (VBM) was employed to identify the structure that correlates verbal creativity (measured by the verbal form of Torrance Tests of Creative Thinking) across the brain in young healthy subjects. Verbal creativity was found to be significantly positively correlated with regional GMV in the left inferior frontal gyrus (IFG), which is believed to be responsible for language production and comprehension, new semantic representation, and memory retrieval, and in the right IFG, which may involve inhibitory control and attention switching. A relationship between verbal creativity and regional WMV in the left and right IFG was also observed. Overall, a highly verbal creative individual with superior verbal skills may demonstrate a greater computational efficiency in the brain areas involved in high-level cognitive processes including language production, semantic representation and cognitive control. PMID:24223921

  16. The human voice areas: Spatial organization and inter-individual variability in temporal and extra-temporal cortices

    PubMed Central

    Pernet, Cyril R.; McAleer, Phil; Latinus, Marianne; Gorgolewski, Krzysztof J.; Charest, Ian; Bestelmeyer, Patricia E.G.; Watson, Rebecca H.; Fleming, David; Crabbe, Frances; Valdes-Sosa, Mitchell; Belin, Pascal

    2015-01-01

    fMRI studies increasingly examine functions and properties of non-primary areas of human auditory cortex. However there is currently no standardized localization procedure to reliably identify specific areas across individuals such as the standard ‘localizers’ available in the visual domain. Here we present an fMRI ‘voice localizer’ scan allowing rapid and reliable localization of the voice-sensitive ‘temporal voice areas’ (TVA) of human auditory cortex. We describe results obtained using this standardized localizer scan in a large cohort of normal adult subjects. Most participants (94%) showed bilateral patches of significantly greater response to vocal than non-vocal sounds along the superior temporal sulcus/gyrus (STS/STG). Individual activation patterns, although reproducible, showed high inter-individual variability in precise anatomical location. Cluster analysis of individual peaks from the large cohort highlighted three bilateral clusters of voice-sensitivity, or “voice patches” along posterior (TVAp), mid (TVAm) and anterior (TVAa) STS/STG, respectively. A series of extra-temporal areas including bilateral inferior prefrontal cortex and amygdalae showed small, but reliable voice-sensitivity as part of a large-scale cerebral voice network. Stimuli for the voice localizer scan and probabilistic maps in MNI space are available for download. PMID:26116964

  17. The human voice areas: Spatial organization and inter-individual variability in temporal and extra-temporal cortices.

    PubMed

    Pernet, Cyril R; McAleer, Phil; Latinus, Marianne; Gorgolewski, Krzysztof J; Charest, Ian; Bestelmeyer, Patricia E G; Watson, Rebecca H; Fleming, David; Crabbe, Frances; Valdes-Sosa, Mitchell; Belin, Pascal

    2015-10-01

    fMRI studies increasingly examine functions and properties of non-primary areas of human auditory cortex. However there is currently no standardized localization procedure to reliably identify specific areas across individuals such as the standard 'localizers' available in the visual domain. Here we present an fMRI 'voice localizer' scan allowing rapid and reliable localization of the voice-sensitive 'temporal voice areas' (TVA) of human auditory cortex. We describe results obtained using this standardized localizer scan in a large cohort of normal adult subjects. Most participants (94%) showed bilateral patches of significantly greater response to vocal than non-vocal sounds along the superior temporal sulcus/gyrus (STS/STG). Individual activation patterns, although reproducible, showed high inter-individual variability in precise anatomical location. Cluster analysis of individual peaks from the large cohort highlighted three bilateral clusters of voice-sensitivity, or "voice patches" along posterior (TVAp), mid (TVAm) and anterior (TVAa) STS/STG, respectively. A series of extra-temporal areas including bilateral inferior prefrontal cortex and amygdalae showed small, but reliable voice-sensitivity as part of a large-scale cerebral voice network. Stimuli for the voice localizer scan and probabilistic maps in MNI space are available for download. PMID:26116964

  18. Inter-annual and inter-individual variations in survival exhibit strong seasonality in a hibernating rodent.

    PubMed

    Le Cœur, Christie; Chantepie, Stéphane; Pisanu, Benoît; Chapuis, Jean-Louis; Robert, Alexandre

    2016-07-01

    Most research on the demography of wild animal populations has focused on characterizing the variation in the mortality of organisms as a function of intrinsic and environmental characteristics. However, such variation in mortality is difficult to relate to functional life history components (e.g. reproduction, dispersal, hibernation) due to the difficulty in monitoring biological processes at a sufficiently fine timescale. In this study, we used a 10-year individual-based data set with an infra-annual timescale to investigate both intra- and inter-annual survival patterns according to intrinsic and environmental covariates in an introduced population of a small hibernating rodent, the Siberian chipmunk. We compared three distinct periods related to particular life history events: spring reproduction, summer reproduction and hibernation. Our results revealed strong interactions between intrinsic and temporal effects. First, survival of male chipmunks strongly decreases during the reproduction periods, while survival is high and equal between sexes during hibernation. Second, the season of birth affects the survival of juveniles during their first hibernation, which does not have long-lasting consequences at the adult stage. Third, at an inter-annual scale, we found that high food resource availability before hibernation and low chipmunk densities specifically favour subsequent winter survival. Overall, our results confirm that the well-known patterns of yearly and inter-individual variation of mortality observed in animals are themselves strongly variable within a given year, suggesting that they are associated with various functional components of the animals' life history. PMID:26969470

  19. Species interactions differ in their genetic robustness

    DOE PAGESBeta

    Chubiz, Lon M.; Granger, Brian R.; Segre, Daniel; Harcombe, William R.

    2015-04-14

    Conflict and cooperation between bacterial species drive the composition and function of microbial communities. Stability of these emergent properties will be influenced by the degree to which species' interactions are robust to genetic perturbations. We use genome-scale metabolic modeling to computationally analyze the impact of genetic changes when Escherichia coli and Salmonella enterica compete, or cooperate. We systematically knocked out in silico each reaction in the metabolic network of E. coli to construct all 2583 mutant stoichiometric models. Then, using a recently developed multi-scale computational framework, we simulated the growth of each mutant E. coli in the presence of S.more » enterica. The type of interaction between species was set by modulating the initial metabolites present in the environment. We found that the community was most robust to genetic perturbations when the organisms were cooperating. Species ratios were more stable in the cooperative community, and community biomass had equal variance in the two contexts. Additionally, the number of mutations that have a substantial effect is lower when the species cooperate than when they are competing. In contrast, when mutations were added to the S. enterica network the system was more robust when the bacteria were competing. These results highlight the utility of connecting metabolic mechanisms and studies of ecological stability. Cooperation and conflict alter the connection between genetic changes and properties that emerge at higher levels of biological organization.« less

  20. Genetic differences in airway smooth muscle function.

    PubMed

    Martin, James G; Jo, Taisuke

    2008-01-01

    The genetic basis for airway smooth muscle properties is poorly explored. Contraction and relaxation are altered in asthmatic airway smooth muscle, but the basis for the alterations and the role that muscle-specific susceptibility genes may play is largely unexplored. Alterations in the beta-adrenergic receptor, signaling pathways affecting inositol phosphate metabolism, adenylyl and guanylyl cyclase activity, and contractile proteins such as the myosin heavy chain are all suggested by experimental model systems. Significant changes in proliferative and secretory capacities of asthmatic smooth muscle are also demonstrated, but their genetic basis also requires elucidation. Certain asthma-related genes such as ADAM33, although potentially important for smooth muscle function, have been incompletely explored. PMID:18094088

  1. Species interactions differ in their genetic robustness

    SciTech Connect

    Chubiz, Lon M.; Granger, Brian R.; Segre, Daniel; Harcombe, William R.

    2015-04-14

    Conflict and cooperation between bacterial species drive the composition and function of microbial communities. Stability of these emergent properties will be influenced by the degree to which species' interactions are robust to genetic perturbations. We use genome-scale metabolic modeling to computationally analyze the impact of genetic changes when Escherichia coli and Salmonella enterica compete, or cooperate. We systematically knocked out in silico each reaction in the metabolic network of E. coli to construct all 2583 mutant stoichiometric models. Then, using a recently developed multi-scale computational framework, we simulated the growth of each mutant E. coli in the presence of S. enterica. The type of interaction between species was set by modulating the initial metabolites present in the environment. We found that the community was most robust to genetic perturbations when the organisms were cooperating. Species ratios were more stable in the cooperative community, and community biomass had equal variance in the two contexts. Additionally, the number of mutations that have a substantial effect is lower when the species cooperate than when they are competing. In contrast, when mutations were added to the S. enterica network the system was more robust when the bacteria were competing. These results highlight the utility of connecting metabolic mechanisms and studies of ecological stability. Cooperation and conflict alter the connection between genetic changes and properties that emerge at higher levels of biological organization.

  2. Prediction of inter-individual variability on the pharmacokinetics of CYP1A2 substrates in non-smoking healthy volunteers.

    PubMed

    Haraya, Kenta; Kato, Motohiro; Chiba, Koji; Sugiyama, Yuichi

    2016-08-01

    The activity of CYP1A2, a major drug-metabolizing enzyme, is known to be affected by various environmental factors. Our study aimed to predict inter-individual variability of AUC/Dose of CYP1A2 substrates in non-smoking healthy volunteers using the Monte Carlo simulation. Inter-individual variability in hepatic intrinsic clearance of CYP1A2 substrates (CLint,h,1A2) was estimated using dispersion model based on the inter-individual variability (N = 96) of the AUC of caffeine, a major CYP1A2 substrate. The estimated coefficient of variation (CV) of CLint,h,1A2 was 55%, similar to previously reported CLint,h,2D6 (60%) but larger than CLint,h,3A4 (33%). Then, this estimated CV was validated by predicting the CVs of AUC/Dose of tizanidine and phenacetin, which are mainly metabolized by CYP1A2 and have negligible renal clearance. As a result, reported CVs were successfully predicted within 2.5-97.5 percentile range of predicted values. Moreover, CVs for AUC/Dose of the CYP1A2 substrates theophylline and lidocaine, which are affected by other CYPs and renal clearance, were also successfully predicted. The inter-individual variability of AUC/Dose of CYP1A2 substrates was successfully predicted using 55% CV for CLint,h,1A2, and the results, along with those reported by our group for other CYPs, support the prediction of inter-individual variability of pharmacokinetics in the clinical setting. PMID:27318879

  3. Inter-Individual Responses to Experimental Muscle Pain: Baseline Physiological Parameters Do Not Determine Whether Muscle Sympathetic Nerve Activity Increases or Decreases During Pain

    PubMed Central

    Kobuch, Sophie; Fazalbhoy, Azharuddin; Brown, Rachael; Macefield, Vaughan G.

    2015-01-01

    We have previously reported that there are inter-individual differences in the cardiovascular responses to experimental muscle pain, which are consistent over time: intramuscular infusion of hypertonic saline, causing pain lasting ~60 min, increases muscle sympathetic nerve activity (MSNA)—as well as blood pressure and heart rate—in certain subjects, but decrease it in others. Here, we tested the hypothesis that baseline physiological parameters (resting MSNA, heart rate, blood pressure, heart rate variability) determine the cardiovascular responses to long-lasting muscle pain. MSNA was recorded from the common peroneal nerve, together with heart rate and blood pressure, during a 45-min intramuscular infusion of hypertonic saline solution into the tibialis anterior of 50 awake human subjects (25 females and 25 males). Twenty-four subjects showed a sustained increase in mean amplitude of MSNA (160.9 ± 7.3%), while 26 showed a sustained decrease (55.1 ± 3.5%). Between the increasing and decreasing groups there were no differences in baseline MSNA (19.0 ± 1.5 vs. 18.9 ± 1.2 bursts/min), mean BP (88.1 ± 5.2 vs. 88.0 ± 3.8 mmHg), HR (74.7 ± 2.0 vs. 72.8 ± 1.8 beats/min) or heart rate variability (LF/HF 1.8 ± 0.2 vs. 2.2 ± 0.3). Furthermore, neither sex nor body mass index had any effect on whether MSNA increased or decreased during tonic muscle pain. We conclude that the measured baseline physiological parameters cannot account for the divergent sympathetic responses during tonic muscle pain. PMID:26733786

  4. Inter-Individual Responses to Experimental Muscle Pain: Baseline Physiological Parameters Do Not Determine Whether Muscle Sympathetic Nerve Activity Increases or Decreases During Pain.

    PubMed

    Kobuch, Sophie; Fazalbhoy, Azharuddin; Brown, Rachael; Macefield, Vaughan G

    2015-01-01

    We have previously reported that there are inter-individual differences in the cardiovascular responses to experimental muscle pain, which are consistent over time: intramuscular infusion of hypertonic saline, causing pain lasting ~60 min, increases muscle sympathetic nerve activity (MSNA)-as well as blood pressure and heart rate-in certain subjects, but decrease it in others. Here, we tested the hypothesis that baseline physiological parameters (resting MSNA, heart rate, blood pressure, heart rate variability) determine the cardiovascular responses to long-lasting muscle pain. MSNA was recorded from the common peroneal nerve, together with heart rate and blood pressure, during a 45-min intramuscular infusion of hypertonic saline solution into the tibialis anterior of 50 awake human subjects (25 females and 25 males). Twenty-four subjects showed a sustained increase in mean amplitude of MSNA (160.9 ± 7.3%), while 26 showed a sustained decrease (55.1 ± 3.5%). Between the increasing and decreasing groups there were no differences in baseline MSNA (19.0 ± 1.5 vs. 18.9 ± 1.2 bursts/min), mean BP (88.1 ± 5.2 vs. 88.0 ± 3.8 mmHg), HR (74.7 ± 2.0 vs. 72.8 ± 1.8 beats/min) or heart rate variability (LF/HF 1.8 ± 0.2 vs. 2.2 ± 0.3). Furthermore, neither sex nor body mass index had any effect on whether MSNA increased or decreased during tonic muscle pain. We conclude that the measured baseline physiological parameters cannot account for the divergent sympathetic responses during tonic muscle pain. PMID:26733786

  5. Mate choice for neutral and MHC genetic characteristics in Alpine marmots: different targets in different contexts?

    PubMed

    Ferrandiz-Rovira, Mariona; Allainé, Dominique; Callait-Cardinal, Marie-Pierre; Cohas, Aurélie

    2016-07-01

    Sexual selection through female mate choice for genetic characteristics has been suggested to be an important evolutionary force maintaining genetic variation in animal populations. However, the genetic targets of female mate choice are not clearly identified and whether female mate choice is based on neutral genetic characteristics or on particular functional loci remains an open question. Here, we investigated the genetic targets of female mate choice in Alpine marmots (Marmota marmota), a socially monogamous mammal where extra-pair paternity (EPP) occurs. We used 16 microsatellites to describe neutral genetic characteristics and two MHC loci belonging to MHC class I and II as functional genetic characteristics. Our results reveal that (1) neutral and MHC genetic characteristics convey different information in this species, (2) social pairs show a higher MHC class II dissimilarity than expected under random mate choice, and (3) the occurrence of EPP increases when social pairs present a high neutral genetic similarity or dissimilarity but also when they present low MHC class II dissimilarity. Thus, female mate choice is based on both neutral and MHC genetic characteristics, and the genetic characteristics targeted seem to be context dependent (i.e., the genes involved in social mate choice and genetic mate choice differ). We emphasize the need for empirical studies of mate choice in the wild using both neutral and MHC genetic characteristics because whether neutral and functional genetic characteristics convey similar information is not universal. PMID:27386072

  6. Race, Intelligence and Genetics: The Differences Are Real

    ERIC Educational Resources Information Center

    Jensen, Arthur

    1973-01-01

    The author reexamines the controversy surrounding his genetic hypothesis in an attempt to clarify his contention that differences in IQ scores between blacks and whites may be attributable as much to heredity as environment. (EH)

  7. Translating Population Difference: The Use and Re-Use of Genetic Ancestry in Brazilian Cancer Genetics.

    PubMed

    Gibbon, Sahra

    2016-01-01

    In the past ten years, there has been an expansion of scientific interest in population genetics linked to both understanding histories of human migration and the way that population difference and diversity may account for and/or be implicated in health and disease. In this article, I examine how particular aspects of a globalizing research agenda related to population differences and genetic ancestry are taken up in locally variant ways in the nascent field of Brazilian cancer genetics. Drawing on a broad range of ethnographic data from clinical and nonclinical contexts in the south of Brazil, I examine the ambiguities that attention to genetic ancestry generates, so revealing the disjunctured and diverse ways a global research agenda increasingly orientated to questions of population difference and genetic ancestry is being used and reused. PMID:26452039

  8. Translating Population Difference: The Use and Re-Use of Genetic Ancestry in Brazilian Cancer Genetics

    PubMed Central

    Gibbon, Sahra

    2016-01-01

    ABSTRACT In the past ten years, there has been an expansion of scientific interest in population genetics linked to both understanding histories of human migration and the way that population difference and diversity may account for and/or be implicated in health and disease. In this article, I examine how particular aspects of a globalizing research agenda related to population differences and genetic ancestry are taken up in locally variant ways in the nascent field of Brazilian cancer genetics. Drawing on a broad range of ethnographic data from clinical and nonclinical contexts in the south of Brazil, I examine the ambiguities that attention to genetic ancestry generates, so revealing the disjunctured and diverse ways a global research agenda increasingly orientated to questions of population difference and genetic ancestry is being used and reused. PMID:26452039

  9. Genetic and environmental influences on human behavioral differences.

    PubMed

    McGue, M; Bouchard, T J

    1998-01-01

    Human behavioral genetic research aimed at characterizing the existence and nature of genetic and environmental influences on individual differences in cognitive ability, personality and interests, and psychopathology is reviewed. Twin and adoption studies indicate that most behavioral characteristics are heritable. Nonetheless, efforts to identify the genes influencing behavior have produced a limited number of confirmed linkages or associations. Behavioral genetic research also documents the importance of environmental factors, but contrary to the expectations of many behavioral scientists, the relevant environmental factors appear to be those that are not shared by reared together relatives. The observation of genotype-environment correlational processes and the hypothesized existence of genotype-environment interaction effects serve to distinguish behavioral traits from the medical and physiological phenotypes studied by human geneticists. Behavioral genetic research supports the heritability, not the genetic determination, of behavior. PMID:9530489

  10. Visualising difference, similarity and belonging in paediatric genetics

    PubMed Central

    McLaughlin, Janice; Clavering, Emma K

    2012-01-01

    Paediatric genetics is increasingly playing a role in explorations of why a child may not be reaching developmental milestones, while experiencing various health concerns and displaying unusual physical characteristics. The diagnostic processes include close analyses of a child’s body in order to identify ‘clues’ to possible genetic variation. When the genetic variation identified is new and complex there is significant uncertainty about what relationship that variation has to childhood development and what it will mean for a child’s future. This paper, drawing from an ethnographic study of a genetics clinic, explores what versions of childhood difference and normality are produced by genetic explorations marked by uncertainty. The focus is on the significance of visual dynamics within the consultation, in family stories or photographs, and in the images found on websites which catalogue genetic syndromes. Our argument is that inside and outside the clinic the visual interpretations create understandings of the child that at times position him or her as ‘other’, while at other times recognise the child as normal and ‘one of us’. The uncertainty embedded in identifying rare genetic variations enables multiple interpretations to emerge which do not ‘fix’ the child into the category of the ‘genetically other’. PMID:22050692

  11. Environmental and genetic perturbations reveal different networks of metabolic regulation

    PubMed Central

    Greenberg, Anthony J; Hackett, Sean R; Harshman, Lawrence G; Clark, Andrew G

    2011-01-01

    Progress in systems biology depends on accurate descriptions of biological networks. Connections in a regulatory network are identified as correlations of gene expression across a set of environmental or genetic perturbations. To use this information to predict system behavior, we must test how the nature of perturbations affects topologies of networks they reveal. To probe this question, we focused on metabolism of Drosophila melanogaster. Our source of perturbations is a set of crosses among 92 wild-derived lines from five populations, replicated in a manner permitting separate assessment of the effects of genetic variation and environmental fluctuation. We directly assayed activities of enzymes and levels of metabolites. Using a multivariate Bayesian model, we estimated covariance among metabolic parameters and built fine-grained probabilistic models of network topology. The environmental and genetic co-regulation networks are substantially the same among five populations. However, genetic and environmental perturbations reveal qualitative differences in metabolic regulation, suggesting that environmental shifts, such as diet modifications, produce different systemic effects than genetic changes, even if the primary targets are the same. PMID:22186737

  12. Trace/minor element:calcium ratios in cultured benthic foraminifera. Part I: Inter-species and inter-individual variability

    NASA Astrophysics Data System (ADS)

    Hintz, Christopher J.; Shaw, Timothy J.; Chandler, G. Thomas; Bernhard, Joan M.; McCorkle, Daniel C.; Blanks, Jessica K.

    2006-04-01

    Trace/minor element signatures ( DCd, DBa, DMg, and DSr) were measured in the tests (shells) of benthic foraminifera cultured in a trace-metal-concentration-controlled system. The culture system was constructed of inert materials and designed to limit microhabitat effects. This system ensured that variation observed in cultured foraminiferal element:calcium (TE/Ca) signatures was due to biologically mediated (vital) effects only. Two species, Bulimina aculeata and Rosalina vilardeboana, reproduced prolifically during two 4-to-8-month culture periods. In every case (i.e., for both species and each element), the inter-individual variability was larger than the analytical precision. Mean (±1 standard deviation) DE signatures for B. aculeata were: DCd: 1.5 ± 0.4, DBa × 10: 2.1 ± 0.7, DMg × 1000: 0.62 ± 0.15, and DSr × 10: 1.5 ± 0.1. Cultured B. aculeata DMg, calibrated from culture and core-top (live) field specimens, predicted temperatures within ±2.0 °C. The observed inter-individual variability from culture specimens was as large or larger than comparable results from core-top investigations. R. vilardeboana DCd signatures were significantly lower, while DBa, DMg, and DSr signatures were significantly higher than B. aculeata values. Since our culture system minimizes microhabitat variability, the variation in measured TE/Ca ratios suggests that biological processes are a significant factor in inter-individual and inter-species variability. Comparison of cultured and field-collected foraminiferal DBa signatures supports previous findings that pore-water chemistry is a major environmental influence on foraminiferal test chemistry.

