Genetic determinants of facial clefting

DEFF Research Database (Denmark)

Jugessur, Astanand; Shi, Min; Gjessing, Håkon Kristian

2009-01-01

BACKGROUND: Facial clefts are common birth defects with a strong genetic component. To identify fetal genetic risk factors for clefting, 1536 SNPs in 357 candidate genes were genotyped in two population-based samples from Scandinavia (Norway: 562 case-parent and 592 control-parent triads; Denmark...

Diabetes-specific genetic effects on obesity traits in American Indian populations: the Strong Heart Family Study

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Howard Barbara V

2008-10-01

Full Text Available Abstract Background Body fat mass distribution and deposition are determined by multiple environmental and genetic factors. Obesity is associated with insulin resistance, hyperinsulinemia, and type 2 diabetes. We previously identified evidence for genotype-by-diabetes interaction on obesity traits in Strong Heart Family Study (SHFS participants. To localize these genetic effects, we conducted genome-wide linkage scans of obesity traits in individuals with and without type 2 diabetes, and in the combined sample while modeling interaction with diabetes using maximum likelihood methods (SOLAR 2.1.4. Methods SHFS recruited American Indians from Arizona, North and South Dakota, and Oklahoma. Anthropometric measures and diabetes status were obtained during a clinic visit. Marker allele frequencies were derived using maximum likelihood methods estimated from all individuals and multipoint identity by descent sharing was estimated using Loki. We used variance component linkage analysis to localize quantitative trait loci (QTLs influencing obesity traits. We tested for evidence of additive and QTL-specific genotype-by-diabetes interactions using the regions identified in the diabetes-stratified analyses. Results Among 245 diabetic and 704 non-diabetic American Indian individuals, we detected significant additive gene-by-diabetes interaction for weight and BMI (P P Conclusion These results suggest distinct genetic effects on body mass in individuals with diabetes compared to those without diabetes, and a possible role for one or more genes on chromosome 1 in the pathogenesis of obesity.

Common Genetic Components of Obesity Traits and Serum Leptin

DEFF Research Database (Denmark)

Hasselbalch, Ann L; Benyamin, Beben; Visscher, Peter M

2008-01-01

To estimate common and distinct genetic influences on a panel of obesity-related traits and serum leptin level in adults. In a cross-sectional study of 625 Danish, adult, healthy, monozygotic, and same-sex dizygotic twin pairs of both genders, we carried out detailed anthropometry (height, weight...... components, which suggests that it is important to distinguish between the different phenotypes in the search for genes involved in the development of obesity.Obesity (2008) doi:10.1038/oby.2008.440........ For leptin vs. the various measures of overall and local fatness the correlations ranged from 0.54 to 0.74 in men and from 0.48 to 0.75 in women. All correlations were significantly different genetic...

Focusing light through strongly scattering media using genetic algorithm with SBR discriminant

Science.gov (United States)

Zhang, Bin; Zhang, Zhenfeng; Feng, Qi; Liu, Zhipeng; Lin, Chengyou; Ding, Yingchun

2018-02-01

In this paper, we have experimentally demonstrated light focusing through strongly scattering media by performing binary amplitude optimization with a genetic algorithm. In the experiments, we control 160 000 mirrors of digital micromirror device to modulate and optimize the light transmission paths in the strongly scattering media. We replace the universal target-position-intensity (TPI) discriminant with signal-to-background ratio (SBR) discriminant in genetic algorithm. With 400 incident segments, a relative enhancement value of 17.5% with a ground glass diffuser is achieved, which is higher than the theoretical value of 1/(2π )≈ 15.9 % for binary amplitude optimization. According to our repetitive experiments, we conclude that, with the same segment number, the enhancement for the SBR discriminant is always higher than that for the TPI discriminant, which results from the background-weakening effect of SBR discriminant. In addition, with the SBR discriminant, the diameters of the focus can be changed ranging from 7 to 70 μm at arbitrary positions. Besides, multiple foci with high enhancement are obtained. Our work provides a meaningful reference for the study of binary amplitude optimization in the wavefront shaping field.

Genetic and environmental contributions to cardiovascular disease risk in American Indians: the strong heart family study.

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North, Kari E; Howard, Barbara V; Welty, Thomas K; Best, Lyle G; Lee, Elisa T; Yeh, J L; Fabsitz, Richard R; Roman, Mary J; MacCluer, Jean W

2003-02-15

The aims of the Strong Heart Family Study are to clarify the genetic determinants of cardiovascular disease (CVD) risk in American Indians and to map and identify genes for CVD susceptibility. The authors describe the design of the Strong Heart Family Study (conducted between 1998 and 1999) and evaluate the heritabilities of CVD risk factors in American Indians from this study. In the first phase of the study, approximately 950 individuals, aged 18 years or more, in 32 extended families, were examined. The examination consisted of a personal interview, physical examination, laboratory tests, and an ultrasound examination of the carotid arteries. The phenotypes measured during the physical examination included anthropometry, lipoproteins, blood pressure, glycemic status, and clotting factors. Heritabilities for CVD risk factor phenotypes were estimated using a variance component approach and the program SOLAR. After accounting for the effects of covariates, the authors detected significant heritabilities for many CVD risk factor phenotypes (e.g., high density lipoprotein cholesterol (heritability = 0.50) and diastolic blood pressure (heritability = 0.34)). These results suggest that heredity explains a substantial proportion of the variability of CVD risk factors and that these heritabilities are large enough to warrant a search for major risk factor genes.

Components of genetic variability of ear length of silage maize

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Sečanski Mile

2006-01-01

Full Text Available The objective of this study was to evaluate following parameters of the ear length of silage maize: variability of inbred lines and their diallel hybrids, superior-parent heterosis and genetic components of variability and habitability on the basis of a diallel set. The analysis of genetic variance shows that the additive component (D was lower than the dominant (H1 and H2 genetic variances, while the frequency of dominant genes (u for this trait was greater than the frequency of recessive genes (v Furthermore, this is also confirmed by the dominant to recessive genes ratio in parental inbreeds for the ear length (Kd/Kr> 1, which is greater than unity during both investigation years. The calculated value of the average degree of dominance √H1/D is greater than unity, pointing out to superdominance in inheritance of this trait in both years of investigation, which is also confirmed by the results of Vr/Wr regression analysis of inheritance of the ear length. As a presence of the non-allelic interaction was established it is necessary to study effects of epitasis as it can have a greater significance in certain hybrids. A greater value of dominant than additive variance resulted in high broad-sense habitability for ear length in both investigation years.

Implications of recurrent disturbance for genetic diversity.

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Davies, Ian D; Cary, Geoffrey J; Landguth, Erin L; Lindenmayer, David B; Banks, Sam C

2016-02-01

Exploring interactions between ecological disturbance, species' abundances and community composition provides critical insights for ecological dynamics. While disturbance is also potentially an important driver of landscape genetic patterns, the mechanisms by which these patterns may arise by selective and neutral processes are not well-understood. We used simulation to evaluate the relative importance of disturbance regime components, and their interaction with demographic and dispersal processes, on the distribution of genetic diversity across landscapes. We investigated genetic impacts of variation in key components of disturbance regimes and spatial patterns that are likely to respond to climate change and land management, including disturbance size, frequency, and severity. The influence of disturbance was mediated by dispersal distance and, to a limited extent, by birth rate. Nevertheless, all three disturbance regime components strongly influenced spatial and temporal patterns of genetic diversity within subpopulations, and were associated with changes in genetic structure. Furthermore, disturbance-induced changes in temporal population dynamics and the spatial distribution of populations across the landscape resulted in disrupted isolation by distance patterns among populations. Our results show that forecast changes in disturbance regimes have the potential to cause major changes to the distribution of genetic diversity within and among populations. We highlight likely scenarios under which future changes to disturbance size, severity, or frequency will have the strongest impacts on population genetic patterns. In addition, our results have implications for the inference of biological processes from genetic data, because the effects of dispersal on genetic patterns were strongly mediated by disturbance regimes.

A major genetic component of BSE susceptibility

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Juling, Katrin; Schwarzenbacher, Hermann; Williams, John L; Fries, Ruedi

2006-01-01

Background Coding variants of the prion protein gene (PRNP) have been shown to be major determinants for the susceptibility to transmitted prion diseases in humans, mice and sheep. However, to date, the effects of polymorphisms in the coding and regulatory regions of bovine PRNP on bovine spongiform encephalopathy (BSE) susceptibility have been considered marginal or non-existent. Here we analysed two insertion/deletion (indel) polymorphisms in the regulatory region of bovine PRNP in BSE affected animals and controls of four independent cattle populations from UK and Germany. Results In the present report, we show that two previously reported 23- and 12-bp insertion/deletion (indel) polymorphisms in the regulatory region of bovine PRNP are strongly associated with BSE incidence in cattle. Genotyping of BSE-affected and control animals of UK Holstein, German Holstein, German Brown and German Fleckvieh breeds revealed a significant overrepresentation of the deletion alleles at both polymorphic sites in diseased animals (P = 2.01 × 10-3 and P = 8.66 × 10-5, respectively). The main effect on susceptibility is associated with the 12-bp indel polymorphism. Compared with non-carriers, heterozygous and homozygous carriers of the 12-bp deletion allele possess relatively higher risks of having BSE, ranging from 1.32 to 4.01 and 1.74 to 3.65 in the different breeds. These values correspond to population attributable risks ranging from 35% to 53%. Conclusion Our results demonstrate a substantial genetic PRNP associated component for BSE susceptibility in cattle. Although the BSE risk conferred by the deletion allele of the 12-bp indel in the regulatory region of PRNP is substantial, the main risk factor for BSE in cattle is environmental, i.e. exposure to feedstuffs contaminated with the infectious agent. PMID:17014722

A major genetic component of BSE susceptibility

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Williams John L

2006-10-01

Full Text Available Abstract Background Coding variants of the prion protein gene (PRNP have been shown to be major determinants for the susceptibility to transmitted prion diseases in humans, mice and sheep. However, to date, the effects of polymorphisms in the coding and regulatory regions of bovine PRNP on bovine spongiform encephalopathy (BSE susceptibility have been considered marginal or non-existent. Here we analysed two insertion/deletion (indel polymorphisms in the regulatory region of bovine PRNP in BSE affected animals and controls of four independent cattle populations from UK and Germany. Results In the present report, we show that two previously reported 23- and 12-bp insertion/deletion (indel polymorphisms in the regulatory region of bovine PRNP are strongly associated with BSE incidence in cattle. Genotyping of BSE-affected and control animals of UK Holstein, German Holstein, German Brown and German Fleckvieh breeds revealed a significant overrepresentation of the deletion alleles at both polymorphic sites in diseased animals (P = 2.01 × 10-3 and P = 8.66 × 10-5, respectively. The main effect on susceptibility is associated with the 12-bp indel polymorphism. Compared with non-carriers, heterozygous and homozygous carriers of the 12-bp deletion allele possess relatively higher risks of having BSE, ranging from 1.32 to 4.01 and 1.74 to 3.65 in the different breeds. These values correspond to population attributable risks ranging from 35% to 53%. Conclusion Our results demonstrate a substantial genetic PRNP associated component for BSE susceptibility in cattle. Although the BSE risk conferred by the deletion allele of the 12-bp indel in the regulatory region of PRNP is substantial, the main risk factor for BSE in cattle is environmental, i.e. exposure to feedstuffs contaminated with the infectious agent.

Genetic covariance components within and among linear type traits differ among contrasting beef cattle breeds.

Science.gov (United States)

Doyle, Jennifer L; Berry, Donagh P; Walsh, Siobhan W; Veerkamp, Roel F; Evans, Ross D; Carthy, Tara R

2018-05-04

Linear type traits describing the skeletal, muscular, and functional characteristics of an animal are routinely scored on live animals in both the dairy and beef cattle industries. Previous studies have demonstrated that genetic parameters for certain performance traits may differ between breeds; no study, however, has attempted to determine if differences exist in genetic parameters of linear type traits among breeds or sexes. Therefore, the objective of the present study was to determine if genetic covariance components for linear type traits differed among five contrasting cattle breeds, and to also investigate if these components differed by sex. A total of 18 linear type traits scored on 3,356 Angus (AA), 31,049 Charolais (CH), 3,004 Hereford (HE), 35,159 Limousin (LM), and 8,632 Simmental (SI) were used in the analysis. Data were analyzed using animal linear mixed models which included the fixed effects of sex of the animal (except in the investigation into the presence of sexual dimorphism), age at scoring, parity of the dam, and contemporary group of herd-date of scoring. Differences (P covariance parameters estimated from the CH breed with a linear function of breeding values computed conditional on covariance parameters estimated from the other breeds was estimated. Replacing the genetic covariance components estimated in the CH breed with those of the LM had least effect but the impact was considerable when the genetic covariance components of the AA were used. Genetic correlations between the same linear type traits in the two sexes were all close to unity (≥0.90) suggesting little advantage in considering these as separate traits for males and females. Results for the present study indicate the potential increase in accuracy of estimated breeding value prediction from considering, at least, the British breed traits separate to continental breed traits.

Temporal genetic stability in natural populations of the waterflea Daphnia magna in response to strong selection pressure.

Science.gov (United States)

Orsini, Luisa; Marshall, Hollie; Cuenca Cambronero, Maria; Chaturvedi, Anurag; Thomas, Kelley W; Pfrender, Michael E; Spanier, Katina I; De Meester, Luc

2016-12-01

Studies monitoring changes in genetic diversity and composition through time allow a unique understanding of evolutionary dynamics and persistence of natural populations. However, such studies are often limited to species with short generation times that can be propagated in the laboratory or few exceptional cases in the wild. Species that produce dormant stages provide powerful models for the reconstruction of evolutionary dynamics in the natural environment. A remaining open question is to what extent dormant egg banks are an unbiased representation of populations and hence of the species' evolutionary potential, especially in the presence of strong environmental selection. We address this key question using the water flea Daphnia magna, which produces dormant stages that accumulate in biological archives over time. We assess temporal genetic stability in three biological archives, previously used in resurrection ecology studies showing adaptive evolutionary responses to rapid environmental change. We show that neutral genetic diversity does not decline with the age of the population and it is maintained in the presence of strong selection. In addition, by comparing temporal genetic stability in hatched and unhatched populations from the same biological archive, we show that dormant egg banks can be consulted to obtain a reliable measure of genetic diversity over time, at least in the multidecadal time frame studied here. The stability of neutral genetic diversity through time is likely mediated by the buffering effect of the resting egg bank. © 2016 John Wiley & Sons Ltd.

Genetic and other factors determining mannose-binding lectin levels in American Indians: the Strong Heart Study

DEFF Research Database (Denmark)

Best, Lyle G; Ferrell, Robert E; Decroo, Susan

2009-01-01

control of MBL2 expression is complex and genetic background effects in specific populations are largely unknown. METHODS: The Strong Heart Study is a longitudinal, cohort study of cardiovascular disease among American Indians. A subset of individuals genotyped for the above mentioned case-control study...... in Caucasian and other populations, result in markedly reduced expression of functional protein. Prospective epidemiologic studies, including a nested, case-control study from the present population, have demonstrated the ability of MBL2 genotypes to predict complications of atherosclerosis,. The genetic...

Self-Assembling Multi-Component Nanofibers for Strong Bioinspired Underwater Adhesives

Science.gov (United States)

Zhong, Chao; Gurry, Thomas; Cheng, Allen A; Downey, Jordan; Deng, Zhengtao; Stultz, Collin M.; Lu, Timothy K

2014-01-01

Many natural underwater adhesives harness hierarchically assembled amyloid nanostructures to achieve strong and robust interfacial adhesion under dynamic and turbulent environments. Despite recent advances, our understanding of the molecular design, self-assembly, and structure-function relationship of those natural amyloid fibers remains limited. Thus, designing biomimetic amyloid-based adhesives remains challenging. Here, we report strong and multi-functional underwater adhesives obtained from fusing mussel foot proteins (Mfps) of Mytilus galloprovincialis with CsgA proteins, the major subunit of Escherichia coli amyloid curli fibers. These hybrid molecular materials hierarchically self-assemble into higher-order structures, in which, according to molecular dynamics simulations, disordered adhesive Mfp domains are exposed on the exterior of amyloid cores formed by CsgA. Our fibers have an underwater adhesion energy approaching 20.9 mJ/m2, which is 1.5 times greater than the maximum of bio-inspired and bio-derived protein-based underwater adhesives reported thus far. Moreover, they outperform Mfps or curli fibers taken on their own at all pHs and exhibit better tolerance to auto-oxidation than Mfps at pH ≥7.0. This work establishes a platform for engineering multi-component self-assembling materials inspired by nature. PMID:25240674

Variation in the peacock's train shows a genetic component.

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Petrie, Marion; Cotgreave, Peter; Pike, Thomas W

2009-01-01

Female peafowl (Pavo cristatus) show a strong mating preference for males with elaborate trains. This, however, poses something of a paradox because intense directional selection should erode genetic variation in the males' trains, so that females will no longer benefit by discriminating among males on the basis of these traits. This situation is known as the 'lek paradox', and leads to the theoretical expectation of low heritability in the peacock's train. We used two independent breeding experiments, involving a total of 42 sires and 86 of their male offspring, to estimate the narrow sense heritabilities of male ornaments and other morphometric traits. Contrary to expectation, we found significant levels of heritability in a trait known to be used by females during mate choice (train length), while no significant heritabilities were evident for other, non-fitness related morphological traits (tarsus length, body weight or spur length). This study adds to the building body of evidence that high levels of additive genetic variance can exist in secondary sexual traits under directional selection, but further emphasizes the main problem of what maintains this variation.

Strong population genetic structuring in an annual fish, Nothobranchius furzeri, suggests multiple savannah refugia in southern Mozambique.

Science.gov (United States)

Bartáková, Veronika; Reichard, Martin; Janko, Karel; Polačik, Matej; Blažek, Radim; Reichwald, Kathrin; Cellerino, Alessandro; Bryja, Josef

2013-09-12

Intraspecific genetic variation of African fauna has been significantly affected by pronounced climatic fluctuations in Plio-Pleistocene, but, with the exception of large mammals, very limited empirical data on diversity of natural populations are available for savanna-dwelling animals. Nothobranchius furzeri is an annual fish from south-eastern Africa, inhabiting discrete temporary savannah pools outside main river alluvia. Their dispersal is limited and population processes affecting its genetic structure are likely a combination of those affecting terrestrial and aquatic taxa. N. furzeri is a model taxon in ageing research and several populations of known geographical origin are used in laboratory studies. Here, we analysed the genetic structure, diversity, historical demography and temporal patterns of divergence in natural populations of N. furzeri across its entire distribution range. Genetic structure and historical demography of N. furzeri were analysed using a combination of mitochondrial (partial cytochrome b sequences, 687 bp) and nuclear (13 microsatellites) markers in 693 fish from 36 populations. Genetic markers consistently demonstrated strong population structuring and suggested two main genetic groups associated with river basins. The split was dated to the Pliocene (>2 Mya). The northern group inhabits savannah pools across the basin of the intermittent river Chefu in south-western Mozambique and eastern Zimbabwe. The southern group (from southernmost Mozambique) is subdivided, with the River Limpopo forming a barrier (maximum divergence time 1 Mya). A strong habitat fragmentation (isolated temporary pools) is reflected in significant genetic structuring even between adjacent pools, with a major influence of genetic drift and significant isolation-by-distance. Analysis of historical demography revealed that the expansion of both groups is ongoing, supported by frequent founder effects in marginal parts of the range and evidence of secondary

Strong spatial genetic structure in five tropical Piper species: should the Baker–Fedorov hypothesis be revived for tropical shrubs?

Science.gov (United States)

Lasso, E; Dalling, J W; Bermingham, E

2011-01-01

Fifty years ago, Baker and Fedorov proposed that the high species diversity of tropical forests could arise from the combined effects of inbreeding and genetic drift leading to population differentiation and eventually to sympatric speciation. Decades of research, however have failed to support the Baker–Fedorov hypothesis (BFH), and it has now been discarded in favor of a paradigm where most trees are self-incompatible or strongly outcrossing, and where long-distance pollen dispersal prevents population drift. Here, we propose that several hyper-diverse genera of tropical herbs and shrubs, including Piper (>1,000 species), may provide an exception. Species in this genus often have aggregated, high-density populations with self-compatible breeding systems; characteristics which the BFH would predict lead to high local genetic differentiation. We test this prediction for five Piper species on Barro Colorado Island, Panama, using Amplified Fragment Length Polymorphism (AFLP) markers. All species showed strong genetic structure at both fine- and large-spatial scales. Over short distances (200–750 m) populations showed significant genetic differentiation (Fst 0.11–0.46, P < 0.05), with values of spatial genetic structure that exceed those reported for other tropical tree species (Sp = 0.03–0.136). This genetic structure probably results from the combined effects of limited seed and pollen dispersal, clonal spread, and selfing. These processes are likely to have facilitated the diversification of populations in response to local natural selection or genetic drift and may explain the remarkable diversity of this rich genus. PMID:22393518

Pathogenesis of Preeclampsia: The Genetic Component

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Francisco J. Valenzuela

2012-01-01

Full Text Available Preeclampsia (PE is one of the main causes of maternal and fetal morbidity and mortality in the world, causing nearly 40% of births delivered before 35 weeks of gestation. PE begins with inadequate trophoblast invasion early in pregnancy, which produces an increase in oxidative stress contributing to the development of systemic endothelial dysfunction in the later phases of the disease, leading to the characteristic clinical manifestation of PE. Numerous methods have been used to predict the onset of PE with different degrees of efficiency. These methods have used fetal/placental and maternal markers in different stages of pregnancy. From an epidemiological point of view, many studies have shown that PE is a disease with a strong familiar predisposition, which also varies according to geographical, socioeconomic, and racial features, and this information can be used in the prediction process. Large amounts of research have shown a genetic association with a multifactorial polygenic inheritance in the development of this disease. Many biological candidate genes and polymorphisms have been examined in their relation with PE. We will discuss the most important of them, grouped by the different pathogenic mechanisms involved in PE.