  13. Genetic and environmental stability differs in reactive and proactive aggression.

    PubMed

    Tuvblad, Catherine; Raine, Adrian; Zheng, Mo; Baker, Laura A

    2009-01-01

    The aim of this study was to examine stability and change in genetic and environmental influences on reactive (impulsive and affective) and proactive (planned and instrumental) aggression from childhood to early adolescence. The sample was drawn from an ongoing longitudinal twin study of risk factors for antisocial behavior at the University of Southern California (USC). The twins were measured on two occasions: ages 9-10 years (N=1,241) and 11-14 years (N=874). Reactive and proactive aggressive behaviors were rated by parents. The stability in reactive aggression was due to genetic and nonshared environmental influences, whereas the continuity in proactive aggression was primarily genetically mediated. Change in both reactive and proactive aggression between the two occasions was mainly explained by nonshared environmental influences, although some evidence for new genetic variance at the second occasion was found for both forms of aggression. These results suggest that proactive and reactive aggression differ in their genetic and environmental stability, and provide further evidence for some distinction between reactive and proactive forms of aggression. PMID:19688841

  14. Differences between adults and children: genetics and beyond.

    PubMed

    Billiet, Thomas; Vermeire, Severine

    2015-02-01

    Clinical observations and epidemiological studies have highlighted some important differences in disease course and phenotypes between pediatric inflammatory bowel disease (IBD) and adult-onset IBD. Also from a therapeutic angle, the approach to young-onset IBD is different with a more rapid introduction of azathioprine and a high threshold for long and systemic steroid use, which may affect bone mineral density and growth. The observed clinical differences have been an area of scientific research and genetic studies have been the focus of attention. Specific candidate gene studies as well as genome-wide association studies have been performed in pediatric IBD. With the exception of very early-onset IBD occurring before the age of 2 years; no overt differences in genetic susceptibility have been identified. In contrast, very early-onset IBD seems in particular to be a genetic disease with defects in the IL10 signaling pathway being the principal example. This review aims to answer some straightforward questions arising in this topic by giving concise information. PMID:25134842

  15. Genetic Structure in Dwarf Bamboo (Bashania fangiana) Clonal Populations with Different Genet Ages

    PubMed Central

    Ma, Qing-qing; Song, Hui-xing; Zhou, Shi-qiang; Yang, Wan-qin; Li, De-sheng; Chen, Jin-song

    2013-01-01

    Amplified fragment length polymorphism (AFLP) fingerprints were used to reveal genotypic diversity of dwarf bamboo (Bashania fangiana) clonal populations with two different genet ages (≤30 years versus >70 years) at Wolong National Natural Reserve, Sichuan province, China. We generated AFLP fingerprints for 96 leaf samples, collected at 30 m intervals in the two populations, using ten selective primer pairs. A total of 92 genotypes were identified from the both populations. The mean proportion of distinguishable genotypes (G/N) was 0.9583 (0.9375 to 0.9792) and Simpson's index of diversity (D) was 0.9982 (0.9973 to 0.9991). So, two B. fangiana populations were multiclonal and highly diverse. The largest single clone may occur over a distance of about 30 m. Our results demonstrated that the genotypic diversity and genet density of B. fangiana clonal population did not change significantly (47 versus 45) with genet aging and low partitioned genetic differentiation was between the two populations (Gst = 0.0571). The analysis of molecular variance consistently showed that a large proportion of the genetic variation (87.79%) existed among the individuals within populations, whereas only 12.21% were found among populations. In addition, the high level of genotypic diversity in the two populations implies that the further works were needed to investigate the reasons for the poor seed set in B. fangiana after flowering. PMID:24244360

  16. Genetic differences between paediatric and adult Burkitt lymphomas.

    PubMed

    Havelange, Violaine; Pepermans, Xavier; Ameye, Geneviève; Théate, Ivan; Callet-Bauchu, Evelyne; Barin, Carole; Penther, Dominique; Lippert, Eric; Michaux, Lucienne; Mugneret, Francine; Dastugue, Nicole; Raphaël, Martine; Vikkula, Miikka; Poirel, Hélène A

    2016-04-01

    Dysregulation of MYC is the genetic hallmark of Burkitt lymphoma (BL) but it is encountered in other aggressive mature B-cell lymphomas. MYC dysregulation needs other cooperating events for BL development. We aimed to characterize these events and assess the differences between adult and paediatric BLs that may explain the different outcomes in these two populations. We analysed patterns of genetic aberrations in a series of 24 BLs: 11 adults and 13 children. We looked for genomic imbalances (copy number variations), copy-neutral loss of heterozygosity (CN-LOH) and mutations in TP53, CDKN2A, ID3 (exon 1), TCF3 (exon17) and CCND3 (exon 6). Young patients displayed more frequent 13q31.3q32.1 amplification, 7q32q36 gain and 5q23.3 CN-LOH, while 17p13 and 18q21.3 CN-LOH were only detected in adult BLs. ID3 mutations were present in all adult samples, but only in 42% of childhood cases. CCND3 and ID3 double-hit mutations, as well as 18q21 CN-LOH, seemed to be associated with poorer outcome. For the first time, we report different genetic anomalies between adult and paediatric BLs, suggesting age-related heterogeneity in Burkitt lymphomagenesis. This may explain the poorer prognosis of adult BLs. Additional studies are needed to confirm these results in the setting of clinical trials. PMID:26887776

  17. The genetics of sex differences in brain and behavior.

    PubMed

    Ngun, Tuck C; Ghahramani, Negar; Sánchez, Francisco J; Bocklandt, Sven; Vilain, Eric

    2011-04-01

    Biological differences between men and women contribute to many sex-specific illnesses and disorders. Historically, it was argued that such differences were largely, if not exclusively, due to gonadal hormone secretions. However, emerging research has shown that some differences are mediated by mechanisms other than the action of these hormone secretions and in particular by products of genes located on the X and Y chromosomes, which we refer to as direct genetic effects. This paper reviews the evidence for direct genetic effects in behavioral and brain sex differences. We highlight the 'four core genotypes' model and sex differences in the midbrain dopaminergic system, specifically focusing on the role of Sry. We also discuss novel research being done on unique populations including people attracted to the same sex and people with a cross-gender identity. As science continues to advance our understanding of biological sex differences, a new field is emerging that is aimed at better addressing the needs of both sexes: gender-based biology and medicine. Ultimately, the study of the biological basis for sex differences will improve healthcare for both men and women. PMID:20951723

  18. The Genetics of Sex Differences in Brain and Behavior

    PubMed Central

    Ngun, Tuck C; Ghahramani, Negar; Sánchez, Francisco J.; Bocklandt, Sven; Vilain, Eric

    2010-01-01

    Biological differences between men and women contribute to many sex-specific illnesses and disorders. Historically, it was argued that such differences were largely, if not exclusively, due to gonadal hormone secretions. However, emerging research has shown that some differences are mediated by mechanisms other than the action of these hormone secretions and in particular by products of genes located on the X and Y chromosomes, which we refer to as direct genetic effects. This paper reviews the evidence for direct genetic effects in behavioral and brain sex differences. We highlight the `four core genotypes' model and sex differences in the midbrain dopaminergic system, specifically focusing on the role of Sry. We also discuss novel research being done on unique populations including people attracted to the same sex and people with a cross-gender identity. As science continues to advance our understanding of biological sex differences, a new field is emerging that is aimed at better addressing the needs of both sexes: gender-based biology and medicine. Ultimately, the study of the biological basis for sex differences will improve healthcare for both men and women. PMID:20951723

  19. Both genetic and dietary factors underlie individual differences in DNA damage levels and DNA repair capacity.

    PubMed

    Slyskova, Jana; Lorenzo, Yolanda; Karlsen, Anette; Carlsen, Monica H; Novosadova, Vendula; Blomhoff, Rune; Vodicka, Pavel; Collins, Andrew R

    2014-04-01

    The interplay between dietary habits and individual genetic make-up is assumed to influence risk of cancer, via modulation of DNA integrity. Our aim was to characterize internal and external factors that underlie inter-individual variability in DNA damage and repair and to identify dietary habits beneficial for maintaining DNA integrity. Habitual diet was estimated in 340 healthy individuals using a food frequency questionnaire and biomarkers of antioxidant status were quantified in fasting blood samples. Markers of DNA integrity were represented by DNA strand breaks, oxidized purines, oxidized pyrimidines and a sum of all three as total DNA damage. DNA repair was characterized by genetic variants and functional activities of base and nucleotide excision repair pathways. Sex, fruit-based food consumption and XPG genotype were factors significantly associated with the level of DNA damage. DNA damage was higher in women (p=0.035). Fruit consumption was negatively associated with the number of all measured DNA lesions, and this effect was mediated mostly by β-cryptoxanthin and β-tocopherol (p<0.05). XPG 1104His homozygotes appeared more vulnerable to DNA damage accumulation (p=0.001). Sex and individual antioxidants were also associated with DNA repair capacity; both the base and nucleotide excision repairs were lower in women and the latter increased with higher plasma levels of ascorbic acid and α-carotene (p<0.05). We have determined genetic and dietary factors that modulate DNA integrity. We propose that the positive health effect of fruit intake is partially mediated via DNA damage suppression and a simultaneous increase in DNA repair capacity. PMID:24674629

  20. Heterogeneity in Genetic Admixture across Different Regions of Argentina

    PubMed Central

    Avena, Sergio; Via, Marc; Ziv, Elad; Pérez-Stable, Eliseo J.; Gignoux, Christopher R.; Dejean, Cristina; Huntsman, Scott; Torres-Mejía, Gabriela; Dutil, Julie; Matta, Jaime L.; Beckman, Kenneth; Burchard, Esteban González; Parolin, María Laura; Goicoechea, Alicia; Acreche, Noemí; Boquet, Mariel; Ríos Part, María Del Carmen; Fernández, Vanesa; Rey, Jorge; Stern, Mariana C.; Carnese, Raúl F.; Fejerman, Laura

    2012-01-01

    The population of Argentina is the result of the intermixing between several groups, including Indigenous American, European and African populations. Despite the commonly held idea that the population of Argentina is of mostly European origin, multiple studies have shown that this process of admixture had an impact in the entire Argentine population. In the present study we characterized the distribution of Indigenous American, European and African ancestry among individuals from different regions of Argentina and evaluated the level of discrepancy between self-reported grandparental origin and genetic ancestry estimates. A set of 99 autosomal ancestry informative markers (AIMs) was genotyped in a sample of 441 Argentine individuals to estimate genetic ancestry. We used non-parametric tests to evaluate statistical significance. The average ancestry for the Argentine sample overall was 65% European (95%CI: 63–68%), 31% Indigenous American (28–33%) and 4% African (3–4%). We observed statistically significant differences in European ancestry across Argentine regions [Buenos Aires province (BA) 76%, 95%CI: 73–79%; Northeast (NEA) 54%, 95%CI: 49–58%; Northwest (NWA) 33%, 95%CI: 21–41%; South 54%, 95%CI: 49–59%; p<0.0001] as well as between the capital and immediate suburbs of Buenos Aires city compared to more distant suburbs [80% (95%CI: 75–86%) versus 68% (95%CI: 58–77%), p = 0.01]. European ancestry among individuals that declared all grandparents born in Europe was 91% (95%CI: 88–94%) compared to 54% (95%CI: 51–57%) among those with no European grandparents (p<0.001). Our results demonstrate the range of variation in genetic ancestry among Argentine individuals from different regions in the country, highlighting the importance of taking this variation into account in genetic association and admixture mapping studies in this population. PMID:22506044

  1. Heterogeneity in genetic admixture across different regions of Argentina.

    PubMed

    Avena, Sergio; Via, Marc; Ziv, Elad; Pérez-Stable, Eliseo J; Gignoux, Christopher R; Dejean, Cristina; Huntsman, Scott; Torres-Mejía, Gabriela; Dutil, Julie; Matta, Jaime L; Beckman, Kenneth; Burchard, Esteban González; Parolin, María Laura; Goicoechea, Alicia; Acreche, Noemí; Boquet, Mariel; Ríos Part, María Del Carmen; Fernández, Vanesa; Rey, Jorge; Stern, Mariana C; Carnese, Raúl F; Fejerman, Laura

    2012-01-01

    The population of Argentina is the result of the intermixing between several groups, including Indigenous American, European and African populations. Despite the commonly held idea that the population of Argentina is of mostly European origin, multiple studies have shown that this process of admixture had an impact in the entire Argentine population. In the present study we characterized the distribution of Indigenous American, European and African ancestry among individuals from different regions of Argentina and evaluated the level of discrepancy between self-reported grandparental origin and genetic ancestry estimates. A set of 99 autosomal ancestry informative markers (AIMs) was genotyped in a sample of 441 Argentine individuals to estimate genetic ancestry. We used non-parametric tests to evaluate statistical significance. The average ancestry for the Argentine sample overall was 65% European (95%CI: 63-68%), 31% Indigenous American (28-33%) and 4% African (3-4%). We observed statistically significant differences in European ancestry across Argentine regions [Buenos Aires province (BA) 76%, 95%CI: 73-79%; Northeast (NEA) 54%, 95%CI: 49-58%; Northwest (NWA) 33%, 95%CI: 21-41%; South 54%, 95%CI: 49-59%; p<0.0001] as well as between the capital and immediate suburbs of Buenos Aires city compared to more distant suburbs [80% (95%CI: 75-86%) versus 68% (95%CI: 58-77%), p = 0.01]. European ancestry among individuals that declared all grandparents born in Europe was 91% (95%CI: 88-94%) compared to 54% (95%CI: 51-57%) among those with no European grandparents (p<0.001). Our results demonstrate the range of variation in genetic ancestry among Argentine individuals from different regions in the country, highlighting the importance of taking this variation into account in genetic association and admixture mapping studies in this population. PMID:22506044

  2. Genetic differences affecting the potency of stereoisomers of halothane.

    PubMed Central

    Sedensky, M M; Cascorbi, H F; Meinwald, J; Radford, P; Morgan, P G

    1994-01-01

    The mechanism of action of volatile anesthetics is the subject of some debate. Much of the controversy has centered on whether the site of such actions is purely lipid in nature or may contain a protein target. This report studies the interaction of stereoisomers of halothane on the wild type and on a variety of genetic mutants of Caenorhabditis elegans. The mutants studied have previously been shown to have altered sensitivities to volatile anesthetics. In one mutant, fc34, (R)-halothane [the (+) isomer] was 3 times more potent than its S (-) isomer. Other mutants and wild-type animals displayed more modest differences in sensitivity to the enantiomers. The results indicate that a genetic pathway exists in C. elegans controlling sensitivity to halothane and that both lipid and protein targets may mediate halothane's effects. PMID:7937836

  3. Cognitive reserve impacts on inter-individual variability in resting-state cerebral metabolism in normal aging.

    PubMed

    Bastin, Christine; Yakushev, Igor; Bahri, Mohamed Ali; Fellgiebel, Andreas; Eustache, Francis; Landeau, Brigitte; Scheurich, Armin; Feyers, Dorothée; Collette, Fabienne; Chételat, Gael; Salmon, Eric

    2012-11-01

    There is a great deal of heterogeneity in the impact of aging on cognition and cerebral functioning. One potential factor contributing to individual differences among the elderly is the cognitive reserve, which designates the partial protection from the deleterious effects of aging that lifetime experience provides. Neuroimaging studies examining task-related activation in elderly people suggested that cognitive reserve takes the form of more efficient use of brain networks and/or greater ability to recruit alternative networks to compensate for age-related cerebral changes. In this exploratory multi-center study, we examined the relationships between cognitive reserve, as measured by education and verbal intelligence, and cerebral metabolism at rest (FDG-PET) in a sample of 74 healthy older participants. Higher degree of education and verbal intelligence was associated with less metabolic activity in the right posterior temporoparietal cortex and the left anterior intraparietal sulcus. Functional connectivity analyses of resting-state fMRI images in a subset of 41 participants indicated that these regions belong to the default mode network and the dorsal attention network respectively. Lower metabolism in the temporoparietal cortex was also associated with better memory abilities. The findings provide evidence for an inverse relationship between cognitive reserve and resting-state activity in key regions of two functional networks respectively involved in internal mentation and goal-directed attention. PMID:22796505

  4. Whisker isotopic signature depicts migration patterns and multi-year intra- and inter-individual foraging strategies in fur seals

    PubMed Central

    Cherel, Y.; Kernaléguen, L.; Richard, P.; Guinet, C.

    2009-01-01

    The movement and dietary history of individuals can be studied using stable isotope records in archival keratinous tissues. Here, we present a chronology of temporally fine-scale data on the trophic niche of otariid seals by measuring the isotopic signature of serially sampled whiskers. Whiskers of male Antarctic fur seals breeding at the Crozet Islands showed synchronous and regular oscillations in both their δ13C and δ15N values that are likely to represent their annual migrations over the long term (mean 4.8 years). At the population level, male Antarctic fur seals showed substantial variation in both δ13C and δ15N values, occupying nearly all the ‘isotopic space’ created by the diversity of potential oceanic habitats (from high Antarctica to the subtropics) and prey (from Antarctic krill to subantarctic and subtropical mesopelagic fishes). At the individual level, whisker isotopic signatures depict a large diversity of foraging strategies. Some seals remained in either subantarctic or Antarctic waters, while the migratory cycle of most animals encompassed a wide latitudinal gradient where they fed on different prey. The isotopic signature of whiskers, therefore, revealed new multi-year foraging strategies of male Antarctic fur seals and is a powerful tool for investigating the ecological niche during cryptic stages of mammals' life. PMID:19793740

  5. Inter-individual responses to experimental muscle pain: Baseline anxiety ratings and attitudes to pain do not determine the direction of the sympathetic response to tonic muscle pain in humans.

    PubMed

    Kobuch, Sophie; Fazalbhoy, Azharuddin; Brown, Rachael; Macefield, Vaughan G

    2016-06-01

    We have recently shown that intramuscular infusion of hypertonic saline, causing pain lasting ~60min, increases muscle sympathetic nerve activity (MSNA) in one group of subjects, yet decreases it in another. Across subjects these divergent sympathetic responses to long-lasting muscle pain are consistent over time and cannot be foreseen on the basis of baseline MSNA, blood pressure, heart rate or sex. We predicted that differences in anxiety or attitudes to pain may account for these differences. Psychometric measures were assessed prior to the induction of pain using the State and Trait Anxiety Inventory (STAI), Pain Vigilance and Awareness Questionnaire (PVAQ), Pain Anxiety Symptoms Scale (PASS) and Pain Catastrophising Scale (PCS); PCS was also administered after the experiment. MSNA was recorded from the common peroneal nerve, before and during a 45-minute intramuscular infusion of hypertonic saline solution into the tibialis anterior muscle of 66 awake human subjects. Forty-one subjects showed an increase in mean burst amplitude of MSNA (172.8±10.6%) while 25 showed a decrease (69.9±3.8%). None of the measured psychological parameters showed significant differences between the increasing and the decreasing groups. We conclude that inter-individual anxiety or pain attitudes do not determine whether MSNA increases or decreases during long-lasting experimental muscle pain in healthy human subjects. PMID:27106401

  6. Genetic Predictors of Response to Different Medical Therapies in Acromegaly.

    PubMed

    Ramos-Leví, Ana M; Bernabeu, Ignacio; Sampedro-Núñez, Miguel; Marazuela, Mónica

    2016-01-01

    In the era of predictive medicine, management of diseases is evolving into a more personal and individualized approach, as more data are available regarding clinical, biochemical, radiological, molecular, histopathological, and genetic aspects. In the particular setting of acromegaly, which is a rare, chronic, debilitating, and disfiguring disease, an optimized approach deems even more necessary, especially because of an associated increased morbidity and mortality, the impact on patients' quality of life, and the increased cost of frequently necessary life-long treatments. In this paper, we review the available studies that address potential genetic influences on acromegaly, their role in the outcome, and response to treatments, as well as their contribution to the risk of developing side effects. We focus mainly on pharmacogenetic factors involved during treatment with dopamine agonists, somatostatin analogs, and pegvisomant. Specifically, mutations in dopamine receptors, somatostatin receptors, growth hormone receptors, and metabolic pathways involved in growth hormone action; polymorphisms in the insulin-like growth factor and the insulin-like growth factor binding proteins; and polymorphisms in other genes that may determine differences in the frequency of developing adverse events. PMID:26940388

  7. Differences in salinity tolerance of genetically distinct Phragmites australis clones

    PubMed Central

    Achenbach, Luciana; Eller, Franziska; Nguyen, Loc Xuan; Brix, Hans

    2013-01-01

    Different clones of the wetland grass Phragmites australis differ in their morphology and physiology, and hence in their ability to cope with environmental stress. We analysed the responses of 15 P. australis clones with distinct ploidy levels (PLs) (4n, 6n, 8n, 10n, 12n) and geographic origins (Romania, Russia, Japan, Czech Republic, Australia) to step-wise increased salinity (8, 16, 24, 32, 40, 56 and 72 ppt). Shoot elongation rate, photosynthesis and plant part-specific ion accumulation were studied in order to assess if traits associated with salinity tolerance can be related to the genetic background and the geographic origin of the clones. Salt stress affected all clones, but at different rates. The maximum height was reduced from 1860 mm in control plants to 660 mm at 40 ppt salinity. The shoot elongation rate of salt-exposed plants varied significantly between clones until 40 ppt salinity. The light-saturated photosynthesis rate (Pmax) was stimulated by a salinity of 8 ppt, but decreased significantly at higher salinities. The stomatal conductance (gs) and the transpiration rate (E) decreased with increasing salinity. Only three clones survived at 72 ppt salinity, although their rates of photosynthesis were strongly inhibited. The roots and basal leaves of the salt-exposed plants accumulated high concentrations of water-extractable Na+ (1646 and 1004 µmol g−1 dry mass (DM), respectively) and Cl− (1876 and 1400 µmol g−1 DM, respectively). The concentrations of water-extractable Mg2+ and Ca2+ were reduced in salt-exposed plants compared with controls. The variation of all the measured parameters was higher among clones than among PLs. We conclude that the salinity tolerance of distinct P. australis clones varies widely and can be partially attributed to their longitudinal geographic origin, but not to PL. Further investigation will help in improving the understanding of this species' salt tolerance mechanisms and their connection to genetic factors.

  8. Is there a genetic contribution to cultural differences? Collectivism, individualism and genetic markers of social sensitivity

    PubMed Central

    Lieberman, Matthew D.

    2010-01-01

    Genes and culture are often thought of as opposite ends of the nature–nurture spectrum, but here we examine possible interactions. Genetic association studies suggest that variation within the genes of central neurotransmitter systems, particularly the serotonin (5-HTTLPR, MAOA-uVNTR) and opioid (OPRM1 A118G), are associated with individual differences in social sensitivity, which reflects the degree of emotional responsivity to social events and experiences. Here, we review recent work that has demonstrated a robust cross-national correlation between the relative frequency of variants in these genes and the relative degree of individualism–collectivism in each population, suggesting that collectivism may have developed and persisted in populations with a high proportion of putative social sensitivity alleles because it was more compatible with such groups. Consistent with this notion, there was a correlation between the relative proportion of these alleles and lifetime prevalence of major depression across nations. The relationship between allele frequency and depression was partially mediated by individualism–collectivism, suggesting that reduced levels of depression in populations with a high proportion of social sensitivity alleles is due to greater collectivism. These results indicate that genetic variation may interact with ecological and social factors to influence psychocultural differences. PMID:20592043

  9. Roles of inter-individual differences and intra-individual acute elevations in early smoking lapse in people with posttraumatic stress disorder.

    PubMed

    Dedert, Eric A; Hicks, Terrell A; Dennis, Paul A; Calhoun, Patrick S; Beckham, Jean C

    2016-09-01

    Existing models of the role of posttraumatic stress disorder (PTSD) symptoms and smoking have almost exclusively examined mean symptom levels, rather than the acute elevations that might trigger smoking lapse immediately or increase risk of a smoking lapse in the next few hours. We examined ecological momentary assessments (EMA) of PTSD symptom clusters and smoking in the first week of a quit attempt in 52 people with PTSD. In multilevel models including PTSD symptom means, acute elevations, and lagged acute elevations together as simultaneous predictors of odds of smoking in the same models, pre-quit smoking occasions were significantly related to acute elevations in symptoms, including PTSD totals (OR=1.20; 95% CI, 1.10 to 1.31), PTSD re-experiencing symptoms (OR=1.16; 95% CI, 1.06 to 1.27), PTSD avoidance symptoms (OR=1.20; 95% CI, 1.10 to 1.31), PTSD numbing symptoms (OR=1.14; 95% CI, 1.04 to 1.24), and PTSD hyperarousal symptoms (OR=1.20; 95% CI, 1.09 to 1.31). In contrast, post-quit smoking was related to lagged acute elevations in PTSD re-experiencing (OR=1.24, 95% CI, 1.03 to 1.50) avoidance (OR=1.27, 95% CI, 1.05 to 1.53), and numbing symptoms (OR=1.24, 95% CI, 1.02 to 1.51). During a quit attempt, individuals with PTSD delayed smoking in response to acute elevations in PTSD re-experiencing and Avoidance. This period presents an opportunity to use mobile health interventions to prevent smoking lapse and to use coping skills acquired in trauma-focused therapy to respond to acute PTSD symptom elevation. PMID:27155244

  10. Living in a Genetic World: How Learning About Interethnic Genetic Similarities and Differences Affects Peace and Conflict.

    PubMed

    Kimel, Sasha Y; Huesmann, Rowell; Kunst, Jonas R; Halperin, Eran

    2016-05-01

    Information about the degree of one's genetic overlap with ethnic outgroups has been emphasized in genocides, is frequently learned about through media reporting, and is increasingly being accessed via personal genetic testing services. However, the consequence of learning about whether your own ethnic group is either genetically related to or genetically distinct from a disliked ethnic group remains unknown. Across four experiments, using diverse samples, measures and contexts, we demonstrate that altering perceptions of genetic overlap between groups in conflict--in this case Arabs and Jews--impacts factors that are directly related to interethnic hostility (e.g., aggressive behaviors, support of conflict-related policies). Our findings indicate that learning about the genetic difference between oneself and an ethnic outgroup may contribute to the promotion of violence, whereas learning about the similarities may be a vital step toward fostering peace in some contexts. Possible interventions and implications are discussed. PMID:27029578

  11. Linking unfounded beliefs to genetic dopamine availability

    PubMed Central

    Schmack, Katharina; Rössler, Hannes; Sekutowicz, Maria; Brandl, Eva J.; Müller, Daniel J.; Petrovic, Predrag; Sterzer, Philipp

    2015-01-01

    Unfounded convictions involving beliefs in the paranormal, grandiosity ideas or suspicious thoughts are endorsed at varying degrees among the general population. Here, we investigated the neurobiopsychological basis of the observed inter-individual variability in the propensity toward unfounded beliefs. One hundred two healthy individuals were genotyped for four polymorphisms in the COMT gene (rs6269, rs4633, rs4818, and rs4680, also known as val158met) that define common functional haplotypes with substantial impact on synaptic dopamine degradation, completed a questionnaire measuring unfounded beliefs, and took part in a behavioral experiment assessing perceptual inference. We found that greater dopamine availability was associated with a stronger propensity toward unfounded beliefs, and that this effect was statistically mediated by an enhanced influence of expectations on perceptual inference. Our results indicate that genetic differences in dopaminergic neurotransmission account for inter-individual differences in perceptual inference linked to the formation and maintenance of unfounded beliefs. Thus, dopamine might be critically involved in the processes underlying one's interpretation of the relationship between the self and the world. PMID:26483654

  12. Larger genetic differences within africans than between Africans and Eurasians.

    PubMed Central

    Yu, Ning; Chen, Feng-Chi; Ota, Satoshi; Jorde, Lynn B; Pamilo, Pekka; Patthy, Laszlo; Ramsay, Michele; Jenkins, Trefor; Shyue, Song-Kun; Li, Wen-Hsiung

    2002-01-01

    The worldwide pattern of single nucleotide polymorphism (SNP) variation is of great interest to human geneticists, population geneticists, and evolutionists, but remains incompletely understood. We studied the pattern in noncoding regions, because they are less affected by natural selection than are coding regions. Thus, it can reflect better the history of human evolution and can serve as a baseline for understanding the maintenance of SNPs in human populations. We sequenced 50 noncoding DNA segments each approximately 500 bp long in 10 Africans, 10 Europeans, and 10 Asians. An analysis of the data suggests that the sampling scheme is adequate for our purpose. The average nucleotide diversity (pi) for the 50 segments is only 0.061% +/- 0.010% among Asians and 0.064% +/- 0.011% among Europeans but almost twice as high (0.115% +/- 0.016%) among Africans. The African diversity estimate is even higher than that between Africans and Eurasians (0.096% +/- 0.012%). From available data for noncoding autosomal regions (total length = 47,038 bp) and X-linked regions (47,421 bp), we estimated the pi-values for autosomal regions to be 0.105, 0.070, 0.069, and 0.097% for Africans, Asians, Europeans, and between Africans and Eurasians, and the corresponding values for X-linked regions to be 0.088, 0.042, 0.053, and 0.082%. Thus, Africans differ from one another slightly more than from Eurasians, and the genetic diversity in Eurasians is largely a subset of that in Africans, supporting the out of Africa model of human evolution. Clearly, one must specify the geographic origins of the individuals sampled when studying pi or SNP density. PMID:12019240

  13. Genetic and Environmental Influences on Individual Differences in Printed Word Recognition.

    ERIC Educational Resources Information Center

    Gayan, Javier; Olson, Richard K.