Migraine genetics : from monogenic to complex forms

NARCIS (Netherlands)

Vanmolkot, Kaate Raymond Josepha

2008-01-01

Migraine has a strong genetic component, but the identification of these factors has proven difficult mainly because of the complex interaction of multiple loci and environmental factors. Unraveling its molecular basis and deciphering pathways leading to migraine attacks will help identifying novel

Genetics of ischemic stroke: future clinical applications.

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Wang, Michael M

2006-11-01

Ischemic stroke has long been thought to have a genetic component that is independent of conventional vascular risk factors. It has been estimated that over one half of stroke risk is determined by inherited genes. However, until recently, strong evidence of genetic influence on ischemic stroke has been subject to criticism because the risk factors for stroke are also inherited and because previous studies suffered from limitations imposed by this highly heterogeneous neurological disorder. Recent advances in molecular genetics have led to the identification of specific genetic loci that impart susceptibility to ischemic stroke. We review the studies of these genes and discuss the future potential applications of genetic markers on the management of ischemic stroke patients.

Strong evidence for a genetic contribution to late-onset Alzheimer's disease mortality: a population-based study.

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John S K Kauwe

Full Text Available Alzheimer's disease (AD is an international health concern that has a devastating effect on patients and families. While several genetic risk factors for AD have been identified much of the genetic variance in AD remains unexplained. There are limited published assessments of the familiality of Alzheimer's disease. Here we present the largest genealogy-based analysis of AD to date.We assessed the familiality of AD in The Utah Population Database (UPDB, a population-based resource linking electronic health data repositories for the state with the computerized genealogy of the Utah settlers and their descendants. We searched UPDB for significant familial clustering of AD to evaluate the genetic contribution to disease. We compared the Genealogical Index of Familiality (GIF between AD individuals and randomly selected controls and estimated the Relative Risk (RR for a range of family relationships. Finally, we identified pedigrees with a significant excess of AD deaths.The GIF analysis showed that pairs of individuals dying from AD were significantly more related than expected. This excess of relatedness was observed for both close and distant relationships. RRs for death from AD among relatives of individuals dying from AD were significantly increased for both close and more distant relatives. Multiple pedigrees had a significant excess of AD deaths.These data strongly support a genetic contribution to the observed clustering of individuals dying from AD. This report is the first large population-based assessment of the familiality of AD mortality and provides the only reported estimates of relative risk of AD mortality in extended relatives to date. The high-risk pedigrees identified show a true excess of AD mortality (not just multiple cases and are greater in depth and width than published AD pedigrees. The presence of these high-risk pedigrees strongly supports the possibility of rare predisposition variants not yet identified.

Genetic and Quantitative Trait Locus Analysis of Cell Wall Components and Forage Digestibility in the Zheng58 × HD568 Maize RIL Population at Anthesis Stage.

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Li, Kun; Wang, Hongwu; Hu, Xiaojiao; Ma, Feiqian; Wu, Yujin; Wang, Qi; Liu, Zhifang; Huang, Changling

2017-01-01

The plant cell wall plays vital roles in various aspects of the plant life cycle. It provides a basic structure for cells and gives mechanical rigidity to the whole plant. Some complex cell wall components are involved in signal transduction during pathogenic infection and pest infestations. Moreover, the lignification level of cell walls strongly influences the digestibility of forage plants. To determine the genetic bases of cell wall components and digestibility, quantitative trait locus (QTL) analyses for six related traits were performed using a recombinant inbred line (RIL) population from a cross between Zheng58 and HD568. Eight QTL for in vitro neutral detergent fiber (NDF) digestibility were observed, out of which only two increasing alleles came from HD568. Three QTL out of ten with alleles increasing in vitro dry matter digestibility also originated from HD568. Five-ten QTL were detected for lignin, cellulose content, acid detergent fiber, and NDF content. Among these results, 29.8% (14/47) of QTL explained >10% of the phenotypic variation in the RIL population, whereas 70.2% (33/47) explained ≤10%. These results revealed that in maize stalks, a few large-effect QTL and a number of minor-effect QTL contributed to most of the genetic components involved in cell wall biosynthesis and digestibility.

Future possibilities in migraine genetics

DEFF Research Database (Denmark)

Rudkjøbing, Laura Aviaja; Esserlind, Ann-Louise; Olesen, Jes

2012-01-01

Migraine with and without aura (MA and MO, respectively) have a strong genetic basis. Different approaches using linkage-, candidate gene- and genome-wide association studies have been explored, yielding limited results. This may indicate that the genetic component in migraine is due to rare...... variants; capturing these will require more detailed sequencing in order to be discovered. Next-generation sequencing (NGS) techniques such as whole exome and whole genome sequencing have been successful in finding genes in especially monogenic disorders. As the molecular genetics research progresses......, the technology will follow, rendering these approaches more applicable in the search for causative migraine genes in MO and MA. To date, no studies using NGS in migraine genetics have been published. In order to gain insight into the future possibilities of migraine genetics, we have looked at NGS studies...

Roles of Vascular and Metabolic Components in Cognitive Dysfunction of Alzheimer disease: Short- and Long-term Modification by Non-genetic Risk Factors

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Naoyuki eSato

2013-11-01

Full Text Available It is well known that a specific set of genetic and non-genetic risk factors contributes to the onset of Alzheimer disease (AD. Non-genetic risk factors include diabetes, hypertension in mid-life, and probably dyslipidemia in mid-life. This review focuses on the vascular and metabolic components of non-genetic risk factors. The mechanisms whereby non-genetic risk factors modify cognitive dysfunction are divided into four components, short- and long-term effects of vascular and metabolic factors. These consist of 1 compromised vascular reactivity, 2 vascular lesions, 3 hypo/hyperglycemia, and 4 exacerbated AD histopathological features, respectively. Vascular factors compromise cerebrovascular reactivity in response to neuronal activity and also cause irreversible vascular lesions. On the other hand, representative short-term effects of metabolic factors on cognitive dysfunction occur due to hypoglycemia or hyperglycemia. Non-genetic risk factors also modify the pathological manifestations of AD in the long-term. Therefore, vascular and metabolic factors contribute to aggravation of cognitive dysfunction in AD through short-term and long-term effects. Beta-amyloid could be involved in both vascular and metabolic components. It might be beneficial to support treatment in AD patients by appropriate therapeutic management of non-genetic risk factors, considering the contributions of these four elements to the manifestation of cognitive dysfunction in individual patients, though all components are not always present. It should be clarified how these four components interact with each other. To answer this question, a clinical prospective study that follows up clinical features with respect to these four components: 1 functional MRI or SPECT for cerebrovascular reactivity, 2 MRI for ischemic lesions and atrophy, 3 clinical episodes of hypoglycemia and hyperglycemia, 4 amyloid-PET and tau-PET for pathological features of AD, would be required.

Roles of vascular and metabolic components in cognitive dysfunction of Alzheimer disease: short- and long-term modification by non-genetic risk factors.

Science.gov (United States)

Sato, Naoyuki; Morishita, Ryuichi

2013-11-05

It is well known that a specific set of genetic and non-genetic risk factors contributes to the onset of Alzheimer disease (AD). Non-genetic risk factors include diabetes, hypertension in mid-life, and probably dyslipidemia in mid-life. This review focuses on the vascular and metabolic components of non-genetic risk factors. The mechanisms whereby non-genetic risk factors modify cognitive dysfunction are divided into four components, short- and long-term effects of vascular and metabolic factors. These consist of (1) compromised vascular reactivity, (2) vascular lesions, (3) hypo/hyperglycemia, and (4) exacerbated AD histopathological features, respectively. Vascular factors compromise cerebrovascular reactivity in response to neuronal activity and also cause irreversible vascular lesions. On the other hand, representative short-term effects of metabolic factors on cognitive dysfunction occur due to hypoglycemia or hyperglycemia. Non-genetic risk factors also modify the pathological manifestations of AD in the long-term. Therefore, vascular and metabolic factors contribute to aggravation of cognitive dysfunction in AD through short-term and long-term effects. β-amyloid could be involved in both vascular and metabolic components. It might be beneficial to support treatment in AD patients by appropriate therapeutic management of non-genetic risk factors, considering the contributions of these four elements to the manifestation of cognitive dysfunction in individual patients, though all components are not always present. It should be clarified how these four components interact with each other. To answer this question, a clinical prospective study that follows up clinical features with respect to these four components: (1) functional MRI or SPECT for cerebrovascular reactivity, (2) MRI for ischemic lesions and atrophy, (3) clinical episodes of hypoglycemia and hyperglycemia, (4) amyloid-PET and tau-PET for pathological features of AD, would be required.

Individual genetic variations related to satiety and appetite control increase risk of obesity in preschool-age children in the STRONG kids program.

Science.gov (United States)

Wang, Yingying; Wang, Anthony; Donovan, Sharon M; Teran-Garcia, Margarita

2013-01-01

The burden of the childhood obesity epidemic is well recognized; nevertheless, the genetic markers and gene-environment interactions associated with the development of common obesity are still unknown. In this study, candidate genes associated to satiety and appetite control pathways with obesity-related traits were tested in Caucasian preschoolers from the STRONG Kids project. Eight genetic variants in genes related to obesity (BDNF, LEPR, FTO, PCSK1, POMC, TUB, LEP, and MC4R) were genotyped in 128 children from the STRONG Kids project (mean age 39.7 months). Data were analyzed for individual associations and to test for genetic predisposition scores (GPSs) with body mass index (BMI) and anthropometric traits (Z-scores, e.g. height-for-age Z-score, HAZ). Covariates included age, sex, and breastfeeding (BF) duration. Obesity and overweight prevalence was 6.3 and 19.5%, respectively, according to age- and sex-specific BMI percentiles. Individual genetic associations of MC4R and LEPR markers with HAZ were strengthened when BF duration was included as a covariate. Our GPSs show that, as the number of risk alleles increased, the risk of higher BMI and HAZ also increased. Overall, the GPSs assembled were able to explain 2-3% of the variability in BMI and HAZ phenotypes. Genetic associations with common obesity-related phenotypes were found in the STRONG Kids project. GPSs assembled for specific candidate genes were associated with BMI and HAZ phenotypes. © 2013 S. Karger AG, Basel.

Strong Genetic Overlap Between Executive Functions and Intelligence

OpenAIRE

Engelhardt, Laura E.; Mann, Frank D.; Briley, Daniel A.; Church, Jessica A.; Harden, K. Paige; Tucker-Drob, Elliot M.

2016-01-01

Executive functions (EFs) are cognitive processes that control, monitor, and coordinate more basic cognitive processes. EFs play instrumental roles in models of complex reasoning, learning, and decision-making, and individual differences in EFs have been consistently linked with individual differences in intelligence. By middle childhood, genetic factors account for a moderate proportion of the variance in intelligence, and these effects increase in magnitude through adolescence. Genetic infl...

Genetic and environmental components of female depression as a function of the severity of the disorder.

Science.gov (United States)

Rusby, James S M; Tasker, Fiona; Cherkas, Lynn

2016-10-01

Both clinical care and genome-wide studies need to account for levels of severity in the etiology of depression. The purpose of the study is to estimate the genetic and environmental components of female depression as a function of the severity of the disorder. A genetic and environmental model analysis of depression incidence was made using the IOP Depression Severity Measure (IDSM). Details of lifetime depression incidence were obtained by questionnaire from twins on the DTR registry. Data from 1449 matched female twin pairs in the age range 19-85 years in four ordinal categories of increasing severity were employed in the analysis. Estimates of additive and dominance genetic components of 27% and 25% were found when all three levels of depression were included, and near zero and 33% when the recurrent/severe level was excluded. Shared environmental effects were not significant in either case, but the estimate for random environmental effects was greater when the severe level was excluded. These results suggest that the incidence of severe depression is associated with homozygotic alleles and the less severe with heterozygotic alleles. This is in accord with the finding that the hereditary component of severe depression is relatively high and that milder forms are more dependent on life-time environmental factors. Such conclusions have clinical implications for the diagnosis and treatment of the disorder by practicing psychiatrists. They also lead to the importance of focusing future genome-wide and linkage studies on those females with severe levels of depression if progress in identifying genetic risk loci is to be made.

Genetic modification and genetic determinism

Science.gov (United States)

Resnik, David B; Vorhaus, Daniel B

2006-01-01

In this article we examine four objections to the genetic modification of human beings: the freedom argument, the giftedness argument, the authenticity argument, and the uniqueness argument. We then demonstrate that each of these arguments against genetic modification assumes a strong version of genetic determinism. Since these strong deterministic assumptions are false, the arguments against genetic modification, which assume and depend upon these assumptions, are therefore unsound. Serious discussion of the morality of genetic modification, and the development of sound science policy, should be driven by arguments that address the actual consequences of genetic modification for individuals and society, not by ones propped up by false or misleading biological assumptions. PMID:16800884

Genetic modification and genetic determinism

Directory of Open Access Journals (Sweden)

Vorhaus Daniel B

2006-06-01

Full Text Available Abstract In this article we examine four objections to the genetic modification of human beings: the freedom argument, the giftedness argument, the authenticity argument, and the uniqueness argument. We then demonstrate that each of these arguments against genetic modification assumes a strong version of genetic determinism. Since these strong deterministic assumptions are false, the arguments against genetic modification, which assume and depend upon these assumptions, are therefore unsound. Serious discussion of the morality of genetic modification, and the development of sound science policy, should be driven by arguments that address the actual consequences of genetic modification for individuals and society, not by ones propped up by false or misleading biological assumptions.

Identification of Methylosome Components as Negative Regulators of Plant Immunity Using Chemical Genetics.

Science.gov (United States)

Huang, Shuai; Balgi, Aruna; Pan, Yaping; Li, Meng; Zhang, Xiaoran; Du, Lilin; Zhou, Ming; Roberge, Michel; Li, Xin

2016-12-05

Nucleotide-binding leucine-rich repeat (NLR) proteins serve as immune receptors in both plants and animals. To identify components required for NLR-mediated immunity, we designed and carried out a chemical genetics screen to search for small molecules that can alter immune responses in Arabidopsis thaliana. From 13 600 compounds, we identified Ro 8-4304 that was able to specifically suppress the severe autoimmune phenotypes of chs3-2D (chilling sensitive 3, 2D), including the arrested growth morphology and heightened PR (Pathogenesis Related) gene expression. Further, six Ro 8-4304 insensitive mutants were uncovered from the Ro 8-4304-insensitive mutant (rim) screen using a mutagenized chs3-2D population. Positional cloning revealed that rim1 encodes an allele of AtICln (I, currents; Cl, chloride; n, nucleotide). Genetic and biochemical analysis demonstrated that AtICln is in the same protein complex with the methylosome components small nuclear ribonucleoprotein D3b (SmD3b) and protein arginine methyltransferase 5 (PRMT5), which are required for the biogenesis of small nuclear ribonucleoproteins (snRNPs) involved in mRNA splicing. Double mutant analysis revealed that SmD3b is also involved in the sensitivity to Ro 8-4304, and the prmt5-1 chs3-2D double mutant is lethal. Loss of AtICln, SmD3b, or PRMT5 function results in enhanced disease resistance against the virulent oomycete pathogen Hyaloperonospora arabidopsidis Noco2, suggesting that mRNA splicing plays a previously unknown negative role in plant immunity. The successful implementation of a high-throughput chemical genetic screen and the identification of a small-molecule compound affecting plant immunity indicate that chemical genetics is a powerful tool to study whole-organism plant defense pathways. Copyright © 2016 The Author. Published by Elsevier Inc. All rights reserved.

Genetic Components of Root Architecture Remodeling in Response to Salt Stress

KAUST Repository

Julkowska, Magdalena; Koevoets, Iko Tamar; Mol, Selena; Hoefsloot, Huub CJ; Feron, Richard; Tester, Mark A.; Keurentjes, Joost J.B.; Korte, Arthur; Haring, Michel A; de Boer, Gert-Jan; Testerink, Christa

2017-01-01

Salinity of the soil is highly detrimental to plant growth. Plants respond by a redistribution of root mass between main and lateral roots, yet the genetic machinery underlying this process is still largely unknown. Here, we describe the natural variation among 347 Arabidopsis thaliana accessions in root system architecture (RSA) and identify the traits with highest natural variation in their response to salt. Salt-induced changes in RSA were associated with 100 genetic loci using genome-wide association studies (GWAS). Two candidate loci associated with lateral root development were validated and further investigated. Changes in CYP79B2 expression in salt stress positively correlated with lateral root development in accessions, and cyp79b2 cyp79b3 double mutants developed fewer and shorter lateral roots under salt stress, but not in control conditions. By contrast, high HKT1 expression in the root repressed lateral root development, which could be partially rescued by addition of potassium. The collected data and Multi-Variate analysis of multiple RSA traits, available through the Salt_NV_Root App, capture root responses to salinity. Together, our results provide a better understanding of effective RSA remodeling responses, and the genetic components involved, for plant performance in stress conditions.

Genetic Components of Root Architecture Remodeling in Response to Salt Stress

KAUST Repository

Julkowska, Magdalena

2017-11-07

Salinity of the soil is highly detrimental to plant growth. Plants respond by a redistribution of root mass between main and lateral roots, yet the genetic machinery underlying this process is still largely unknown. Here, we describe the natural variation among 347 Arabidopsis thaliana accessions in root system architecture (RSA) and identify the traits with highest natural variation in their response to salt. Salt-induced changes in RSA were associated with 100 genetic loci using genome-wide association studies (GWAS). Two candidate loci associated with lateral root development were validated and further investigated. Changes in CYP79B2 expression in salt stress positively correlated with lateral root development in accessions, and cyp79b2 cyp79b3 double mutants developed fewer and shorter lateral roots under salt stress, but not in control conditions. By contrast, high HKT1 expression in the root repressed lateral root development, which could be partially rescued by addition of potassium. The collected data and Multi-Variate analysis of multiple RSA traits, available through the Salt_NV_Root App, capture root responses to salinity. Together, our results provide a better understanding of effective RSA remodeling responses, and the genetic components involved, for plant performance in stress conditions.

GENETIC ASPECTS OF AUTISM

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Anastas LAKOSKI

1997-06-01

Full Text Available In the first paper on the syndrome of autism, Kanner described it as innate and inborn. He drew attention to the abnormalities in infancy without evidence of prior normal development and the intellectual, non emotional qualities shown by many of the parents and grandparents. Subsequently, the supposed lack of parental warmth led many clinicians to abandon the notions of constitutional deficit in the child and instead to postulate a psychogenic origin etiology was likely, genetic factors probably did not play a major role. Attention was draw to the low rate of autism in siblings, the lack of chromosome anomalies, and the similarities with syndromes associated with known brain trauma. Although the rate of autism in siblings was indeed low, it was much higher than in the general population rate providing a strong pointer to the genetic factors. The recognition that this was so, associated with the parallel finding of apparently high familiar loading for language delay, stimulated the first, systematic, twin study of autism, which suggested a strong genetic component. Subsequent research has produced findings in the same direction, although many questions remain unanswered. In this paper the evidence that has accumulated on genetic influences on autism is summarized and the remained dilemmas on this field are discussed.

Research on application of complex-genetic algorithm in nuclear component optimal design

International Nuclear Information System (INIS)

He Shijing; Yan Changqi; Wang Jianjun; Wang Meng

2010-01-01

Complex algorithm is one of the most commonly used methods in the mechanical design optimization, such as the optimization of nuclear component. An improved method,complex-genetic algorithm(CGA), is developed based on traditional complex algorithm(TCA), in which the disadvantages of TCA have been overcome. An optimal calculation,which represents the pressurizer, is carried out in order to analyze the optimization capability of CGA. The results show that CGA has better optimizing performance than TCA. (authors)

Identification of genetic components involved in Lotus-endophyte interactions

DEFF Research Database (Denmark)

Zgadzaj, Rafal Lukasz

of growth hormones or nitrogen fixation. However, the genes involved in plant-endophyte interactions and bacterial accomodation within plant tissues are not known. In order to shed some light on such processes, an approach “one host-one endophyte” was chosen. The focus on a single plant species and a single......Endophytes are microorganisms capable of colonising plant tissues without inducing host defense responses. They have a large impact on plants, since they can modulate plant responses to pathogens, herbivores and environmental stress. They can also induce plant growth promotion through synthesis...... bacterial strain aimed at obtaining a reliable and easy to handle system for plant-microsymbiont interaction research. Two different methods were tested for their usefulness in identification of genetic components involved in plant-endophyte interactions. The first method was based on measuring growth...

Genetic variation of milk fatty acid composition between and within dairy cattle breeds

NARCIS (Netherlands)

Maurice - Van Eijndhoven, M.H.T.

2014-01-01

<strong>Abstract>

Maurice – Van Eijndhoven, M.H.T. (2014). Genetic variation of milk fatty acid composition between and within dairy cattle breeds. PhD thesis, Wageningen University, the Netherlands

Fat is one of the main components in bovine milk and comprises a large

Glioblastomas with oligodendroglial component - common origin of the different histological parts and genetic subclassification.

Science.gov (United States)

Klink, Barbara; Schlingelhof, Ben; Klink, Martin; Stout-Weider, Karen; Patt, Stephan; Schrock, Evelin

2010-01-01

Glioblastomas are the most common and most malignant brain tumors in adults. A small subgroup of glioblastomas contains areas with histological features of oligodendroglial differentiation (GBMO). Our objective was to genetically characterize the oligodendroglial and the astrocytic parts of GBMOs and correlate morphologic and genetic features with clinical data. The oligodendroglial and the "classic" glioblastoma parts of 13 GBMO were analyzed separately by interphase fluorescence in situ hybridization (FISH) on paraffin sections using a custom probe set (regions 1p, 1q, 7q, 10q, 17p, 19q, cen18, 21q) and by comparative genomic hybridization (CGH) of microdissected paraffin embedded tumor tissue. We identified four distinct genetic subtypes in 13 GBMOs: an "astrocytic" subtype (9/13) characterized by +7/-10; an "oligodendroglial" subtype with -1p/-19q (1/13); an "intermediate" subtype showing +7/-1p (1/13), and an "other" subtype having none of the former aberrations typical for gliomas (2/13). The different histological tumor parts of GBMO revealed common genetic changes in all tumors and showed additional aberrations specific for each part. Our findings demonstrate the monoclonal origin of GBMO followed by the development of the astrocytic and oligodendroglial components. The diagnostic determination of the genetic signatures may allow for a better prognostication of the patients.