    2003-01-01

    Explored genetic and environmental etiologies of individual differences in printed word recognition and related skills in identical and fraternal twin 8- to 18-year-olds. Found evidence for moderate genetic influences common between IQ, phoneme awareness, and word-reading skills and for stronger IQ-independent genetic influences that were common…

  14. Genetic evaluation of beef carcass data using different endpoint adjustments.

    PubMed

    Rumph, J M; Shafer, W R; Crews, D H; Enns, R M; Lipsey, R J; Quaas, R L; Pollak, E J

    2007-05-01

    Carcass data from 6,795 Simmental-sired animals born from 1992 to 2001 were used to determine whether adjustment to a constant age, back-fat, HCW, or marbling score would result in differences in heritability of the carcass traits and, correspondingly, if EPD calculated using those variance components and adjustments would result in sire reranking. The endpoints were age (EPA), backfat (EPF), HCW (EPC), or marbling (EPM). The traits analyzed were 12th-rib backfat (FAT), HCW, marbling (MRB), LM area (LMA), and percentage retail cuts (PRC). The data were analyzed using an animal model, where contemporary group was included as a fixed effect and was composed of slaughter date, sex, and herd. Random effects included in the model were direct genetic and residual. Estimates of heritability ranged from 0.12 to 0.14, 0.32 to 0.34, and 0.26 to 0.27 for FAT, HCW, and LMA, respectively, for the corresponding endpoints. Heritability for MRB was estimated to be 0.27 at all endpoints. For PRC, estimates of heritability were more variable, with estimates of 0.23 +/- 0.05, 0.32 +/- 0.05, 0.21 +/- 0.05, and 0.20 +/- 0.04 for EPA, EPF, EPC, and EPM, respectively. However, because the EPF and EPC adjustments adjust for a component trait of PRC (FAT and HCW, respectively), they may be altering the trait to one different from PRC. Spearman rank correlations between EPD within a trait using EPA compared with the other endpoints were >0.90 (P < 0.01) for FAT, HCW, MRB, and LMA. For PRC, Spearman rank correlations with EPA EPD were 0.73 (P < 0.01), 0.93 (P < 0.01), and 0.95 (P < 0.01) for EPF, EPC, and EPM, respectively. For most traits and endpoints, there was little reranking among sires when alternative endpoints were used. However, adjusting PRC to EPF appears to result in a greater heritability and substantial re-ranking of sires, potentially due to the adjustment changing the trait to one other than PRC. PMID:17224467

  15. [Genetic analysis of biochemical differences of Yersinia pestis strains].

    PubMed

    Eroshenko, G A; Odinokov, G N; Kukleva, L M; Kutyrev, V V

    2012-01-01

    Literature data and results of our experimental studies on genetic base of biochemical differentiation of Yersinia pestis strains of various subspecies and biovars are summarized in the review. Data on variability of genes coding biochemical features (sugar and alcohol fermentation, nitrate reduction), the differential development of which are the base of existing phenotypic schemes of Y. pestis strains classification, are presented. Variability of these genes was shown to have possible use for the development of genetic classification of Y. pestis strains of various subspecies and biovars. PMID:22830282

  16. Identification of early target genes of aflatoxin B1 in human hepatocytes, inter-individual variability and comparison with other genotoxic compounds

    SciTech Connect

    Josse, Rozenn; Dumont, Julie; Fautrel, Alain; Robin, Marie-Anne; Guillouzo, André

    2012-01-15

    Gene expression profiling has recently emerged as a promising approach to identify early target genes and discriminate genotoxic carcinogens from non-genotoxic carcinogens and non-carcinogens. However, early gene changes induced by genotoxic compounds in human liver remain largely unknown. Primary human hepatocytes and differentiated HepaRG cells were exposed to aflatoxin B1 (AFB1) that induces DNA damage following enzyme-mediated bioactivation. Gene expression profile changes induced by a 24 h exposure of these hepatocyte models to 0.05 and 0.25 μM AFB1 were analyzed by using oligonucleotide pangenomic microarrays. The main altered signaling pathway was the p53 pathway and related functions such as cell cycle, apoptosis and DNA repair. Direct involvement of the p53 protein in response to AFB1 was verified by using siRNA directed against p53. Among the 83 well-annotated genes commonly modulated in two pools of three human hepatocyte populations and HepaRG cells, several genes were identified as altered by AFB1 for the first time. In addition, a subset of 10 AFB1-altered genes, selected upon basis of their function or tumor suppressor role, was tested in four human hepatocyte populations and in response to other chemicals. Although they exhibited large variable inter-donor fold-changes, several of these genes, particularly FHIT, BCAS3 and SMYD3, were found to be altered by various direct and other indirect genotoxic compounds and unaffected by non-genotoxic compounds. Overall, this comprehensive analysis of early gene expression changes induced by AFB1 in human hepatocytes identified a gene subset that included several genes representing potential biomarkers of genotoxic compounds. -- Highlights: ► Gene expression profile changes induced by aflatoxin B1 in human hepatocytes. ► AFB1 modulates various genes including tumor suppressor genes and proto-oncogenes. ► Important inter-individual variations in the response to AFB1. ► Some genes also altered by other

  17. Genetic diversity of Microcystis cyanophages in two different freshwater environments.

    PubMed

    Nakamura, Ginji; Kimura, Shigeko; Sako, Yoshihiko; Yoshida, Takashi

    2014-06-01

    Bacteriophages rapidly diversify their genes through co-evolution with their hosts. We hypothesize that gene diversification of phages leads to locality in phages genome. To test this hypothesis, we investigated the genetic diversity and composition of Microcystis cyanophages using 104 sequences of Ma-LMM01-type cyanophages from two geographically distant sampling sites. The intergenetic region between the ribonucleotide reductase genes nrdA and nrdB was used as the genetic marker. This region contains the host-derived auxiliary metabolic genes nblA, an unknown function gene g04, and RNA ligase gene g03. The sequences obtained were conserved in the Ma-LMM01 gene order and contents. Although the genetic diversity of the sequences was high, it varied by gene. The genetic diversity of nblA was the lowest, suggesting that nblA is a highly significant gene that does not allow mutation. In contrast, g03 sequences had many point mutations. RNA ligase is involved in the counter-host's phage defense mechanism, suggesting that phage defense also plays an important role for rapid gene diversification. The maximum parsimony network and phylogenic analysis showed the sequences from the two sampling sites were distinct. These findings suggest Ma-LMM01-type phages rapidly diversify their genomes through co-evolution with hosts in each location and eventually provided locality of their genomes. PMID:24671440

  18. Association of genetic markers in cattle receiving differing implant protocols

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The potential interaction of growth-promoting implants and genetic markers previously reported to be associated with growth, carcass traits, and tenderness was evaluated. Two implant protocols were applied to subsets of steers (n=383) and heifers (n=65) that were also genotyped for 47 SNP reported ...

  19. Individual Differences in Scotopic Visual Acuity and Contrast Sensitivity: Genetic and Non-Genetic Influences.

    PubMed

    Bartholomew, Alex J; Lad, Eleonora M; Cao, Dingcai; Bach, Michael; Cirulli, Elizabeth T

    2016-01-01

    Despite the large amount of variation found in the night (scotopic) vision capabilities of healthy volunteers, little effort has been made to characterize this variation and factors, genetic and non-genetic, that influence it. In the largest population of healthy observers measured for scotopic visual acuity (VA) and contrast sensitivity (CS) to date, we quantified the effect of a range of variables on visual performance. We found that young volunteers with excellent photopic vision exhibit great variation in their scotopic VA and CS, and this variation is reliable from one testing session to the next. We additionally identified that factors such as Circadian preference, iris color, astigmatism, depression, sex and education have no significant impact on scotopic visual function. We confirmed previous work showing that the amount of time spent on the vision test influences performance and that laser eye surgery results in worse scotopic vision. We also showed a significant effect of intelligence and photopic visual performance on scotopic VA and CS, but all of these variables collectively explain <30% of the variation in scotopic vision. The wide variation seen in young healthy volunteers with excellent photopic vision, the high test-retest agreement, and the vast majority of the variation in scotopic vision remaining unexplained by obvious non-genetic factors suggests a strong genetic component. Our preliminary genome-wide association study (GWAS) of 106 participants ruled out any common genetic variants of very large effect and paves the way for future, larger genetic studies of scotopic vision. PMID:26886100

  20. Individual Differences in Scotopic Visual Acuity and Contrast Sensitivity: Genetic and Non-Genetic Influences

    PubMed Central

    Bartholomew, Alex J.; Lad, Eleonora M.; Cao, Dingcai; Bach, Michael; Cirulli, Elizabeth T.

    2016-01-01

    Despite the large amount of variation found in the night (scotopic) vision capabilities of healthy volunteers, little effort has been made to characterize this variation and factors, genetic and non-genetic, that influence it. In the largest population of healthy observers measured for scotopic visual acuity (VA) and contrast sensitivity (CS) to date, we quantified the effect of a range of variables on visual performance. We found that young volunteers with excellent photopic vision exhibit great variation in their scotopic VA and CS, and this variation is reliable from one testing session to the next. We additionally identified that factors such as Circadian preference, iris color, astigmatism, depression, sex and education have no significant impact on scotopic visual function. We confirmed previous work showing that the amount of time spent on the vision test influences performance and that laser eye surgery results in worse scotopic vision. We also showed a significant effect of intelligence and photopic visual performance on scotopic VA and CS, but all of these variables collectively explain <30% of the variation in scotopic vision. The wide variation seen in young healthy volunteers with excellent photopic vision, the high test-retest agreement, and the vast majority of the variation in scotopic vision remaining unexplained by obvious non-genetic factors suggests a strong genetic component. Our preliminary genome-wide association study (GWAS) of 106 participants ruled out any common genetic variants of very large effect and paves the way for future, larger genetic studies of scotopic vision. PMID:26886100

  1. High Inter-Individual Diversity of Point Mutations, Insertions, and Deletions in Human Influenza Virus Nucleoprotein-Specific Memory B Cells

    PubMed Central

    Bussmann, Bianca M.; Horn, Susanne; Sieg, Michael; Jassoy, Christian

    2015-01-01

    The diversity of virus-specific antibodies and of B cells among different individuals is unknown. Using single-cell cloning of antibody genes, we generated recombinant human monoclonal antibodies from influenza nucleoprotein-specific memory B cells in four adult humans with and without preceding influenza vaccination. We examined the diversity of the antibody repertoires and found that NP-specific B cells used numerous immunoglobulin genes. The heavy chains (HCs) originated from 26 and the kappa light chains (LCs) from 19 different germ line genes. Matching HC and LC chains gave rise to 43 genetically distinct antibodies that bound influenza NP. The median lengths of the CDR3 of the HC, kappa and lambda LC were 14, 9 and 11 amino acids, respectively. We identified changes at 13.6% of the amino acid positions in the V gene of the antibody heavy chain, at 8.4 % in the kappa and at 10.6 % in the lambda V gene. We identified somatic insertions or deletions in 8.1% of the variable genes. We also found several small groups of clonal relatives that were highly diversified. Our findings demonstrate broadly diverse memory B cell repertoires for the influenza nucleoprotein. We found extensive variation within individuals with a high number of point mutations, insertions, and deletions, and extensive clonal diversification. Thus, structurally conserved proteins can elicit broadly diverse and highly mutated B-cell responses. PMID:26086076

  2. Under the Skin: On the Impartial Treatment of Genetic and Environmental Hypotheses of Racial Differences

    ERIC Educational Resources Information Center

    Rowe, David C.

    2005-01-01

    Environmental and genetic explanations have been given for Black-White racial differences in intelligence and other traits. In science, viable, alternative hypotheses are ideally given equal Bayesian prior weights; but this has not been true in the study of racial differences. This article advocates testing environmental and genetic hypotheses of…

  3. Genetic differences between Asian and Caucasian chronic lymphocytic leukemia.

    PubMed

    Kawamata, Norihiko; Moreilhon, Chimene; Saitoh, Takayuki; Karasawa, Masamitsu; Bernstein, Brian K; Sato-Otsubo, Aiko; Ogawa, Seishi; Raynaud, Sophie; Koeffler, H Phillip

    2013-08-01

    Chronic lymphocytic leukemia (CLL) is a common hematological malignancy in Western countries. However, this disease is very rare in Asian countries. It is not clear whether the mechanisms of development of CLL in Caucasians and Asians are the same. We compared genetic abnormalities in Asian and Caucasian CLL using 250k GeneChip arrays. Both Asian and Caucasian CLL had four common genetic abnormalities: deletion of 13q14.3, trisomy 12, abnormalities of ATM (11q) and abnormalities of 17p. Interestingly, trisomy 12 and deletion of 13q14.3 were mutually exclusive in both groups. We also found that deletions of miR 34b/34c (11q), caspase 1/4/5 (11q), Rb1 (13q) and DLC1 (8p) are common in both ethnic groups. Asian CLL more frequently had gain of 3q and 18q. These suggest that classic genomic changes in the Asian and Caucasina CLL are same. Further, we found amplification of IRF4 and deletion of the SP140/SP100 genes; these genes have been reported as CLL-associated genes by previous genome-wide-association study. We have found classic genomic abnormalities in Asian CLL as well as novel genomic alteration in CLL. PMID:23708256

  4. Genetic differentiation and reduced genetic diversity at the northern range edge of two species with different dispersal modes.

    PubMed

    Cahill, Abigail E; Levinton, Jeffrey S

    2016-01-01

    Theory predicts that genetic variation should be reduced at range margins, but empirical support is equivocal. Here, we used genotyping-by-sequencing technology to investigate genetic variation in central and marginal populations of two species in the marine gastropod genus Crepidula. These two species have different development and dispersal types and might therefore show different spatial patterns of genetic variation. Both allelic richness and the proportion of private alleles were highest in the most central populations of both species, and lower at the margin. The species with low dispersal, Crepidula convexa, showed high degrees of structure throughout the range that conform to the pattern found in previous studies using other molecular markers. The northernmost populations of the high-dispersing species, Crepidula fornicata, are distinct from more central populations, although this species has been previously observed to have little genetic structure over much of its range. Although genetic diversity was significantly lower at the range margin, the absolute reduction in diversity observed with these genomewide markers was slight, and it is not yet known whether there are functional consequences for the marginal populations. PMID:26615052

  5. Could the inter-individual variability in cocaine-induced psychotic effects influence the development of cocaine addiction? Towards a new pharmacogenetic approach to addictions.

    PubMed

    Brousse, G; Vorspan, F; Ksouda, K; Bloch, V; Peoc'h, K; Laplanche, J L; Mouly, S; Schmidt, J; Llorca, P M; Lepine, J P

    2010-12-01

    Cocaine addiction is a chronic disease marked by relapses, co-morbidities and the importance of psychosocial consequences. The etiology of cocaine addiction is complex and involves three types of factors: environmental factors, factors linked to the specific effects of cocaine and genetic factors. The latter could explain 40-60% of the risk for developing an addiction. Several studies have looked for a link between cocaine addiction and the genes of the dopaminergic system: the genes DRD2, COMT, SLC6A3 (coding for the dopamine transporter DAT) and DBH (coding for the dopamine beta hydroxylase) but unfortunately very few well established results. Pharmacogenetic approach could be an interesting opportunity for the future. The gene DBH has particularly been linked with the psychotic effects caused by cocaine. This so-called cocaine-induced psychosis (CIP) or cocaine-induced paranoia may influence the development of cocaine addiction. Indeed, these psychotic symptoms during cocaine exposure could cause an aversive effect limiting the development of an addiction. Several functional alterations caused by different mutations of the genes involved in dopaminergic transmission (principally-1021C>T of the gene DBH, but also Val158Met of the gene COMT, TaqI A of the gene DRD2 and VNTR 9 repeat of the DAT) could result in a cocaine-induced psychosis prone phenotype. We are hypothesising that the appearance of CIP during the first contact with cocaine is associated with a lower risk of developing cocaine addiction. This protective effect could be associated with the presence of one or more polymorphisms associated with CIP. A pharmacogenetic approach studying combination of polymorphism could isolate a sub-group of patients at risk for CIPs but more favorably protected from developing an addiction. This theory could enable a better understanding of the protective factors against cocaine addiction and offer new therapeutic or preventive targets in vulnerable sub-groups exposed

  6. Contrasting genetic architectures in different mouse reference populations used for studying complex traits

    PubMed Central

    Buchner, David A.; Nadeau, Joseph H.

    2015-01-01

    Quantitative trait loci (QTLs) are being used to study genetic networks, protein functions, and systems properties that underlie phenotypic variation and disease risk in humans, model organisms, agricultural species, and natural populations. The challenges are many, beginning with the seemingly simple tasks of mapping QTLs and identifying their underlying genetic determinants. Various specialized resources have been developed to study complex traits in many model organisms. In the mouse, remarkably different pictures of genetic architectures are emerging. Chromosome Substitution Strains (CSSs) reveal many QTLs, large phenotypic effects, pervasive epistasis, and readily identified genetic variants. In contrast, other resources as well as genome-wide association studies (GWAS) in humans and other species reveal genetic architectures dominated with a relatively modest number of QTLs that have small individual and combined phenotypic effects. These contrasting architectures are the result of intrinsic differences in the study designs underlying different resources. The CSSs examine context-dependent phenotypic effects independently among individual genotypes, whereas with GWAS and other mouse resources, the average effect of each QTL is assessed among many individuals with heterogeneous genetic backgrounds. We argue that variation of genetic architectures among individuals is as important as population averages. Each of these important resources has particular merits and specific applications for these individual and population perspectives. Collectively, these resources together with high-throughput genotyping, sequencing and genetic engineering technologies, and information repositories highlight the power of the mouse for genetic, functional, and systems studies of complex traits and disease models. PMID:25953951

  7. Different concepts and models of information for family-relevant genetic findings: comparison and ethical analysis.

    PubMed

    Lenk, Christian; Frommeld, Debora

    2015-08-01

    Genetic predispositions often concern not only individual persons, but also other family members. Advances in the development of genetic tests lead to a growing number of genetic diagnoses in medical practice and to an increasing importance of genetic counseling. In the present article, a number of ethical foundations and preconditions for this issue are discussed. Four different models for the handling of genetic information are presented and analyzed including a discussion of practical implications. The different models' ranges of content reach from a strictly autonomous position over self-governed arrangements in the practice of genetic counseling up to the involvement of official bodies and committees. The different models show a number of elements which seem to be very useful for the handling of genetic data in families from an ethical perspective. In contrast, the limitations of the standard medical attempt regarding confidentiality and personal autonomy in the context of genetic information in the family are described. Finally, recommendations for further ethical research and the development of genetic counseling in families are given. PMID:25894235

  8. Statistical analysis of the distribution of amino acids in Borrelia burgdorferi genome under different genetic codes

    NASA Astrophysics Data System (ADS)

    García, José A.; Alvarez, Samantha; Flores, Alejandro; Govezensky, Tzipe; Bobadilla, Juan R.; José, Marco V.

    2004-10-01

    The genetic code is considered to be universal. In order to test if some statistical properties of the coding bacterial genome were due to inherent properties of the genetic code, we compared the autocorrelation function, the scaling properties and the maximum entropy of the distribution of distances of amino acids in sequences obtained by translating protein-coding regions from the genome of Borrelia burgdorferi, under different genetic codes. Overall our results indicate that these properties are very stable to perturbations made by altering the genetic code. We also discuss the evolutionary likely implications of the present results.

  9. Regional differences in awareness and attitudes regarding genetic testing for disease risk and ancestry.

    PubMed

    Jonassaint, Charles R; Santos, Eunice R; Glover, Crystal M; Payne, Perry W; Fasaye, Grace-Ann; Oji-Njideka, Nefertiti; Hooker, Stanley; Hernandez, Wenndy; Foster, Morris W; Kittles, Rick A; Royal, Charmaine D

    2010-09-01

    Little is known about the lay public's awareness and attitudes concerning genetic testing and what factors influence their perspectives. The existing literature focuses mainly on ethnic and socioeconomic differences; however, here we focus on how awareness and attitudes regarding genetic testing differ by geographical regions in the US. We compared awareness and attitudes concerning genetic testing for disease risk and ancestry among 452 adults (41% Black and 67% female) in four major US cities, Norman, OK; Cincinnati, OH; Harlem, NY; and Washington, DC; prior to their participation in genetic ancestry testing. The OK participants reported more detail about their personal ancestries (p = 0.02) and valued ancestry testing over disease testing more than all other sites (p < 0.01). The NY participants were more likely than other sites to seek genetic testing for disease (p = 0.01) and to see benefit in finding out more about one's ancestry (p = 0.02), while the DC participants reported reading and hearing more about genetic testing for African ancestry than all other sites (p < 0.01). These site differences were not better accounted for by sex, age, education, self-reported ethnicity, religion, or previous experience with genetic testing/counseling. Regional differences in awareness and attitudes transcend traditional demographic predictors, such as ethnicity, age and education. Local sociocultural factors, more than ethnicity and socioeconomic status, may influence the public's awareness and belief systems, particularly with respect to genetics. PMID:20549517

  10. Genetic differences based on a beef terminal index are reflected in future phenotypic performance differences in commercial beef cattle.

    PubMed

    Connolly, S M; Cromie, A R; Berry, D P

    2016-05-01

    The increased demand for animal-derived protein and energy for human consumption will have to be achieved through a combination of improved animal genetic merit and better management strategies. The objective of the present study was to quantify whether differences in genetic merit among animals materialised into phenotypic differences in commercial herds. Carcass phenotypes on 156 864 animals from 7301 finishing herds were used, which included carcass weight (kg), carcass conformation score (scale 1 to 15), carcass fat score (scale 1 to 15) at slaughter as well as carcass price. The price per kilogram and the total carcass value that the producer received for the animal at slaughter was also used. A terminal index, calculated in the national genetic evaluations, was obtained for each animal. The index was based on pedigree index for calving performance, feed intake and carcass traits from the national genetic evaluations. Animals were categorised into four terminal index groups on the basis of genetic merit estimates that were derived before the expression of the phenotypic information by the validation animals. The association between terminal index and phenotypic performance at slaughter was undertaken using mixed models; whether the association differed by gender (i.e. young bulls, steers and heifers) or by early life experiences (animals born in a dairy herd or beef herd) was also investigated. The regression coefficient of phenotypic carcass weight, carcass conformation and carcass fat on their respective estimated breeding values (EBVs) was 0.92 kg, 1.08 units and 0.79 units, respectively, which is close to the expectation of one. Relative to animals in the lowest genetic merit group, animals in the highest genetic merit group had, on average, a 38.7 kg heavier carcass, with 2.21 units greater carcass conformation, and 0.82 units less fat. The superior genetic merit animals were, on average, slaughtered 6 days younger than their inferior genetic merit

  11. Genetics

    MedlinePlus

    Homozygous; Inheritance; Heterozygous; Inheritance patterns; Heredity and disease; Heritable; Genetic markers ... The chromosomes are made up of strands of genetic information called DNA. Each chromosome contains sections of ...

  12. Genetics

    MedlinePlus

    ... Inheritance; Heterozygous; Inheritance patterns; Heredity and disease; Heritable; Genetic markers ... The chromosomes are made up of strands of genetic information called DNA. Each chromosome contains sections of ...

  13. Associations of genetic markers in cattle receiving differing implant protocols.

    PubMed

    King, D A; Shackelford, S D; McDaneld, T G; Kuehn, L A; Kemp, C M; Smith, T P L; Wheeler, T L; Koohmaraie, M

    2012-07-01

    The potential interaction of growth-promoting implants and genetic markers previously reported to be associated with growth, carcass traits, and tenderness was evaluated. Two implant protocols were applied to subsets of steers (n = 383) and heifers (n = 65) that were also genotyped for 47 SNP reported to be associated with variation in growth, fat thickness, LM area, marbling, or tenderness. The "mild" protocol consisted of a single terminal implant [16 mg estradiol benzoate (EB), 80 mg trenbalone acetate (TBA) or 8 mg EB, 80 mg TBA given to steers and heifers, respectively]. The "aggressive" protocol consisted of both a growing implant (8 mg EB, 40 mg TBA) for the lightest half of the animals on the aggressive protocol and 2 successive implants (28 mg EB, 200 mg TBA) given to all animals assigned to the aggressive treatment. Implant protocol had measurable impact on BW and ADG (P < 0.05), with the aggressive protocol increasing these traits before the terminal implant (relative to the mild protocol), whereas the mild protocol increased ADG after the terminal implant so that the final BW and ADG over the experimental period were similar between protocols. Animals on the aggressive protocol had significantly increased (P < 0.05) LM area (1.9 cm(2)), slice shear force (1.4 kg), and intact desmin (0.05 units), but decreased (P < 0.05) marbling score (49 units) and adjusted fat thickness (0.1 cm), and yield grade (0.15 units). Among both treatments, 8 of 9 growth-related SNP were associated with BW or ADG, and 6 of 17 tenderness-related SNP were associated with slice shear force or intact desmin. Favorable growth alleles generally were associated with increased carcass yield traits but decreased tenderness. Similarly, favorable tenderness genotypes for some markers were associated with decreased BW and ADG. Some interactions of implant protocol and genotype were noted, with some growth SNP alleles increasing the effect of the aggressive protocol. In contrast, putative

  14. Genetic differences in growth and survival of juvenile hatchery and wild steelhead trout, Salmo gairdneri

    USGS Publications Warehouse

    Reisenbichler, R.R.; McIntyre, J.D.

    1997-01-01

    Relative growth and survival of offspring from matings of hatchery and wild Deschutes River (Oregon) summer steelhead trout, Salmo gairdneri, were measured to determine if hatchery fish differ genetically from wild fish in traits that can affect the stock–recruitment relationship of wild populations. Sections of four natural streams and a hatchery pond were each stocked with genetically marked (lactate dehydrogenase genotypes) eyed eggs or unfed swim-up fry from each of three matings: hatchery × hatchery (HH), hatchery × wild (HW), and wild × wild (WW). In streams, WW fish had the highest survival and HW fish the highest growth rates when significant differences were found; in the hatchery pond, HH fish had the highest survival and growth rates. The hatchery fish were genetically different from wild fish and when they interbreed with wild fish may reduce the number of smolts produced. Hatchery procedures can be modified to reduce the genetic differences between hatchery and wild fish.

  15. Current and Historical Drivers of Landscape Genetic Structure Differ in Core and Peripheral Salamander Populations

    PubMed Central

    Dudaniec, Rachael Y.; Spear, Stephen F.; Richardson, John S.; Storfer, Andrew

    2012-01-01

    With predicted decreases in genetic diversity and greater genetic differentiation at range peripheries relative to their cores, it can be difficult to distinguish between the roles of current disturbance versus historic processes in shaping contemporary genetic patterns. To address this problem, we test for differences in historic demography and landscape genetic structure of coastal giant salamanders (Dicamptodon tenebrosus) in two core regions (Washington State, United States) versus the species' northern peripheral region (British Columbia, Canada) where the species is listed as threatened. Coalescent-based demographic simulations were consistent with a pattern of post-glacial range expansion, with both ancestral and current estimates of effective population size being much larger within the core region relative to the periphery. However, contrary to predictions of recent human-induced population decline in the less genetically diverse peripheral region, there was no genetic signature of population size change. Effects of current demographic processes on genetic structure were evident using a resistance-based landscape genetics approach. Among core populations, genetic structure was best explained by length of the growing season and isolation by resistance (i.e. a ‘flat’ landscape), but at the periphery, topography (slope and elevation) had the greatest influence on genetic structure. Although reduced genetic variation at the range periphery of D. tenebrosus appears to be largely the result of biogeographical history rather than recent impacts, our analyses suggest that inherent landscape features act to alter dispersal pathways uniquely in different parts of the species' geographic range, with implications for habitat management. PMID:22590604

  16. Sex differences in the genetic and environmental influences on childhood conduct disorder and adult antisocial behavior.

    PubMed

    Meier, Madeline H; Slutske, Wendy S; Heath, Andrew C; Martin, Nicholas G

    2011-05-01

    Sex differences in the genetic and environmental influences on childhood conduct disorder and adult antisocial behavior were examined in a large community sample of 6,383 adult male, female, and opposite-sex twins. Retrospective reports of childhood conduct disorder (prior to 18 years of age) were obtained when participants were approximately 30 years old, and lifetime reports of adult antisocial behavior (antisocial behavior after 17 years of age) were obtained 8 years later. Results revealed that either the genetic or the shared environmental factors influencing childhood conduct disorder differed for males and females (i.e., a qualitative sex difference), but by adulthood, these sex-specific influences on antisocial behavior were no longer apparent. Further, genetic and environmental influences accounted for proportionally the same amount of variance in antisocial behavior for males and females in childhood and adulthood (i.e., there were no quantitative sex differences). Additionally, the stability of antisocial behavior from childhood to adulthood was slightly greater for males than females. Though familial factors accounted for more of the stability of antisocial behavior for males than females, genetic factors accounted for the majority of the covariation between childhood conduct disorder and adult antisocial behavior for both sexes. The genetic influences on adult antisocial behavior overlapped completely with the genetic influences on childhood conduct disorder for both males and females. Implications for future twin and molecular genetic studies are discussed. PMID:21319923

  17. Different but Equal? How Nonmajors and Majors Approach and Learn Genetics

    ERIC Educational Resources Information Center

    Knight, Jennifer K.; Smith, Michelle K.

    2010-01-01

    Introductory biology courses are frequently offered separately to biology majors and nonbiology majors, with the assumption that the two groups of students are different enough to merit different courses. To assess the evidence behind this assumption, we compared students in two different genetics classes at the University of Colorado-Boulder, one…

  18. Genetic, molecular and physiological basis of variation in Drosophila gut immunocompetence

    PubMed Central

    Bou Sleiman, Maroun S.; Osman, Dani; Massouras, Andreas; Hoffmann, Ary A.; Lemaitre, Bruno; Deplancke, Bart

    2015-01-01

    Gut immunocompetence involves immune, stress and regenerative processes. To investigate the determinants underlying inter-individual variation in gut immunocompetence, we perform enteric infection of 140 Drosophila lines with the entomopathogenic bacterium Pseudomonas entomophila and observe extensive variation in survival. Using genome-wide association analysis, we identify several novel immune modulators. Transcriptional profiling further shows that the intestinal molecular state differs between resistant and susceptible lines, already before infection, with one transcriptional module involving genes linked to reactive oxygen species (ROS) metabolism contributing to this difference. This genetic and molecular variation is physiologically manifested in lower ROS activity, lower susceptibility to ROS-inducing agent, faster pathogen clearance and higher stem cell activity in resistant versus susceptible lines. This study provides novel insights into the determinants underlying population-level variability in gut immunocompetence, revealing how relatively minor, but systematic genetic and transcriptional variation can mediate overt physiological differences that determine enteric infection susceptibility. PMID:26213329

  19. Habitat differences influence genetic impacts of human land use on the American beech (Fagus grandifolia).

    PubMed

    Lumibao, Candice Y; McLachlan, Jason S

    2014-01-01

    Natural reforestation after regional forest clearance is a globally common land-use sequence. The genetic recovery of tree populations in these recolonized forests may depend on the biogeographic setting of the landscape, for instance whether they are in the core or in the marginal part of the species' range. Using data from 501 individuals genotyped across 7 microsatellites, we investigated whether regional differences in habitat quality affected the recovery of genetic variation in a wind-pollinated tree species, American beech (Fagus grandifolia) in Massachusetts. We compared populations in forests that were recolonized following agricultural abandonment to those in remnant forests that have only been logged in both central inland and marginal coastal regions. Across all populations in our entire study region, recolonized forests showed limited reduction of genetic diversity as only observed heterozygosity was significantly reduced in these forests (H(O) = 0.520 and 0.590, respectively). Within inland region, this pattern was observed, whereas in the coast, recolonized populations exhibited no reduction in all genetic diversity estimates. However, genetic differentiation among recolonized populations in marginal coastal habitat increased (F(st) logged = 0.072; F(st) secondary = 0.249), with populations showing strong genetic structure, in contrast to inland region. These results indicate that the magnitude of recovery of genetic variation in recolonized populations can vary at different habitats. PMID:25138571

  20. Predicting risk in space: Genetic markers for differential vulnerability to sleep restriction

    NASA Astrophysics Data System (ADS)

    Goel, Namni; Dinges, David F.

    2012-08-01

    Several laboratories have found large, highly reliable individual differences in the magnitude of cognitive performance, fatigue and sleepiness, and sleep homeostatic vulnerability to acute total sleep deprivation and to chronic sleep restriction in healthy adults. Such individual differences in neurobehavioral performance are also observed in space flight as a result of sleep loss. The reasons for these stable phenotypic differential vulnerabilities are unknown: such differences are not yet accounted for by demographic factors, IQ or sleep need, and moreover, psychometric scales do not predict those individuals cognitively vulnerable to sleep loss. The stable, trait-like (phenotypic) inter-individual differences observed in response to sleep loss—with intraclass correlation coefficients accounting for 58-92% of the variance in neurobehavioral measures—point to an underlying genetic component. To this end, we utilized multi-day highly controlled laboratory studies to investigate the role of various common candidate gene variants—each independently—in relation to cumulative neurobehavioral and sleep homeostatic responses to sleep restriction. These data suggest that common genetic variations (polymorphisms) involved in sleep-wake, circadian, and cognitive regulation may serve as markers for prediction of inter-individual differences in sleep homeostatic and neurobehavioral vulnerability to sleep restriction in healthy adults. Identification of genetic predictors of differential vulnerability to sleep restriction—as determined from candidate gene studies—will help identify astronauts most in need of fatigue countermeasures in space flight and inform medical standards for obtaining adequate sleep in space. This review summarizes individual differences in neurobehavioral vulnerability to sleep deprivation and ongoing genetic efforts to identify markers of such differences.

  1. Regional differences in awareness and attitudes regarding genetic testing for disease risk and ancestry

    PubMed Central

    Jonassaint, Charles R.; Santos, Eunice R.; Glover, Crystal M.; Payne, Perry W.; Fasaye, Grace-Ann; Oji-Njideka, Nefertiti; Hooker, Stanley; Hernandez, Wenndy; Foster, Morris W.; Kittles, Rick A.

    2010-01-01

    Little is known about the lay public’s awareness and attitudes concerning genetic testing and what factors influence their perspectives. The existing literature focuses mainly on ethnic and socioeconomic differences; however, here we focus on how awareness and attitudes regarding genetic testing differ by geographical regions in the US. We compared awareness and attitudes concerning genetic testing for disease risk and ancestry among 452 adults (41% Black and 67% female) in four major US cities, Norman, OK; Cincinnati, OH; Harlem, NY; and Washington, DC; prior to their participation in genetic ancestry testing. The OK participants reported more detail about their personal ancestries (p = 0.02) and valued ancestry testing over disease testing more than all other sites (p < 0.01). The NY participants were more likely than other sites to seek genetic testing for disease (p = 0.01) and to see benefit in finding out more about one’s ancestry (p = 0.02), while the DC participants reported reading and hearing more about genetic testing for African ancestry than all other sites (p < 0.01). These site differences were not better accounted for by sex, age, education, self-reported ethnicity, religion, or previous experience with genetic testing/counseling. Regional differences in awareness and attitudes transcend traditional demographic predictors, such as ethnicity, age and education. Local sociocultural factors, more than ethnicity and socioeconomic status, may influence the public’s awareness and belief systems, particularly with respect to genetics. PMID:20549517

  2. Thermographic evaluation of climatic conditions on lambs from different genetic groups

    NASA Astrophysics Data System (ADS)

    do Prado Paim, Tiago; Borges, Bárbara Oliveira; de Mello Tavares Lima, Paulo; Gomes, Edgard Franco; Dallago, Bruno Stéfano Lima; Fadel, Rossala; de Menezes, Adriana Morato; Louvandini, Helder; Canozzi, Maria Eugênia Andrighetto; Barcellos, Júlio Otavio Jardim; McManus, Concepta

    2013-01-01

    In production systems the characterization of genetic resources in relation to their capacity to respond to environmental conditions is necessary. The objective of this study was to evaluate the use of infrared thermography for separation of animals from different genetic groups and determine which phenotypic traits are important for climatic adaptation. A total of 126 suckling lambs from four different genetic groups (Santa Inês - SI, Bergamasca - B, Bergamasca X Santa Inês - BS, and Ile de France X Santa Inês - IL) were used. The animals were divided into two groups, one housed and another in an outside paddock. Thermograph photographs were taken at four-hour intervals over three full days. Temperatures of the nose, skull, neck, fore and rear flanks and rump were measured, as well as coat depth, the density and length of hairs, reflectance and color. The daily temperature range during the experimental period was more than 20°C, with animals experiencing heat (12 h to 15 h) and cold (24 h to 4 h) stress. The three main phenotypic traits that influenced genetic group separation were hair density, height of coat, and length of hairs. Thermograph temperatures were able to detect different responses of the genetic groups to the environment. Therefore, infrared thermography is a promising technique to evaluate the response of animals to the environment and to differentiate between genetic groups.

  3. Genetics of obesity

    PubMed Central

    O'Rahilly, Stephen; Farooqi, I.Sadaf

    2006-01-01

    Considerable attention is currently being paid to the secular changes in food intake and physical activity that underlie the increase in the prevalence of obesity that is apparent in many societies. While this is laudable it would be unwise to view these environmental factors in isolation from the biological factors that normally control body weight and composition and the compelling evidence that inter-individual differences in susceptibility to obesity have strong genetic determinants. This is particularly important, as it is only in the past decade that we have begun to obtain substantive information regarding the molecular constituents of pathways controlling mammalian energy balance and therefore, for the first time, are in a position to achieve a better mechanistic understanding of this disease. Population-based association and linkage studies have highlighted a number of loci at which genetic variation is associated with obesity and related phenotypes and the identification and characterization of monogenic obesity syndromes has been particularly fruitful. While there is widespread acceptance that hereditary factors might predispose to human obesity, it is frequently assumed that such factors would influence metabolic rate or the selective partitioning of excess calories into fat. However, it is notable that, thus far, all monogenic defects causing human obesity actually disrupt hypothalamic pathways and have a profound effect on satiety and food intake. To conclude, the evidence we have to date suggests that the major impact of genes on human obesity is just as likely (or perhaps more likely) to directly impact on hunger, satiety and food intake rather than metabolic rate or nutrient partitioning. At the risk of oversimplification, it seems that from an aetiological/genetic standpoint, human obesity appears less a metabolic than a neuro-behavioural disease. PMID:16815794

  4. Genetic analysis of fruit shape traits at different maturation stages in sponge gourd*

    PubMed Central

    Zhang, Sheng; Hu, Jin; Zhang, Cai-fang; Guan, Ya-jing; Zhang, Ying

    2007-01-01

    The fruit shape is important quantitative trait closely related to the fruit quality. However, the genetic model of fruit shapes has not been proposed. Therefore, in the present study, analysis of genetic effects for fruit shape traits (fruit length and fruit perimeter) in sponge gourd was conducted by employing a developmental genetic model including fruit direct effects and maternal effects. Analysis approaches of unconditional and conditional variances were applied to evaluate the genetic behavior of fruit shape traits at economical and physiological maturation times. The results of variance analysis indicated that fruit length and fruit perimeter were simultaneously affected by fruit direct genetic effects and maternal effects. Fruit direct genetic effects were relatively more important for fruit shape traits at whole developmental period. The gene expression was most active at the economical maturation stage (1~12 d after flowering) for two shape traits, and the activation of gene was mostly due to direct dominance effects at physiological maturation stage (13~60 d after flowering). The coefficients due to different genetic effects, as well as the phenotypic correlation coefficients, varied significantly between fruit shape traits themselves at various maturation stages. The results showed that it was relatively easy to improve fruit shape traits for industrial purpose by carefully selecting the parents at economical maturation stage instead of that at physiological maturation stage. PMID:17542062

  5. The Similarities and Differences between Intracranial and Spinal Ependymomas : A Review from a Genetic Research Perspective.

    PubMed

    Lee, Chang-Hyun; Chung, Chun Kee; Ohn, Jung Hun; Kim, Chi Heon

    2016-03-01

    Ependymomas occur in both the brain and spine. The prognosis of these tumors sometimes differs for different locations. The genetic landscape of ependymoma is very heterogeneous despite the similarity of histopathologic findings. In this review, we describe the genetic differences between spinal ependymomas and their intracranial counterparts to better understand their prognosis. From the literature review, many studies have reported that spinal cord ependymoma might be associated with NF2 mutation, NEFL overexpression, Merlin loss, and 9q gain. In myxopapillary ependymoma, NEFL and HOXB13 overexpression were reported to be associated. Prior studies have identified HIC-1 methylation, 4.1B deletion, and 4.1R loss as common features in intracranial ependymoma. Supratentorial ependymoma is usually characterized by NOTCH-1 mutation and p75 expression. TNC mutation, no hypermethylation of RASSF1A, and GFAP/NeuN expression may be diagnostic clues of posterior fossa ependymoma. Although MEN1, TP53, and PTEN mutations are rarely reported in ependymoma, they may be related to a poor prognosis, such as recurrence or metastasis. Spinal ependymoma has been found to be quite different from intracranial ependymoma in genetic studies, and the favorable prognosis in spinal ependymoma may be the result of the genetic differences. A more detailed understanding of these various genetic aberrations may enable the identification of more specific prognostic markers as well as the development of customized targeted therapies. PMID:26962412

  6. The Similarities and Differences between Intracranial and Spinal Ependymomas : A Review from a Genetic Research Perspective

    PubMed Central

    Lee, Chang-Hyun; Ohn, Jung Hun; Kim, Chi Heon

    2016-01-01

    Ependymomas occur in both the brain and spine. The prognosis of these tumors sometimes differs for different locations. The genetic landscape of ependymoma is very heterogeneous despite the similarity of histopathologic findings. In this review, we describe the genetic differences between spinal ependymomas and their intracranial counterparts to better understand their prognosis. From the literature review, many studies have reported that spinal cord ependymoma might be associated with NF2 mutation, NEFL overexpression, Merlin loss, and 9q gain. In myxopapillary ependymoma, NEFL and HOXB13 overexpression were reported to be associated. Prior studies have identified HIC-1 methylation, 4.1B deletion, and 4.1R loss as common features in intracranial ependymoma. Supratentorial ependymoma is usually characterized by NOTCH-1 mutation and p75 expression. TNC mutation, no hypermethylation of RASSF1A, and GFAP/NeuN expression may be diagnostic clues of posterior fossa ependymoma. Although MEN1, TP53, and PTEN mutations are rarely reported in ependymoma, they may be related to a poor prognosis, such as recurrence or metastasis. Spinal ependymoma has been found to be quite different from intracranial ependymoma in genetic studies, and the favorable prognosis in spinal ependymoma may be the result of the genetic differences. A more detailed understanding of these various genetic aberrations may enable the identification of more specific prognostic markers as well as the development of customized targeted therapies. PMID:26962412

  7. Genetic and epigenetic alterations induced by different levels of rye genome integration in wheat recipient.

    PubMed

    Zheng, X L; Zhou, J P; Zang, L L; Tang, A T; Liu, D Q; Deng, K J; Zhang, Y

    2016-01-01

    The narrow genetic variation present in common wheat (Triticum aestivum) varieties has greatly restricted the improvement of crop yield in modern breeding systems. Alien addition lines have proven to be an effective means to broaden the genetic diversity of common wheat. Wheat-rye addition lines, which are the direct bridge materials for wheat improvement, have been wildly used to produce new wheat cultivars carrying alien rye germplasm. In this study, we investigated the genetic and epigenetic alterations in two sets of wheat-rye disomic addition lines (1R-7R) and the corresponding triticales. We used expressed sequence tag-simple sequence repeat, amplified fragment length polymorphism, and methylation-sensitive amplification polymorphism analyses to analyze the effects of the introduction of alien chromosomes (either the entire genome or sub-genome) to wheat genetic background. We found obvious and diversiform variations in the genomic primary structure, as well as alterations in the extent and pattern of the genomic DNA methylation of the recipient. Meanwhile, these results also showed that introduction of different rye chromosomes could induce different genetic and epigenetic alterations in its recipient, and the genetic background of the parents is an important factor for genomic and epigenetic variation induced by alien chromosome addition. PMID:27323191

  8. Genetic Analysis of Phytophthora nicotianae Populations from Different Hosts Using Microsatellite Markers.

    PubMed

    Biasi, Antonio; Martin, Frank N; Cacciola, Santa O; di San Lio, Gaetano Magnano; Grünwald, Niklaus J; Schena, Leonardo

    2016-09-01

    In all, 231 isolates of Phytophthora nicotianae representing 14 populations from different host genera, including agricultural crops (Citrus, Nicotiana, and Lycopersicon), potted ornamental species in nurseries (Lavandula, Convolvulus, Myrtus, Correa, and Ruta), and other plant genera were characterized using simple-sequence repeat markers. In total, 99 multilocus genotypes (MLG) were identified, revealing a strong association between genetic grouping and host of recovery, with most MLG being associated with a single host genus. Significant differences in the structure of populations were revealed but clonality prevailed in all populations. Isolates from Citrus were found to be genetically related regardless of their geographic origin and were characterized by high genetic uniformity and high inbreeding coefficients. Higher variability was observed for other populations and a significant geographical structuring was determined for isolates from Nicotiana. Detected differences were related to the propagation and cultivation systems of different crops. Isolates obtained from Citrus spp. are more likely to be distributed worldwide with infected plant material whereas Nicotiana and Lycopersicon spp. are propagated by seed, which would not contribute to the spread of the pathogen and result in a greater chance for geographic isolation of lineages. With regard to ornamental species in nurseries, the high genetic variation is likely the result of the admixture of diverse pathogen genotypes through the trade of infected plant material from various geographic origins, the presence of several hosts in the same nursery, and genetic recombination through sexual reproduction of this heterothallic species. PMID:27111805

  9. Differences in Common Genetic Predisposition to Ischemic Stroke by Age and Sex

    PubMed Central

    Rutten-Jacobs, Loes C.A.; Holliday, Elizabeth G.; Malik, Rainer; Sudlow, Cathie; Rothwell, Peter M.; Maguire, Jane M.; Koblar, Simon A.; Bevan, Steve; Boncoraglio, Giorgio; Dichgans, Martin; Levi, Chris; Lewis, Cathryn M.; Markus, Hugh S.

    2015-01-01

    Background and Purpose— Evidence from epidemiological studies points to differences in factors predisposing to stroke by age and sex. Whether these arise because of different genetic influences remained untested. Here, we use data from 4 genome-wide association data sets to study the relationship between genetic influence on stroke with both age and sex. Methods— Using genomic-relatedness-matrix restricted maximum likelihood methods, we performed 4 analyses: (1) we calculated the genetic correlation between groups divided by age and (2) by sex, (3) we calculated the heritability of age-at-stroke-onset, and (4) we evaluated the evidence that heritability of stroke is greater in women than in men. Results— We found that genetic factors influence age at stroke onset (h2 [SE]=18.0 [6.8]; P=0.0038), with a trend toward a stronger influence in women (women: h2 [SE]=21.6 [3.5]; Men: h2 [SE]=13.9 [2.8]). Although a moderate proportion of genetic factors was shared between sexes (rG [SE]=0.68 [0.16]) and between younger and older cases (rG [SE]=0.70 [0.17]), there was evidence to suggest that there are genetic susceptibility factors that are specific to sex (P=0.037) and to younger or older groups (P=0.056), particularly for women (P=0.0068). Finally, we found a trend toward higher heritability of stroke in women although this was not significantly greater than in men (P=0.084). Conclusions— Our results indicate that there are genetic factors that are either unique to or have a different effect between younger and older age groups and between women and men. Performing large, well-powered genome-wide association study analyses in these groups is likely to uncover further associations. PMID:26443828

  10. Genetic alterations and cancer formation in a European flatfish at sites of different contaminant burdens.

    PubMed

    Lerebours, Adélaïde; Stentiford, Grant D; Lyons, Brett P; Bignell, John P; Derocles, Stéphane A P; Rotchell, Jeanette M

    2014-09-01

    Fish diseases are an indicator for marine ecosystem health since they provide a biological end-point of historical exposure to stressors. Liver cancer has been used to monitor the effects of exposure to anthropogenic pollution in flatfish for many years. The prevalence of liver cancer can exceed 20%. Despite the high prevalence and the opportunity of using flatfish to study environmentally induced cancer, the genetic and environmental factors driving tumor prevalence across sites are poorly understood. This study aims to define the link between genetic deterioration, liver disease progression, and anthropogenic contaminant exposures in the flatfish dab (Limanda limanda). We assessed genetic changes in a conserved cancer gene, Retinoblastoma (Rb), in association with histological diagnosis of normal, pretumor, and tumor pathologies in the livers of 165 fish from six sites in the North Sea and English Channel. The highest concentrations of metals (especially cadmium) and organic chemicals correlated with the presence of tumor pathology and with defined genetic profiles of the Rb gene, from these sites. Different Rb genetic profiles were found in liver tissue near each tumor phenotype, giving insight into the mechanistic molecular-level cause of the liver pathologies. Different Rb profiles were also found at sampling sites of differing contaminant burdens. Additionally, profiles indicated that histological "normal" fish from Dogger sampling locations possessed Rb profiles associated with pretumor disease. This study highlights an association between Rb and specific contaminants (especially cadmium) in the molecular etiology of dab liver tumorigenesis. PMID:25102285

  11. Facial emotion perception differs in young persons at genetic and clinical high-risk for psychosis.

    PubMed

    Kohler, Christian G; Richard, Jan A; Brensinger, Colleen M; Borgmann-Winter, Karin E; Conroy, Catherine G; Moberg, Paul J; Gur, Ruben C; Gur, Raquel E; Calkins, Monica E

    2014-05-15

    A large body of literature has documented facial emotion perception impairments in schizophrenia. More recently, emotion perception has been investigated in persons at genetic and clinical high-risk for psychosis. This study compared emotion perception abilities in groups of young persons with schizophrenia, clinical high-risk, genetic risk and healthy controls. Groups, ages 13-25, included 24 persons at clinical high-risk, 52 first-degree relatives at genetic risk, 91 persons with schizophrenia and 90 low risk persons who completed computerized testing of emotion recognition and differentiation. Groups differed by overall emotion recognition abilities and recognition of happy, sad, anger and fear expressions. Pairwise comparisons revealed comparable impairments in recognition of happy, angry, and fearful expressions for persons at clinical high-risk and schizophrenia, while genetic risk participants were less impaired, showing reduced recognition of fearful expressions. Groups also differed for differentiation of happy and sad expressions, but differences were mainly between schizophrenia and control groups. Emotion perception impairments are observable in young persons at-risk for psychosis. Preliminary results with clinical high-risk participants, when considered along findings in genetic risk relatives, suggest social cognition abilities to reflect pathophysiological processes involved in risk of schizophrenia. PMID:24582775

  12. A Genetic Approach to Spanish Populations of the Threatened Austropotamobius italicus Located at Three Different Scenarios

    PubMed Central

    Matallanas, Beatriz; Callejas, Carmen; Ochando, M. Dolores

    2012-01-01

    Spanish freshwater ecosystems are suffering great modification and some macroinvertebrates like Austropotamobius italicus, the white-clawed crayfish, are threatened. This species was once widely distributed in Spain, but its populations have shown a very strong decline over the last thirty years, due to different factors. Three Spanish populations of this crayfish—from different scenarios—were analysed with nuclear (microsatellites) and mitochondrial markers (COI and 16S rDNA). Data analyses reveal the existence of four haplotypes at mitochondrial level and polymorphism for four microsatellite loci. Despite this genetic variability, bottlenecks were detected in the two natural Spanish populations tested. In addition, the distribution of the mitochondrial haplotypes and SSR alleles show a similar geographic pattern and the genetic differentiation between these samples is mainly due to genetic drift. Given the current risk status of the species across its range, this diversity offers some hope for the species from a management point of view. PMID:22645491

  13. Genetic Differences Between Great Apes and Humans: Implications for Human Evolution

    SciTech Connect

    Varki, Ajit

    2004-03-17

    When considering protein sequences, humans are 99-100% identical to chimpanzees and bonobos, our closest evolutionary relatives. The evolution of humans (and the unique features of our species) from a common ancestor with these great apes involved many steps, influenced by interactions amongst factors of genetic, developmental, ecological, microbial, climatic, behavioral, cultural and social origin. The genetic factors can be approached by direct comparisons of human and great ape genomes, genes and gene products, and by elucidating biochemical and biological consequences of the differences. We have discovered multiple genetic and biochemical differences between humans and great apes, particularly in relationship to a family of cell surface molecules called sialic acids. These differences have implications for the human condition, ranging from susceptibility or resistance to microbial pathogens; effects on endogenous receptors in the immune system; potential effects on placental signaling; the expression of oncofetal antigens in cancers; consequences of dietary intake of animal foods; and the development of the mammalian brain. This talk will provide an overview of these and other genetic differences between humans and great apes, with attention to differences potentially relevant to the evolution of humans.