Genetics Home Reference: complement component 8 deficiency

Science.gov (United States)

... in people with Hispanic, Japanese, or African Caribbean heritage, whereas type II primarily occurs in people of Northern European descent. Related Information What information about a genetic condition can statistics provide? Why are some genetic ...

Genetics of gallstone disease.

Directory of Open Access Journals (Sweden)

Mittal B

2002-04-01

Full Text Available Gallstone disease is a complex disorder where both environmental and genetic factors contribute towards susceptibility to the disease. Epidemiological and family studies suggest a strong genetic component in the causation of this disease. Several genetically derived phenotypes in the population are responsible for variations in lipoprotein types, which in turn affect the amount of cholesterol available in the gall bladder. The genetic polymorphisms in various genes for apo E, apo B, apo A1, LDL receptor, cholesteryl ester transfer and LDL receptor-associated protein have been implicated in gallstone formation. However, presently available information on genetic differences is not able to account for a large number of gallstone patients. The molecular studies in the animal models have not only confirmed the present paradigm of gallstone formation but also helped in identification of novel genes in humans, which might play an important role in pathogenesis of the disease. Precise understanding of such genes and their molecular mechanisms may provide the basis of new targets for rational drug designs and dietary interventions.

Estimates for Genetic Variance Components in Reciprocal Recurrent Selection in Populations Derived from Maize Single-Cross Hybrids

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Matheus Costa dos Reis

2014-01-01

Full Text Available This study was carried out to obtain the estimates of genetic variance and covariance components related to intra- and interpopulation in the original populations (C0 and in the third cycle (C3 of reciprocal recurrent selection (RRS which allows breeders to define the best breeding strategy. For that purpose, the half-sib progenies of intrapopulation (P11 and P22 and interpopulation (P12 and P21 from populations 1 and 2 derived from single-cross hybrids in the 0 and 3 cycles of the reciprocal recurrent selection program were used. The intra- and interpopulation progenies were evaluated in a 10×10 triple lattice design in two separate locations. The data for unhusked ear weight (ear weight without husk and plant height were collected. All genetic variance and covariance components were estimated from the expected mean squares. The breakdown of additive variance into intrapopulation and interpopulation additive deviations (στ2 and the covariance between these and their intrapopulation additive effects (CovAτ found predominance of the dominance effect for unhusked ear weight. Plant height for these components shows that the intrapopulation additive effect explains most of the variation. Estimates for intrapopulation and interpopulation additive genetic variances confirm that populations derived from single-cross hybrids have potential for recurrent selection programs.

Genetic component of sensitivity to heat stress for nonreturn rate of Brazilian Holstein cattle.

Science.gov (United States)

Santana, M L; Bignardi, A B; Stefani, G; El Faro, L

2017-08-01

The objectives of the present study were: 1) to investigate variation in the genetic component of heat stress for nonreturn rate at 56 days after first artificial insemination (NR56); 2) to identify and characterize the genotype by environment interaction (G × E) due to heat stress for NR56 of Brazilian Holstein cattle. A linear random regression model (reaction norm model) was applied to 51,748 NR56 records of 28,595 heifers and multiparous cows. The decline in NR56 due to heat stress was more pronounced in milking cows compared to heifers. The age of females at first artificial insemination and temperature-humidity index (THI) exerted an important influence on the genetic parameters of NR56. Several evidence of G × E on NR56 were found as the high slope/intercept ratio and frequent intersection of reaction norms. Additionally, the genetic correlation between NR56 at opposite extremes of the THI scale reached estimates below zero, indicating that few of the same genes are responsible for NR56 under conditions of thermoneutrality and heat stress. The genetic evaluation and selection for NR56 in Holstein cattle reared under (sub)tropical conditions should therefore take into consideration the genetic variation on age at insemination and G × E due to heat stress. Copyright © 2017 Elsevier Inc. All rights reserved.

The rRNA methyltransferase Bud23 shows functional interaction with components of the SSU processome and RNase MRP.

Science.gov (United States)

Sardana, Richa; White, Joshua P; Johnson, Arlen W

2013-06-01

Bud23 is responsible for the conserved methylation of G1575 of 18S rRNA, in the P-site of the small subunit of the ribosome. bud23Δ mutants have severely reduced small subunit levels and show a general failure in cleavage at site A2 during rRNA processing. Site A2 is the primary cleavage site for separating the precursors of 18S and 25S rRNAs. Here, we have taken a genetic approach to identify the functional environment of BUD23. We found mutations in UTP2 and UTP14, encoding components of the SSU processome, as spontaneous suppressors of a bud23Δ mutant. The suppressors improved growth and subunit balance and restored cleavage at site A2. In a directed screen of 50 ribosomal trans-acting factors, we identified strong positive and negative genetic interactions with components of the SSU processome and strong negative interactions with components of RNase MRP. RNase MRP is responsible for cleavage at site A3 in pre-rRNA, an alternative cleavage site for separating the precursor rRNAs. The strong negative genetic interaction between RNase MRP mutants and bud23Δ is likely due to the combined defects in cleavage at A2 and A3. Our results suggest that Bud23 plays a role at the time of A2 cleavage, earlier than previously thought. The genetic interaction with the SSU processome suggests that Bud23 could be involved in triggering disassembly of the SSU processome, or of particular subcomplexes of the processome.

Diet, Cardiometabolic Factors and Type-2 Diabetes Mellitus: The Role of Genetics.

Science.gov (United States)

Marcadenti, Aline

2016-01-01

Type 2 diabetes mellitus (T2DM) is a highly prevalent condition and is associated with a number of metabolic risk factors such as excess of weight, impaired lipid profile and higher levels of blood pressure. As other complex diseases, it is strongly related to an environmental component such as sedentarism and unhealthy diet, and also to a genetic component. A cluster of variants (polymorphisms) in a large number of genes seem to interact with nutrients/dietary factors in modulating cardiometabolic parameters in healthy individuals. The role of total calories intake and also different kind of carbohydrates and dietary fats in worsening the excess of weight and/or metabolic profile in patients with diabetes is well known, but the extent to which genetic factors can modify these associations is not yet fully understood. Therefore, the aim of this mini-review is to discuss the interaction of genetics and diet in the T2DM setting, since both are strongly involved in the genesis and development of the disease.

Early environmental exposures influence schizophrenia expression even in the presence of strong genetic predisposition.

Science.gov (United States)

Husted, Janice A; Ahmed, Rashid; Chow, Eva W C; Brzustowicz, Linda M; Bassett, Anne S

2012-05-01

There are few studies of environmental factors in familial forms of schizophrenia. We investigated whether childhood adversity or environmental factors were associated with schizophrenia in a familial sample where schizophrenia is associated with the NOSA1P gene. We found that a cumulative adversity index including childhood illness, family instability and cannabis use was significantly associated with narrow schizophrenia, independent of NOSA1P risk genotype, previously measured childhood trauma, covariates and familial clustering (adjusted odds ratio (95% confidence interval)=1.55 (1.01, 2.38)). The results provide further support that early environmental exposures influence schizophrenia expression even in the presence of strong genetic predisposition. Copyright © 2012 Elsevier B.V. All rights reserved.

Understanding the cognitive and genetic underpinnings of procrastination: Evidence for shared genetic influences with goal management and executive function abilities.

Science.gov (United States)

Gustavson, Daniel E; Miyake, Akira; Hewitt, John K; Friedman, Naomi P

2015-12-01

Previous research has suggested that individual differences in procrastination are tied to everyday goal-management abilities, but little research has been conducted on specific cognitive abilities that may underlie tendencies for procrastination, such as executive functions (EFs). In this study, we used behavioral genetics methodology to investigate 2 hypotheses about the relationships between procrastination and EF ability: (a) that procrastination is negatively correlated with general EF ability, and (b) that this relationship is due to the genetic components of procrastination that are most related to other everyday goal-management abilities. The results confirmed both of these hypotheses. Procrastination was related to worse general EF ability at both the phenotypic and genetic levels, and this relationship was due to the component of procrastination shared with self-report measures of everyday goal-management failures. These results were observed even after controlling for potential self-report biases stemming from the urge to respond in a socially desirable manner. Together, these findings provide strong evidence for growing theories of procrastination emphasizing the importance of goal-related cognitive abilities and further highlight important genetic influences that underlie procrastination. (c) 2015 APA, all rights reserved).

Telomerase RNA Component (TERC) genetic variants interact with the mediterranean diet modifying the inflammatory status and its relationship with aging: CORDIOPREV study

Science.gov (United States)

Background: Leukocyte telomere length (LTL) attrition has been associated with age-related diseases. Telomerase RNA Component (TERC) genetic variants have been associated with LTL; whereas fatty acids (FAs) can interact with genetic factors and influence in aging. We explore whether variability at t...

Two genetic loci produce distinct carbohydrate-rich structural components of the Pseudomonas aeruginosa biofilm matrix.

Science.gov (United States)

Friedman, Lisa; Kolter, Roberto

2004-07-01

Pseudomonas aeruginosa forms biofilms, which are cellular aggregates encased in an extracellular matrix. Molecular genetics studies of three common autoaggregative phenotypes, namely wrinkled colonies, pellicles, and solid-surface-associated biofilms, led to the identification of two loci, pel and psl, that are involved in the production of carbohydrate-rich components of the biofilm matrix. The pel gene cluster is involved in the production of a glucose-rich matrix material in P. aeruginosa strain PA14 (L. Friedman and R. Kolter, Mol. Microbiol. 51:675-690, 2004). Here we investigate the role of the pel gene cluster in P. aeruginosa strain ZK2870 and identify a second genetic locus, termed psl, involved in the production of a mannose-rich matrix material. The 11 predicted protein products of the psl genes are homologous to proteins involved in carbohydrate processing. P. aeruginosa is thus able to produce two distinct carbohydrate-rich matrix materials. Either carbohydrate-rich matrix component appears to be sufficient for mature biofilm formation, and at least one of them is required for mature biofilm formation in P. aeruginosa strains PA14 and ZK2870. Copyright 2004 American Society for Microbiology

Glioblastomas with Oligodendroglial Component – Common Origin of the Different Histological Parts and Genetic Subclassification

Science.gov (United States)

Klink, Barbara; Schlingelhof, Ben; Klink, Martin; Stout-Weider, Karen; Patt, Stephan; Schrock, Evelin

2010-01-01

Background: Glioblastomas are the most common and most malignant brain tumors in adults. A small subgroup of glioblastomas contains areas with histological features of oligodendroglial differentiation (GBMO). Our objective was to genetically characterize the oligodendroglial and the astrocytic parts of GBMOs and correlate morphologic and genetic features with clinical data. Methods: The oligodendroglial and the “classic” glioblastoma parts of 13 GBMO were analyzed separately by interphase fluorescence in situ hybridization (FISH) on paraffin sections using a custom probe set (regions 1p, 1q, 7q, 10q, 17p, 19q, cen18, 21q) and by comparative genomic hybridization (CGH) of microdissected paraffin embedded tumor tissue. Results: We identified four distinct genetic subtypes in 13 GBMOs: an “astrocytic” subtype (9/13) characterized by +7/−10; an “oligodendroglial” subtype with −1p/−19q (1/13); an “intermediate” subtype showing +7/−1p (1/13), and an “other” subtype having none of the former aberrations typical for gliomas (2/13). The different histological tumor parts of GBMO revealed common genetic changes in all tumors and showed additional aberrations specific for each part. Conclusion: Our findings demonstrate the monoclonal origin of GBMO followed by the development of the astrocytic and oligodendroglial components. The diagnostic determination of the genetic signatures may allow for a better prognostication of the patients. PMID:20966543

The genetic component of human longevity

DEFF Research Database (Denmark)

Dato, Serena; Thinggaard, Mette Sørensen; De Rango, Francesco

2018-01-01

In human longevity studies, single nucleotide polymorphism (SNP) analysis identified a large number of genetic variants with small effects, yet not easily replicable in different populations. New insights may come from the combined analysis of different SNPs, especially when grouped by metabolic...... pathway. We applied this approach to study the joint effect on longevity of SNPs belonging to three candidate pathways, the insulin/insulin-like growth factor signalling (IIS), DNA repair and pro/antioxidant. We analysed data from 1,058 tagging SNPs in 140 genes, collected in 1825 subjects (1......, was further found influencing longitudinal survival in nonagenarian females (p = .026). Results here presented highlight the validity of SNP-SNP interactions analyses for investigating the genetics of human longevity, confirming previously identified markers but also pointing to novel genes as central nodes...

Plasmons in strong superconductors

International Nuclear Information System (INIS)

Baldo, M.; Ducoin, C.

2011-01-01

We present a study of the possible plasmon excitations that can occur in systems where strong superconductivity is present. In these systems the plasmon energy is comparable to or smaller than the pairing gap. As a prototype of these systems we consider the proton component of Neutron Star matter just below the crust when electron screening is not taken into account. For the realistic case we consider in detail the different aspects of the elementary excitations when the proton, electron components are considered within the Random-Phase Approximation generalized to the superfluid case, while the influence of the neutron component is considered only at qualitative level. Electron screening plays a major role in modifying the proton spectrum and spectral function. At the same time the electron plasmon is strongly modified and damped by the indirect coupling with the superfluid proton component, even at moderately low values of the gap. The excitation spectrum shows the interplay of the different components and their relevance for each excitation modes. The results are relevant for neutrino physics and thermodynamical processes in neutron stars. If electron screening is neglected, the spectral properties of the proton component show some resemblance with the physical situation in high-T c superconductors, and we briefly discuss similarities and differences in this connection. In a general prospect, the results of the study emphasize the role of Coulomb interaction in strong superconductors.

Insight into the genetic components of community genetics: QTL mapping of insect association in a fast-growing forest tree.

Directory of Open Access Journals (Sweden)

Jennifer DeWoody

Full Text Available Identifying genetic sequences underlying insect associations on forest trees will improve the understanding of community genetics on a broad scale. We tested for genomic regions associated with insects in hybrid poplar using quantitative trait loci (QTL analyses conducted on data from a common garden experiment. The F2 offspring of a hybrid poplar (Populus trichocarpa x P. deltoides cross were assessed for seven categories of insect leaf damage at two time points, June and August. Positive and negative correlations were detected among damage categories and between sampling times. For example, sap suckers on leaves in June were positively correlated with sap suckers on leaves (P<0.001 but negatively correlated with skeletonizer damage (P<0.01 in August. The seven forms of leaf damage were used as a proxy for seven functional groups of insect species. Significant variation in insect association occurred among the hybrid offspring, including transgressive segregation of susceptibility to damage. NMDS analyses revealed significant variation and modest broad-sense heritability in insect community structure among genets. QTL analyses identified 14 genomic regions across 9 linkage groups that correlated with insect association. We used three genomics tools to test for putative mechanisms underlying the QTL. First, shikimate-phenylpropanoid pathway genes co-located to 9 of the 13 QTL tested, consistent with the role of phenolic glycosides as defensive compounds. Second, two insect association QTL corresponded to genomic hotspots for leaf trait QTL as identified in previous studies, indicating that, in addition to biochemical attributes, leaf morphology may influence insect preference. Third, network analyses identified categories of gene models over-represented in QTL for certain damage types, providing direction for future functional studies. These results provide insight into the genetic components involved in insect community structure in a fast

BREEDING AND GENETICS SYMPOSIUM: Resilience and lessons from studies in genetics of heat stress.

Science.gov (United States)

Misztal, I

2017-04-01

Production environments are expected to change, mostly to a hotter climate but also possibly more extreme and drier. Can the current generation of farm animals cope with the changes or should it be specifically selected for changing conditions? In general, genetic selection produces animals with a smaller environmental footprint but also with smaller environmental flexibility. Some answers are coming from heat-stress research across species, with heat tolerance partly understood as a greater environmental flexibility. Specific studies in various species show the complexities of defining and selecting for heat tolerance. In Holsteins, the genetic component for effect of heat stress on production approximately doubles in second and quadruples in third parity. Cows with elevated body temperature have the greatest production under heat stress but probably are at risk for increased mortality. In hot but less intensive environments, the effect of heat stress on production is minimal, although the negative effect on fertility remains. Mortality peaks under heat stress and increases with parity. In Angus, the effect of heat stress is stronger only in selected regions, probably because of adaptation of calving seasons to local conditions and crossbreeding. Genetically, the direct effect shows variability because of heat stress, but the maternal effect does not, probably because dams shield calves from environmental challenges. In pigs, the effect of heat stress is strong for commercial farms but almost nothing for nucleus farms, which have lower pig density and better heat abatement. Under intensive management, heat stress is less evident in drier environments because of more efficient cooling. A genetic component of heat stress exists, but it is partly masked by improving management and selection based on data from elite farms. Genetic selection may provide superior identification of heat-tolerant animals, but a few cycles may be needed for clear results. Also, simple

The genetic component of human longevity

DEFF Research Database (Denmark)

Dato, Serena; Thinggaard, Mette Sørensen; De Rango, Francesco

2018-01-01

In human longevity studies, single nucleotide polymorphism (SNP) analysis identified a large number of genetic variants with small effects, yet not easily replicable in different populations. New insights may come from the combined analysis of different SNPs, especially when grouped by metabolic ...

Genetic Analysis of Seed Yield Components and its Association with Forage Production in Wild and Cultivated Species of Sainfoin

Directory of Open Access Journals (Sweden)

A. Najafipoor

2017-02-01

Full Text Available Little is known about genetic variation of seed related traits and their association with forage characters in sainfoin. In order to investigate the variation and relationship among seed yield and its components, 93 genotypes from 21 wild and cultivated species of genus Onobrychis were evaluated using a randomized complete block design with four replications at Isfahan University of Technology Research Farm, Isfahan, Iran. Analysis of variance showed that there was significant difference among genotypes, indicating existence of considerable genetic variation in this germplasm. Panicle fertility and panicle length had the most variation in cultivated and the wild genotypes, respectively. Results of correlation analysis showed that seed yield was positively correlated with number of stems per plant and number of seeds per panicle and negatively correlated with panicle length and days to 50% flowering. Seed yield had positive correlation with forage yield in wild species while this correlation was not significant in cultivated one. Cluster analysis classified the genotypes into three groups which separate wild and cultivated species. Based on principal component analysis the first component was related to seed yield and the second one was related to components of forage yield which can be used for selection of high forage and seed yielding genotypes.

Genetic and environmental influences on risk of death due to infections assessed in Danish twins, 1943-2001

DEFF Research Database (Denmark)

Obel, Niels; Christensen, Kaare; Petersen, Inge

2010-01-01

Genetic differences have been proposed to play a strong role in risk of death from infectious diseases. The study base of 44,005 included all same-sex twin pairs born in 1870-2001, with both twins alive on January 1, 1943, or those born thereafter. Cause of death was obtained from the Danish Cause...... from infectious diseases could be demonstrated, the absolute effect of the genetic component on mortality was small....... genetic influence on the risk of death...

Strong resilience of soil respiration components to drought-induced die-off resulting in forest secondary succession.

Science.gov (United States)

Barba, Josep; Curiel Yuste, Jorge; Poyatos, Rafael; Janssens, Ivan A; Lloret, Francisco

2016-09-01

How forests cope with drought-induced perturbations and how the dependence of soil respiration on environmental and biological drivers is affected in a warming and drying context are becoming key questions. The aims of this study were to determine whether drought-induced die-off and forest succession were reflected in soil respiration and its components and to determine the influence of climate on the soil respiration components. We used the mesh exclusion method to study seasonal variations in soil respiration (R S) and its components: heterotrophic (R H) and autotrophic (R A) [further split into fine root (R R) and mycorrhizal respiration (R M)] in a mixed Mediterranean forest where Scots pine (Pinus sylvestris L.) is undergoing a drought-induced die-off and is being replaced by holm oak (Quercus ilex L.). Drought-induced pine die-off was not reflected in R S nor in its components, which denotes a high functional resilience of the plant and soil system to pine die-off. However, the succession from Scots pine to holm oak resulted in a reduction of R H and thus in an important decrease of total respiration (R S was 36 % lower in holm oaks than in non-defoliated pines). Furthermore, R S and all its components were strongly regulated by soil water content-and-temperature interaction. Since Scots pine die-off and Quercus species colonization seems to be widely occurring at the driest limit of the Scots pine distribution, the functional resilience of the soil system over die-off and the decrease of R S from Scots pine to holm oak could have direct consequences for the C balance of these ecosystems.

Nonlinear fitness-space-structure adaptation and principal component analysis in genetic algorithms: an application to x-ray reflectivity analysis

International Nuclear Information System (INIS)

Tiilikainen, J; Tilli, J-M; Bosund, V; Mattila, M; Hakkarainen, T; Airaksinen, V-M; Lipsanen, H

2007-01-01

Two novel genetic algorithms implementing principal component analysis and an adaptive nonlinear fitness-space-structure technique are presented and compared with conventional algorithms in x-ray reflectivity analysis. Principal component analysis based on Hessian or interparameter covariance matrices is used to rotate a coordinate frame. The nonlinear adaptation applies nonlinear estimates to reshape the probability distribution of the trial parameters. The simulated x-ray reflectivity of a realistic model of a periodic nanolaminate structure was used as a test case for the fitting algorithms. The novel methods had significantly faster convergence and less stagnation than conventional non-adaptive genetic algorithms. The covariance approach needs no additional curve calculations compared with conventional methods, and it had better convergence properties than the computationally expensive Hessian approach. These new algorithms can also be applied to other fitting problems where tight interparameter dependence is present

Environmental variation partitioned into separate heritable components

DEFF Research Database (Denmark)

Ørsted, Michael; Rohde, Palle Duun; Hoffmann, Ary A

2018-01-01

Trait variation is normally separated into genetic and environmental components, yet genetic factors also control the expression of environmental variation, encompassing plasticity across environmental gradients and within-environment responses. We defined four components of environmental variation......: plasticity across environments, variability in plasticity, variation within environments, and differences in within-environment variation across environments. We assessed these components for cold tolerance across five rearing temperatures using the Drosophila melanogaster Genetic Reference Panel (DGRP...