  14. Genetic structure of Leptopilina boulardi populations from different climatic zones of Iran

    PubMed Central

    2011-01-01

    Background The genetic structure of populations can be influenced by geographic isolation (including physical distance) and ecology. We examined these effects in Leptopilina boulardi, a parasitoid of Drosophila of African origin and widely distributed over temperate and (sub) tropical climates. Results We sampled 11 populations of L. boulardi from five climatic zones in Iran and measured genetic differentiation at nuclear (Amplified Fragment Length Polymorphism; AFLP) and mitochondrial (Cytochrome Oxidase I; COI) loci. An Analysis of Molecular Variance (AMOVA) for the AFLP data revealed that 67.45% of variation resided between populations. No significant variation was observed between climatic zones. However, a significant difference was detected between populations from the central (dry) regions and those from the wetter north, which are separated by desert. A similarly clear cut genetic differentiation between populations from the central part of Iran and those from the north was observed by UPGMA cluster analysis and Principal Coordinates Analysis (PCO). Both UPGMA and PCO further separated two populations from the very humid western Caspian Sea coast (zone 3) from other northern populations from the temperate Caspian Sea coastal plain (zone 2), which are connected by forest. One population (Nour) was genetically intermediate between these two zones, indicating some gene flow between these two groups of populations. In all analyses a mountain population, Sorkhabad was found to be genetically identical to those from the nearby coastal plain (zone 2), which indicates high gene flow between these populations over a short geographical distance. One population from the Caspian coast (Astaneh) was genetically highly diverged from all other populations. A partial Mantel test showed a highly significant positive correlation between genetic and geographic distances, as well as separation by the deserts of central Iran. The COI sequences were highly conserved among all

  15. The genetic basis of pigmentation differences within and between Drosophila species

    PubMed Central

    Massey, Jonathan; Wittkopp, Patricia J.

    2016-01-01

    In Drosophila, as well as in many other plants and animals, pigmentation is highly variable both within and between species. This variability, combined with powerful genetic and transgenic tools as well as knowledge of how pigment patterns are formed biochemically and developmentally, have made Drosophila pigmentation a premier system for investigating the genetic and molecular mechanisms responsible for phenotypic evolution. In this chapter, we review and synthesize findings from a rapidly growing body of case studies examining the genetic basis of pigmentation differences in the abdomen, thorax, wings, and pupal cases within and between Drosophila species. A core set of genes, including genes required for pigment synthesis (e.g., yellow, ebony, tan, Dat) as well as developmental regulators of these genes (e.g., bab1, bab2, omb, Dll, and wg) emerge as the primary sources of this variation, with most genes having been shown to contribute to pigmentation differences both within and between species. In cases where specific genetic changes contributing to pigmentation divergence were identified in these genes, the changes were always located in noncoding sequences and affected cis-regulatory activity. We conclude this chapter by discussing these and other lessons learned from evolutionary genetic studies of Drosophila pigmentation and identify topics we think should be the focus of future work with this model system. PMID:27282023

  16. The Genetic Basis of Pigmentation Differences Within and Between Drosophila Species.

    PubMed

    Massey, J H; Wittkopp, P J

    2016-01-01

    In Drosophila, as well as in many other plants and animals, pigmentation is highly variable both within and between species. This variability, combined with powerful genetic and transgenic tools as well as knowledge of how pigment patterns are formed biochemically and developmentally, has made Drosophila pigmentation a premier system for investigating the genetic and molecular mechanisms responsible for phenotypic evolution. In this chapter, we review and synthesize findings from a rapidly growing body of case studies examining the genetic basis of pigmentation differences in the abdomen, thorax, wings, and pupal cases within and between Drosophila species. A core set of genes, including genes required for pigment synthesis (eg, yellow, ebony, tan, Dat) as well as developmental regulators of these genes (eg, bab1, bab2, omb, Dll, and wg), emerge as the primary sources of this variation, with most genes having been shown to contribute to pigmentation differences both within and between species. In cases where specific genetic changes contributing to pigmentation divergence were identified in these genes, the changes were always located in noncoding sequences and affected cis-regulatory activity. We conclude this chapter by discussing these and other lessons learned from evolutionary genetic studies of Drosophila pigmentation and identify topics we think should be the focus of future work with this model system. PMID:27282023

  17. Individual Differences in Executive Functions Are Almost Entirely Genetic in Origin

    PubMed Central

    Friedman, Naomi P.; Miyake, Akira; Young, Susan E.; DeFries, John C.; Corley, Robin P.; Hewitt, John K.

    2009-01-01

    Recent psychological and neuropsychological research suggests that executive functions — the cognitive control processes that regulate thought and action — are multifaceted and that different types of executive functions are correlated but separable. The present multivariate twin study of three executive functions (inhibiting dominant responses, updating working memory representations, and shifting between task sets), measured as latent variables, examined why people vary in these executive control abilities and why these abilities are correlated but separable from a behavioral genetic perspective. Results indicated that executive functions are correlated because they are influenced by a highly heritable (99%) common factor that goes beyond general intelligence or perceptual speed, and they are separable because of additional genetic influences unique to particular executive functions. This combination of general and specific genetic influences places executive functions among the most heritable psychological traits. These results highlight the potential of genetic approaches for uncovering the biological underpinnings of executive functions and suggest a need for examining multiple types of executive functions to distinguish different levels of genetic influences. PMID:18473654

  18. Genetic parameters for EUROP carcass traits within different groups of cattle in Ireland.

    PubMed

    Hickey, J M; Keane, M G; Kenny, D A; Cromie, A R; Veerkamp, R F

    2007-02-01

    The first objective of this study was to test the ability of systems of weighing and classifying bovine carcasses used in commercial abattoirs in Ireland to provide information that can be used for the purposes of genetic evaluation of carcass weight, carcass fatness class, and carcass conformation class. Secondly, the study aimed to test whether genetic and phenotypic variances differed by breed of sire. Variance components for carcass traits were estimated for crosses between dairy cows and 8 breeds of sire commonly found in the Irish cattle population. These 8 breeds were Aberdeen Angus, Belgian Blue, Charolais, Friesian, Hereford, Holstein, Limousin, and Simmental. A multivariate animal model was used to estimate genetic parameters within the Holstein sire breed group. Univariate analyses were used to estimate variance components for the remaining 7 sire breed groups. Multivariate sire models were used to formally test differences in genetic variances in sire breed groups. Field data on 64,443 animals, which were slaughtered in commercial abattoirs between the ages of 300 and 875 d, were analyzed in 8 analyses. Carcass fat class and carcass conformation class were measured using the European Union beef carcass classification system (EUROP) scale. For all 3 traits, the sire breed group with the greatest genetic variance had a value of more than 8 times the sire breed group with least genetic variance. Heritabilities ranged from zero to moderate for carcass fatness class (0.00 to 0.40), from low to moderate for carcass conformation class (0.04 to 0.36), and from low to high for carcass weight (0.06 to 0.65). Carcass weight was the most heritable (0.26) of the 3 traits. Carcass conformation class and carcass fatness class were equally heritable (0.17). Genetic and phenotypic correlations were all positive in the Holstein sire breed group. The genetic correlations varied from 0.11 for the relationship between carcass weight and carcass fatness class to 0.44 for the

  19. Gender Difference Does Not Mean Genetic Difference: Externalizing Improves Performance in Mental Rotation

    ERIC Educational Resources Information Center

    Moe, Angelica

    2012-01-01

    The fear of underperforming owing to stereotype threat affects women's performance in tasks such as mathematics, chess, and spatial reasoning. The present research considered mental rotation and explored effects on performance and on regulatory focus of instructions pointing to different explanations for gender differences. Two hundred and one…

  20. Behavior Problems among Children from Different Family Structures: The Influence of Genetic Self-Selection.

    ERIC Educational Resources Information Center

    Cleveland, H. Harrington; Wiebe, Richard P.; van den Oord, Edwin J. C. G.; Rowe, David C.

    2000-01-01

    Examined influences on children's behavior problems in households defined by marital status and sibling relatedness. Found that genetic influences accounted for 81 to 94 percent of mean-level difference in behavior problems between two-parent/full sibling, and the mother-only/half sibling groups. Shared environmental influences accounted for 67 to…

  1. Sex Differences in Speed of Mental Rotation and the X-Linked Genetic Hypothesis.

    ERIC Educational Resources Information Center

    Thomas, Hoben; Kail, Robert

    1991-01-01

    Mental-rotation task response times from 12 studies involving 505 adults--251 males and 254 females--were used to evaluate 5 hypotheses concerning sex differences derived from an X-linked genetic model. The model assumes that task facilitation in speed of mental rotation is mediated by a recessive gene. Four hypotheses derived from the model were…

  2. Genetics of end-use quality differences between a modern and historical spring wheat

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The goal of this project was to determine the genetic basis for quality differences between a modern semidwarf spring wheat cultivar ‘McNeal’ and a historically important standard height cultivar ‘Thatcher’. McNeal is higher yielding with lower grain protein than Thatcher, yet has stronger gluten p...

  3. Genetic, Epigenetic and Environmental Impact on Sex Differences in Social Behavior

    PubMed Central

    Shepard, Kathryn N.; Michopoulos, Vasiliki; Toufexis, Donna J.; Wilson, Mark E.

    2009-01-01

    The field of behavioral neuroendocrinology has generated thousands of studies that indicate differences in brain structure and reactivity to gonadal steroids produce sex-specific patterns of social behavior. However, rapidly emerging evidence shows that genetic polymorphisms and resulting differences in the expression of neuroactive peptides and receptors as well as early life experience and epigenetic changes are important modifiers of social behavior. Furthermore, due to its inherent complexity, the neurochemical mechanisms underlying sex differences in social behavior are usually studied in a tightly regulated laboratory setting rather than in complex environments. Importantly, specific hormones may elicit a range of different behaviors depending on the cues present in these environments. For example, individuals exposed to a psychosocial stressor may respond differently to the effects of a gonadal steroid than those not exposed to chronic stress. The objective of this review is not to re-examine the activational effects of hormones on sex differences in social behavior but rather to consider how genetic and environmental factors modify the effects of hormones on behavior. We will focus on estrogen and its receptors but consideration is also given to the role of androgens. Furthermore, we have limited our discussions to the importance of oxytocin and vasopressin as targets of gonadal steroids and how these effects are modified by genetic and experiential situations. Taken together, the data clearly underscore the need to expand research initiatives to consider gene-environment interactions for better understanding the neurobiology of sex differences in social behavior. PMID:19250945

  4. The human HDL proteome displays high inter-individual variability and is altered dynamically in response to angioplasty-induced atheroma plaque rupture.

    PubMed

    Jorge, Inmaculada; Burillo, Elena; Mesa, Raquel; Baila-Rueda, Lucía; Moreno, Margoth; Trevisan-Herraz, Marco; Silla-Castro, Juan Carlos; Camafeita, Emilio; Ortega-Muñoz, Mariano; Bonzon-Kulichenko, Elena; Calvo, Isabel; Cenarro, Ana; Civeira, Fernando; Vázquez, Jesús

    2014-06-25

    Recent findings support potential roles for HDL in cardiovascular pathophysiology not related to lipid metabolism. We address whether HDL proteome is dynamically altered in atheroma plaque rupture. We used immunoaffinity purification of HDL samples from coronary artery disease patients before and after percutaneous transluminal coronary angioplasty (PTCA), a model of atheroma plaque disruption. Samples were analyzed by quantitative proteomics using stable isotope labeling and results were subjected to statistical analysis of protein variance using a novel algorithm. We observed high protein variability in HDL composition between individuals, indicating that HDL protein composition is highly patient-specific. However, intra-individual protein variances remained at low levels, confirming the reproducibility of the method used for HDL isolation and protein quantification. A systems biology analysis of HDL protein alterations induced by PTCA revealed an increase in two protein clusters that included several apolipoproteins, fibrinogen-like protein 1 and other intracellular proteins, and a decrease in antithrombin-III, annexin A1 and several immunoglobulins. Our results support the concept of HDL as dynamic platforms that donate and receive a variety of molecules and provide an improved methodology to use HDL proteome for the systematic analysis of differences among individuals and the search for cardiovascular biomarkers. Biological significance The HDL proteome is an interesting model of clinical relevance and has been previously described to be dynamically altered in response to pathophysiological conditions and cardiovascular diseases. Our study suggests that interindividual variability of HDL proteome is higher than previously thought and provided the detection of a set of proteins that changed their abundance in response to plaque rupture, supporting the concept of HDL as dynamic platforms that donate and receive a variety of molecules. PMID:24747125

  5. The Location of The Inferior and Superior Temporal Blood Vessels and Inter-Individual Variability of The Retinal Nerve Fiber Layer Thickness

    PubMed Central

    Hood, Donald C.; Salant, Jennifer A.; Arthur, Stella N.; Ritch, Robert; Liebmann, Jeffrey M.

    2009-01-01

    Purpose To determine if adjusting for blood vessel location can decrease the inter-subject variability of retinal nerve fiber (RNFL) thickness measured with optical coherence tomography (OCT). Subjects and Methods One eye of 50 individuals with normal vision was tested with OCT and scanning laser polarimetry (SLP). The SLP and OCT RNFL thickness profiles were determined for a peripapillary circle 3.4 mm in diameter. The midpoints between the superior temporal vein and artery (STva) and the inferior temporal vein and artery (ITva) were determined at the location where the vessels cross the 3.4 mm circle. The average OCT and SLP RNFL thicknesses for quadrants and arcuate sectors of the lower and upper optic disc were obtained before and after adjusting for blood vessel location. This adjustment was done by shifting the RNFL profiles based upon the locations of the STva and ITva relative to the mean locations of all 50 individuals. Results Blood vessel locations ranged over 39° (STva) and 33° (ITva) for the 50 eyes. The location of the leading edge of the OCT and SLP profiles was correlated with the location of the blood vessels for both the superior [r=0.72 (OCT) and 0.72(SLP)] and inferior [r=0.34 and 0.43] temporal vessels. However, the variability in the OCT and SLP thickness measurements showed little change due to shifting. After shifting, the difference in the coefficient of variation ranged from −2.1% (shifted less variable) to +1.7% (unshifted less variable). Conclusion The shape of the OCT and SLP RNFL profiles varied systematically with the location of the superior and inferior superior veins and arteries. However, adjusting for the location of these major temporal blood vessels did not decrease the variability for measures of OCT or SLP RNFL thickness. PMID:19661824

  6. AFLPs Reveal Different Population Genetic Structure under Contrasting Environments in the Marine Snail Nucella lapillus L.

    PubMed Central

    Carro, Belén; Quintela, María; Ruiz, José Miguel; Barreiro, Rodolfo

    2012-01-01

    Dispersal has received growing attention in marine ecology, particularly since evidence obtained with up-to-date techniques challenged the traditional view. The dogwhelk Nucella lapillus L., a sedentary gastropod with direct development, is a good example: dispersal was traditionally assumed to be limited until studies with microsatellites disputed this idea. To shed some light on this controversy, the genetic structure of dogwhelk populations in northwest Spain was investigated with highly polymorphic AFLP markers giving special attention to the influence of hydrodynamic stress. In agreement with the expectations for a poor disperser, our results show a significant genetic structure at regional (<200 km) and areal scales (<15 km). However, the spatial genetic structure varied with wave-exposure in the present case study: IBD was evident under sheltered conditions but absent from the exposed area where genetic differentiation was stronger. Our results provide evidence that differences in wave-exposure can exert a detectable influence on the genetic structure of coastal organisms, even in species without a planktonic larva. PMID:23185435

  7. Cost-Effectiveness Analysis of Different Genetic Testing Strategies for Lynch Syndrome in Taiwan

    PubMed Central

    Chen, Ying-Erh; Kao, Sung-Shuo; Chung, Ren-Hua

    2016-01-01

    Patients with Lynch syndrome (LS) have a significantly increased risk of developing colorectal cancer (CRC) and other cancers. Genetic screening for LS among patients with newly diagnosed CRC aims to identify mutations in the disease-causing genes (i.e., the DNA mismatch repair genes) in the patients, to offer genetic testing for relatives of the patients with the mutations, and then to provide early prevention for the relatives with the mutations. Several genetic tests are available for LS, such as DNA sequencing for MMR genes and tumor testing using microsatellite instability and immunohistochemical analyses. Cost-effectiveness analyses of different genetic testing strategies for LS have been performed in several studies from different countries such as the US and Germany. However, a cost-effectiveness analysis for the testing has not yet been performed in Taiwan. In this study, we evaluated the cost-effectiveness of four genetic testing strategies for LS described in previous studies, while population-specific parameters, such as the mutation rates of the DNA mismatch repair genes and treatment costs for CRC in Taiwan, were used. The incremental cost-effectiveness ratios based on discounted life years gained due to genetic screening were calculated for the strategies relative to no screening and to the previous strategy. Using the World Health Organization standard, which was defined based on Taiwan’s Gross Domestic Product per capita, the strategy based on immunohistochemistry as a genetic test followed by BRAF mutation testing was considered to be highly cost-effective relative to no screening. Our probabilistic sensitivity analysis results also suggest that the strategy has a probability of 0.939 of being cost-effective relative to no screening based on the commonly used threshold of $50,000 to determine cost-effectiveness. To the best of our knowledge, this is the first cost-effectiveness analysis for evaluating different genetic testing strategies for LS

  8. Cost-Effectiveness Analysis of Different Genetic Testing Strategies for Lynch Syndrome in Taiwan.

    PubMed

    Chen, Ying-Erh; Kao, Sung-Shuo; Chung, Ren-Hua

    2016-01-01

    Patients with Lynch syndrome (LS) have a significantly increased risk of developing colorectal cancer (CRC) and other cancers. Genetic screening for LS among patients with newly diagnosed CRC aims to identify mutations in the disease-causing genes (i.e., the DNA mismatch repair genes) in the patients, to offer genetic testing for relatives of the patients with the mutations, and then to provide early prevention for the relatives with the mutations. Several genetic tests are available for LS, such as DNA sequencing for MMR genes and tumor testing using microsatellite instability and immunohistochemical analyses. Cost-effectiveness analyses of different genetic testing strategies for LS have been performed in several studies from different countries such as the US and Germany. However, a cost-effectiveness analysis for the testing has not yet been performed in Taiwan. In this study, we evaluated the cost-effectiveness of four genetic testing strategies for LS described in previous studies, while population-specific parameters, such as the mutation rates of the DNA mismatch repair genes and treatment costs for CRC in Taiwan, were used. The incremental cost-effectiveness ratios based on discounted life years gained due to genetic screening were calculated for the strategies relative to no screening and to the previous strategy. Using the World Health Organization standard, which was defined based on Taiwan's Gross Domestic Product per capita, the strategy based on immunohistochemistry as a genetic test followed by BRAF mutation testing was considered to be highly cost-effective relative to no screening. Our probabilistic sensitivity analysis results also suggest that the strategy has a probability of 0.939 of being cost-effective relative to no screening based on the commonly used threshold of $50,000 to determine cost-effectiveness. To the best of our knowledge, this is the first cost-effectiveness analysis for evaluating different genetic testing strategies for LS in

  9. Why do we differ in number sense? Evidence from a genetically sensitive investigation☆

    PubMed Central

    Tosto, M.G.; Petrill, S.A.; Halberda, J.; Trzaskowski, M.; Tikhomirova, T.N.; Bogdanova, O.Y.; Ly, R.; Wilmer, J.B.; Naiman, D.Q.; Germine, L.; Plomin, R.; Kovas, Y.

    2014-01-01

    Basic intellectual abilities of quantity and numerosity estimation have been detected across animal species. Such abilities are referred to as ‘number sense’. For human species, individual differences in number sense are detectable early in life, persist in later development, and relate to general intelligence. The origins of these individual differences are unknown. To address this question, we conducted the first large-scale genetically sensitive investigation of number sense, assessing numerosity discrimination abilities in 837 pairs of monozygotic and 1422 pairs of dizygotic 16-year-old twin pairs. Univariate genetic analysis of the twin data revealed that number sense is modestly heritable (32%), with individual differences being largely explained by non-shared environmental influences (68%) and no contribution from shared environmental factors. Sex-Limitation model fitting revealed no differences between males and females in the etiology of individual differences in number sense abilities. We also carried out Genome-wide Complex Trait Analysis (GCTA) that estimates the population variance explained by additive effects of DNA differences among unrelated individuals. For 1118 unrelated individuals in our sample with genotyping information on 1.7 million DNA markers, GCTA estimated zero heritability for number sense, unlike other cognitive abilities in the same twin study where the GCTA heritability estimates were about 25%. The low heritability of number sense, observed in this study, is consistent with the directional selection explanation whereby additive genetic variance for evolutionary important traits is reduced. PMID:24696527

  10. Why do we differ in number sense? Evidence from a genetically sensitive investigation.

    PubMed

    Tosto, M G; Petrill, S A; Halberda, J; Trzaskowski, M; Tikhomirova, T N; Bogdanova, O Y; Ly, R; Wilmer, J B; Naiman, D Q; Germine, L; Plomin, R; Kovas, Y

    2014-03-01

    Basic intellectual abilities of quantity and numerosity estimation have been detected across animal species. Such abilities are referred to as 'number sense'. For human species, individual differences in number sense are detectable early in life, persist in later development, and relate to general intelligence. The origins of these individual differences are unknown. To address this question, we conducted the first large-scale genetically sensitive investigation of number sense, assessing numerosity discrimination abilities in 837 pairs of monozygotic and 1422 pairs of dizygotic 16-year-old twin pairs. Univariate genetic analysis of the twin data revealed that number sense is modestly heritable (32%), with individual differences being largely explained by non-shared environmental influences (68%) and no contribution from shared environmental factors. Sex-Limitation model fitting revealed no differences between males and females in the etiology of individual differences in number sense abilities. We also carried out Genome-wide Complex Trait Analysis (GCTA) that estimates the population variance explained by additive effects of DNA differences among unrelated individuals. For 1118 unrelated individuals in our sample with genotyping information on 1.7 million DNA markers, GCTA estimated zero heritability for number sense, unlike other cognitive abilities in the same twin study where the GCTA heritability estimates were about 25%. The low heritability of number sense, observed in this study, is consistent with the directional selection explanation whereby additive genetic variance for evolutionary important traits is reduced. PMID:24696527

  11. Genetic differences among Anopheles vestitipennis subpopulations collected using different methods in Chiapas state, southern México.

    PubMed

    Arredondo-Jiménez, J I; Gimnig, J; Rodríguez, M H; Washino, R K

    1996-09-01

    Biting activity and population genetic studies of the malaria vector Anopheles vestitipennis were conducted in southern México. Three subpopulations were collected from 2 villages; 2 subpopulations were from the same village, one on human bait and one with an animal-baited trap; the third was collected from a cattle corral in the 2nd village (280 km away SSE). The anthropophilic subpopulation had steady activity with 61% of bites occurring before midnight, significantly different from those of the 2 zoophilic subpopulations, which had 78-82% of bites before midnight and 2 biting peaks, one at 1900-2100 h and the other at 0400-0500 h. Isozyme analysis (13 enzymes) of these subpopulations indicated that differences between the 2 sympatric subpopulations (D = 0.07), collected using 2 different methods, were greater than that between the 2 allopatric ones (D = 0.03). These studies suggest the existence of 2 genetically different subpopulations of An. vestitipennis with specific host preferences. PMID:8887216

  12. Different Slopes for Different Folks: Genetic Influences on Growth in Delinquent Peer Association and Delinquency During Adolescence.

    PubMed

    Connolly, Eric J; Schwartz, Joseph A; Nedelec, Joseph L; Beaver, Kevin M; Barnes, J C

    2015-07-01

    An extensive line of research has identified delinquent peer association as a salient environmental risk factor for delinquency, especially during adolescence. While previous research has found moderate-to-strong associations between exposure to delinquent peers and a variety of delinquent behaviors, comparatively less scholarship has focused on the genetic architecture of this association over the course of adolescence. Using a subsample of kinship pairs (N = 2379; 52% female) from the National Longitudinal Survey of Youth-Child and Young Adult Supplement (CNLSY), the present study examined the extent to which correlated individual differences in starting levels and developmental growth in delinquent peer pressure and self-reported delinquency were explained by additive genetic and environmental influences. Results from a series of biometric growth models revealed that 37% of the variance in correlated growth between delinquent peer pressure and self-reported delinquency was explained by additive genetic effects, while nonshared environmental effects accounted for the remaining 63% of the variance. Implications of these findings for interpreting the nexus between peer effects and adolescent delinquency are discussed. PMID:25967897

  13. Induced neural stem cells from distinct genetic backgrounds exhibit different reprogramming status.

    PubMed

    Kim, Sung Min; Lim, Kyung Tae; Kwak, Tae Hwan; Lee, Seung Chan; Im, Jung Hyun; Hali, Sai; In Hwang, Seon; Kim, Dajeong; Hwang, Jeongho; Kim, Kee-Pyo; Chung, Hak-Jae; Kim, Jeong Beom; Ko, Kinarm; Chung, Hyung-Min; Lee, Hoon Taek; Schöler, Hans R; Han, Dong Wook

    2016-03-01

    Somatic cells could be directly converted into induced neural stem cells (iNSCs) by ectopic expression of defined transcription factors. However, the underlying mechanism of direct lineage transition into iNSCs is largely unknown. In this study, we examined the effect of genetic background on the direct conversion process into an iNSC state. The iNSCs from two different mouse strains exhibited the distinct efficiency of lineage conversion as well as clonal expansion. Furthermore, the expression levels of endogenous NSC markers, silencing of transgenes, and in vitro differentiation potential were also different between iNSC lines from different strains. Therefore, our data suggest that the genetic background of starting cells influences the conversion efficiency as well as reprogramming status of directly converted iNSCs. PMID:26930613

  14. Genetic and phytochemical difference between some Indian and Italian plants of Withania somnifera (L.) Dunal.

    PubMed

    Scartezzini, P; Antognoni, F; Conte, L; Maxia, A; Troìa, A; Poli, F

    2007-08-01

    The geographical distribution of Withania somnifera (L.) Dunal is quite wide. However, in Italy, this species is very rare and grows spontaneously only in Sicily and in Sardinia. The PCR-RAPD technique has been utilized in this work to determine the genetic relationship among Sicilian, Sardinian and Indian samples and the HPLC analysis of whitaferin A was used as a marker to evaluate the phytochemical differences. The genetic difference between Indian and Sicilian plants of W. somnifera turned out to be smaller than that between Indian and Sardinian plants of this species. The phytochemical analysis as well showed that the Sardinian specimen strongly differed from the Indian and Sicilian ones in its contents of withaferin A. Our results seem to confirm the hypothesis that the Italian populations of this species may not be indigenous but naturalised. Due to the high withaferin A content of the Sardinian samples, these plants could be used as a source for pharmaceutical purposes. PMID:17680504

  15. Sex Differences in Genetic and Environmental Influences on Longitudinal Change in Functional Ability in Late Adulthood

    PubMed Central

    Ernsth-Bravell, Marie; Pedersen, Nancy L.

    2015-01-01

    Objectives. To determine the extent to which genetic and environmental factors contribute to individual and gender differences in aging of functional ability. Method. Twenty assessments of functional ability are collected as part of the longitudinal Swedish Adoption/Twin Study of Aging from 859 twins aged 50–88 at the first wave. Participants completed up to 6 assessments covering a 19-year period. Factor analysis was used to create 3 factors: flexibility, fine motor skills, and balance. Results. Latent growth curve analysis demonstrated increasing disability and variability after age 70. For flexibility, results indicated significant sex differences in mean change trajectories but no sex differences in components of variance. No sex differences were found for fine motor movement. For balance, there were no sex differences in mean change trajectories; however, there was significant genetic variance for changes in balance in women after age 70 but not for men. Discussion. Although idiosyncratic environmental influences account for a large part of increasing variance, correlated and shared rearing environmental effects were also evident. Thus, both microenvironmental (individual) and macroenvironmental (family and cultural) effects, as well as genetic factors, affect maintenance of functional ability in late adulthood. PMID:24398585

  16. Discovering misattributed paternity in genetic counselling: different ethical perspectives in two countries.

    PubMed

    Tozzo, Pamela; Caenazzo, Luciana; Parker, Michael J

    2014-03-01

    Misattributed paternity or 'false' paternity is when a man is wrongly thought, by himself and possibly by others, to be the biological father of a child. Nowadays, because of the progression of genetics and genomics the possibility of finding misattributed paternity during familial genetic testing has increased. In contrast to other medical information, which pertains primarily to individuals, information obtained by genetic testing and/or pedigree analysis necessarily has implications for other biologically related members in the family. Disclosing or not a misattributed paternity has a number of different biological and social consequences for the people involved. Such an issue presents important ethical and deontological challenges. The debate centres on whether or not to inform the family and, particularly, whom in the family, about the possibility that misattributed paternity might be discovered incidentally, and whether or not it is the duty of the healthcare professional (HCP) to disclose the results and to whom. In this paper, we consider the different perspectives and reported problems, and analyse their cultural, ethical and legal dimensions. We compare the position of HCPs from an Italian and British point of view, particularly their role in genetic counselling. We discuss whether the Oviedo Convention of the Council of Europe (1997) can be seen as a basis for enriching the debate. PMID:23443210

  17. Genetic basis of the difference in alcohol dehydrogenase expression between Drosophila melanogaster and Drosophila simulans.

    PubMed Central

    Laurie, C C; Heath, E M; Jacobson, J W; Thomson, M S

    1990-01-01

    Drosophila melanogaster and its sibling species, Drosophila simulans, differ in expression of the enzyme alcohol dehydrogenase (ADH). Adult melanogaster flies that are homozygous for the Slow allozyme have approximately twice the level of ADH activity and crossreacting material as simulans adults. There is no corresponding difference in ADH mRNA, however, so this difference in ADH protein level is evidently due to a difference in the rate of translation of the two RNAs and/or to a difference in protein stability. Here we report an interspecific gene-transfer experiment, using P-element transformation, to determine whether this expression difference is due to genetic background differences between the species (trans-acting modifiers) or to cis-acting factors within the Adh gene. When the Adh genes from D. melanogaster and D. simulans are put into the same genetic background, there is no detectable difference in their level of expression. The level is relatively high in the melanogaster background and relatively low in the simulans background. Therefore, the interspecific difference in Adh expression is due entirely to trans-acting modifiers, in spite of the many sequence differences between the Adh genes of the two species, which include two amino acid substitutions. PMID:2124699

  18. Evaluation of different genetic procedures for the generation of artificial hybrids in Saccharomyces genus for winemaking.

    PubMed

    Pérez-Través, Laura; Lopes, Christian A; Barrio, Eladio; Querol, Amparo

    2012-05-15

    Several methods based on recombinant DNA techniques have been proposed for yeast strain improvement; however, the most relevant oenological traits depend on a multitude of loci, making these techniques difficult to apply. In this way, hybridization techniques involving two complete genomes became interesting. Natural hybrid strains between different Saccharomyces species have been detected in diverse fermented beverages including wine, cider and beer. These hybrids seem to be better adapted to fluctuating situations typically observed in fermentations due to the acquisition of particular physiological properties of both parental strains. In this work we evaluated the usefulness of three different hybridization methods: spore to spore mating, rare-mating and protoplast fusion for the generation of intra- and inter-specific stable hybrids, being the first report about the comparison of different methods to obtain artificial hybrids to be used in fermentations. Spore to spore mating is an easy but time-consuming method; hybrids generated with this technique could lack some of the industrially relevant traits present in the parental strains because of the segregation occurred during meiosis and spore generation prior to hybridization. Hybrids obtained by protoplast fusion get the complete information of both parents but they are currently considered as genetically modified organisms (GMOs). Finally, hybrids obtained by rare-mating are easily obtained by the optimized methodology described in this work, they originally contain a complete set of chromosomes of both parents and they are not considered as GMOs. Hybrids obtained by means of the three methodological approaches showed a high genetic variability; however, a loss of genetic material was detected in most of them. Based on these results, it became evident that a last crucial aspect to be considered in every hybridization program is the genetic stabilization of recently generated hybrids that guarantee its

  19. Genetic variation in human NPY expression affects stress response and emotion

    PubMed Central

    Zhou, Zhifeng; Zhu, Guanshan; Hariri, Ahmad R.; Enoch, Mary-Anne; Scott, David; Sinha, Rajita; Virkkunen, Matti; Mash, Deborah C.; Lipsky, Robert H.; Hu, Xian-Zhang; Hodgkinson, Colin A.; Xu, Ke; Buzas, Beata; Yuan, Qiaoping; Shen, Pei-Hong; Ferrell, Robert E.; Manuck, Stephen B.; Brown, Sarah M.; Hauger, Richard L.; Stohler, Christian S.; Zubieta, Jon-Kar; Goldman, David

    2009-01-01

    Understanding inter-individual differences in stress response requires the explanation of genetic influences at multiple phenotypic levels, including complex behaviours and the metabolic responses of brain regions to emotional stimuli. Neuropeptide Y (NPY) is anxiolytic1,2 and its release is induced by stress3. NPY is abundantly expressed in regions of the limbic system that are implicated in arousal and in the assignment of emotional valences to stimuli and memories4–6. Here we show that haplotype-driven NPY expression predicts brain responses to emotional and stress challenges and also inversely correlates with trait anxiety. NPY haplotypes predicted levels of NPY messenger RNA in postmortem brain and lymphoblasts, and levels of plasma NPY. Lower haplotype-driven NPY expression predicted higher emotion-induced activation of the amygdala, as well as diminished resiliency as assessed by pain/stress-induced activations of endogenous opioid neurotransmission in various brain regions. A single nucleotide polymorphism (SNP rs16147) located in the promoter region alters NPY expression in vitro and seems to account for more than half of the variation in expression in vivo. These convergent findings are consistent with the function of NPY as an anxiolytic peptide and help to explain inter-individual variation in resiliency to stress, a risk factor for many diseases. PMID:18385673

  20. Genetic variation in human NPY expression affects stress response and emotion.

    PubMed

    Zhou, Zhifeng; Zhu, Guanshan; Hariri, Ahmad R; Enoch, Mary-Anne; Scott, David; Sinha, Rajita; Virkkunen, Matti; Mash, Deborah C; Lipsky, Robert H; Hu, Xian-Zhang; Hodgkinson, Colin A; Xu, Ke; Buzas, Beata; Yuan, Qiaoping; Shen, Pei-Hong; Ferrell, Robert E; Manuck, Stephen B; Brown, Sarah M; Hauger, Richard L; Stohler, Christian S; Zubieta, Jon-Kar; Goldman, David

    2008-04-24

    Understanding inter-individual differences in stress response requires the explanation of genetic influences at multiple phenotypic levels, including complex behaviours and the metabolic responses of brain regions to emotional stimuli. Neuropeptide Y (NPY) is anxiolytic and its release is induced by stress. NPY is abundantly expressed in regions of the limbic system that are implicated in arousal and in the assignment of emotional valences to stimuli and memories. Here we show that haplotype-driven NPY expression predicts brain responses to emotional and stress challenges and also inversely correlates with trait anxiety. NPY haplotypes predicted levels of NPY messenger RNA in post-mortem brain and lymphoblasts, and levels of plasma NPY. Lower haplotype-driven NPY expression predicted higher emotion-induced activation of the amygdala, as well as diminished resiliency as assessed by pain/stress-induced activations of endogenous opioid neurotransmission in various brain regions. A single nucleotide polymorphism (SNP rs16147) located in the promoter region alters NPY expression in vitro and seems to account for more than half of the variation in expression in vivo. These convergent findings are consistent with the function of NPY as an anxiolytic peptide and help to explain inter-individual variation in resiliency to stress, a risk factor for many diseases. PMID:18385673

  1. Genetic diversity and genetic structure of different types of natural populations in Osmanthus fragrans Lour. and the relationships with sex ratio, population structure, and geographic isolation.

    PubMed

    Hu, Shaoqing; Wu, Shuai; Wang, Yiguang; Zhao, Hongbo; Zhang, Yuanyan

    2014-01-01

    Osmanthus fragrans Lour., an evergreen small tree, has the rare sexual system of androdioecy (coexistence of males and hermaphrodites), once with wide-spread natural distribution in the areas of the South Yangzi river basin. However, due to excessive human utilization, natural distribution became fragmented and the number and size of natural populations reduced sharply. With four different types of natural populations from the same region as research object, we aim to provide a comparative analysis on the relationships among genetic diversity, sexual system, population structure and size, and geographic isolation by ISSR. In genetic parameters of N e , H e , and I, the LQGC population had the highest value and the LQZGQ population had the lowest value. These indicated that LQGC population showed the highest genetic diversity, followed by QDH and JN population, and LQZGQ population exhibited the lowest genetic diversity. Genetic diversity in populations is closely related to population structure, reproduction mode, and sex ratio. However, there seems to be no obvious correlation between genetic diversity and population size. The results of AMOVA showed that genetic variations mostly occurred within populations. It indicates that no significant genetic differentiation among populations occurs, and geographic isolation has no significant effect on genetic diversity. PMID:25436228

  2. Genetic Diversity and Genetic Structure of Different Types of Natural Populations in Osmanthus fragrans Lour. and the Relationships with Sex Ratio, Population Structure, and Geographic Isolation

    PubMed Central

    Hu, Shaoqing; Wu, Shuai; Wang, Yiguang; Zhang, Yuanyan

    2014-01-01

    Osmanthus fragrans Lour., an evergreen small tree, has the rare sexual system of androdioecy (coexistence of males and hermaphrodites), once with wide-spread natural distribution in the areas of the South Yangzi river basin. However, due to excessive human utilization, natural distribution became fragmented and the number and size of natural populations reduced sharply. With four different types of natural populations from the same region as research object, we aim to provide a comparative analysis on the relationships among genetic diversity, sexual system, population structure and size, and geographic isolation by ISSR. In genetic parameters of Ne, He, and I, the LQGC population had the highest value and the LQZGQ population had the lowest value. These indicated that LQGC population showed the highest genetic diversity, followed by QDH and JN population, and LQZGQ population exhibited the lowest genetic diversity. Genetic diversity in populations is closely related to population structure, reproduction mode, and sex ratio. However, there seems to be no obvious correlation between genetic diversity and population size. The results of AMOVA showed that genetic variations mostly occurred within populations. It indicates that no significant genetic differentiation among populations occurs, and geographic isolation has no significant effect on genetic diversity. PMID:25436228

  3. Human immunodeficiency virus type 1 genetic evolution in children with different rates of development of disease.

    PubMed Central

    Ganeshan, S; Dickover, R E; Korber, B T; Bryson, Y J; Wolinsky, S M

    1997-01-01

    The rate of development of disease varies considerably among human immunodeficiency virus type 1 (HIV-1)-infected children. The reasons for these observed differences are not clearly understood but most probably depend on the dynamic interplay between the HIV-1 quasispecies virus population and the immune constraints imposed by the host. To study the relationship between disease progression and genetic diversity, we analyzed the evolution of viral sequences within six perinatally infected children by examining proviral sequences spanning the C2 through V5 regions of the viral envelope gene by PCR of blood samples obtained at sequential visits. PCR product DNAs from four sample time points per child were cloned, and 10 to 13 clones from each sample were sequenced. Greater genetic distances relative to the time of infection were found for children with low virion-associated RNA burdens and slow progression to disease relative to those found for children with high virion-associated RNA burdens and rapid progression to disease. The greater branch lengths observed in the phylogenetic reconstructions correlated with a higher accumulation rate of nonsynonymous base substitutions per potential nonsynonymous site, consistent with positive selection for change rather than a difference in replication kinetics. Viral sequences from children with slow progression to disease also showed a tendency to form clusters that associated with different sampling times. These progressive shifts in the viral population were not found in viral sequences from children with rapid progression to disease. Therefore, despite the HIV-1 quasispecies being a diverse, rapidly evolving, and competing population of genetic variants, different rates of genetic evolution could be found under different selective constraints. These data suggest that the evolutionary dynamics exhibited by the HIV-1 quasispecies virus populations are compatible with a Darwinian system evolving under the constraints of

  4. Differences in foraging ecology align with genetically divergent ecotypes of a highly mobile marine top predator.

    PubMed

    Jeglinski, Jana W E; Wolf, Jochen B W; Werner, Christiane; Costa, Daniel P; Trillmich, Fritz

    2015-12-01

    Foraging differentiation within a species can contribute to restricted gene flow between ecologically different groups, promoting ecological speciation. Galapagos sea lions (Zalophus wollebaeki) show genetic and morphological divergence between the western and central archipelago, possibly as a result of an ecologically mediated contrast in the marine habitat. We use global positioning system (GPS) data, time-depth recordings (TDR), stable isotope and scat data to compare foraging habitat characteristics, diving behaviour and diet composition of Galapagos sea lions from a western and a central colony. We consider both juvenile and adult life stages to assess the potential role of ontogenetic shifts that can be crucial in shaping foraging behaviour and habitat choice for life. We found differences in foraging habitat use, foraging style and diet composition that aligned with genetic differentiation. These differences were consistent between juvenile and adult sea lions from the same colony, overriding age-specific behavioural differences. Our study contributes to an understanding of the complex interaction of ecological condition, plastic behavioural response and genetic make-up of interconnected populations. PMID:26307593

  5. Genetic Differences Between Humans and Great Apes -- Implications for the Evolution of Humans

    NASA Astrophysics Data System (ADS)

    Varki, Ajit

    2004-06-01

    At the level of individual protein sequences, humans are 97-100% identical to the great apes, our closest evolutionary relatives. The evolution of humans (and of human intelligence) from a common ancestor with the chimpanzee and bonobo involved many steps, influenced by interactions amongst factors of genetic, developmental, ecological, microbial, climatic, behavioral, cultural and social origin. The genetic factors can be approached by direct comparisons of human and great ape genomes, genes and gene products, and by elucidating biochemical and biological consequences of any differences found. We have discovered multiple genetic and biochemical differences between humans and great apes, particularly with respect to a family of cell surface molecules called sialic acids, as well as in the metabolism of thyroid hormones. The hormone differences have potential consequences for human brain development. The differences in sialic acid biology have multiple implications for the human condition, ranging from susceptibility or resistance to microbial pathogens, effects on endogenous receptors in the immune system, and potential effects on placental signaling, expression of oncofetal antigens in cancers, consequences of dietary intake of animal foods, and development of the mammalian brain.

  6. Comparison of mineral resources calculation methods for different genetic types of gravel and sand deposits

    NASA Astrophysics Data System (ADS)

    Patashova, T.

    2009-04-01

    Calculation of mineral resources and their proper assessment is relevant, since the stock of resources determines the economic independence of the state. I would like present the work wherein discusses gravel and sand deposits of different genetic type (kames, eskers, marginal glaciofluvial ridges, sandurs, glaciofluvial deltas and redrifted glaciofluvial aeolian formations). Their geological structure and formation conditions have been assessed; quality characteristics of mineral resources have been analysed; calculation of resources has been performed by applying most popular resources calculating methods used in Lithuania up to now, such as those of geological blocks, profiles and isolines, as well as the up-to-date GRID method created on the basis of triangle method in GIS environment. Comparison of resources assessed by different methods has revealed their advantages and disadvantages, their availability subject to deposits‘genetic types.

  7. [Genetic diversity and relatedness in different generations of the Siberian crane (Grus leucogeranus Pallas) captive population].

    PubMed

    Mudrik, E A; Kashentseva, T A; Postel'nykh, K A; Nosachenko, G V; Politov, D V

    2014-11-01

    Eight variable microsatellite loci were analyzed in terms of studying the genetic structure of different generations of a captive population of a rare endemic Russian species, the Siberian crane (Grus leucogeranus Pallas). It was shown that the founding population of natural origin (15 birds) is characterized by high genetic diversity (N(A) = 6.625, H(O) = 0.767, H(E) = 0.731) and a lack of relatedness (R = -0.079). In the total sample of descendents of the founders (122 individuals from generations F1, F1/F2, F,/F3, F2, F2/F3), this characteristic level of genetic variation was retained; however, we observed a decrease in allelic richness in some generations (F1/F2, F1/F3, F2). We found a low level of relatedness inthe sample of descendents of the founders (F1, F1/F2, F1/F3), while the relatedness was maximal (R = 0.302) in the first-generation descendents of the breeders. A small sample of breeders related to each other of generations F1 and F2 (eight birds) does not represent the entire gene pool of the founders of the Siberian Crane captive population. In view of this, we discuss the need to form a new genetically heterogeneous generation of breeders that would also include Siberian Cranes from the virtually extinct Western Siberian population. PMID:25739288

  8. Genome-Wide Investigation of Multifocal and Unifocal Prostate Cancer—Are They Genetically Different?

    PubMed Central

    Ibeawuchi, Chinyere; Schmidt, Hartmut; Voss, Reinhard; Titze, Ulf; Abbas, Mahmoud; Neumann, Joerg; Eltze, Elke; Hoogland, Agnes Marije; Jenster, Guido; Brandt, Burkhard; Semjonow, Axel

    2013-01-01

    Prostate cancer is widely observed to be biologically heterogeneous. Its heterogeneity is manifested histologically as multifocal prostate cancer, which is observed more frequently than unifocal prostate cancer. The clinical and prognostic significance of either focal cancer type is not fully established. To investigate prostate cancer heterogeneity, the genetic profiles of multifocal and unifocal prostate cancers were compared. Here, we report observations deduced from tumor-tumor comparison of copy number alteration data of both focal categories. Forty-one fresh frozen prostate cancer foci from 14 multifocal prostate cancers and eight unifocal prostate cancers were subjected to copy number variation analysis with the Affymetrix SNP 6.0 microarray tool. With the investigated cases, tumors obtained from a single prostate exhibited different genetic profiles of variable degrees. Further comparison identified no distinct genetic pattern or signatures specific to multifocal or unifocal prostate cancer. Our findings suggest that samples obtained from multiple sites of a single unifocal prostate cancer show as much genetic heterogeneity and variability as separate tumors obtained from a single multifocal prostate cancer. PMID:23736690

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

    PubMed Central

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

    2010-01-01

    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. PMID:21268289

  10. Optimization of the genetic algorithm of jointly fitting different types of X-ray scattering curves

    SciTech Connect

    Sutyrin, A. G.; Imamov, R. M.

    2011-01-15

    A method for jointly processing X-ray scattering data of different types is developed. It is shown that, by optimizing the genetic algorithm of the joint solution of the inverse problem of X-ray diffractometry and reflectometry, one can reduce the amount of calculations and reliably determine the parameters of layers in the structure under study, even when the information about them is a priori limited.

  11. Virulence Differences among Melissococcus plutonius Strains with Different Genetic Backgrounds in Apis mellifera Larvae under an Improved Experimental Condition.