Genetic and phenotypic variance and covariance components for methane emission and postweaning traits in Angus cattle.

Science.gov (United States)

Donoghue, K A; Bird-Gardiner, T; Arthur, P F; Herd, R M; Hegarty, R F

2016-04-01

Ruminants contribute 80% of the global livestock greenhouse gas (GHG) emissions mainly through the production of methane, a byproduct of enteric microbial fermentation primarily in the rumen. Hence, reducing enteric methane production is essential in any GHG emissions reduction strategy in livestock. Data on 1,046 young bulls and heifers from 2 performance-recording research herds of Angus cattle were analyzed to provide genetic and phenotypic variance and covariance estimates for methane emissions and production traits and to examine the interrelationships among these traits. The cattle were fed a roughage diet at 1.2 times their estimated maintenance energy requirements and measured for methane production rate (MPR) in open circuit respiration chambers for 48 h. Traits studied included DMI during the methane measurement period, MPR, and methane yield (MY; MPR/DMI), with means of 6.1 kg/d (SD 1.3), 132 g/d (SD 25), and 22.0 g/kg (SD 2.3) DMI, respectively. Four forms of residual methane production (RMP), which is a measure of actual minus predicted MPR, were evaluated. For the first 3 forms, predicted MPR was calculated using published equations. For the fourth (RMP), predicted MPR was obtained by regression of MPR on DMI. Growth and body composition traits evaluated were birth weight (BWT), weaning weight (WWT), yearling weight (YWT), final weight (FWT), and ultrasound measures of eye muscle area, rump fat depth, rib fat depth, and intramuscular fat. Heritability estimates were moderate for MPR (0.27 [SE 0.07]), MY (0.22 [SE 0.06]), and the RMP traits (0.19 [SE 0.06] for each), indicating that genetic improvement to reduce methane emissions is possible. The RMP traits and MY were strongly genetically correlated with each other (0.99 ± 0.01). The genetic correlation of MPR with MY as well as with the RMP traits was moderate (0.32 to 0.63). The genetic correlation between MPR and the growth traits (except BWT) was strong (0.79 to 0.86). These results indicate that

Is It Possible to Predict Strong Earthquakes?

Science.gov (United States)

Polyakov, Y. S.; Ryabinin, G. V.; Solovyeva, A. B.; Timashev, S. F.

2015-07-01

The possibility of earthquake prediction is one of the key open questions in modern geophysics. We propose an approach based on the analysis of common short-term candidate precursors (2 weeks to 3 months prior to strong earthquake) with the subsequent processing of brain activity signals generated in specific types of rats (kept in laboratory settings) who reportedly sense an impending earthquake a few days prior to the event. We illustrate the identification of short-term precursors using the groundwater sodium-ion concentration data in the time frame from 2010 to 2014 (a major earthquake occurred on 28 February 2013) recorded at two different sites in the southeastern part of the Kamchatka Peninsula, Russia. The candidate precursors are observed as synchronized peaks in the nonstationarity factors, introduced within the flicker-noise spectroscopy framework for signal processing, for the high-frequency component of both time series. These peaks correspond to the local reorganizations of the underlying geophysical system that are believed to precede strong earthquakes. The rodent brain activity signals are selected as potential "immediate" (up to 2 weeks) deterministic precursors because of the recent scientific reports confirming that rodents sense imminent earthquakes and the population-genetic model of K irshvink (Soc Am 90, 312-323, 2000) showing how a reliable genetic seismic escape response system may have developed over the period of several hundred million years in certain animals. The use of brain activity signals, such as electroencephalograms, in contrast to conventional abnormal animal behavior observations, enables one to apply the standard "input-sensor-response" approach to determine what input signals trigger specific seismic escape brain activity responses.

Variance components and genetic parameters for body weight and ...

African Journals Online (AJOL)

model included a direct as well as a maternal additive genetic effect, while only the direct additive genetic eff'ect had a sig- .... deviations from the log likelihood value obtained under the ... (1995).lt would therefore be fair to assume that a.

Development of a genetic sexing strain in Bactrocera carambolae (Diptera: Tephritidae) by introgression of sex sorting components from B. dorsalis, Salaya1 strain.

Science.gov (United States)

Isasawin, Siriwan; Aketarawong, Nidchaya; Lertsiri, Sittiwat; Thanaphum, Sujinda

2014-01-01

The carambola fruit fly, Bactrocera carambolae Drew & Hancock is a high profile key pest that is widely distributed in the southwestern ASEAN region. In addition, it has trans-continentally invaded Suriname, where it has been expanding east and southward since 1975. This fruit fly belongs to Bactrocera dorsalis species complex. The development and application of a genetic sexing strain (Salaya1) of B. dorsalis sensu stricto (s.s.) (Hendel) for the sterile insect technique (SIT) has improved the fruit fly control. However, matings between B. dorsalis s.s. and B. carambolae are incompatible, which hinder the application of the Salaya1 strain to control the carambola fruit fly. To solve this problem, we introduced genetic sexing components from the Salaya1 strain into the B. carambolae genome by interspecific hybridization. Morphological characteristics, mating competitiveness, male pheromone profiles, and genetic relationships revealed consistencies that helped to distinguish Salaya1 and B. carambolae strains. A Y-autosome translocation linking the dominant wild-type allele of white pupae gene and a free autosome carrying a recessive white pupae homologue from the Salaya1 strain were introgressed into the gene pool of B. carambolae. A panel of Y-pseudo-linked microsatellite loci of the Salaya1 strain served as markers for the introgression experiments. This resulted in a newly derived genetic sexing strain called Salaya5, with morphological characteristics corresponding to B. carambolae. The rectal gland pheromone profile of Salaya5 males also contained a distinctive component of B. carambolae. Microsatellite DNA analyses confirmed the close genetic relationships between the Salaya5 strain and wild B. carambolae populations. Further experiments showed that the sterile males of Salaya5 can compete with wild males for mating with wild females in field cage conditions. Introgression of sex sorting components from the Salaya1 strain to a closely related B. carambolae

Genetic variance components for residual feed intake and feed ...

African Journals Online (AJOL)

Feeding costs of animals is a major determinant of profitability in livestock production enterprises. Genetic selection to improve feed efficiency aims to reduce feeding cost in beef cattle and thereby improve profitability. This study estimated genetic (co)variances between weaning weight and other production, reproduction ...

Radiation-induced structural transitions in composite materials with strong interaction of polymer components

International Nuclear Information System (INIS)

Zaikin, Yu.A.; Koztaeva, U.P.

2002-01-01

In earlier papers the internal friction (IF) method was applied to studies of structural relaxation in different types of polymer-based composite materials (glass-cloth, paper-based and foiled laminates impregnated by epoxy and phenolic resins) irradiated by 2 MeV electrons in the dose range of 0.1-50.0 MGy. Selectivity and high sensibility of the internal friction method allowed to distinguish glassy transitions in different structural components of the composites. The relaxation processes observed were identified and attributed to structural alterations in the polymer filler, the binder and the boundary layers. It was shown that changes in the parameters of relaxation maximums during irradiation can be considered as quantitative characteristics for the degree of radiation-induced degradation or cross-linking of polymer molecules. This paper deals with specific features of IF spectra in paper-based laminates where both the filler fibers and the binder are strongly interacting polymers. Anisotropy of viscous and elastic properties is very weak for this kind of materials, so that IF measurements give nearly the same result independently on the filler fiber orientation in the sample. The main reasons for it are the rigid chain structure of fillers (polyethylene-terephthalate and cellulose) and the good adhesion strengthened by diffusion of the epoxy or phenolic binder to defect regions of the filler.The IF temperature dependence observed in paper-based laminates is represented by superposition of two very broad relaxation maximums associated with transitions from glassy to high-elastic state in structural components, each based on one of the polymers. The inflection points characteristic for IF temperature dependence in paper-based laminates give a reason to treat them as a superposition of α-peaks associated with transitions from glassy to high-elastic state in structural components of a composite based on the binder and the filler, respectively. Another

Impact of strong selection for the PrP major gene on genetic variability of four French sheep breeds (Open Access publication

Directory of Open Access Journals (Sweden)

Pantano Thais

2008-11-01

Full Text Available Abstract Effective selection on the PrP gene has been implemented since October 2001 in all French sheep breeds. After four years, the ARR "resistant" allele frequency increased by about 35% in young males. The aim of this study was to evaluate the impact of this strong selection on genetic variability. It is focussed on four French sheep breeds and based on the comparison of two groups of 94 animals within each breed: the first group of animals was born before the selection began, and the second, 3–4 years later. Genetic variability was assessed using genealogical and molecular data (29 microsatellite markers. The expected loss of genetic variability on the PrP gene was confirmed. Moreover, among the five markers located in the PrP region, only the three closest ones were affected. The evolution of the number of alleles, heterozygote deficiency within population, expected heterozygosity and the Reynolds distances agreed with the criteria from pedigree and pointed out that neutral genetic variability was not much affected. This trend depended on breed, i.e. on their initial states (population size, PrP frequencies and on the selection strategies for improving scrapie resistance while carrying out selection for production traits.

Trill performance components vary with age, season, and motivation in the banded wren

OpenAIRE

Vehrencamp, S. L.; Yantachka, J.; Hall, M. L.; de Kort, S. R.

2012-01-01

Acoustic displays with difficult-to-execute sounds are often subject to strong sexual selection, because performance levels are related to the sender’s condition or genetic quality. Performance may also vary with age, breeding stage, and motivation related to social context. We focused on within-male variation in four components of trill performance in banded wren (Thryophilus pleurostictus) songs: note consistency, frequency bandwidth, note rate and vocal deviation. The latter is a composite...

The Breda Study: Search for genetic factors involved in type 2 diabetes mellitus in a defined Dutch population

NARCIS (Netherlands)

Tilburg, Jonathan Hendrik Otto van

2002-01-01

Little is known about the nature of genetic variation underlying complex diseases in humans. The recognition that susceptibility to type 2 diabetes mellitus has a strong inherited component provides a mechanism for developing the molecular understanding of the pathogenesis of type 2 diabetes

Genetic basis of type 2 diabetes mellitus: implications for therapy

DEFF Research Database (Denmark)

Wolford, Johanna K; de Courten, Barbora

2004-01-01

influenced by the relatively recent changes in diet and physical activity levels. There is also strong evidence supporting a genetic component to type 2 diabetes susceptibility and several genes underlying monogenic forms of diabetes have already been identified. However, common type 2 diabetes is likely...... and in the responsiveness to pharmacologic therapies, identification and characterization of the genetic variants underlying type 2 diabetes susceptibility will be important in the development of individualized treatment. Findings from linkage analyses, candidate gene studies, and animal models will be valuable...... in the identification of novel pathways involved in the regulation of glucose homeostasis, and will augment our understanding of the gene-gene and gene-environment interactions, which impact on type 2 diabetes etiology and pathogenesis. In addition, identification of genetic variants that determine differences...

A genome-wide association study identifies rs2000999 as a strong genetic determinant of circulating haptoglobin levels.

Directory of Open Access Journals (Sweden)

Philippe Froguel

Full Text Available Haptoglobin is an acute phase inflammatory marker. Its main function is to bind hemoglobin released from erythrocytes to aid its elimination, and thereby haptoglobin prevents the generation of reactive oxygen species in the blood. Haptoglobin levels have been repeatedly associated with a variety of inflammation-linked infectious and non-infectious diseases, including malaria, tuberculosis, human immunodeficiency virus, hepatitis C, diabetes, carotid atherosclerosis, and acute myocardial infarction. However, a comprehensive genetic assessment of the inter-individual variability of circulating haptoglobin levels has not been conducted so far.We used a genome-wide association study initially conducted in 631 French children followed by a replication in three additional European sample sets and we identified a common single nucleotide polymorphism (SNP, rs2000999 located in the Haptoglobin gene (HP as a strong genetic predictor of circulating Haptoglobin levels (P(overall = 8.1 × 10(-59, explaining 45.4% of its genetic variability (11.8% of Hp global variance. The functional relevance of rs2000999 was further demonstrated by its specific association with HP mRNA levels (β = 0.23 ± 0.08, P = 0.007. Finally, SNP rs2000999 was associated with decreased total and low-density lipoprotein cholesterol in 8,789 European children (P(total cholesterol = 0.002 and P(LDL = 0.0008.Given the central position of haptoglobin in many inflammation-related metabolic pathways, the relevance of rs2000999 genotyping when evaluating haptoglobin concentration should be further investigated in order to improve its diagnostic/therapeutic and/or prevention impact.

Principal component approach in variance component estimation for international sire evaluation

Directory of Open Access Journals (Sweden)

Jakobsen Jette

2011-05-01

Full Text Available Abstract Background The dairy cattle breeding industry is a highly globalized business, which needs internationally comparable and reliable breeding values of sires. The international Bull Evaluation Service, Interbull, was established in 1983 to respond to this need. Currently, Interbull performs multiple-trait across country evaluations (MACE for several traits and breeds in dairy cattle and provides international breeding values to its member countries. Estimating parameters for MACE is challenging since the structure of datasets and conventional use of multiple-trait models easily result in over-parameterized genetic covariance matrices. The number of parameters to be estimated can be reduced by taking into account only the leading principal components of the traits considered. For MACE, this is readily implemented in a random regression model. Methods This article compares two principal component approaches to estimate variance components for MACE using real datasets. The methods tested were a REML approach that directly estimates the genetic principal components (direct PC and the so-called bottom-up REML approach (bottom-up PC, in which traits are sequentially added to the analysis and the statistically significant genetic principal components are retained. Furthermore, this article evaluates the utility of the bottom-up PC approach to determine the appropriate rank of the (covariance matrix. Results Our study demonstrates the usefulness of both approaches and shows that they can be applied to large multi-country models considering all concerned countries simultaneously. These strategies can thus replace the current practice of estimating the covariance components required through a series of analyses involving selected subsets of traits. Our results support the importance of using the appropriate rank in the genetic (covariance matrix. Using too low a rank resulted in biased parameter estimates, whereas too high a rank did not result in

Population genomic analysis suggests strong influence of river network on spatial distribution of genetic variation in invasive saltcedar across the southwestern United States

Science.gov (United States)

Lee, Soo-Rang; Jo, Yeong-Seok; Park, Chan-Ho; Friedman, Jonathan M.; Olson, Matthew S.

2018-01-01

Understanding the complex influences of landscape and anthropogenic elements that shape the population genetic structure of invasive species provides insight into patterns of colonization and spread. The application of landscape genomics techniques to these questions may offer detailed, previously undocumented insights into factors influencing species invasions. We investigated the spatial pattern of genetic variation and the influences of landscape factors on population similarity in an invasive riparian shrub, saltcedar (Tamarix L.) by analysing 1,997 genomewide SNP markers for 259 individuals from 25 populations collected throughout the southwestern United States. Our results revealed a broad-scale spatial genetic differentiation of saltcedar populations between the Colorado and Rio Grande river basins and identified potential barriers to population similarity along both river systems. River pathways most strongly contributed to population similarity. In contrast, low temperature and dams likely served as barriers to population similarity. We hypothesize that large-scale geographic patterns in genetic diversity resulted from a combination of early introductions from distinct populations, the subsequent influence of natural selection, dispersal barriers and founder effects during range expansion.

[Nutritional components and sub-chronic toxicity of genetically modified rice expressing human lactoferrin].

Science.gov (United States)

Hu, Yichun; Piao, Jianhua; Yang, Xiaoguang

2012-01-01

To compare the nutritional components of genetically modified rice expressing human lactoferrin (hLf) with its parental rice, and to observe the sub-chronic toxicity of hLf rice. The nutritional components of hLf rice and its parental rice were determined by the National Standard Methods. Eighty weanling Wistar rats were randomly divided into 4 groups based on their gender and body weight: group A (hLf rice high-dose group with 71.45% rice), group B (hLf rice medium-dose group with 35. 725% rice), group C (parental rice group with 71.01% rice) and group D (AIN-93G diet group), and the latter two groups were used as the control. Body weight, dietary intake, blood routine test, blood biochemical examination, organ coefficient, bone density and the pathology of organs were investigated at the end of a 90-day feeding experiment. Except for human lactoferrin and Fe, there was no difference of main nutritional components, minerals and vitamins between groups. The differences of some indicators of blood routine (WBC, HGB, RBC and MCH), blood biochemistry (AST and GLU), organ coefficient and bone density between group A and B (hLf rice) with group C (parental rice) or group D (AIN-93G) were significant, while no difference of other indicators. Although some differences were observed, all indicators were still in the normal reference range. Therefore, there was no sign of toxic and adverse effects for hLf rice on rats.

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

Directory of Open Access Journals (Sweden)

Alex J Bartholomew

Full Text Available 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.

Genetic variations in multiple myeloma I

DEFF Research Database (Denmark)

Vangsted, A.; Klausen, T.W.; Vogel, Ulla Birgitte

2012-01-01

Few risk factors have been established for the plasma cell disorder multiple myeloma, but some of these like African American ethnicity and a family history of B-cell lymphoproliferative diseases suggest a genetic component for the disease. Genetic variation represents the genetic basis of variab......Few risk factors have been established for the plasma cell disorder multiple myeloma, but some of these like African American ethnicity and a family history of B-cell lymphoproliferative diseases suggest a genetic component for the disease. Genetic variation represents the genetic basis...

Application of DNA Hybridization Biosensor as a Screening Method for the Detection of Genetically Modified Food Components

Directory of Open Access Journals (Sweden)

Marian Filipiak

2008-03-01

Full Text Available An electrochemical biosensor for the detection of genetically modified food components is presented. The biosensor was based on 21-mer single-stranded oligonucleotide (ssDNA probe specific to either 35S promoter or nos terminator, which are frequently present in transgenic DNA cassettes. ssDNA probe was covalently attached by 5’-phosphate end to amino group of cysteamine self-assembled monolayer (SAM on gold electrode surface with the use of activating reagents – water soluble 1-ethyl-3(3’- dimethylaminopropyl-carbodiimide (EDC and N-hydroxy-sulfosuccinimide (NHS. The hybridization reaction on the electrode surface was detected via methylene blue (MB presenting higher affinity to ssDNA probe than to DNA duplex. The electrode modification procedure was optimized using 19-mer oligoG and oligoC nucleotides. The biosensor enabled distinction between DNA samples isolated from soybean RoundupReady® (RR soybean and non-genetically modified soybean. The frequent introduction of investigated DNA sequences in other genetically modified organisms (GMOs give a broad perspectives for analytical application of the biosensor.

Clustering of immunological, metabolic and genetic features in latent autoimmune diabetes in adults: evidence from principal component analysis.

Science.gov (United States)

Pes, Giovanni Mario; Delitala, Alessandro Palmerio; Errigo, Alessandra; Delitala, Giuseppe; Dore, Maria Pina

2016-06-01

Latent autoimmune diabetes in adults (LADA) which accounts for more than 10 % of all cases of diabetes is characterized by onset after age 30, absence of ketoacidosis, insulin independence for at least 6 months, and presence of circulating islet-cell antibodies. Its marked heterogeneity in clinical features and immunological markers suggests the existence of multiple mechanisms underlying its pathogenesis. The principal component (PC) analysis is a statistical approach used for finding patterns in data of high dimension. In this study the PC analysis was applied to a set of variables from a cohort of Sardinian LADA patients to identify a smaller number of latent patterns. A list of 11 variables including clinical (gender, BMI, lipid profile, systolic and diastolic blood pressure and insulin-free time period), immunological (anti-GAD65, anti-IA-2 and anti-TPO antibody titers) and genetic features (predisposing gene variants previously identified as risk factors for autoimmune diabetes) retrieved from clinical records of 238 LADA patients referred to the Internal Medicine Unit of University of Sassari, Italy, were analyzed by PC analysis. The predictive value of each PC on the further development of insulin dependence was evaluated using Kaplan-Meier curves. Overall 4 clusters were identified by PC analysis. In component PC-1, the dominant variables were: BMI, triglycerides, systolic and diastolic blood pressure and duration of insulin-free time period; in PC-2: genetic variables such as Class II HLA, CTLA-4 as well as anti-GAD65, anti-IA-2 and anti-TPO antibody titers, and the insulin-free time period predominated; in PC-3: gender and triglycerides; and in PC-4: total cholesterol. These components explained 18, 15, 12, and 12 %, respectively, of the total variance in the LADA cohort. The predictive power of insulin dependence of the four components was different. PC-2 (characterized mostly by high antibody titers and presence of predisposing genetic markers

Analysis of a genetically structured variance heterogeneity model using the Box-Cox transformation.

Science.gov (United States)

Yang, Ye; Christensen, Ole F; Sorensen, Daniel

2011-02-01

Over recent years, statistical support for the presence of genetic factors operating at the level of the environmental variance has come from fitting a genetically structured heterogeneous variance model to field or experimental data in various species. Misleading results may arise due to skewness of the marginal distribution of the data. To investigate how the scale of measurement affects inferences, the genetically structured heterogeneous variance model is extended to accommodate the family of Box-Cox transformations. Litter size data in rabbits and pigs that had previously been analysed in the untransformed scale were reanalysed in a scale equal to the mode of the marginal posterior distribution of the Box-Cox parameter. In the rabbit data, the statistical evidence for a genetic component at the level of the environmental variance is considerably weaker than that resulting from an analysis in the original metric. In the pig data, the statistical evidence is stronger, but the coefficient of correlation between additive genetic effects affecting mean and variance changes sign, compared to the results in the untransformed scale. The study confirms that inferences on variances can be strongly affected by the presence of asymmetry in the distribution of data. We recommend that to avoid one important source of spurious inferences, future work seeking support for a genetic component acting on environmental variation using a parametric approach based on normality assumptions confirms that these are met.

Ionospheric convection response to changes of interplanetary magnetic field B-z component during strong B-y component

DEFF Research Database (Denmark)

Huang, C.S.; Murr, D.; Sofko, G.J.

2000-01-01

response to IMF Bz changes during strong IMF BZ. On March 23, 1995, B-x was small, B-y was strongly positive (7-11 nT), and the B-z polarity changed several times after 1300 UT. The dayside ionospheric convection is dominated by a large clockwise convection cell. The cell focus (the "eye" of the convection...... cell, or the largest change in the convection pattern, is limited roughly to the region between the previous cell focus and the new cell focus. Outside this region, the ionospheric flows could be greatly enhanced or weakened, while the convection pattern shape changes very little. When B-y is strong...... the dawn-dusk meridian plane, which is interpreted as propagation or expansion of newly generated convection cells in the cusp region. Other studies showed that the change in convection pattern in response to IMF reorientations is spatially fixed. In this paper, we investigate the ionospheric convection...

Recent developments in the genetics of schizophrenia.

Science.gov (United States)

Shastry, B S

1999-09-01

Schizophrenia, which is also called "split personality," is a complex and multifactorial mental disorder with variable clinical manifestations. It perhaps represents several diseases and occurs throughout the world. It is a more-prevalent disorder among homeless people and is clinically characterized by hallucinations and delusions. The pathophysiology of schizophrenia is not localized to a single region of the brain and the etiology of this illness is not understood. Because of its complex pattern of inheritance, genetic techniques are not readily applicable in identifying the genes responsible for this disorder. Family, twin, and adoption studies, however, provide strong but indirect support for genetic components in the etiology of schizophrenia. Extensive linkage analyses now suggest that susceptibility genes may be present on chromosomes 5q, 6p, 8p, 13q, 18p, and 22q. Identification and characterization of these and other genes, as well as non-genetic factors, is one of the greatest challenges in biomedicine. This may ultimately lead to the development of a new line of effective and safe drugs or treatments for its prevention or cure.

Strong Decomposition of Random Variables

DEFF Research Database (Denmark)

Hoffmann-Jørgensen, Jørgen; Kagan, Abram M.; Pitt, Loren D.

2007-01-01

A random variable X is stongly decomposable if X=Y+Z where Y=Φ(X) and Z=X-Φ(X) are independent non-degenerated random variables (called the components). It is shown that at least one of the components is singular, and we derive a necessary and sufficient condition for strong decomposability...... of a discrete random variable....

Associated genetic syndromes and extracardiac malformations strongly influence outcomes of fetuses with congenital heart diseases.

Science.gov (United States)

Bensemlali, Myriam; Bajolle, Fanny; Ladouceur, Magalie; Fermont, Laurent; Lévy, Marilyne; Le Bidois, Jérôme; Salomon, Laurent J; Bonnet, Damien

2016-05-01

Congenital heart disease (CHD) is often associated with extracardiac malformations (ECMs) and genetic syndromes. To determine the effect of cytogenetic anomalies and/or ECMs associated with CHD on parental decision to choose termination of pregnancy (TOP) or compassionate care (CC), as well as on the outcome of children born alive. This 10-year retrospective study included all prenatally diagnosed cases of CHD in a single tertiary referral centre. From January 2002 to December 2011, 2036 consecutive cases of fetal CHD (798 TOPs and 1238 live births, including 59 with postnatal CC) were included. CHD was associated with a known cytogenetic anomaly in 9.8% of cases and a major ECM in 11.7% of cases. The proportion of prenatally identified associated cytogenetic anomalies was significantly lower in the live-birth group than in the TOP plus CC group (4.2% vs 17.5%; P<0.001); this was also true for ECMs (8.1% vs 16.7%; P<0.001). The mortality rate was higher in the group with an associated cytogenetic anomaly or ECM (29.1%) than in cases with isolated CHD; a 2.4-fold increase in the death rate was observed (95% confidence interval 1.34-4.38; P=0.003). These associations remained significant after multivariable analysis, including the severity of the CHD (uni- or biventricular physiology). Prenatal diagnosis of a known cytogenetic anomaly or major ECM strongly influences parental decision to choose TOP or postnatal CC. Genetic syndromes and ECMs are associated with a higher mortality rate, independent of the complexity of the CHD. Copyright © 2016 Elsevier Masson SAS. All rights reserved.

Variable-number-of-tandem-repeats analysis of genetic diversity in Pasteuria ramosa.

Science.gov (United States)

Mouton, L; Ebert, D

2008-05-01

Variable-number-of-tandem-repeats (VNTR) markers are increasingly being used in population genetic studies of bacteria. They were recently developed for Pasteuria ramosa, an endobacterium that infects Daphnia species. In the present study, we genotyped P. ramosa in 18 infected hosts from the United Kingdom, Belgium, and two lakes in the United States using seven VNTR markers. Two Daphnia species were collected: D. magna and D. dentifera. Six loci showed length polymorphism, with as many as five alleles identified for a single locus. Similarity coefficient calculations showed that the extent of genetic variation between pairs of isolates within populations differed according to the population, but it was always less than the genetic distances among populations. Analysis of the genetic distances performed using principal component analysis revealed strong clustering by location of origin, but not by host Daphnia species. Our study demonstrated that the VNTR markers available for P. ramosa are informative in revealing genetic differences within and among populations and may therefore become an important tool for providing detailed analysis of population genetics and epidemiology.

Chymotrypsinogen C Genetic Variants, Including c.180TT, Are Strongly Associated With Chronic Pancreatitis in Pediatric Patients.

Science.gov (United States)

Grabarczyk, Alicja Monika; Oracz, Grzegorz; Wertheim-Tysarowska, Katarzyna; Kujko, Aleksandra Anna; Wejnarska, Karolina; Kolodziejczyk, Elwira; Bal, Jerzy; Koziel, Dorota; Kowalik, Artur; Gluszek, Stanislaw; Rygiel, Agnieszka Magdalena

2017-12-01

Genetic studies in adults/adolescent patients with chronic pancreatitis (CP) identified chymotrypsinogen C (CTRC) genetic variants but their association with CP risk has been difficult to replicate. To evaluate the risk of CP associated with CTRC variants in CP pediatric patients-control study. The distribution of CTRC variants in CP pediatric cohort (n = 136, median age at CP onset 8 years) with no history of alcohol/smoking abuse was compared with controls (n = 401, median age 45). We showed that p.Arg254Trp (4.6%) and p.Lys247_Arg254del (5.3%) heterozygous mutations are frequent and significantly associated with CP risk in pediatric patients (odds ratio [OR] = 19.1; 95% CI 2.8-160; P = 0.001 and OR = 5.5; 95% CI 1.6-19.4; P = 0.001, respectively). For the first time, we demonstrated that the c.180TT genotype of common p.Gly60Gly variant is strong, an independent CP risk factor (OR = 23; 95% CI 7.7-70; P A variant, both CA and AA genotype, is significantly underrepresented in CP compared with controls (15% vs 35%; OR = 0.33; 95% CI 0.19-0.59; P risk factors. The c.493+51C>A variant may play a protective role against CP development.

A novel method to design S-box based on chaotic map and genetic algorithm

International Nuclear Information System (INIS)

Wang, Yong; Wong, Kwok-Wo; Li, Changbing; Li, Yang

2012-01-01

The substitution box (S-box) is an important component in block encryption algorithms. In this Letter, the problem of constructing S-box is transformed to a Traveling Salesman Problem and a method for designing S-box based on chaos and genetic algorithm is proposed. Since the proposed method makes full use of the traits of chaotic map and evolution process, stronger S-box is obtained. The results of performance test show that the presented S-box has good cryptographic properties, which justify that the proposed algorithm is effective in generating strong S-boxes. -- Highlights: ► The problem of constructing S-box is transformed to a Traveling Salesman Problem. ► We present a new method for designing S-box based on chaos and genetic algorithm. ► The proposed algorithm is effective in generating strong S-boxes.

A novel method to design S-box based on chaotic map and genetic algorithm

Energy Technology Data Exchange (ETDEWEB)

Wang, Yong, E-mail: wangyong_cqupt@163.com [State Key Laboratory of Power Transmission Equipment and System Security and New Technology, Chongqing University, Chongqing 400044 (China); Key Laboratory of Electronic Commerce and Logistics, Chongqing University of Posts and Telecommunications, Chongqing 400065 (China); Wong, Kwok-Wo [Department of Electronic Engineering, City University of Hong Kong, 83 Tat Chee Avenue, Kowloon Tong (Hong Kong); Li, Changbing [Key Laboratory of Electronic Commerce and Logistics, Chongqing University of Posts and Telecommunications, Chongqing 400065 (China); Li, Yang [Department of Automatic Control and Systems Engineering, The University of Sheffield, Mapping Street, S1 3DJ (United Kingdom)

2012-01-30

The substitution box (S-box) is an important component in block encryption algorithms. In this Letter, the problem of constructing S-box is transformed to a Traveling Salesman Problem and a method for designing S-box based on chaos and genetic algorithm is proposed. Since the proposed method makes full use of the traits of chaotic map and evolution process, stronger S-box is obtained. The results of performance test show that the presented S-box has good cryptographic properties, which justify that the proposed algorithm is effective in generating strong S-boxes. -- Highlights: ► The problem of constructing S-box is transformed to a Traveling Salesman Problem. ► We present a new method for designing S-box based on chaos and genetic algorithm. ► The proposed algorithm is effective in generating strong S-boxes.

Genetic Interactions Between the Meiosis-Specific Cohesin Components, STAG3, REC8, and RAD21L.

Science.gov (United States)

Ward, Ayobami; Hopkins, Jessica; Mckay, Matthew; Murray, Steve; Jordan, Philip W

2016-06-01

Cohesin is an essential structural component of chromosomes that ensures accurate chromosome segregation during mitosis and meiosis. Previous studies have shown that there are cohesin complexes specific to meiosis, required to mediate homologous chromosome pairing, synapsis, recombination, and segregation. Meiosis-specific cohesin complexes consist of two structural maintenance of chromosomes proteins (SMC1α/SMC1β and SMC3), an α-kleisin protein (RAD21, RAD21L, or REC8), and a stromal antigen protein (STAG1, 2, or 3). STAG3 is exclusively expressed during meiosis, and is the predominant STAG protein component of cohesin complexes in primary spermatocytes from mouse, interacting directly with each α-kleisin subunit. REC8 and RAD21L are also meiosis-specific cohesin components. Stag3 mutant spermatocytes arrest in early prophase ("zygotene-like" stage), displaying failed homolog synapsis and persistent DNA damage, as a result of unstable loading of cohesin onto the chromosome axes. Interestingly, Rec8, Rad21L double mutants resulted in an earlier "leptotene-like" arrest, accompanied by complete absence of STAG3 loading. To assess genetic interactions between STAG3 and α-kleisin subunits RAD21L and REC8, our lab generated Stag3, Rad21L, and Stag3, Rec8 double knockout mice, and compared them to the Rec8, Rad21L double mutant. These double mutants are phenotypically distinct from one another, and more severe than each single knockout mutant with regards to chromosome axis formation, cohesin loading, and sister chromatid cohesion. The Stag3, Rad21L, and Stag3, Rec8 double mutants both progress further into prophase I than the Rec8, Rad21L double mutant. Our genetic analysis demonstrates that cohesins containing STAG3 and REC8 are the main complex required for centromeric cohesion, and RAD21L cohesins are required for normal clustering of pericentromeric heterochromatin. Furthermore, the STAG3/REC8 and STAG3/RAD21L cohesins are the primary cohesins required for

Genetic algorithm using independent component analysis in x-ray reflectivity curve fitting of periodic layer structures

International Nuclear Information System (INIS)

Tiilikainen, J; Bosund, V; Tilli, J-M; Sormunen, J; Mattila, M; Hakkarainen, T; Lipsanen, H

2007-01-01

A novel genetic algorithm (GA) utilizing independent component analysis (ICA) was developed for x-ray reflectivity (XRR) curve fitting. EFICA was used to reduce mutual information, or interparameter dependences, during the combinatorial phase. The performance of the new algorithm was studied by fitting trial XRR curves to target curves which were computed using realistic multilayer models. The median convergence properties of conventional GA, GA using principal component analysis and the novel GA were compared. GA using ICA was found to outperform the other methods with problems having 41 parameters or more to be fitted without additional XRR curve calculations. The computational complexity of the conventional methods was linear but the novel method had a quadratic computational complexity due to the applied ICA method which sets a practical limit for the dimensionality of the problem to be solved. However, the novel algorithm had the best capability to extend the fitting analysis based on Parratt's formalism to multiperiodic layer structures

Genome-wide association study identified genetic variations and candidate genes for plant architecture component traits in Chinese upland cotton.

Science.gov (United States)

Su, Junji; Li, Libei; Zhang, Chi; Wang, Caixiang; Gu, Lijiao; Wang, Hantao; Wei, Hengling; Liu, Qibao; Huang, Long; Yu, Shuxun

2018-06-01

Thirty significant associations between 22 SNPs and five plant architecture component traits in Chinese upland cotton were identified via GWAS. Four peak SNP loci located on chromosome D03 were simultaneously associated with more plant architecture component traits. A candidate gene, Gh_D03G0922, might be responsible for plant height in upland cotton. A compact plant architecture is increasingly required for mechanized harvesting processes in China. Therefore, cotton plant architecture is an important trait, and its components, such as plant height, fruit branch length and fruit branch angle, affect the suitability of a cultivar for mechanized harvesting. To determine the genetic basis of cotton plant architecture, a genome-wide association study (GWAS) was performed using a panel composed of 355 accessions and 93,250 single nucleotide polymorphisms (SNPs) identified using the specific-locus amplified fragment sequencing method. Thirty significant associations between 22 SNPs and five plant architecture component traits were identified via GWAS. Most importantly, four peak SNP loci located on chromosome D03 were simultaneously associated with more plant architecture component traits, and these SNPs were harbored in one linkage disequilibrium block. Furthermore, 21 candidate genes for plant architecture were predicted in a 0.95-Mb region including the four peak SNPs. One of these genes (Gh_D03G0922) was near the significant SNP D03_31584163 (8.40 kb), and its Arabidopsis homologs contain MADS-box domains that might be involved in plant growth and development. qRT-PCR showed that the expression of Gh_D03G0922 was upregulated in the apical buds and young leaves of the short and compact cotton varieties, and virus-induced gene silencing (VIGS) proved that the silenced plants exhibited increased PH. These results indicate that Gh_D03G0922 is likely the candidate gene for PH in cotton. The genetic variations and candidate genes identified in this study lay a foundation

Genetic evolution, plasticity, and bet-hedging as adaptive responses to temporally autocorrelated fluctuating selection: A quantitative genetic model.

Science.gov (United States)

Tufto, Jarle

2015-08-01

Adaptive responses to autocorrelated environmental fluctuations through evolution in mean reaction norm elevation and slope and an independent component of the phenotypic variance are analyzed using a quantitative genetic model. Analytic approximations expressing the mutual dependencies between all three response modes are derived and solved for the joint evolutionary outcome. Both genetic evolution in reaction norm elevation and plasticity are favored by slow temporal fluctuations, with plasticity, in the absence of microenvironmental variability, being the dominant evolutionary outcome for reasonable parameter values. For fast fluctuations, tracking of the optimal phenotype through genetic evolution and plasticity is limited. If residual fluctuations in the optimal phenotype are large and stabilizing selection is strong, selection then acts to increase the phenotypic variance (bet-hedging adaptive). Otherwise, canalizing selection occurs. If the phenotypic variance increases with plasticity through the effect of microenvironmental variability, this shifts the joint evolutionary balance away from plasticity in favor of genetic evolution. If microenvironmental deviations experienced by each individual at the time of development and selection are correlated, however, more plasticity evolves. The adaptive significance of evolutionary fluctuations in plasticity and the phenotypic variance, transient evolution, and the validity of the analytic approximations are investigated using simulations. © 2015 The Author(s). Evolution © 2015 The Society for the Study of Evolution.

Genetic factors in exercise adoption, adherence and obesity.

Science.gov (United States)

Herring, M P; Sailors, M H; Bray, M S

2014-01-01

Physical activity and exercise play critical roles in energy balance. While many interventions targeted at increasing physical activity have demonstrated efficacy in promoting weight loss or maintenance in the short term, long term adherence to such programmes is not frequently observed. Numerous factors have been examined for their ability to predict and/or influence physical activity and exercise adherence. Although physical activity has been demonstrated to have a strong genetic component in both animals and humans, few studies have examined the association between genetic variation and exercise adherence. In this review, we provide a detailed overview of the non-genetic and genetic predictors of physical activity and adherence to exercise. In addition, we report the results of analysis of 26 single nucleotide polymorphisms in six candidate genes examined for association to exercise adherence, duration, intensity and total exercise dose in young adults from the Training Interventions and Genetics of Exercise Response (TIGER) Study. Based on both animal and human research, neural signalling and pleasure/reward systems in the brain may drive in large part the propensity to be physically active and to adhere to an exercise programme. Adherence/compliance research in other fields may inform future investigation of the genetics of exercise adherence. © 2013 The Authors. obesity reviews © 2013 International Association for the Study of Obesity.

Modular and coordinated expression of immune system regulatory and signaling components in the developing and adult nervous system.

Science.gov (United States)

Monzón-Sandoval, Jimena; Castillo-Morales, Atahualpa; Crampton, Sean; McKelvey, Laura; Nolan, Aoife; O'Keeffe, Gerard; Gutierrez, Humberto

2015-01-01

During development, the nervous system (NS) is assembled and sculpted through a concerted series of neurodevelopmental events orchestrated by a complex genetic programme. While neural-specific gene expression plays a critical part in this process, in recent years, a number of immune-related signaling and regulatory components have also been shown to play key physiological roles in the developing and adult NS. While the involvement of individual immune-related signaling components in neural functions may reflect their ubiquitous character, it may also reflect a much wider, as yet undescribed, genetic network of immune-related molecules acting as an intrinsic component of the neural-specific regulatory machinery that ultimately shapes the NS. In order to gain insights into the scale and wider functional organization of immune-related genetic networks in the NS, we examined the large scale pattern of expression of these genes in the brain. Our results show a highly significant correlated expression and transcriptional clustering among immune-related genes in the developing and adult brain, and this correlation was the highest in the brain when compared to muscle, liver, kidney and endothelial cells. We experimentally tested the regulatory clustering of immune system (IS) genes by using microarray expression profiling in cultures of dissociated neurons stimulated with the pro-inflammatory cytokine TNF-alpha, and found a highly significant enrichment of immune system-related genes among the resulting differentially expressed genes. Our findings strongly suggest a coherent recruitment of entire immune-related genetic regulatory modules by the neural-specific genetic programme that shapes the NS.

A Strong Case for Viral Genetic Factors in HIV Virulence

Directory of Open Access Journals (Sweden)

Joshua T. Herbeck

2011-03-01

Full Text Available HIV infections show great variation in the rate of progression to disease, and the role of viral genetic factors in this variation had remained poorly characterized until recently. Now a series of four studies [1–4] published within a year has filled this important gap and has demonstrated a robust effect of the viral genotype on HIV virulence.

Genetic determination of mortality rate in Danish dairy cows

DEFF Research Database (Denmark)

Maia, Rafael Pimentel; Ask, Birgitte; Madsen, Per

2014-01-01

: a sire random component with pedigree representing the sire genetic effects and a herd-year-season component. Moreover, the level of heterozygosity and the sire breed proportions were included in the models as covariates in order to account for potential non-additive genetic effects due to the massive...... introduction of genetic material from other populations. The correlations between the sire components for death rate and slaughter rate were negative and small for the 3 populations, suggesting the existence of specific genetic mechanisms for each culling reason and common concurrent genetic mechanisms...