    PubMed

    Nakamura, Keiko; Yamazaki, Yuko; Shiraishi, Akiyo; Kobayashi, Sota; Harada, Mariko; Yoshiyama, Mikio; Osaki, Makoto; Okura, Masatoshi; Takamatsu, Daisuke

    2016-01-01

    European foulbrood (EFB) caused by Melissococcus plutonius is an important bacterial disease of honeybee larvae. M. plutonius strains can be grouped into three genetically distinct groups (CC3, CC12 and CC13). Because EFB could not be reproduced in artificially reared honeybee larvae by fastidious strains of CC3 and CC13 previously, we investigated a method to improve experimental conditions using a CC3 strain and found that infection with a potassium-rich diet enhanced proliferation of the fastidious strain in larvae at the early stage of infection, leading to the appearance of clear clinical symptoms. Further comparison of M. plutonius virulence under the conditions revealed that the representative strain of CC12 was extremely virulent and killed all tested bees before pupation, whereas the CC3 strain was less virulent than the CC12 strain, and a part of the infected larvae pupated. In contrast, the tested CC13 strain was avirulent, and as with the non-infected control group, most of the infected brood became adult bees, suggesting differences in the insect-level virulence among M. plutonius strains with different genetic backgrounds. These strains and the improved experimental infection method to evaluate their virulence will be useful tools for further elucidation of the pathogenic mechanisms of EFB. PMID:27625313

  12. Genetic analysis of reciprocal differences in the inheritance of in vitro characters in pearl millet.

    PubMed

    Satyavathi, Valluri V; Manga, V; Rao, Muktinutalapati V Subba; Chittibabu, Malladi

    2016-03-01

    Reciprocal differences persist in nature because of the unequal contribution of cytoplasmic determinants from male and female gametes to the zygote. The inheritance of genetic differences is an important factor that influences various traits, including somatic embryogenesis and regeneration in vitro. In this report, we estimate the cytoplasmic and maternal effects in pearl millet and their adequacy in describing the observed reciprocal differences based on an in depth study of the parents, F2s and reciprocal backcross progenies needed for fitting genetical models. Our study revealed that of the two characters examined, embryogenic callus quantity and regeneration frequency, the former showed a greater proportion of cytoplasmic nuclear interaction whereas the latter showed a greater role of nuclear factors. Additive-maternal effects influenced total callus quantity and dominance-maternal effects influenced total callus quantity, embryogenic callus quantity and regeneration frequency. Dwarfing was associated with the production of large quantities of embryogenic callus that had visually recognizable characteristics. The phenotypic nature of dwarf parents (green dwarf with long narrow leaves) with a genetic basis for a given character controlled by nuclear and cytoplasmic determinants can be exploited for other breeding programs. PMID:27007899

  13. Genetic analysis of reciprocal differences in the inheritance of in vitro characters in pearl millet

    PubMed Central

    Satyavathi, Valluri V; Manga, V.; Rao, Muktinutalapati V. Subba; Chittibabu, Malladi

    2016-01-01

    Abstract Reciprocal differences persist in nature because of the unequal contribution of cytoplasmic determinants from male and female gametes to the zygote. The inheritance of genetic differences is an important factor that influences various traits, including somatic embryogenesis and regeneration in vitro. In this report, we estimate the cytoplasmic and maternal effects in pearl millet and their adequacy in describing the observed reciprocal differences based on an in depth study of the parents, F2s and reciprocal backcross progenies needed for fitting genetical models. Our study revealed that of the two characters examined, embryogenic callus quantity and regeneration frequency, the former showed a greater proportion of cytoplasmic nuclear interaction whereas the latter showed a greater role of nuclear factors. Additive-maternal effects influenced total callus quantity and dominance-maternal effects influenced total callus quantity, embryogenic callus quantity and regeneration frequency. Dwarfing was associated with the production of large quantities of embryogenic callus that had visually recognizable characteristics. The phenotypic nature of dwarf parents (green dwarf with long narrow leaves) with a genetic basis for a given character controlled by nuclear and cytoplasmic determinants can be exploited for other breeding programs. PMID:27007899

  14. Genetic characterization of Bombyx mori (Lepidoptera: Bombycidae) breeding and hybrid lines with different geographic origins.

    PubMed

    Furdui, Emilia M; Mărghitaş, Liviu A; Dezmirean, Daniel S; Paşca, Ioan; Pop, Iulia F; Erler, Silvio; Schlüns, Ellen A

    2014-01-01

    The domesticated silkworm Bombyx mori L. comprises a large number of geographical breeds and hybrid lines. Knowing the genetic structure of those may provide information to improve the conservation of commercial lines by estimating inbreeding over generations and the consequences of excessive use of those lineages. Here, we analyzed the genetic diversity of seven breeds and eight hybrid lines from Eastern Europe and Asia using highly polymorphic microsatellites markers to determine its genetical impact on their use in global breeding programs. No consistent pattern of deviation from Hardy-Weinberg equilibrium was found for most breed and hybrids; and the absence of a linkage disequilibrium also suggests that the strains are in equilibrium. A principal coordinate analysis revealed a clear separation of two silkworm breeds from the rest: one (IBV) originated from India and the other one (RG90) from Romania/Japan. The tendency of the other breeds from different geographic origins to cluster together in a general mix might be due to similar selection pressures (climate and anthropogenic factors) in different geographic locations. Phylogenetic analyses grouped the different silkworm breeds but not the hybrids according to their geographic origin and confirmed the pattern found in the principal coordinate analysis. PMID:25502023

  15. Genetics

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Maintaining genetic variation in wild populations of Arctic organisms is fundamental to the long-term persistence of high latitude biodiversity. Variability is important because it provides options for species to respond to changing environmental conditions and novel challenges such as emerging path...

  16. Genetics

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The genus Capsicum represents one of several well characterized Solanaceous genera. A wealth of classical and molecular genetics research is available for the genus. Information gleaned from its cultivated relatives, tomato and potato, provide further insight for basic and applied studies. Early ...

  17. Social and emotional processing in Prader-Willi syndrome: genetic subtype differences

    PubMed Central

    2013-01-01

    Background People with Prader-Willi syndrome (PWS) demonstrate social dysfunction and increased risk of autism spectrum disorder, especially those with the maternal uniparental disomy (mUPD) versus paternal deletion genetic subtype. This study compared the neural processing of social (faces) and nonsocial stimuli, varying in emotional valence, across genetic subtypes in 24 adolescents and adults with PWS. Methods Upright and inverted faces, and nonsocial objects with positive and negative emotional valence were presented to participants with PWS in an oddball paradigm with smiling faces serving as targets. Behavioral and event-related potential (ERP) data were recorded. Results There were no genetic subtype group differences in accuracy, and all participants performed above chance level. ERP responses revealed genetic subtype differences in face versus object processing. In those with deletions, the face-specific posterior N170 response varied in size for face stimuli versus inverted faces versus nonsocial objects. Persons with mUPD generated N170 of smaller amplitude and showed no stimulus differentiation. Brain responses to emotional content did not vary by subtype. All participants elicited larger posterior and anterior late positive potential responses to positive objects than to negative objects. Emotion-related differences in response to faces were limited to inverted faces only in the form of larger anterior late positive potential amplitudes to negative emotions over the right hemisphere. Detection of the target smiling faces was evident in the increased amplitude of the frontal and central P3 responses but only for inverted smiling faces. Conclusion Persons with the mUPD subtype of PWS may show atypical face versus object processes, yet both subtypes demonstrated potentially altered processing, attention to and/or recognition of faces and their expressions. PMID:23536992

  18. Regional differences in seasonal timing of rainfall discriminate between genetically distinct East African giraffe taxa.

    PubMed

    Thomassen, Henri A; Freedman, Adam H; Brown, David M; Buermann, Wolfgang; Jacobs, David K

    2013-01-01

    Masai (Giraffa tippelskirchi), Reticulated (G. reticulata) and Rothschild's (G. camelopardalis) giraffe lineages in East Africa are morphologically and genetically distinct, yet in Kenya their ranges abut. This raises the question of how divergence is maintained among populations of a large mammal capable of long-distance travel, and which readily hybridize in zoos. Here we test four hypotheses concerning the maintenance of the phylogeographic boundaries among the three taxa: 1) isolation-by-distance; 2) physical barriers to dispersal; 3) general habitat differences resulting in habitat segregation; or 4) regional differences in the seasonal timing of rainfall, and resultant timing of browse availability. We used satellite remotely sensed and climate data to characterize the environment at the locations of genotyped giraffes. Canonical variate analysis, random forest algorithms, and generalized dissimilarity modelling were employed in a landscape genetics framework to identify the predictor variables that best explained giraffes' genetic divergence. We found that regional differences in the timing of precipitation, and resulting green-up associated with the abundance of browse, effectively discriminate between taxa. Local habitat conditions, topographic and human-induced barriers, and geographic distance did not aid in discriminating among lineages. Our results suggest that selection associated with regional timing of events in the annual climatic cycle may help maintain genetic and phenotypic divergence in giraffes. We discuss potential mechanisms of maintaining divergence, and suggest that synchronization of reproduction with seasonal rainfall cycles that are geographically distinct may contribute to reproductive isolation. Coordination of weaning with green-up cycles could minimize the costs of lactation and predation on the young. Our findings are consistent with theory and empirical results demonstrating the efficacy of seasonal or phenologically dictated

  19. Regional Differences in Seasonal Timing of Rainfall Discriminate between Genetically Distinct East African Giraffe Taxa

    PubMed Central

    Thomassen, Henri A.; Freedman, Adam H.; Brown, David M.; Buermann, Wolfgang; Jacobs, David K.

    2013-01-01

    Masai (Giraffa tippelskirchi), Reticulated (G. reticulata) and Rothschild's (G. camelopardalis) giraffe lineages in East Africa are morphologically and genetically distinct, yet in Kenya their ranges abut. This raises the question of how divergence is maintained among populations of a large mammal capable of long-distance travel, and which readily hybridize in zoos. Here we test four hypotheses concerning the maintenance of the phylogeographic boundaries among the three taxa: 1) isolation-by-distance; 2) physical barriers to dispersal; 3) general habitat differences resulting in habitat segregation; or 4) regional differences in the seasonal timing of rainfall, and resultant timing of browse availability. We used satellite remotely sensed and climate data to characterize the environment at the locations of genotyped giraffes. Canonical variate analysis, random forest algorithms, and generalized dissimilarity modelling were employed in a landscape genetics framework to identify the predictor variables that best explained giraffes' genetic divergence. We found that regional differences in the timing of precipitation, and resulting green-up associated with the abundance of browse, effectively discriminate between taxa. Local habitat conditions, topographic and human-induced barriers, and geographic distance did not aid in discriminating among lineages. Our results suggest that selection associated with regional timing of events in the annual climatic cycle may help maintain genetic and phenotypic divergence in giraffes. We discuss potential mechanisms of maintaining divergence, and suggest that synchronization of reproduction with seasonal rainfall cycles that are geographically distinct may contribute to reproductive isolation. Coordination of weaning with green-up cycles could minimize the costs of lactation and predation on the young. Our findings are consistent with theory and empirical results demonstrating the efficacy of seasonal or phenologically dictated

  20. Genetic, environmental and stochastic factors in monozygotic twin discordance with a focus on epigenetic differences.

    PubMed

    Czyz, Witold; Morahan, Julia M; Ebers, George C; Ramagopalan, Sreeram V

    2012-01-01

    Genetic-epidemiological studies on monozygotic (MZ) twins have been used for decades to tease out the relative contributions of genes and the environment to a trait. Phenotypic discordance in MZ twins has traditionally been ascribed to non-shared environmental factors acting after birth, however recent data indicate that this explanation is far too simple. In this paper, we review other reasons for discordance, including differences in the in utero environment, genetic mosaicism, and stochastic factors, focusing particularly on epigenetic discordance. Epigenetic differences are gaining increasing recognition. Although it is clear that in specific cases epigenetic alterations provide a causal factor in disease etiology, the overall significance of epigenetics in twin discordance remains unclear. It is also challenging to determine the causality and relative contributions of environmental, genetic, and stochastic factors to epigenetic variability. Epigenomic profiling studies have recently shed more light on the dynamics of temporal methylation change and methylome heritability, yet have not given a definite answer regarding their relevance to disease, because of limitations in establishing causality. Here, we explore the subject of epigenetics as another component in human phenotypic variability and its links to disease focusing particularly on evidence from MZ twin studies. PMID:22898292

  1. Genetic, environmental and stochastic factors in monozygotic twin discordance with a focus on epigenetic differences

    PubMed Central

    2012-01-01

    Genetic-epidemiological studies on monozygotic (MZ) twins have been used for decades to tease out the relative contributions of genes and the environment to a trait. Phenotypic discordance in MZ twins has traditionally been ascribed to non-shared environmental factors acting after birth, however recent data indicate that this explanation is far too simple. In this paper, we review other reasons for discordance, including differences in the in utero environment, genetic mosaicism, and stochastic factors, focusing particularly on epigenetic discordance. Epigenetic differences are gaining increasing recognition. Although it is clear that in specific cases epigenetic alterations provide a causal factor in disease etiology, the overall significance of epigenetics in twin discordance remains unclear. It is also challenging to determine the causality and relative contributions of environmental, genetic, and stochastic factors to epigenetic variability. Epigenomic profiling studies have recently shed more light on the dynamics of temporal methylation change and methylome heritability, yet have not given a definite answer regarding their relevance to disease, because of limitations in establishing causality. Here, we explore the subject of epigenetics as another component in human phenotypic variability and its links to disease focusing particularly on evidence from MZ twin studies. PMID:22898292

  2. Comparative proteomic analysis of genetically modified maize grown under different agroecosystems conditions in Brazil

    PubMed Central

    2013-01-01

    Background Profiling technologies allow the simultaneous measurement and comparison of thousands of cell components without prior knowledge of their identity. In the present study, we used two-dimensional gel electrophoresis combined with mass spectrometry to evaluate protein expression of Brazilian genetically modified maize hybrid grown under different agroecosystems conditions. To this effect, leaf samples were subjected to comparative analysis using the near-isogenic non-GM hybrid as the comparator. Results In the first stage of the analysis, the main sources of variation in the dataset were identified by using Principal Components Analysis which correlated most of the variation to the different agroecosystems conditions. Comparative analysis within each field revealed a total of thirty two differentially expressed proteins between GM and non-GM samples that were identified and their molecular functions were mainly assigned to carbohydrate and energy metabolism, genetic information processing and stress response. Conclusions To the best of our knowledge this study represents the first evidence of protein identities with differentially expressed isoforms in Brazilian MON810 genetic background hybrid grown under field conditions. As global databases on outputs from “omics” analysis become available, these could provide a highly desirable benchmark for safety assessments. PMID:24304660

  3. Genetic Structure of Natural Populations of Escherichia coli in Wild Hosts on Different Continents

    PubMed Central

    Souza, Valeria; Rocha, Martha; Valera, Aldo; Eguiarte, Luis E.

    1999-01-01

    Current knowledge of genotypic and phenotypic diversity in the species Escherichia coli is based almost entirely on strains recovered from humans or zoo animals. In this study, we analyzed a collection of 202 strains obtained from 81 mammalian species representing 39 families and 14 orders in Australia and the Americas, as well as several reference strains; we also included a strain from a reptile and 10 from different families of birds collected in Mexico. The strains were characterized genotypically by multilocus enzyme electrophoresis (MLEE) and phenotypically by patterns of sugar utilization, antibiotic resistance, and plasmid profile. MLEE analysis yielded an estimated genetic diversity (H) of 0.682 for 11 loci. The observed genetic diversity in this sample is the greatest yet reported for E. coli. However, this genetic diversity is not randomly distributed; geographic effects and host taxonomic group accounted for most of the genetic differentiation. The genetic relationship among the strains showed that they are more associated by origin and host order than is expected by chance. In a dendrogram, the ancestral cluster includes primarily strains from Australia and ECOR strains from groups B and C. The most differentiated E. coli in our analysis are strains from Mexican carnivores and strains from humans, including those in the ECOR group A. The kinds and numbers of sugars utilized by the strains varied by host taxonomic group and country of origin. Strains isolated from bats were found to exploit the greatest range of sugars, while those from primates utilized the fewest. Toxins are more frequent in strains from rodents from both continents than in any other taxonomic group. Strains from Mexican wild mammals were, on average, as resistant to antibiotics as strains from humans in cities. On average, the Australian strains presented a lower antibiotic resistance than the Mexican strains. However, strains recovered from hosts in cities carried significantly more

  4. Mapping genetic variants underlying differences in the central nitrogen metabolism in fermenter yeasts.

    PubMed

    Jara, Matías; Cubillos, Francisco A; García, Verónica; Salinas, Francisco; Aguilera, Omayra; Liti, Gianni; Martínez, Claudio

    2014-01-01

    Different populations within a species represent a rich reservoir of allelic variants, corresponding to an evolutionary signature of withstood environmental constraints. Saccharomyces cerevisiae strains are widely utilised in the fermentation of different kinds of alcoholic beverages, such as, wine and sake, each of them derived from must with distinct nutrient composition. Importantly, adequate nitrogen levels in the medium are essential for the fermentation process, however, a comprehensive understanding of the genetic variants determining variation in nitrogen consumption is lacking. Here, we assessed the genetic factors underlying variation in nitrogen consumption in a segregating population derived from a cross between two main fermenter yeasts, a Wine/European and a Sake isolate. By linkage analysis we identified 18 main effect QTLs for ammonium and amino acids sources. Interestingly, majority of QTLs were involved in more than a single trait, grouped based on amino acid structure and indicating high levels of pleiotropy across nitrogen sources, in agreement with the observed patterns of phenotypic co-variation. Accordingly, we performed reciprocal hemizygosity analysis validating an effect for three genes, GLT1, ASI1 and AGP1. Furthermore, we detected a widespread pleiotropic effect on these genes, with AGP1 affecting seven amino acids and nine in the case of GLT1 and ASI1. Based on sequence and comparative analysis, candidate causative mutations within these genes were also predicted. Altogether, the identification of these variants demonstrate how Sake and Wine/European genetic backgrounds differentially consume nitrogen sources, in part explaining independently evolved preferences for nitrogen assimilation and representing a niche of genetic diversity for the implementation of practical approaches towards more efficient strains for nitrogen metabolism. PMID:24466135

  5. Phylogenetic features of hemagglutin gene in canine distemper virus strains from different genetic lineages.

    PubMed

    Liao, Peng; Guo, Li; Wen, Yongjun; Yang, Yangling; Cheng, Shipeng

    2015-01-01

    In the present study, the genotype of two Canine distemper virus (CDV) strains, namely, ZJJ-SD and ZJJ-LN, were investigated, based on the whole hemagglutinin (HA) gene. The CDV strains were obtained from two foxes in Shandong Province and Liaoning Province in 2011. Phylogenetic analyses were carried out for 260 CDV strains worldwide, and a statistical analysis was performed in the amino acid substitutions at positions 530 and 549 of the HA protein. Phylogenetic analyses revealed that the two strains, ZJJ-SD and ZJJ-LN, belonged to the CDV Asia I lineage. Site 530 of HA protein was found to be relatively conserved within CDV lineages in different host species by combining the genetic sequence data with the published data from 260 CDV strains worldwide. The data analysis showed a bias toward the predicted substitution Y549H for the non-dog strains in Asia I and Europe lineages. The ratio of site 549 genetic drift in the HA gene were significantly different between dogs and non-dogs in the two lineages. The strain ZJJ-SD, from wild canid, has an Y549H substitution. It is one of three Y549H substitution for wild canids in Asia I lineages. Site 530 of HA protein was not immediately relative to CDV genetic drift from dogs to non-dogs. Statistical analysis indicated that non-dog strains have a high probability to contain Y549H than dog strains in Asia I and Europe lineages. Thus, site 549 is considered important in genetic drift from dogs to non-dogs, at least in Asia I and Europe lineages. PMID:26131292

  6. Blue eyes in lemurs and humans: same phenotype, different genetic mechanism.

    PubMed

    Bradley, Brenda J; Pedersen, Anja; Mundy, Nicholas I

    2009-06-01

    Almost all mammals have brown or darkly-pigmented eyes (irises), but among primates, there are some prominent blue-eyed exceptions. The blue eyes of some humans and lemurs are a striking example of convergent evolution of a rare phenotype on distant branches of the primate tree. Recent work on humans indicates that blue eye color is associated with, and likely caused by, a single nucleotide polymorphism (rs12913832) in an intron of the gene HERC2, which likely regulates expression of the neighboring pigmentation gene OCA2. This raises the immediate question of whether blue eyes in lemurs might have a similar genetic basis. We addressed this by sequencing the homologous genetic region in the blue-eyed black lemur (Eulemur macaco flavifrons; N = 4) and the closely-related black lemur (Eulemur macaco macaco; N = 4), which has brown eyes. We then compared a 166-bp segment corresponding to and flanking the human eye-color-associated region in these lemurs, as well as other primates (human, chimpanzee, orangutan, macaque, ring-tailed lemur, mouse lemur). Aligned sequences indicated that this region is strongly conserved in both Eulemur macaco subspecies as well as the other primates (except blue-eyed humans). Therefore, it is unlikely that this regulatory segment plays a major role in eye color differences among lemurs as it does in humans. Although convergent phenotypes can sometimes come about via the same or similar genetic changes occurring independently, this does not seem to be the case here, as we have shown that the genetic basis of blue eyes in lemurs differs from that of humans. PMID:19278018

  7. Genetic potential of common bean progenies selected for crude fiber content obtained through different breeding methods.

    PubMed

    Júnior, V A P; Melo, P G S; Pereira, H S; Bassinello, P Z; Melo, L C

    2015-01-01

    Gastrointestinal health is of great importance due to the increasing consumption of functional foods, especially those concern-ing diets rich in fiber content. The common bean has been valorized as a nutritious food due to its appreciable fiber content and the fact that it is consumed in many countries. The current study aimed to evaluate and compare the genetic potential of common bean progenies of the carioca group, developed through different breeding methods, for crude fiber content. The progenies originated through hybridization of two advanced strains, CNFC 7812 and CNFC 7829, up to the F7 generation using three breeding methods: bulk-population, bulk within F2 families, and single seed descent. Fifteen F8 progenies were evaluated in each method, as well as two check cultivars and both parents, us-ing a 7 x 7 simple lattice design, with experimental plots comprised of two 4-m long rows. Field trials were conducted in eleven environments encompassing four Brazilian states and three different sowing times during 2009 and 2010. Estimates of genetic parameters indicate differences among the breeding methods, which seem to be related to the different processes for sampling the advanced progenies inherent to each method, given that the trait in question is not subject to natural selection. Variability amongst progenies occurred within the three breeding methods and there was also a significant effect of environment on the progeny for all methods. Progenies developed by bulk-population attained the highest estimates of genetic parameters, had less interaction with the environment, and greater variability. PMID:26125775

  8. Coherence, collective rhythm, and phase difference distribution in populations of stochastic genetic oscillators with cellular communication

    NASA Astrophysics Data System (ADS)

    Yuan, Zhanjiang; Zhang, Jiajun; Zhou, Tianshou

    2008-09-01

    An ensemble of stochastic genetic relaxation oscillators via phase-attractive or repulsive cell-to-cell communication are investigated. In the phase-attractive coupling case, it is found that cellular communication can enhance self-induced stochastic resonance as well as collective rhythms, and that different intensities of noise resulting from the fluctuation of intrinsic chemical reactions or the extrinsic environment can induce stochastic limit cycles with different amplitudes for a large cell density. In contrast, in the phase-repulsive coupling case, the distribution of phase differences among the stochastic oscillators can display such characteristic as unimodality, bimodality or polymodality, depending on both noise intensity and cell number, but the modality of phase difference distribution almost keeps invariant for an arbitrary noise intensity as the cell number is beyond a threshold.

  9. Genetic differences in the ethanol sensitivity of GABA sub A receptors expressed in Xenopus oocytes

    SciTech Connect

    Wafford, K.A.; Burnett, D.M.; Dunwiddie, T.V.; Harris, R.A. )

    1990-07-20

    Animal lines selected for differences in drug sensitivity can be used to help determine the molecular basis of drug action. Long-sleep (LS) and short-sleep (SS) mice differ markedly in their genetic sensitivity to ethanol. To investigate the molecular basis for this difference, mRNA from brains of LS and SS mice was expressed in Xenopus oocytes and the ethanol sensitivity of gamma-aminobutyric acid A (GABA{sub A})- and N-methyl D-aspartate (NMDA) - activated ion channels was tested. Ethanol facilitated GABA responses in oocytes injected with mRNA from LS mice but antagonized responses in oocytes injected with mRNA from SS animals. Ethanol inhibited NMDA responses equally in the two lines. Thus, genes coding for the GABA{sub A} receptor or associated proteins may be critical determinants of individual differences in ethanol sensitivity.

  10. The Neuroanatomy of Genetic Subtype Differences in Prader-Willi Syndrome

    PubMed Central

    Honea, Robyn A.; Holsen, Laura M.; Lepping, Rebecca J.; Perea, Rodrigo; Butler, Merlin G.; Brooks, William M.; Savage, Cary R.