The genetic architecture of fitness in a seed beetle: assessing the potential for indirect genetic benefits of female choice

Directory of Open Access Journals (Sweden)

Maklakov AA

2008-10-01

Full Text Available Abstract Background Quantifying the amount of standing genetic variation in fitness represents an empirical challenge. Unfortunately, the shortage of detailed studies of the genetic architecture of fitness has hampered progress in several domains of evolutionary biology. One such area is the study of sexual selection. In particular, the evolution of adaptive female choice by indirect genetic benefits relies on the presence of genetic variation for fitness. Female choice by genetic benefits fall broadly into good genes (additive models and compatibility (non-additive models where the strength of selection is dictated by the genetic architecture of fitness. To characterize the genetic architecture of fitness, we employed a quantitative genetic design (the diallel cross in a population of the seed beetle Callosobruchus maculatus, which is known to exhibit post-copulatory female choice. From reciprocal crosses of inbred lines, we assayed egg production, egg-to-adult survival, and lifetime offspring production of the outbred F1 daughters (F1 productivity. Results We used the bio model to estimate six components of genetic and environmental variance in fitness. We found sizeable additive and non-additive genetic variance in F1 productivity, but lower genetic variance in egg-to-adult survival, which was strongly influenced by maternal and paternal effects. Conclusion Our results show that, in order to gain a relevant understanding of the genetic architecture of fitness, measures of offspring fitness should be inclusive and should include quantifications of offspring reproductive success. We note that our estimate of additive genetic variance in F1 productivity (CVA = 14% is sufficient to generate indirect selection on female choice. However, our results also show that the major determinant of offspring fitness is the genetic interaction between parental genomes, as indicated by large amounts of non-additive genetic variance (dominance and/or epistasis

Individual Differences in the Speed of Facial Emotion Recognition Show Little Specificity but Are Strongly Related with General Mental Speed: Psychometric, Neural and Genetic Evidence

Directory of Open Access Journals (Sweden)

Xinyang Liu

2017-08-01

Full Text Available Facial identity and facial expression processing are crucial socio-emotional abilities but seem to show only limited psychometric uniqueness when the processing speed is considered in easy tasks. We applied a comprehensive measurement of processing speed and contrasted performance specificity in socio-emotional, social and non-social stimuli from an individual differences perspective. Performance in a multivariate task battery could be best modeled by a general speed factor and a first-order factor capturing some specific variance due to processing emotional facial expressions. We further tested equivalence of the relationships between speed factors and polymorphisms of dopamine and serotonin transporter genes. Results show that the speed factors are not only psychometrically equivalent but invariant in their relation with the Catechol-O-Methyl-Transferase (COMT Val158Met polymorphism. However, the 5-HTTLPR/rs25531 serotonin polymorphism was related with the first-order factor of emotion perception speed, suggesting a specific genetic correlate of processing emotions. We further investigated the relationship between several components of event-related brain potentials with psychometric abilities, and tested emotion specific individual differences at the neurophysiological level. Results revealed swifter emotion perception abilities to go along with larger amplitudes of the P100 and the Early Posterior Negativity (EPN, when emotion processing was modeled on its own. However, after partialling out the shared variance of emotion perception speed with general processing speed-related abilities, brain-behavior relationships did not remain specific for emotion. Together, the present results suggest that speed abilities are strongly interrelated but show some specificity for emotion processing speed at the psychometric level. At both genetic and neurophysiological levels, emotion specificity depended on whether general cognition is taken into account

Individual Differences in the Speed of Facial Emotion Recognition Show Little Specificity but Are Strongly Related with General Mental Speed: Psychometric, Neural and Genetic Evidence

Science.gov (United States)

Liu, Xinyang; Hildebrandt, Andrea; Recio, Guillermo; Sommer, Werner; Cai, Xinxia; Wilhelm, Oliver

2017-01-01

Facial identity and facial expression processing are crucial socio-emotional abilities but seem to show only limited psychometric uniqueness when the processing speed is considered in easy tasks. We applied a comprehensive measurement of processing speed and contrasted performance specificity in socio-emotional, social and non-social stimuli from an individual differences perspective. Performance in a multivariate task battery could be best modeled by a general speed factor and a first-order factor capturing some specific variance due to processing emotional facial expressions. We further tested equivalence of the relationships between speed factors and polymorphisms of dopamine and serotonin transporter genes. Results show that the speed factors are not only psychometrically equivalent but invariant in their relation with the Catechol-O-Methyl-Transferase (COMT) Val158Met polymorphism. However, the 5-HTTLPR/rs25531 serotonin polymorphism was related with the first-order factor of emotion perception speed, suggesting a specific genetic correlate of processing emotions. We further investigated the relationship between several components of event-related brain potentials with psychometric abilities, and tested emotion specific individual differences at the neurophysiological level. Results revealed swifter emotion perception abilities to go along with larger amplitudes of the P100 and the Early Posterior Negativity (EPN), when emotion processing was modeled on its own. However, after partialling out the shared variance of emotion perception speed with general processing speed-related abilities, brain-behavior relationships did not remain specific for emotion. Together, the present results suggest that speed abilities are strongly interrelated but show some specificity for emotion processing speed at the psychometric level. At both genetic and neurophysiological levels, emotion specificity depended on whether general cognition is taken into account or not. These

Human genetics as a tool to identify progranulin regulators.

Science.gov (United States)

Nicholson, Alexandra M; Finch, NiCole A; Rademakers, Rosa

2011-11-01

Frontotemporal lobar degeneration (FTLD) is a common neurodegenerative disorder that predominantly affects individuals under the age of 65. It is known that the most common pathological subtype is FTLD with TAR DNA-binding protein 43 inclusions (FTLD-TDP). FTLD has a strong genetic component with about 50% of cases having a positive family history. Mutations identified in the progranulin gene (GRN) have been shown to cause FTLD-TDP as a result of progranulin haploinsufficiency. These findings suggest a progranulin-dependent mechanism in this pathological FTLD subtype. Thus, identifying regulators of progranulin levels is essential for new therapies and treatments for FTLD and related disorders. In this review, we discuss the role of genetic studies in identifying progranulin regulators, beginning with the discovery of pathogenic GRN mutations and additional GRN risk variants. We also cover more recent genetic advances, including the detection of variants in the transmembrane protein 106 B gene that increase FTLD-TDP risk presumably by modulating progranulin levels and the identification of a potential progranulin receptor, sortilin. This review highlights the importance of genetic studies in the context of FTLD and further emphasizes the need for future genetic and cell biology research to continue the effort in finding a cure for progranulin-related diseases.

Chemosensory responsiveness to ethanol and its individual sensory components in alcohol-preferring, -nonpreferring and genetically heterogeneous rats

Science.gov (United States)

Brasser, Susan M.; Silbaugh, Bryant C.; Ketchum, Myles J.; Olney, Jeffrey J.; Lemon, Christian H.

2011-01-01

Alcohol activates orosensory circuits that project to motivationally relevant limbic forebrain areas that control appetite, feeding and drinking. To date, limited data exists regarding the contribution of chemosensory-derived ethanol reinforcement to ethanol preference and consumption. Measures of taste reactivity to intra-orally infused ethanol have not found differences in initial orofacial responses to alcohol between alcohol-preferring (P) and – nonpreferring (NP) genetically selected rat lines. Yet, in voluntary intake tests P rats prefer highly-concentrated ethanol upon initial exposure, suggesting an early sensory-mediated attraction. Here, we directly compared self-initiated chemosensory responding for alcohol and prototypic sweet, bitter, and oral trigeminal stimuli among selectively bred P, NP, and non-selected Wistar (WI) outbred lines to determine whether differential sensory responsiveness to ethanol and its putative sensory components are phenotypically associated with genetically-influenced alcohol preference. Rats were tested for immediate short-term lick responses to alcohol (3–40%), sucrose (0.01–1 M), quinine (0.01–3 mM) and capsaicin (0.003–1 mM) in a brief-access assay designed to index orosensory-guided behavior. P rats exhibited elevated short-term lick responses to both alcohol and sucrose relative to NP and WI lines across a broad range of concentrations of each stimulus and in the absence of blood alcohol levels that would produce significant postabsorptive effects. There was no consistent relationship between genetically-mediated alcohol preference and orosensory avoidance of quinine or capsaicin. These data indicate that enhanced initial chemosensory attraction to ethanol and sweet stimuli are phenotypes associated with genetic alcohol preference and are considered within the framework of downstream activation of oral appetitive reward circuits. PMID:22129513

'Faceness' and affectivity: evidence for genetic contributions to distinct components of electrocortical response to human faces.

Science.gov (United States)

Shannon, Robert W; Patrick, Christopher J; Venables, Noah C; He, Sheng

2013-12-01

The ability to recognize a variety of different human faces is undoubtedly one of the most important and impressive functions of the human perceptual system. Neuroimaging studies have revealed multiple brain regions (including the FFA, STS, OFA) and electrophysiological studies have identified differing brain event-related potential (ERP) components (e.g., N170, P200) possibly related to distinct types of face information processing. To evaluate the heritability of ERP components associated with face processing, including N170, P200, and LPP, we examined ERP responses to fearful and neutral face stimuli in monozygotic (MZ) and dizygotic (DZ) twins. Concordance levels for early brain response indices of face processing (N170, P200) were found to be stronger for MZ than DZ twins, providing evidence of a heritable basis to each. These findings support the idea that certain key neural mechanisms for face processing are genetically coded. Implications for understanding individual differences in recognition of facial identity and the emotional content of faces are discussed. Copyright © 2013 Elsevier Inc. All rights reserved.

Genetic parameters and expected responses to selection for components of feed efficiency in a Duroc pig line.

Science.gov (United States)

Sánchez, Juan P; Ragab, Mohamed; Quintanilla, Raquel; Rothschild, Max F; Piles, Miriam

2017-12-01

Improving feed efficiency ([Formula: see text]) is a key factor for any pig breeding company. Although this can be achieved by selection on an index of multi-trait best linear unbiased prediction of breeding values with optimal economic weights, considering deviations of feed intake from actual needs ([Formula: see text]) should be of value for further research on biological aspects of [Formula: see text]. Here, we present a random regression model that extends the classical definition of [Formula: see text] by including animal-specific needs in the model. Using this model, we explore the genetic determinism of several [Formula: see text] components: use of feed for growth ([Formula: see text]), use of feed for backfat deposition ([Formula: see text]), use of feed for maintenance ([Formula: see text]), and unspecific efficiency in the use of feed ([Formula: see text]). Expected response to alternative selection indexes involving different components is also studied. Based on goodness-of-fit to the available feed intake ([Formula: see text]) data, the model that assumes individual (genetic and permanent) variation in the use of feed for maintenance, [Formula: see text] and [Formula: see text] showed the best performance. Joint individual variation in feed allocation to maintenance, growth and backfat deposition comprised 37% of the individual variation of [Formula: see text]. The estimated heritabilities of [Formula: see text] using the model that accounts for animal-specific needs and the traditional [Formula: see text] model were 0.12 and 0.18, respectively. The estimated heritabilities for the regression coefficients were 0.44, 0.39 and 0.55 for [Formula: see text], [Formula: see text] and [Formula: see text], respectively. Estimates of genetic correlations of [Formula: see text] were positive with amount of feed used for [Formula: see text] and [Formula: see text] but negative for [Formula: see text]. Expected response in overall efficiency, reducing [Formula

The Tourette International Collaborative Genetics (TIC Genetics) study, finding the genes causing Tourette syndrome

DEFF Research Database (Denmark)

Dietrich, Andrea; Fernandez, Thomas V; King, Robert A

2015-01-01

Tourette syndrome (TS) is a neuropsychiatric disorder characterized by recurrent motor and vocal tics, often accompanied by obsessive-compulsive disorder and/or attention-deficit/hyperactivity disorder. While the evidence for a genetic contribution is strong, its exact nature has yet to be clarif......Tourette syndrome (TS) is a neuropsychiatric disorder characterized by recurrent motor and vocal tics, often accompanied by obsessive-compulsive disorder and/or attention-deficit/hyperactivity disorder. While the evidence for a genetic contribution is strong, its exact nature has yet......, it is clear that large patient cohorts and open-access repositories will be essential to further advance the field. To that end, the large multicenter Tourette International Collaborative Genetics (TIC Genetics) study was established. The goal of the TIC Genetics study is to undertake a comprehensive gene...... discovery effort, focusing both on familial genetic variants with large effects within multiply affected pedigrees and on de novo mutations ascertained through the analysis of apparently simplex parent-child trios with non-familial tics. The clinical data and biomaterials (DNA, transformed cell lines, RNA...

Analysis of a genetically structured variance heterogeneity model using the Box-Cox transformation

DEFF Research Database (Denmark)

Yang, Ye; Christensen, Ole Fredslund; Sorensen, Daniel

2011-01-01

of the marginal distribution of the data. To investigate how the scale of measurement affects inferences, the genetically structured heterogeneous variance model is extended to accommodate the family of Box–Cox transformations. Litter size data in rabbits and pigs that had previously been analysed...... in the untransformed scale were reanalysed in a scale equal to the mode of the marginal posterior distribution of the Box–Cox parameter. In the rabbit data, the statistical evidence for a genetic component at the level of the environmental variance is considerably weaker than that resulting from an analysis...... in the original metric. In the pig data, the statistical evidence is stronger, but the coefficient of correlation between additive genetic effects affecting mean and variance changes sign, compared to the results in the untransformed scale. The study confirms that inferences on variances can be strongly affected...

Quantitative Genetic Analysis for Yield and Yield Components in Boro Rice (Oryza sativa L.

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Supriyo CHAKRABORTY

2010-03-01

Full Text Available Twenty-nine genotypes of boro rice (Oryza sativa L. were grown in a randomized block design with three replications in plots of 4m x 1m with a crop geometry of 20 cm x 20 cm between November-April, in Regional Agricultural Research Station, Nagaon, India. Quantitative data were collected on five randomly selected plants of each genotype per replication for yield/plant, and six other yield components, namely plant height, panicles/plant, panicle length, effective grains/panicle, 100 grain weight and harvest index. Mean values of the characters for each genotype were used for analysis of variance and covariance to obtain information on genotypic and phenotypic correlation along with coheritability between two characters. Path analyses were carried out to estimate the direct and indirect effects of boro rice�s yield components. The objective of the study was to identify the characters that mostly influence the yield for increasing boro rice productivity through breeding program. Correlation analysis revealed significant positive genotypic correlation of yield/plant with plant height (0.21, panicles/plant (0.53, panicle length (0.53, effective grains/panicle (0.57 and harvest index (0.86. Path analysis based on genotypic correlation coefficients elucidated high positive direct effect of harvest index (0.8631, panicle length (0.2560 and 100 grain weight (0.1632 on yield/plant with a residual effect of 0.33. Plant height and panicles/plant recorded high positive indirect effect on yield/plant via harvest index whereas effective grains/panicle on yield/plant via harvest index and panicle length. Results of the present study suggested that five component characters, namely harvest index, effective grains/plant, panicle length, panicles/plant and plant height influenced the yield of boro rice. A genotype with higher magnitude of these component characters could be either selected from the existing genotypes or evolved by breeding program for genetic

Modeling of genetic algorithms with a finite population

NARCIS (Netherlands)

C.H.M. van Kemenade

1997-01-01

textabstractCross-competition between non-overlapping building blocks can strongly influence the performance of evolutionary algorithms. The choice of the selection scheme can have a strong influence on the performance of a genetic algorithm. This paper describes a number of different genetic

A Powerful Approach to Estimating Annotation-Stratified Genetic Covariance via GWAS Summary Statistics.

Science.gov (United States)

Lu, Qiongshi; Li, Boyang; Ou, Derek; Erlendsdottir, Margret; Powles, Ryan L; Jiang, Tony; Hu, Yiming; Chang, David; Jin, Chentian; Dai, Wei; He, Qidu; Liu, Zefeng; Mukherjee, Shubhabrata; Crane, Paul K; Zhao, Hongyu

2017-12-07

Despite the success of large-scale genome-wide association studies (GWASs) on complex traits, our understanding of their genetic architecture is far from complete. Jointly modeling multiple traits' genetic profiles has provided insights into the shared genetic basis of many complex traits. However, large-scale inference sets a high bar for both statistical power and biological interpretability. Here we introduce a principled framework to estimate annotation-stratified genetic covariance between traits using GWAS summary statistics. Through theoretical and numerical analyses, we demonstrate that our method provides accurate covariance estimates, thereby enabling researchers to dissect both the shared and distinct genetic architecture across traits to better understand their etiologies. Among 50 complex traits with publicly accessible GWAS summary statistics (N total ≈ 4.5 million), we identified more than 170 pairs with statistically significant genetic covariance. In particular, we found strong genetic covariance between late-onset Alzheimer disease (LOAD) and amyotrophic lateral sclerosis (ALS), two major neurodegenerative diseases, in single-nucleotide polymorphisms (SNPs) with high minor allele frequencies and in SNPs located in the predicted functional genome. Joint analysis of LOAD, ALS, and other traits highlights LOAD's correlation with cognitive traits and hints at an autoimmune component for ALS. Copyright © 2017 American Society of Human Genetics. Published by Elsevier Inc. All rights reserved.

Multi-Trait analysis of growth traits: fitting reduced rank models using principal components for Simmental beef cattle

Directory of Open Access Journals (Sweden)

Rodrigo Reis Mota

2016-09-01

Full Text Available ABSTRACT: The aim of this research was to evaluate the dimensional reduction of additive direct genetic covariance matrices in genetic evaluations of growth traits (range 100-730 days in Simmental cattle using principal components, as well as to estimate (covariance components and genetic parameters. Principal component analyses were conducted for five different models-one full and four reduced-rank models. Models were compared using Akaike information (AIC and Bayesian information (BIC criteria. Variance components and genetic parameters were estimated by restricted maximum likelihood (REML. The AIC and BIC values were similar among models. This indicated that parsimonious models could be used in genetic evaluations in Simmental cattle. The first principal component explained more than 96% of total variance in both models. Heritability estimates were higher for advanced ages and varied from 0.05 (100 days to 0.30 (730 days. Genetic correlation estimates were similar in both models regardless of magnitude and number of principal components. The first principal component was sufficient to explain almost all genetic variance. Furthermore, genetic parameter similarities and lower computational requirements allowed for parsimonious models in genetic evaluations of growth traits in Simmental cattle.

Molecular basis for genetic deficiency of the second component of human complement

International Nuclear Information System (INIS)

Cole, F.S.; Whitehead, A.S.; Auerbach, H.S.; Lint, T.; Zeitz, H.J.; Kilbridge, P.; Colten, H.R.

1985-01-01

Genetic deficiency of the second component of complement (C2) is the most common complement-deficiency state among Western Europeans and is frequently associated with autoimmune diseases. To examine the molecular basis of this deficiency, the authors established cultures of blood monocytes from four families with C2-deficient members. Using a hemolytic-plaque assay, [ 35 S]methionine metabolic labeling of proteins in tissue culture and immunoprecipitation, RNA extraction and Northern blot analysis, and DNA restriction-enzyme digestion and Southern blot analysis, the authors found that C2 deficiency is not due to a major gene deletion or rearrangement but is the result of a specific and selective pretranslational regulatory defect in C2 gene expression. This leads to a lack of detectable C2 mRNA and a lack of synthesis of C2 protein. The approach used in this study should prove useful in examination of other plasma protein deficiencies, especially those in which the deficient gene is normally expressed in peripheral-blood monocytes or tissue macrophages and in which ethical considerations preclude the use of liver or other tissue for study

Disentangling the intertwined genetic bases of root and shoot growth in Arabidopsis.

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Marie Bouteillé

Full Text Available Root growth and architecture are major components of plant nutrient and water use efficiencies and these traits are the matter of extensive genetic analysis in several crop species. Because root growth relies on exported assimilate from the shoot, and changes in assimilate supply are known to alter root architecture, we hypothesized (i that the genetic bases of root growth could be intertwined with the genetic bases of shoot growth and (ii that the link could be either positive, with alleles favouring shoot growth also favouring root growth, or negative, because of competition for assimilates. We tested these hypotheses using a quantitative genetics approach in the model species Arabidopsis thaliana and the Bay-0 × Shahdara recombinant inbred lines population. In accordance with our hypothesis, root and shoot growth traits were strongly correlated and most root growth quantitative trait loci (QTLs colocalized with shoot growth QTLs with positive alleles originating from either the same or the opposite parent. In order to identify regions that could be responsible for root growth independently of the shoot, we generated new variables either based on root to shoot ratios, residuals of root to shoot correlations or coordinates of principal component analysis. These variables showed high heritability allowing genetic analysis. They essentially all yielded similar results pointing towards two regions involved in the root--shoot balance. Using Heterogeneous Inbred Families (a kind of near-isogenic lines, we validated part of the QTLs present in these two regions for different traits. Our study thus highlights the difficulty of disentangling intertwined genetic bases of root and shoot growth and shows that this difficulty can be overcome by using simple statistical tools.

A Strong Impact of Genetic Background on Gut Microflora in Mice

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R. Steven Esworthy

2010-01-01

Full Text Available Genetic background affects susceptibility to ileocolitis in mice deficient in two intracellular glutathione peroxidases, GPx1 and GPx2. The C57BL/6 (B6 GPx1/2 double-knockout (DKO mice have mild ileocolitis, and 129S1/Sv (129 DKO mice have severe inflammation. We used diet to modulate ileocolitis; a casein-based defined diet with AIN76A micronutrients (AIN attenuates inflammation compared to conventional LabDiets. Because luminal microbiota induce DKO ileocolitis, we assessed bacterial composition with automated ribosomal intergenic-spacer analysis (ARISA on cecal DNA. We found that mouse strain had the strongest impact on the composition of microbiota than diet and GPx genotypes. In comparing AIN and LabDiet, DKO mice were more resistant to change than the non-DKO or WT mice. However, supplementing yeast and inulin to AIN diet greatly altered microflora profiles in the DKO mice. From 129 DKO strictly, we found overgrowth of Escherichia coli. We conclude that genetic background predisposes mice to colonization of potentially pathogenic E. coli.

Genetic Allee effects and their interaction with ecological Allee effects.

Science.gov (United States)

Wittmann, Meike J; Stuis, Hanna; Metzler, Dirk

2018-01-01

It is now widely accepted that genetic processes such as inbreeding depression and loss of genetic variation can increase the extinction risk of small populations. However, it is generally unclear whether extinction risk from genetic causes gradually increases with decreasing population size or whether there is a sharp transition around a specific threshold population size. In the ecological literature, such threshold phenomena are called 'strong Allee effects' and they can arise for example from mate limitation in small populations. In this study, we aim to (i) develop a meaningful notion of a 'strong genetic Allee effect', (ii) explore whether and under what conditions such an effect can arise from inbreeding depression due to recessive deleterious mutations, and (iii) quantify the interaction of potential genetic Allee effects with the well-known mate-finding Allee effect. We define a strong genetic Allee effect as a genetic process that causes a population's survival probability to be a sigmoid function of its initial size. The inflection point of this function defines the critical population size. To characterize survival-probability curves, we develop and analyse simple stochastic models for the ecology and genetics of small populations. Our results indicate that inbreeding depression can indeed cause a strong genetic Allee effect, but only if individuals carry sufficiently many deleterious mutations (lethal equivalents). Populations suffering from a genetic Allee effect often first grow, then decline as inbreeding depression sets in and then potentially recover as deleterious mutations are purged. Critical population sizes of ecological and genetic Allee effects appear to be often additive, but even superadditive interactions are possible. Many published estimates for the number of lethal equivalents in birds and mammals fall in the parameter range where strong genetic Allee effects are expected. Unfortunately, extinction risk due to genetic Allee effects

A general population genetic framework for antagonistic selection that accounts for demography and recurrent mutation.

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Connallon, Tim; Clark, Andrew G

2012-04-01

Antagonistic selection--where alleles at a locus have opposing effects on male and female fitness ("sexual antagonism") or between components of fitness ("antagonistic pleiotropy")--might play an important role in maintaining population genetic variation and in driving phylogenetic and genomic patterns of sexual dimorphism and life-history evolution. While prior theory has thoroughly characterized the conditions necessary for antagonistic balancing selection to operate, we currently know little about the evolutionary interactions between antagonistic selection, recurrent mutation, and genetic drift, which should collectively shape empirical patterns of genetic variation. To fill this void, we developed and analyzed a series of population genetic models that simultaneously incorporate these processes. Our models identify two general properties of antagonistically selected loci. First, antagonistic selection inflates heterozygosity and fitness variance across a broad parameter range--a result that applies to alleles maintained by balancing selection and by recurrent mutation. Second, effective population size and genetic drift profoundly affect the statistical frequency distributions of antagonistically selected alleles. The "efficacy" of antagonistic selection (i.e., its tendency to dominate over genetic drift) is extremely weak relative to classical models, such as directional selection and overdominance. Alleles meeting traditional criteria for strong selection (N(e)s > 1, where N(e) is the effective population size, and s is a selection coefficient for a given sex or fitness component) may nevertheless evolve as if neutral. The effects of mutation and demography may generate population differences in overall levels of antagonistic fitness variation, as well as molecular population genetic signatures of balancing selection.

THE INFLUENCE OF GENETIC VARIANTS OF κ-CASEIN ON MILK COMPONENTS

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Juraj Čuboň

2013-10-01

Full Text Available Milk production of 22 cows of Slovak Pied breed with Holstein-Friesian was analyzed according to the genetic variants of the polymorphic proteins determined by starch gel electrophoresis. The effect of genetic variants of the proteins was analyzed by selected properties of milk (milk yield, proteins, fats and lactose. Differences between the productive characters in testing groups were evaluated according to statistic method of t-test. Evaluation was carried out during throughout lactation. Based on the analyses we have obtained results frequency of genotypes: κ-CN AA in 9 cows (41%, AB in 12 cows (54.5% and BB in one cow, which is 4.5%. The average daily milk production of κ-CN AA was 13.5 l/day and in κ-CN AB 14.2 l/day. Contents of protein of genetic variation κ-CN AA was 3.1% in milk genotype κ-CN AB was found not significant lower protein proportion 3.0%. Based on the analyses, we can assume that cow’s nutrition higher influence the increase in the proportion of protein than polymorphism of κ-CN. In our research was found out the average fat content 4.0% in genetic variation of κ-CN AA and not significant lower in genetic variation κ-CN AB 3.8%. The average lactose content in the cow’s milk with κ-CN AA genotype was 4.9% and κ-CN AB was 5.0%. The difference between fat content wasn’t statistically significant.

Genetic component in learning ability in bees.

Science.gov (United States)

Kerr, W E; Moura Duarte, F A; Oliveira, R S

1975-10-01

Twenty-five bees, five from each of five hives, were trained to collect food at a table. When the bee reached the table, time was recorded for 12 visits. Then a blue and yellow pan was substituted for the original metal pan, and time and correct responses were recorded for 30 trips (discrimination phase). Finally, food was taken from the pan and extinction was recorded as incorrect responses for 20 visits. Variance analysis was carried out, and genetic variance was undetected for discrimination, but was detected for extinction. It is concluded that learning is very important for bees, so that any impairment in such ability affects colony survival.

Sex Determination, Sex Ratios, and Genetic Conflict

NARCIS (Netherlands)

Werren, John H.; Beukeboom, Leo W.

1998-01-01

Genetic mechanisms of sex determination are unexpectedly diverse and change rapidly during evolution. We review the role of genetic conflict as the driving force behind this diversity and turnover. Genetic conflict occurs when different components of a genetic system are subject to selection in

Colony formation of C57BL/6J mice in visible burrow system: Identification of eusocial behaviors in a background strain for genetic animal models of autism

OpenAIRE

Arakawa, Hiroyuki; Blanchard, D. Caroline; Blanchard, Robert J.

2006-01-01

Deficits in social interaction are primary characteristics of autism, which has strong genetic components. Genetically-manipulated mouse models may provide a useful research tool to advance the investigation of genes associated with autism. To identify these genes using mouse models, behavioral assays for social relationships in the background strains must be developed. The present study examined colony formation in groups of one male and three female mice (Experiment 1) and, groups of three ...

The genetic component of preeclampsia

DEFF Research Database (Denmark)

Hansen, Anette Tarp; Bernth Jensen, Jens Magnus; Hvas, Anne-Mette

2018-01-01

Preeclampsia is a major cause of maternal and perinatal deaths. The aetiology of preeclampsia is largely unknown but a polygenetic component is assumed. To explore this hypothesis, we performed an in-depth whole-exome sequencing study in women with (cases, N = 50) and without (controls, N = 50......) preeclampsia. The women were identified in an unselected cohort of 2,545 pregnant women based on data from the Danish National Patient Registry and the Medical Birth Registry. Matching DNA was obtained from a biobank containing excess blood from routine antenatal care visits. Novogene performed the whole......-exome sequencing blinded to preeclampsia status. Variants for comparison between cases and controls were filtered in the Ingenuity Variant Analysis software. We applied two different strategies; a disease association panel approach, which included variants in single genes associated with established clinical risk...

The relative importance of genetic and environmental effects for the early stages of thyroid autoimmunity

DEFF Research Database (Denmark)

Hansen, Pia S; Brix, Thomas H; Iachine, Ivan

2006-01-01

OBJECTIVE: In euthyroid individuals, autoantibodies to thyroid peroxidase (TPOab) and thyroglobulin (Tgab) are regarded as early markers of thyroid autoimmunity. Family and twin studies suggest that development of thyroid autoantibodies in first-degree relatives of patients with autoimmune thyroi....... The analyses suggest that it is the same set of genes that operate in males and females. However, complex mechanisms such as dominance and/or epistasis may be involved....... concordance and intraclass correlations were consistently higher for MZ than for DZ twin pairs indicating genetic influence. Genetic components (with 95% confidence intervals) accounted for 73% (46-89%) of the liability of being thyroid antibody positive. Adjusting for covariates (age, TSH and others......), the estimate for genetic influence on serum TPOab concentrations was 61% (49-70%) in males and 72% (64-79%) in females. For serum Tgab concentrations, the estimates were 39% (24-51%) and 75% (66-81%) respectively. CONCLUSIONS: Early markers of thyroid autoimmunity appear to be under strong genetic influence...

Common genetic variation and novel loci associated with volumetric mammographic density.

Science.gov (United States)

Brand, Judith S; Humphreys, Keith; Li, Jingmei; Karlsson, Robert; Hall, Per; Czene, Kamila

2018-04-17

Mammographic density (MD) is a strong and heritable intermediate phenotype of breast cancer, but much of its genetic variation remains unexplained. We conducted a genetic association study of volumetric MD in a Swedish mammography screening cohort (n = 9498) to identify novel MD loci. Associations with volumetric MD phenotypes (percent dense volume, absolute dense volume, and absolute nondense volume) were estimated using linear regression adjusting for age, body mass index, menopausal status, and six principal components. We also estimated the proportion of MD variance explained by additive contributions from single-nucleotide polymorphisms (SNP-based heritability [h 2 SNP ]) in 4948 participants of the cohort. In total, three novel MD loci were identified (at P associated with breast cancer in available meta-analysis data including 122,977 breast cancer cases and 105,974 control subjects (P < 0.05). h 2 SNP (SE) estimates for percent dense, absolute dense, and nondense volume were 0.29 (0.07), 0.31 (0.07), and 0.25 (0.07), respectively. Corresponding ratios of h 2 SNP to previously observed narrow-sense h 2 estimates in the same cohort were 0.46, 0.72, and 0.41, respectively. These findings provide new insights into the genetic basis of MD and biological mechanisms linking MD to breast cancer risk. Apart from identifying three novel loci, we demonstrate that at least 25% of the MD variance is explained by common genetic variation with h 2 SNP /h 2 ratios varying between dense and nondense MD components.

Quantification of genetically modified soya using strong anion exchange chromatography and time-of-flight mass spectrometry.

Science.gov (United States)

Chang, Po-Chih; Reddy, P Muralidhar; Ho, Yen-Peng

2014-09-01

Stable-isotope dimethyl labeling was applied to the quantification of genetically modified (GM) soya. The herbicide-resistant gene-related protein 5-enolpyruvylshikimate-3-phosphate synthase (CP4 EPSPS) was labeled using a dimethyl labeling reagent, formaldehyde-H2 or -D2. The identification and quantification of CP4 EPSPS was performed using matrix-assisted laser desorption/ionization mass spectrometry (MALDI-MS). The CP4 EPSPS protein was separated from high abundance proteins using strong anion exchange chromatography and sodium dodecyl sulfate-polyacrylamide gel electrophoresis. Then, the tryptic peptides from the samples and reference were labeled with formaldehyde-H2 and formaldehyde-D2, respectively. The two labeled pools were mixed and analyzed using MALDI-MS. The data showed a good correlation between the peak ratio of the H- and D-labeled peptides and the GM soya percentages at 0.5, 1, 3, and 5 %, with R (2) of 0.99. The labeling reagents are readily available. The labeling experiments and the detection procedures are simple. The approach is useful for the quantification of GM soya at a level as low as 0.5 %.

Analysis of genetic effects of nuclear-cytoplasmic interaction on quantitative traits: genetic model for diploid plants.

Science.gov (United States)

Han, Lide; Yang, Jian; Zhu, Jun

2007-06-01

A genetic model was proposed for simultaneously analyzing genetic effects of nuclear, cytoplasm, and nuclear-cytoplasmic interaction (NCI) as well as their genotype by environment (GE) interaction for quantitative traits of diploid plants. In the model, the NCI effects were further partitioned into additive and dominance nuclear-cytoplasmic interaction components. Mixed linear model approaches were used for statistical analysis. On the basis of diallel cross designs, Monte Carlo simulations showed that the genetic model was robust for estimating variance components under several situations without specific effects. Random genetic effects were predicted by an adjusted unbiased prediction (AUP) method. Data on four quantitative traits (boll number, lint percentage, fiber length, and micronaire) in Upland cotton (Gossypium hirsutum L.) were analyzed as a worked example to show the effectiveness of the model.

Chemosensory responsiveness to ethanol and its individual sensory components in alcohol-preferring, alcohol-nonpreferring and genetically heterogeneous rats.

Science.gov (United States)

Brasser, Susan M; Silbaugh, Bryant C; Ketchum, Myles J; Olney, Jeffrey J; Lemon, Christian H

2012-03-01

Alcohol activates orosensory circuits that project to motivationally relevant limbic forebrain areas that control appetite, feeding and drinking. To date, limited data exists regarding the contribution of chemosensory-derived ethanol reinforcement to ethanol preference and consumption. Measures of taste reactivity to intra-orally infused ethanol have not found differences in initial orofacial responses to alcohol between alcohol-preferring (P) and alcohol-non-preferring (NP) genetically selected rat lines. Yet, in voluntary intake tests, P rats prefer highly concentrated ethanol upon initial exposure, suggesting an early sensory-mediated attraction. Here, we directly compared self-initiated chemosensory responding for alcohol and prototypic sweet, bitter and oral trigeminal stimuli among selectively bred P, NP and non-selected Wistar (WI) outbred lines to determine whether differential sensory responsiveness to ethanol and its putative sensory components are phenotypically associated with genetically influenced alcohol preference. Rats were tested for immediate short-term lick responses to alcohol (3-40%), sucrose (0.01-1 M), quinine (0.01-3 mM) and capsaicin (0.003-1 mM) in a brief-access assay designed to index orosensory-guided behavior. P rats exhibited elevated short-term lick responses to both alcohol and sucrose relative to NP and WI lines across a broad range of concentrations of each stimulus and in the absence of blood alcohol levels that would produce significant post-absorptive effects. There was no consistent relationship between genetically mediated alcohol preference and orosensory avoidance of quinine or capsaicin. These data indicate that enhanced initial chemosensory attraction to ethanol and sweet stimuli are phenotypes associated with genetic alcohol preference and are considered within the framework of downstream activation of oral appetitive reward circuits. © 2011 The Authors, Addiction Biology © 2011 Society for the Study of

Insight into the Genetic Components of Community Genetics: QTL Mapping of Insect Association in a Fast-Growing Forest Tree

NARCIS (Netherlands)

DeWoody, J.; Viger, M.; Lakatos, F.; Tuba, K.; Taylor, G.; Smulders, M.J.M.

2013-01-01

Identifying genetic sequences underlying insect associations on forest trees will improve the understanding of community genetics on a broad scale. We tested for genomic regions associated with insects in hybrid poplar using quantitative trait loci (QTL) analyses conducted on data from a common

Candidate genes detected in transcriptome studies are strongly dependent on genetic background.

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Pernille Sarup

2011-01-01

Full Text Available Whole genome transcriptomic studies can point to potential candidate genes for organismal traits. However, the importance of potential candidates is rarely followed up through functional studies and/or by comparing results across independent studies. We have analysed the overlap of candidate genes identified from studies of gene expression in Drosophila melanogaster using similar technical platforms. We found little overlap across studies between putative candidate genes for the same traits in the same sex. Instead there was a high degree of overlap between different traits and sexes within the same genetic backgrounds. Putative candidates found using transcriptomics therefore appear very sensitive to genetic background and this can mask or override effects of treatments. The functional importance of putative candidate genes emerging from transcriptome studies needs to be validated through additional experiments and in future studies we suggest a focus on the genes, networks and pathways affecting traits in a consistent manner across backgrounds.

Application of molecular genetic tools for forest pathology

Science.gov (United States)

Mee-Sook Kim; John Hanna; Amy Ross-Davis; Ned Klopfenstein

2012-01-01

In recent years, advances in molecular genetics have provided powerful tools to address critical issues in forest pathology to help promote resilient forests. Although molecular genetic tools are initially applied to understand individual components of forest pathosystems, forest pathosystems involve dynamic interactions among biotic and abiotic components of the...

Control component retainer

International Nuclear Information System (INIS)

Walton, L.A.; King, R.A.

1983-01-01

An apparatus is described for retaining an undriven control component assembly disposed in a fuel assembly in a nuclear reactor of the type having a core grid plate. The first part of the mechanism involves a housing for the control component and the second part is a brace with a number of arms that reach under the grid plate. The brace and the housing are coupled together to firmly hold the control components in place even under strong flows of th coolant

Systematic genetic array analysis links the Saccharomyces cerevisiae SAGA/SLIK and NuA4 component Tra1 to multiple cellular processes

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Andrews Brenda

2008-07-01

Full Text Available Abstract Background Tra1 is an essential 437-kDa component of the Saccharomyces cerevisiae SAGA/SLIK and NuA4 histone acetyltransferase complexes. It is a member of a group of key signaling molecules that share a carboxyl-terminal domain related to phosphatidylinositol-3-kinase but unlike many family members, it lacks kinase activity. To identify genetic interactions for TRA1 and provide insight into its function we have performed a systematic genetic array analysis (SGA on tra1SRR3413, an allele that is defective in transcriptional regulation. Results The SGA analysis revealed 114 synthetic slow growth/lethal (SSL interactions for tra1SRR3413. The interacting genes are involved in a range of cellular processes including gene expression, mitochondrial function, and membrane sorting/protein trafficking. In addition many of the genes have roles in the cellular response to stress. A hierarchal cluster analysis revealed that the pattern of SSL interactions for tra1SRR3413 most closely resembles deletions of a group of regulatory GTPases required for membrane sorting/protein trafficking. Consistent with a role for Tra1 in cellular stress, the tra1SRR3413 strain was sensitive to rapamycin. In addition, calcofluor white sensitivity of the strain was enhanced by the protein kinase inhibitor staurosporine, a phenotype shared with the Ada components of the SAGA/SLIK complex. Through analysis of a GFP-Tra1 fusion we show that Tra1 is principally localized to the nucleus. Conclusion We have demonstrated a genetic association of Tra1 with nuclear, mitochondrial and membrane processes. The identity of the SSL genes also connects Tra1 with cellular stress, a result confirmed by the sensitivity of the tra1SRR3413 strain to a variety of stress conditions. Based upon the nuclear localization of GFP-Tra1 and the finding that deletion of the Ada components of the SAGA complex result in similar phenotypes as tra1SRR3413, we suggest that the effects of tra1SRR3413

Genetic Susceptibility to Vitiligo: GWAS Approaches for Identifying Vitiligo Susceptibility Genes and Loci

Science.gov (United States)

Shen, Changbing; Gao, Jing; Sheng, Yujun; Dou, Jinfa; Zhou, Fusheng; Zheng, Xiaodong; Ko, Randy; Tang, Xianfa; Zhu, Caihong; Yin, Xianyong; Sun, Liangdan; Cui, Yong; Zhang, Xuejun

2016-01-01

Vitiligo is an autoimmune disease with a strong genetic component, characterized by areas of depigmented skin resulting from loss of epidermal melanocytes. Genetic factors are known to play key roles in vitiligo through discoveries in association studies and family studies. Previously, vitiligo susceptibility genes were mainly revealed through linkage analysis and candidate gene studies. Recently, our understanding of the genetic basis of vitiligo has been rapidly advancing through genome-wide association study (GWAS). More than 40 robust susceptible loci have been identified and confirmed to be associated with vitiligo by using GWAS. Most of these associated genes participate in important pathways involved in the pathogenesis of vitiligo. Many susceptible loci with unknown functions in the pathogenesis of vitiligo have also been identified, indicating that additional molecular mechanisms may contribute to the risk of developing vitiligo. In this review, we summarize the key loci that are of genome-wide significance, which have been shown to influence vitiligo risk. These genetic loci may help build the foundation for genetic diagnosis and personalize treatment for patients with vitiligo in the future. However, substantial additional studies, including gene-targeted and functional studies, are required to confirm the causality of the genetic variants and their biological relevance in the development of vitiligo. PMID:26870082

The capture of heritable variation for genetic quality through social competition.

Science.gov (United States)

Wolf, Jason B; Harris, W Edwin; Royle, Nick J

2008-09-01

In theory, females of many species choose mates based on traits that are indicators of male genetic quality. A fundamental question in evolutionary biology is why genetic variation for such indicator traits persists despite strong persistent selection imposed by female preference, which is known as the lek paradox. One potential solution to the lek paradox suggests that the traits that are targets of mate choice should evolve condition-dependent expression and that condition should have a large genetic variance. Condition is expected to exhibit high genetic variance because it is affected by a large number of physiological processes and hence, condition-dependent traits should 'capture' variation contributed by a large number of loci. We suggest that a potentially important cause of variation in condition is competition for limited resources. Here, we discuss a pair of models to analyze the evolutionary genetics of traits affected by success in social competition for resources. We show that competition can contribute to genetic variation of 'competition-dependent' traits that have fundamentally different evolutionary properties than other sources of variation. Competition dependence can make traits honest indicators of genetic quality by revealing the relative competitive ability of males, can provide a component of heritable variation that does not contribute to trait evolution, and can help maintain heritable variation under directional selection. Here we provide a general introduction to the concept of competition dependence and briefly introduce two models to demonstrate the potential evolutionary consequences of competition-dependent trait expression.

Kinetics of methane fermentation yield in biogas reactors: Genetic variation and association with chemical composition in maize

International Nuclear Information System (INIS)

Grieder, Christoph; Mittweg, Greta; Dhillon, Baldev S.; Montes, Juan M.; Orsini, Elena; Melchinger, Albrecht E.

2012-01-01

Maize (Zea mays L.) is the most competitive crop for methane production in Germany. Methane fermentation yield per unit of dry matter (MFY) is a determinant of methane yield, but little information is available on this trait. Our objectives were to investigate the kinetics of MFY during fermentation of maize, estimate quantitative-genetic parameters for different traits related to MFY and examine the relationship of MFY with chemical composition and silage quality. Whole-plant material of 16 inbreds and their 32 testcrosses was analyzed for MFY over 35 days of fermentation using a discontinuous laboratory assay. Data were also generated on chemical composition and in vitro digestible organic matter (IVDOM). Significant genotypic variances and high heritabilities were observed for MFY at early fermentation stages (up to 5 days) probably due to different concentrations of easily degradable chemical components. However, genotypic variances and heritability of MFY reduced as fermentation progressed, because of complete or partial degradation of all chemical components. Further, there were strong correlations of MFY with chemical components at early fermentation stages but not at later stages. Therefore, MFY at later stages, which is closer to potential MFY, does not seem to be amenable to selection. High heritability of IVDOM and its strong correlation with MFY in testcrosses indicated its possible use for preliminary or indirect selection. Keeping in view the magnitude of genetic variance that was low for MFY and high for dry matter yield (DMY), the other component of methane yield, more emphasis on breeding for DMY seems appropriate. -- Highlights: ► We investigated methane fermentation yield (MFY) of diverse germplasm of maize. ► The kinetics of MFY and its correlations with chemical composition were examined. ► Genetic variance and heritability for MFY decreased with fermentation time. ► Complete fermentation (35 d) reduced correlations of MFY with chemical

Elevational patterns of genetic variation in the cosmopolitan moss Bryum argenteum (Bryaceae).