    2012-01-01

    Objective Despite behavioral differences between genetic subtypes of Prader-Willi syndrome, no studies have been published characterizing brain structure in these subgroups. Our goal was to examine differences in the brain structure phenotype of common subtypes of Prader-Willi syndrome (PWS) [chromosome 15q deletions and maternal uniparental disomy 15 (UPD)]. Methods Fifteen individuals with PWS due to a typical deletion ((DEL) Type I; n=5, Type II; n=10), 8 with PWS due to UPD, and 25 age-matched healthy-weight individuals (HWC) participated in structural magnetic resonance imaging (MRI) scans. A custom voxel-based morphometry processing stream was used to examine regional differences in gray and white matter volume between groups, covarying for age, sex, and body mass index (BMI). Results Overall, compared to HWC, PWS individuals had lower gray matter volumes that encompassed the prefrontal, orbitofrontal and temporal cortices, hippocampus and parahippocampal gyrus, and lower white matter volumes in the brain stem, cerebellum, medial temporal and frontal cortex. Compared to UPD, the DEL subtypes had lower gray matter volume primarily in the prefrontal and temporal cortices, and lower white matter in the parietal cortex. The UPD subtype had more extensive lower gray and white matter volumes in the orbitofrontal and limbic cortices compared to HWC. Conclusions These preliminary findings are the first structural neuroimaging findings to support potentially separate neural mechanisms mediating the behavioral differences seen in these genetic subtypes. PMID:22241551

  11. A statistical assessment of differences and equivalences between genetically modified and reference plant varieties

    PubMed Central

    2011-01-01

    Background Safety assessment of genetically modified organisms is currently often performed by comparative evaluation. However, natural variation of plant characteristics between commercial varieties is usually not considered explicitly in the statistical computations underlying the assessment. Results Statistical methods are described for the assessment of the difference between a genetically modified (GM) plant variety and a conventional non-GM counterpart, and for the assessment of the equivalence between the GM variety and a group of reference plant varieties which have a history of safe use. It is proposed to present the results of both difference and equivalence testing for all relevant plant characteristics simultaneously in one or a few graphs, as an aid for further interpretation in safety assessment. A procedure is suggested to derive equivalence limits from the observed results for the reference plant varieties using a specific implementation of the linear mixed model. Three different equivalence tests are defined to classify any result in one of four equivalence classes. The performance of the proposed methods is investigated by a simulation study, and the methods are illustrated on compositional data from a field study on maize grain. Conclusions A clear distinction of practical relevance is shown between difference and equivalence testing. The proposed tests are shown to have appropriate performance characteristics by simulation, and the proposed simultaneous graphical representation of results was found to be helpful for the interpretation of results from a practical field trial data set. PMID:21324199

  12. Evidence from Cameroon reveals differences in the genetic structure and histories of chimpanzee populations.

    PubMed

    Gonder, Mary Katherine; Locatelli, Sabrina; Ghobrial, Lora; Mitchell, Matthew W; Kujawski, Joseph T; Lankester, Felix J; Stewart, Caro-Beth; Tishkoff, Sarah A

    2011-03-22

    The history of the genus Pan is a topic of enduring interest. Chimpanzees (Pan troglodytes) are often divided into subspecies, but the population structure and genetic history of chimpanzees across Africa remain unclear. Some population genetics studies have led to speculation that, until recently, this species constituted a single population with ongoing gene flow across its range, which resulted in a continuous gradient of allele frequencies. Chimpanzees, designated here as P. t. ellioti, occupy the Gulf of Guinea region that spans southern Nigeria and western Cameroon at the center of the distribution of this species. Remarkably, few studies have included individuals from this region, hindering the examination of chimpanzee population structure across Africa. Here, we analyzed microsatellite genotypes of 94 chimpanzees, including 32 designated as P. t. ellioti. We find that chimpanzees fall into three major populations: (i) Upper Guinea in western Africa (P. t. verus); (ii) the Gulf of Guinea region (P. t. ellioti); and (iii) equatorial Africa (P. t. troglodytes and P. t. schweinfurthii). Importantly, the Gulf of Guinea population is significantly different genetically from the others, sharing a last common ancestor with the populations in Upper Guinea ~0.46 million years ago (mya) and equatorial Africa ~0.32 mya. Equatorial chimpanzees are subdivided into up to three populations occupying southern Cameroon, central Africa, and eastern Africa, which may have constituted a single population until ~0.10-0.11 mya. Finally, occasional hybridization may be occurring between the Gulf of Guinea and southern Cameroon populations. PMID:21368170

  13. Genetic variability of Mahanarva sp (Hemiptera: Cercopidae) collected from different sites in Brazil.

    PubMed

    Auad, A M; Domingues, R; Machado, M A; Souza, L S; Carvalho, G S; Paula-Moraes, S V

    2010-01-01

    Spittlebugs are the leading cause of damage to tall grasses. Annual losses are estimated to reach 2.1 billion dollars in sugarcane crops and grazing land throughout the world. Correct identification of these species is difficult due to similarities in color, body size and male genitalia. Molecular markers have been useful in the identification and assessment of genetic diversity of many species. We investigated the genetic diversity of the spittlebug species Mahanarva fimbriolata, M. spectabilis and M. liturata and looked for markers that could aid in their identification. DNA from 34 spittlebug specimens, collected from six different regions of Brazil (Brasília, Campo Grande, Valença, Presidente Prudente, Juiz de Fora, and Porto Alegre), was analyzed with 29 RAPD primers, generating 501 polymorphic markers. High genetic variability was found among individuals M. fimbriolata (0.37), M. spectabilis (0.18) and M. liturata (0.69). Species-specific molecular RAPD markers were identified for each of the three species; these could be used as auxiliary tools for their correct identification. PMID:20533195

  14. Among- and within-patch components of genetic diversity respond at different rates to habitat fragmentation: an empirical demonstration

    PubMed Central

    Keyghobadi, Nusha; Roland, Jens; Matter, Stephen F; Strobeck, Curtis

    2005-01-01

    Habitat fragmentation is a ubiquitous by-product of human activities that can alter the genetic structure of natural populations, with potentially deleterious effects on population persistence and evolutionary potential. When habitat fragmentation results in the subdivision of a population, random genetic drift then leads to the erosion of genetic diversity from within the resulting subpopulations and greater genetic divergence among them. Theoretical and simulation analyses predict that these two main genetic effects of fragmentation, greater differentiation among resulting subpopulations and reduced genetic diversity within them, will proceed at very different rates. Despite important implications for the interpretation of genetic data from fragmented populations, empirical evidence for this phenomenon has been lacking. In this analysis, we carry out an empirical study in populations of an alpine meadow-dwelling butterfly, which have become fragmented by increasing forest cover over five decades. We show that genetic differentiation among subpopulations (GST) is most highly correlated with contemporary forest cover, while genetic diversity within subpopulations (expected heterozygosity) is better correlated with the spatial pattern of forest cover 40 years in the past. Thus, where habitat fragmentation has occurred in recent decades, genetic differentiation among subpopulations can be near equilibrium while contemporary measures of within subpopulation diversity may substantially overestimate the equilibrium values that will eventually be attained. PMID:15799951

  15. Do Different Measures Tap the Same Genetic Influences? A Multi-Method Study of Activity Level in Young Twins

    ERIC Educational Resources Information Center

    Saudino, Kimberly J.

    2009-01-01

    Activity level (AL) is a highly salient feature of child behaviour that has been linked to developmental outcome. Twin studies of parent-rated, observer-rated and mechanically assessed AL in childhood find that AL is genetically influenced. Few studies, however, consider whether different methods of assessing AL have a shared genetic etiology.…

  16. Acceptance of Genetic Testing in a General Population: Age, Education and Gender Differences.

    ERIC Educational Resources Information Center

    Aro, A. R.; Hakonen, A.; Hietala, M.; Lonnqvist, J.; Niemela, P.; Peltonen, L; Aula, P.

    1997-01-01

    Effects of age, education, and gender on acceptance of genetic testing were studied. Finnish participants responded to a questionnaire presenting reasons for and against genetic testing (N=1,967). Intentions to take genetic tests, worries, and experience of genetic test or hereditary disease were also assessed. Results are presented and discussed.…

  17. Mitochondrial genetic differentiation and morphological difference of Miniopterus fuliginosus and Miniopterus magnater in China and Vietnam

    PubMed Central

    Li, Shi; Sun, Keping; Lu, Guanjun; Lin, Aiqing; Jiang, Tinglei; Jin, Longru; Hoyt, Joseph R; Feng, Jiang

    2015-01-01

    Because of its complicated systematics, the bent-winged bat is one of the most frequently studied bat species groups. In China, two morphologically similar bent-winged bat species, Miniopterus fuliginosus and Miniopterus magnater were identified, but their distribution range and genetic differentiation are largely unexplored. In this study, we applied DNA bar codes and two other mitochondrial DNA genes including morphological parameters to determine the phylogeny, genetic differentiation, spatial distribution, and morphological difference of the M. fuliginosus and M. magnater sampled from China and one site in Vietnam. Mitochondrial DNA gene genealogies revealed two monophyletic lineages throughout the Tropic of Cancer. According to DNA bar code divergences, one is M. fuliginosus corresponding to the Chinese mainland and the other is M. magnater corresponding to tropical regions including Hainan and Guangdong provinces of China and Vietnam. Their most recent common ancestor was dated to the early stage of the Quaternary glacial period (ca. 2.26 million years ago [Ma] on the basis of D-loop data, and ca. 1.69–2.37 Ma according to ND2). A population expansion event was inferred for populations of M. fuliginosus at 0.14 Ma. The two species probably arose in separate Pleistocene refugia under different climate zones. They significantly differed in forearm length, maxillary third molar width, and greatest length of the skull. PMID:25859327

  18. Genetic bottlenecks during systemic movement of Cucumber mosaic virus vary in different host plants

    SciTech Connect

    Ali, Akhtar; Roossinck, Marilyn J.

    2010-09-01

    Genetic bottlenecks are stochastic events that narrow variation in a population. We compared bottlenecks during the systemic infection of Cucumber mosaic virus (CMV) in four host plants. We mechanically inoculated an artificial population of twelve CMV mutants to young leaves of tomato, pepper, Nicotiana benthamiana, and squash. The inoculated leaves and primary and secondary systemically infected leaves were sampled at 2, 10, and 15 days post-inoculation. All twelve mutants were detected in all of the inoculated leaves. The number of mutants recovered from the systemically infected leaves of all host species was reduced significantly, indicating bottlenecks in systemic movement. The recovery frequencies of a few of the mutants were significantly different in each host probably due to host-specific selective forces. These results have implications for the differences in virus population variation that is seen in different host plants.

  19. Genetic Subtype Differences in Neural Circuitry of Food Motivation in Prader-Willi Syndrome

    PubMed Central

    Holsen, Laura M.; Zarcone, Jennifer R.; Chambers, Rebecca; Butler, Merlin G.; Bittel, Douglas C.; Brooks, William M.; Thompson, Travis I.; Savage, Cary R.

    2008-01-01

    Background Differences in behavioral phenotypes between the two most common subtypes of Prader-Willi syndrome (PWS) [chromosome 15q deletions and maternal uniparental disomy 15 (UPD)] indicate that distinct neural networks may be affected. Though both subtypes display hyperphagia, the deletion subgroup demonstrates reduced behavioral inhibition around food, whereas those with UPD are generally more able to maintain cognitive control over food intake impulses. Objective To examine the neural basis of phenotypic differences to better understand relationships between genetic subtypes and behavioral outcomes. We predicted greater food motivation circuitry activity in the deletion subtype and greater activity in higher order cognitive regions in the UPD group, especially after eating. Design and Subjects Nine individuals with PWS due to UPD and 9 individuals with PWS due to (type 2) deletion, matched for age, gender, and BMI, underwent fMRI scanning while viewing food images during two food motivation states: one before (pre-meal) and one after (post-meal) eating a standardized 500 kcal meal. Results Both PWS subgroups demonstrated greater activity in response to food pre- and post-meal compared to the healthy-weight group. Compared to UPD, the deletion subtype showed increased food motivation network activation both pre- and post-meal, especially in the medial prefrontal cortex and amygdala. In contrast, the UPD group demonstrated greater activation than the deletion subtype post-meal in the dorsolateral prefrontal cortex and parahippocampal gyrus. Conclusion These preliminary findings are the first functional neuroimaging findings to support divergent neural mechanisms associated with behavioral phenotypes in genetic subtypes of PWS. Results are discussed within the framework of genetic mechanisms such as haploinsufficiency and gene dosage effects and their differential influence on deletion and UPD subtypes, respectively. PMID:19048015

  20. Genetically distinct populations of northern shrimp, Pandalus borealis, in the North Atlantic: adaptation to different temperatures as an isolation factor.

    PubMed

    Jorde, Per Erik; Søvik, Guldborg; Westgaard, Jon-Ivar; Albretsen, Jon; André, Carl; Hvingel, Carsten; Johansen, Torild; Sandvik, Anne Dagrun; Kingsley, Michael; Jørstad, Knut Eirik

    2015-04-01

    The large-scale population genetic structure of northern shrimp, Pandalus borealis, was investigated over the species' range in the North Atlantic, identifying multiple genetically distinct groups. Genetic divergence among sample localities varied among 10 microsatellite loci (range: FST = -0.0002 to 0.0475) with a highly significant average (FST = 0.0149; P < 0.0001). In contrast, little or no genetic differences were observed among temporal replicates from the same localities (FST = 0.0004; P = 0.33). Spatial genetic patterns were compared to geographic distances, patterns of larval drift obtained through oceanographic modelling, and temperature differences, within a multiple linear regression framework. The best-fit model included all three factors and explained approximately 29% of all spatial genetic divergence. However, geographic distance and larval drift alone had only minor effects (2.5-4.7%) on large-scale genetic differentiation patterns, whereas bottom temperature differences explained most (26%). Larval drift was found to promote genetic homogeneity in parts of the study area with strong currents, but appeared ineffective across large temperature gradients. These findings highlight the breakdown of gene flow in a species with a long pelagic larval phase (up to 3 months) and indicate a role for local adaptation to temperature conditions in promoting evolutionary diversification and speciation in the marine environment. PMID:25782085

  1. What Ancestry Can Tell Us About the Genetic Origins of Inter-Ethnic Differences in Asthma Expression.

    PubMed

    Hernandez-Pacheco, Natalia; Flores, Carlos; Oh, Sam S; Burchard, Esteban G; Pino-Yanes, Maria

    2016-07-01

    Differences in asthma prevalence have been described across different populations, suggesting that genetic ancestry can play an important role in this disease. In fact, several studies have demonstrated an association between African ancestry with increased asthma susceptibility and severity, higher immunoglobulin E levels, and lower lung function. In contrast, Native American ancestry has been shown to have a protective role for this disease. Genome-wide association studies have allowed the identification of population-specific genetic variants with varying allele frequency among populations. Additionally, the correlation of genetic ancestry at the chromosomal level with asthma and related traits by means of admixture mapping has revealed regions of the genome where ancestry is correlated with the disease. In this review, we discuss the evidence supporting the association of genetic ancestry with asthma susceptibility and asthma-related traits, and highlight the regions of the genome harboring ancestry-specific genetic risk factors. PMID:27393700

  2. Uniparental Markers in Italy Reveal a Sex-Biased Genetic Structure and Different Historical Strata

    PubMed Central

    Sarno, Stefania; Harmant, Christine; Useli, Antonella; Sanz, Paula; Yang-Yao, Daniele; Manry, Jeremy; Ciani, Graziella; Luiselli, Donata; Quintana-Murci, Lluis; Comas, David; Pettener, Davide

    2013-01-01

    Located in the center of the Mediterranean landscape and with an extensive coastal line, the territory of what is today Italy has played an important role in the history of human settlements and movements of Southern Europe and the Mediterranean Basin. Populated since Paleolithic times, the complexity of human movements during the Neolithic, the Metal Ages and the most recent history of the two last millennia (involving the overlapping of different cultural and demic strata) has shaped the pattern of the modern Italian genetic structure. With the aim of disentangling this pattern and understanding which processes more importantly shaped the distribution of diversity, we have analyzed the uniparentally-inherited markers in ∼900 individuals from an extensive sampling across the Italian peninsula, Sardinia and Sicily. Spatial PCAs and DAPCs revealed a sex-biased pattern indicating different demographic histories for males and females. Besides the genetic outlier position of Sardinians, a North West–South East Y-chromosome structure is found in continental Italy. Such structure is in agreement with recent archeological syntheses indicating two independent and parallel processes of Neolithisation. In addition, date estimates pinpoint the importance of the cultural and demographic events during the late Neolithic and Metal Ages. On the other hand, mitochondrial diversity is distributed more homogeneously in agreement with older population events that might be related to the presence of an Italian Refugium during the last glacial period in Europe. PMID:23734255

  3. Different genetic algorithms and the evolution of specialization: a study with groups of simulated neural robots.

    PubMed

    Ferrauto, Tomassino; Parisi, Domenico; Di Stefano, Gabriele; Baldassarre, Gianluca

    2013-01-01

    Organisms that live in groups, from microbial symbionts to social insects and schooling fish, exhibit a number of highly efficient cooperative behaviors, often based on role taking and specialization. These behaviors are relevant not only for the biologist but also for the engineer interested in decentralized collective robotics. We address these phenomena by carrying out experiments with groups of two simulated robots controlled by neural networks whose connection weights are evolved by using genetic algorithms. These algorithms and controllers are well suited to autonomously find solutions for decentralized collective robotic tasks based on principles of self-organization. The article first presents a taxonomy of role-taking and specialization mechanisms related to evolved neural network controllers. Then it introduces two cooperation tasks, which can be accomplished by either role taking or specialization, and uses these tasks to compare four different genetic algorithms to evaluate their capacity to evolve a suitable behavioral strategy, which depends on the task demands. Interestingly, only one of the four algorithms, which appears to have more biological plausibility, is capable of evolving role taking or specialization when they are needed. The results are relevant for both collective robotics and biology, as they can provide useful hints on the different processes that can lead to the emergence of specialization in robots and organisms. PMID:23514239

  4. Comparison of mineral resources calculation methods for different genetic types of gravel and sand deposits

    NASA Astrophysics Data System (ADS)

    Patašova, Tatjana; Jurgaitis, Algirdas

    2008-01-01

    Calculation of mineral resources and their proper assessment is relevant, since the stock of resources determines the economic independence of the state. The present work discusses gravel and sand deposits of different genetic type (kames, eskers, marginal glaciofluvial ridges, sandurs, glaciofluvial deltas and redrifted glaciofluvial aeolian formations). Their geological structure and formation conditions have been assessed; quality characteristics of mineral resources have been analysed; calculation of resources has been performed by applying old methods used in Lithuania up to now, such as those of geological blocks, profiles and isolines, as well as the up-to-date GRID method created on the basis of the triangle method in GIS environment. Comparison of resources assessed by different methods has revealed their advantages and disadvantages.

  5. Genetically determined differences in ethanol sensitivity influenced by body temperature during intoxication

    SciTech Connect

    Alkana, R.L.; Finn, D.A.; Bejanian, M.; Crabbe, J.C.

    1988-01-01

    The present study investigated the importance of body temperature during intoxication in mediating differences between five inbred strains of mice (C57BL/6J; BALB/cJ; DBA/2J; A/HeJ; 129/J) in their acute sensitivity to the hypnotic effects of ethanol. Mice exposed to 22/degrees/C after ethanol injection became hypothermic and exhibited statistically significant differences between strains in rectal temperatures at the return of the righting reflex (RORR), duration of loss of the righting reflex (LORR), and blood and brain ethanol concentrations at RORR. Exposure to 34/degrees/C after injection offset ethanol-hypothermia and markedly reduced strain-related differences in rectal temperatures and blood and brain ethanol concentrations at RORR. Brain ethanol concentrations at RORR were significantly lower in C57, BALB, DBA and A/He mice exposed to 34/degrees/C compared to mice exposed to 22/degrees/C during intoxication suggesting that offsetting hypothermia increased ethanol sensitivity in these strains. Taken with previous in vitro studies, these results suggest that genetically determined differences in acute sensitivity to the behavioral effects of ethanol reflect differences in body temperature during intoxication as well as differences in sensitivity to the initial actions of ethanol at the cellular level.

  6. Evidence that glutathione S-transferases B1B1 and B2B2 are the products of separate genes and that their expression in human liver is subject to inter-individual variation. Molecular relationships between the B1 and B2 subunits and other Alpha class glutathione S-transferases.

    PubMed Central

    Hayes, J D; Kerr, L A; Cronshaw, A D

    1989-01-01

    The Alpha class glutathione S-transferases (GSTs) in human liver are composed of polypeptides of Mr 25,900. These enzymes are dimeric, and two immunochemically distinct subunits, B1 and B2, have been described that combine to form GSTs B1B1, B1B2 and B2B2 [Stockman, Beckett & Hayes (1985) Biochem. J. 227, 457-465]. Gradient affinity elution from GSH-Sepharose has been used to resolve the three Alpha class GSTs, and this method has been applied to demonstrate marked inter-individual differences in the hepatic content of GSTs B1B1, B1B2 and B2B2. The B1 and B2 subunits can be resolved by reverse-phase h.p.l.c., and their elution positions suggest that they are equivalent to the alpha chi and alpha y h.p.l.c. peaks described by Ketterer and his colleagues [Ostlund Farrants, Meyer, Coles, Southan, Aitken, Johnson & Ketterer (1987) Biochem. J. 245, 423-428]. The B1 and B2 subunits have now been cleaved with CNBr and the fragments subjected to automated amino acid sequence analysis. The sequence data show that B1 and B2 subunits do not arise from post-translational modification, as had been previously believed for the hepatic Alpha class GSTs, but are instead the products of separate genes; B1 and B2 subunits were found to contain different amino acid residues at positions 88, 110, 111, 112, 116, 124 and 127. The relationship between the B1 and B2 subunits and the cloned GTH1 and GTH2 cDNA sequences [Rhoads, Zarlengo & Tu (1987) Biochem. Biophys. Res. Commun. 145, 474-481] is discussed. PMID:2604726

  7. A novel genetic map of wheat: utility for mapping QTL for yield under different nitrogen treatments

    PubMed Central

    2014-01-01

    Background Common wheat (Triticum aestivum L.) is one of the most important food crops worldwide. Wheat varieties that maintain yield (YD) under moderate or even intense nitrogen (N) deficiency can adapt to low input management systems. A detailed genetic map is necessary for both wheat molecular breeding and genomics research. In this study, an F6:7 recombinant inbred line population comprising 188 lines was used to construct a novel genetic map and subsequently to detect quantitative trait loci (QTL) for YD and response to N stress. Results A genetic map consisting of 591 loci distributed across 21 wheat chromosomes was constructed. The map spanned 3930.7 cM, with one marker per 6.7 cM on average. Genomic simple sequence repeat (g-SSR), expressed sequence tag-derived microsatellite (e-SSR), diversity arrays technology (DArT), sequence-tagged sites (STS), sequence-related amplified polymorphism (SRAP), and inter-simple sequence repeat (ISSR) molecular markers were included in the map. The linear relationships between loci found in the present map and in previously compiled physical maps were presented, which were generally in accordance. Information on the genetic and physical positions and allele sizes (when possible) of 17 DArT, 50 e-SSR, 44 SRAP, five ISSR, and two morphological markers is reported here for the first time. Seven segregation distortion regions (SDR) were identified on chromosomes 1B, 3BL, 4AL, 6AS, 6AL, 6BL, and 7B. A total of 22 and 12 QTLs for YD and yield difference between the value (YDDV) under HN and the value under LN were identified, respectively. Of these, QYd-4B-2 and QYddv-4B, two major stable QTL, shared support interval with alleles from KN9204 increasing YD in LN and decreasing YDDV. We probe into the use of these QTLs in wheat breeding programs. Moreover, factors affecting the SDR and total map length are discussed in depth. Conclusions This novel map may facilitate the use of novel markers in wheat molecular breeding programs

  8. Effects of colonization processes on genetic diversity: differences between annual plants and tree species.

    PubMed Central

    Austerlitz, F; Mariette, S; Machon, N; Gouyon, P H; Godelle, B

    2000-01-01

    Tree species are striking for their high within-population diversity and low among-population differentiation for nuclear genes. In contrast, annual plants show much more differentiation for nuclear genes but much less diversity than trees. The usual explanation for this difference is that pollen flow, and therefore gene flow, is much higher for trees. This explanation is problematic because it relies on equilibrium hypotheses. Because trees have very recently recolonized temperate areas, they have experienced many foundation events, which usually reduce within-population diversity and increase differentiation. Only extremely high levels of gene flow could counterbalance these successive founder effects. We develop a model to study the impact of life cycle of forest trees, in particular of the length of their juvenile phase, on genetic diversity and differentiation during the glacial period and the following colonization period. We show that both a reasonably high level of pollen flow and the life-cycle characteristics of trees are needed to explain the observed structure of genetic diversity. We also show that gene flow and life cycle both have an impact on maternally inherited cytoplasmic genes, which are characterized both in trees and annual species by much less diversity and much more differentiation than nuclear genes. PMID:10757772

  9. Can genetic differences explain vocal dialect variation in sperm whales, Physeter macrocephalus?

    PubMed

    Rendell, Luke; Mesnick, Sarah L; Dalebout, Merel L; Burtenshaw, Jessica; Whitehead, Hal

    2012-03-01

    Sperm whale social groups can be assigned to vocal clans based on their production of codas, short stereotyped patterns of clicks. It is currently unclear whether genetic variation could account for these behavioural differences. We studied mitochondrial DNA (mtDNA) variation among sympatric vocal clans in the Pacific Ocean, using sequences extracted from sloughed skin samples. We sampled 194 individuals from 30 social groups belonging to one of three vocal clans. As in previous studies of sperm whales, mtDNA control region diversity was low (π = 0.003), with just 14 haplotypes present in our sample. Both hierarchical AMOVAs and partial Mantel tests showed that vocal clan was a more important factor in matrilineal population genetic structure than geography, even though our sampling spanned thousands of kilometres. The variance component attributed to vocal dialects (7.7%) was an order of magnitude higher than those previously reported in birds, while the variance component attributed to geographic area was negligible. Despite this, the two most common haplotypes were present in significant quantities in each clan, meaning that variation in the control region cannot account for behavioural variation between clans, and instead parallels the situation in humans where parent-offspring transmission of language variation has resulted in correlations with neutral genes. Our results also raise questions for the management of sperm whale populations, which has traditionally been based on dividing populations into geographic 'stocks', suggesting that culturally-defined vocal clans may be more appropriate management units. PMID:22015469

  10. Genetic diversity among different physiological traits of Sorghum bicolor cultivars of subtropical origin.

    PubMed

    Bafeel, S O

    2015-01-01

    The genetic diversity of Saudi locally growing sorghum (Sorghum bicolor) cultivars has not been thoroughly characterized. To understand the genomic patterns of diversification in Saudi sorghum cultivars (N = 7), random amplified polymorphic DNA (RAPD) was used as a rapid, inexpensive method for providing information regarding genomic variability below the species level. Six commercially available primers were initially used to select a single primer based on availability, universality, and its use with standard polymerase chain reaction (PCR) conditions. PCR-amplified molecular markers were reproducibly detected in Saudi cultivars. The single primer 2 produced clear bands and revealed variability among the cultivars. Seven tested cultivars were categorized into 2 major groups, indicating 2 genomogroups for the Saudi-cultivars. Five cultivars (S2, S3, S4, S5, and S6) showed identical banding patterns and were grouped in the same clade, although their panicles varied in size, shape, and color. Two cultivars (S1 and S7) showed different banding patterns. In this study, a single primer (P2) was used to demonstrate the effectiveness of genotype detection among sorghum cultivars. This is the first report describing genetic variation among S. bicolor cultivars in Saudi Arabia. The commercial primer (P2) and PCR reaction mixture used in this study are readily available and can be used in sorghum improvement programs. PMID:26345933