Science.gov (United States)

Pisa, Sergio; Werner, Olaf; Vanderpoorten, Alain; Magdy, Mahmoud; Ros, Rosa M

2013-10-01

The Baas Becking tenet posits that 'everything is everywhere, but the environment selects' to explain cosmopolitan distributions in highly vagile taxa. Bryophyte species show wider distributions than vascular plants and include examples of truly cosmopolitan ranges, which have been interpreted as a result of high dispersal capacities and ecological plasticity. In the current study, we documented patterns of genetic structure and diversity in the cosmopolitan moss Bryum argenteum along an elevational gradient to determine if genetic diversity and structure is homogenized by intense migrations in the lack of ecological differentiation. • 60 specimens were collected in the Sierra Nevada Mountains (Spain) between 100 and 2870 m and sequenced for ITS and rps4. Comparative analyses, genetic diversity estimators, and Mantel's tests were employed to determine the relationship between genetic variation, elevation, and geographic distance and to look for signs of demographic shifts. • Genetic diversity peaked above 1900 m and no signs of demographic shifts were detected at any elevation. There was a strong phylogenetic component in elevational variation. Genetic variation was significantly correlated with elevation, but not with geographic distance. • The results point to the long-term persistence of Bryum argenteum in a range that was glaciated during the Late Pleistocene. Evidence for an environmentally driven pattern of genetic differentiation suggests adaptive divergence. This supports the Baas Becking tenet and indicates that ecological specialization might play a key role in explaining patterns of genetic structure in cosmopolitan mosses.

Dynamics of a strongly driven two-component Bose-Einstein condensate

International Nuclear Information System (INIS)

Salmond, G.L.; Holmes, C.A.; Milburn, G.J.

2002-01-01

We consider a two-component Bose-Einstein condensate in two spatially localized modes of a double-well potential, with periodic modulation of the tunnel coupling between the two modes. We treat the driven quantum field using a two-mode expansion and define the quantum dynamics in terms of the Floquet Operator for the time periodic Hamiltonian of the system. It has been shown that the corresponding semiclassical mean-field dynamics can exhibit regions of regular and chaotic motion. We show here that the quantum dynamics can exhibit dynamical tunneling between regions of regular motion, centered on fixed points (resonances) of the semiclassical dynamics

Polygyny and strong genetic structuring within an isolated population of the wood ant Formica rufa

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Wouter Dekoninck

2014-12-01

Full Text Available Social structuring of populations within some Formica species exhibits considerable variation going from monodomous and monogynous populations to polydomous, polygynous populations. The wood ant species Formica rufa appears to be mainly monodomous and monogynous throughout most of its distribution area in central and northern Europe. Only occasionally it was mentioned that F. rufa can have both polygynous and monogynous colonies in the same geographical region. We studied an isolated polydomous F. rufa population in a deciduous mixed forest in the north-west of Belgium. The level of polydomy within the colonies varied from monodomous to 11 nests per colony. Our genetic analysis of eight variable microsatellites suggest an oligo- to polygynous structure for at least the major part of the sampled nests. Relatedness amongst nest mate workers varies considerable within the population and colonies but confirms in general a polygynous structure. Additionally high genetic diversity (e.g. up to 8 out of 11 alleles per nest for the most variable locus and high within nest genetic variance (93% indicate that multiple queens contribute to the gene pool of workers of the same nest. Moreover significant genetic structuring among colonies indicates that gene flow between colonies is restricted and that exchange of workers between colonies is very limited. Finally we explain how possible factors as budding and the absence of Serviformica can explain the differences in genetic structure within this polygynous F. rufa population.

Automatic Creation of Machine Learning Workflows with Strongly Typed Genetic Programming

Czech Academy of Sciences Publication Activity Database

Křen, T.; Pilát, M.; Neruda, Roman

2017-01-01

Roč. 26, č. 5 (2017), č. článku 1760020. ISSN 0218-2130 R&D Projects: GA ČR GA15-19877S Grant - others:GA MŠk(CZ) LM2015042 Institutional support: RVO:67985807 Keywords : genetic programming * machine learning workflows * asynchronous evolutionary algorithm Subject RIV: IN - Informatics, Computer Science OBOR OECD: Computer sciences, information science, bioinformathics (hardware development to be 2.2, social aspect to be 5.8) Impact factor: 0.778, year: 2016

Mapping determinants of gene expression plasticity by genetical genomics in C. elegans.

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Yang Li

2006-12-01

Full Text Available Recent genetical genomics studies have provided intimate views on gene regulatory networks. Gene expression variations between genetically different individuals have been mapped to the causal regulatory regions, termed expression quantitative trait loci. Whether the environment-induced plastic response of gene expression also shows heritable difference has not yet been studied. Here we show that differential expression induced by temperatures of 16 degrees C and 24 degrees C has a strong genetic component in Caenorhabditis elegans recombinant inbred strains derived from a cross between strains CB4856 (Hawaii and N2 (Bristol. No less than 59% of 308 trans-acting genes showed a significant eQTL-by-environment interaction, here termed plasticity quantitative trait loci. In contrast, only 8% of an estimated 188 cis-acting genes showed such interaction. This indicates that heritable differences in plastic responses of gene expression are largely regulated in trans. This regulation is spread over many different regulators. However, for one group of trans-genes we found prominent evidence for a common master regulator: a transband of 66 coregulated genes appeared at 24 degrees C. Our results suggest widespread genetic variation of differential expression responses to environmental impacts and demonstrate the potential of genetical genomics for mapping the molecular determinants of phenotypic plasticity.

Self-gravito-acoustic shock structures in a self-gravitating, strongly coupled, multi-component, degenerate quantum plasma system

Science.gov (United States)

Mamun, A. A.

2017-10-01

The existence of self-gravito-acoustic (SGA) shock structures (SSs) associated with negative self-gravitational potential in a self-gravitating, strongly coupled, multi-component, degenerate quantum plasma (SGSCMCDQP) system is predicted for the first time. The modified Burgers (MB) equation, which is valid for both planar and non-planar (spherical) geometries, is derived analytically, and solved numerically. It is shown that the longitudinal viscous force acting on inertial plasma species of the plasma system is the source of dissipation and is responsible for the formation of these SGA SSs in the plasma system. The time evolution of these SGA SSs is also shown for different values (viz., 0.5, 1, and 2) of Γ, where Γ is the ratio of the nonlinear coefficient to the dissipative coefficient in the MB equation. The SGSCMCDQP model and the numerical analysis of the MB equation presented here are so general that they can be applied in any type of SGSCMCDQP systems like astrophysical compact objects having planar or non-planar (spherical) shape.

Strong genetic differentiation among east Atlantic populations of the sword razor shell ( Ensis siliqua) assessed with mtDNA and RAPD markers

Science.gov (United States)

Arias, Alberto; Fernández-Moreno, Mercedes; Fernández-Tajes, Juan; Gaspar, Miguel B.; Méndez, Josefina

2011-03-01

The sword razor shell Ensis siliqua (Linnaeus, 1758) is a bivalve with a high commercial value being appreciated in fresh and processed markets. However, the genetic studies carried out in populations of E. siliqua are scarce. In this work, the genetic variability and differentiation of the sword razor shell was assessed using PCR-RFLPs of a fragment of the 16S rRNA mitochondrial gene and random amplified polymorphic loci (RAPD) in nine localities from Ireland, Spain, and Portugal. In the 314 individuals examined for the mitochondrial fragment, 12 composite haplotypes were observed; meanwhile, a unique phenotype was observed for each of the 242 individuals analyzed with 61 RAPD loci. Two of the mitochondrial composite haplotypes accounted for the majority of individuals (89.81%) and showed a remarkably disjoint distribution between Irish and Iberian samples, with the exception of Aveiro which exhibited as the most frequent haplotype the same found in Ireland. The level of variability observed for each sample was generally correlated with both types of markers and the results obtained suggest the existence of a strong population differentiation between Irish and Iberian localities, except for the Portuguese sample from Aveiro which is surprisingly closer to Irish individuals, although it is probably highly differentiated.

Supporting aboriginal knowledge and practice in health care: lessons from a qualitative evaluation of the strong women, strong babies, strong culture program.

Science.gov (United States)

Lowell, Anne; Kildea, Sue; Liddle, Marlene; Cox, Barbara; Paterson, Barbara

2015-02-05

The Strong Women, Strong Babies, Strong Culture Program (the Program) evolved from a recognition of the value of Aboriginal knowledge and practice in promoting maternal and child health (MCH) in remote communities of the Northern Territory (NT) of Australia. Commencing in 1993 it continues to operate today. In 2008, the NT Department of Health commissioned an evaluation to identify enabling factors and barriers to successful implementation of the Program, and to identify potential pathways for future development. In this paper we focus on the evaluation findings related specifically to the role of Aborignal cultural knowledge and practice within the Program. A qualitative evaluation utilised purposive sampling to maximise diversity in program history and Aboriginal culture. Semi-structured, in-depth interviews with 76 participants were recorded in their preferred language with a registered Interpreter when required. Thematic analysis of data was verified or modified through further discussions with participants and members of the evaluation team. Although the importance of Aboriginal knowledge and practice as a fundamental component of the Program is widely acknowledged, there has been considerable variation across time and location in the extent to which these cultural dimensions have been included in practice. Factors contributing to this variation are complex and relate to a number of broad themes including: location of control over Program activities; recognition and respect for Aboriginal knowledge and practice as a legitimate component of health care; working in partnership; communication within and beyond the Program; access to transport and working space; and governance and organisational support. We suggest that inclusion of Aboriginal knowledge and practice as a fundamental component of the Program is key to its survival over more than twenty years despite serious challenges. Respect for the legitimacy of Aboriginal knowledge and practice within health

Assessing the impact of a combined analysis of four common low-risk genetic variants on autism risk

Directory of Open Access Journals (Sweden)

Carayol Jerome

2010-02-01

Full Text Available Abstract Background Autism is a complex disorder characterized by deficits involving communication, social interaction, and repetitive and restrictive patterns of behavior. Twin studies have shown that autism is strongly heritable, suggesting a strong genetic component. In other disease states with a complex etiology, such as type 2 diabetes, cancer and cardiovascular disease, combined analysis of multiple genetic variants in a genetic score has helped to identify individuals at high risk of disease. Genetic scores are designed to test for association of genetic markers with disease. Method The accumulation of multiple risk alleles markedly increases the risk of being affected, and compared with studying polymorphisms individually, it improves the identification of subgroups of individuals at greater risk. In the present study, we show that this approach can be applied to autism by specifically looking at a high-risk population of children who have siblings with autism. A two-sample study design and the generation of a genetic score using multiple independent genes were used to assess the risk of autism in a high-risk population. Results In both samples, odds ratios (ORs increased significantly as a function of the number of risk alleles, with a genetic score of 8 being associated with an OR of 5.54 (95% confidence interval [CI] 2.45 to 12.49. The sensitivities and specificities for each genetic score were similar in both analyses, and the resultant area under the receiver operating characteristic curves were identical (0.59. Conclusions These results suggest that the accumulation of multiple risk alleles in a genetic score is a useful strategy for assessing the risk of autism in siblings of affected individuals, and may be better than studying single polymorphisms for identifying subgroups of individuals with significantly greater risk.

Enriching an intraspecific genetic map and identifying QTL for fiber quality and yield component traits across multiple environments in Upland cotton (Gossypium hirsutum L.).

Science.gov (United States)

Liu, Xueying; Teng, Zhonghua; Wang, Jinxia; Wu, Tiantian; Zhang, Zhiqin; Deng, Xianping; Fang, Xiaomei; Tan, Zhaoyun; Ali, Iftikhar; Liu, Dexin; Zhang, Jian; Liu, Dajun; Liu, Fang; Zhang, Zhengsheng

2017-12-01

Cotton is a significant commercial crop that plays an indispensable role in many domains. Constructing high-density genetic maps and identifying stable quantitative trait locus (QTL) controlling agronomic traits are necessary prerequisites for marker-assisted selection (MAS). A total of 14,899 SSR primer pairs designed from the genome sequence of G. raimondii were screened for polymorphic markers between mapping parents CCRI 35 and Yumian 1, and 712 SSR markers showing polymorphism were used to genotype 180 lines from a (CCRI 35 × Yumian 1) recombinant inbred line (RIL) population. Genetic linkage analysis was conducted on 726 loci obtained from the 712 polymorphic SSR markers, along with 1379 SSR loci obtained in our previous study, and a high-density genetic map with 2051 loci was constructed, which spanned 3508.29 cM with an average distance of 1.71 cM between adjacent markers. Marker orders on the linkage map are highly consistent with the corresponding physical orders on a G. hirsutum genome sequence. Based on fiber quality and yield component trait data collected from six environments, 113 QTLs were identified through two analytical methods. Among these 113 QTLs, 50 were considered stable (detected in multiple environments or for which phenotypic variance explained by additive effect was greater than environment effect), and 18 of these 50 were identified with stability by both methods. These 18 QTLs, including eleven for fiber quality and seven for yield component traits, could be priorities for MAS.

Genetic and other risk factors for suicidal ideation and the relationship with depression.

Science.gov (United States)

Dutta, R; Ball, H A; Siribaddana, S H; Sumathipala, A; Samaraweera, S; McGuffin, P; Hotopf, M

2017-10-01

There is a genetic contribution to the risk of suicide, but sparse prior research on the genetics of suicidal ideation. Active and passive suicidal ideation were assessed in a Sri Lankan population-based twin registry (n = 3906 twins) and a matched non-twin sample (n = 2016). Logistic regression models were used to examine associations with socio-demographic factors, environmental exposures and psychiatric symptoms. The heritability of suicidal ideation was assessed using structural equation modelling. The lifetime prevalence of any suicidal ideation was 13.0% (11.7-14.3%) for men; 21.8% (20.3-23.2%) for women, with no significant difference between twins and non-twins. Factors that predicted suicidal ideation included female gender, termination of marital relationship, low education level, urban residence, losing a parent whilst young, low standard of living and stressful life events in the preceding 12 months. Suicidal ideation was strongly associated with depression, but also with abnormal fatigue and alcohol and tobacco use. The best fitting structural equation model indicated a substantial contribution from genetic factors (57%; CI 47-66) and from non-shared environmental factors (43%; CI 34-53) in both men and women. In women this genetic component was largely mediated through depression, but in men there was a significant heritable component to suicidal ideation that was independent of depression. These are the first results to show a genetic contribution to suicidal ideation that is independent of depression outside of a high-income country. These phenomena may be generalizable, because previous research highlights similarities between the aetiology of mental disorders in Sri Lanka and higher-income countries.

Genetic analysis of growth traits in Polled Nellore cattle raised on pasture in tropical region using Bayesian approaches.

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Lopes, Fernando Brito; Magnabosco, Cláudio Ulhôa; Paulini, Fernanda; da Silva, Marcelo Corrêa; Miyagi, Eliane Sayuri; Lôbo, Raysildo Barbosa

2013-01-01

Components of (co)variance and genetic parameters were estimated for adjusted weights at ages 120 (W120), 240 (W240), 365 (W365) and 450 (W450) days of Polled Nellore cattle raised on pasture and born between 1987 and 2010. Analyses were performed using an animal model, considering fixed effects: herd-year-season of birth and calf sex as contemporary groups and the age of cow as a covariate. Gibbs Samplers were used to estimate (co)variance components, genetic parameters and additive genetic effects, which accounted for great proportion of total variation in these traits. High direct heritability estimates for the growth traits were revealed and presented mean 0.43, 0.61, 0.72 and 0.67 for W120, W240, W365 and W450, respectively. Maternal heritabilities were 0.07 and 0.08 for W120 and W240, respectively. Direct additive genetic correlations between the weight at 120, 240, 365 and 450 days old were strong and positive. These estimates ranged from 0.68 to 0.98. Direct-maternal genetic correlations were negative for W120 and W240. The estimates ranged from -0.31 to -0.54. Estimates of maternal heritability ranged from 0.056 to 0.092 for W120 and from 0.064 to 0.096 for W240. This study showed that genetic progress is possible for the growth traits we studied, which is a novel and favorable indicator for an upcoming and promising Polled Zebu breed in Tropical regions. Maternal effects influenced the performance of weight at 120 and 240 days old. These effects should be taken into account in genetic analyses of growth traits by fitting them as a genetic or a permanent environmental effect, or even both. In general, due to a medium-high estimate of environmental (co)variance components, management and feeding conditions for Polled Nellore raised at pasture in tropical regions of Brazil needs improvement and growth performance can be enhanced.

Web-based genome-wide association study identifies two novel loci and a substantial genetic component for Parkinson's disease.

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Chuong B Do

2011-06-01

Full Text Available Although the causes of Parkinson's disease (PD are thought to be primarily environmental, recent studies suggest that a number of genes influence susceptibility. Using targeted case recruitment and online survey instruments, we conducted the largest case-control genome-wide association study (GWAS of PD based on a single collection of individuals to date (3,426 cases and 29,624 controls. We discovered two novel, genome-wide significant associations with PD-rs6812193 near SCARB2 (p = 7.6 × 10(-10, OR = 0.84 and rs11868035 near SREBF1/RAI1 (p = 5.6 × 10(-8, OR = 0.85-both replicated in an independent cohort. We also replicated 20 previously discovered genetic associations (including LRRK2, GBA, SNCA, MAPT, GAK, and the HLA region, providing support for our novel study design. Relying on a recently proposed method based on genome-wide sharing estimates between distantly related individuals, we estimated the heritability of PD to be at least 0.27. Finally, using sparse regression techniques, we constructed predictive models that account for 6%-7% of the total variance in liability and that suggest the presence of true associations just beyond genome-wide significance, as confirmed through both internal and external cross-validation. These results indicate a substantial, but by no means total, contribution of genetics underlying susceptibility to both early-onset and late-onset PD, suggesting that, despite the novel associations discovered here and elsewhere, the majority of the genetic component for Parkinson's disease remains to be discovered.

Expanding Possibilities for Intervention against Small Ruminant Lentiviruses through Genetic Marker-Assisted Selective Breeding

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Donald P. Knowles

2013-06-01

Full Text Available Small ruminant lentiviruses include members that infect sheep (ovine lentivirus [OvLV]; also known as ovine progressive pneumonia virus/maedi-visna virus and goats (caprine arthritis encephalitis virus [CAEV]. Breed differences in seroprevalence and proviral concentration of OvLV had suggested a strong genetic component in susceptibility to infection by OvLV in sheep. A genetic marker test for susceptibility to OvLV has been developed recently based on the TMEM154 gene with validation data from over 2,800 sheep representing nine cohorts. While no single genotype has been shown to have complete resistance to OvLV, consistent association in thousands of sheep from multiple breeds and management conditions highlight a new strategy for intervention by selective breeding. This genetic marker-assisted selection (MAS has the potential to be a useful addition to existing viral control measures. Further, the discovery of multiple additional genomic regions associated with susceptibility to or control of OvLV suggests that additional genetic marker tests may be developed to extend the reach of MAS in the future. This review will cover the strengths and limitations of existing data from host genetics as an intervention and outline additional questions for future genetic research in sheep, goats, small ruminant lentiviruses, and their host-pathogen interactions.

Expanding Possibilities for Intervention against Small Ruminant Lentiviruses through Genetic Marker-Assisted Selective Breeding

Science.gov (United States)

White, Stephen N.; Knowles, Donald P.

2013-01-01

Small ruminant lentiviruses include members that infect sheep (ovine lentivirus [OvLV]; also known as ovine progressive pneumonia virus/maedi-visna virus) and goats (caprine arthritis encephalitis virus [CAEV]). Breed differences in seroprevalence and proviral concentration of OvLV had suggested a strong genetic component in susceptibility to infection by OvLV in sheep. A genetic marker test for susceptibility to OvLV has been developed recently based on the TMEM154 gene with validation data from over 2,800 sheep representing nine cohorts. While no single genotype has been shown to have complete resistance to OvLV, consistent association in thousands of sheep from multiple breeds and management conditions highlight a new strategy for intervention by selective breeding. This genetic marker-assisted selection (MAS) has the potential to be a useful addition to existing viral control measures. Further, the discovery of multiple additional genomic regions associated with susceptibility to or control of OvLV suggests that additional genetic marker tests may be developed to extend the reach of MAS in the future. This review will cover the strengths and limitations of existing data from host genetics as an intervention and outline additional questions for future genetic research in sheep, goats, small ruminant lentiviruses, and their host-pathogen interactions. PMID:23771240

Web components and the semantic web

OpenAIRE

Casey, Maire; Pahl, Claus

2003-01-01

Component-based software engineering on the Web differs from traditional component and software engineering. We investigate Web component engineering activites that are crucial for the development,com position, and deployment of components on the Web. The current Web Services and Semantic Web initiatives strongly influence our work. Focussing on Web component composition we develop description and reasoning techniques that support a component developer in the composition activities,fo cussing...

Genetic testing and its implications: human genetics researchers grapple with ethical issues.

Science.gov (United States)

Rabino, Isaac

2003-01-01

To better understand ethical issues involved in the field of human genetics and promote debate within the scientific community, the author surveyed scientists who engage in human genetics research about the pros, cons, and ethical implications of genetic testing. This study contributes systematic data on attitudes of scientific experts. The survey finds respondents are highly supportive of voluntary testing and the right to know one's genetic heritage. The majority consider in utero testing and consequent pregnancy termination acceptable for cases involving likelihood of serious disease but disapprove for genetic reasons they consider arbitrary, leaving a gray area of distinguishing between treatment of disorders and enhancement still to be resolved. While safeguarding patient confidentiality versus protecting at-risk third parties (kin, reproductive partners) presents a dilemma, preserving privacy from misuse by institutional third parties (employers, insurers) garners strong consensus for legislation against discrimination. Finally, a call is made for greater genetic literacy.

Public understandings of genetics and health.

Science.gov (United States)

Condit, C M

2010-01-01

This review of adult public understandings of genetics related to health indicates that the public's understandings overlap with those of professionals in some areas, but not others. Specifically, the majority of the world's people who have been studied understand genetics through the lens of heredity, not in terms of the structural and functional nature of genes. Public understandings of hereditary processes are influenced by models of social relationships and by experiential familiarity with particular conditions as much as by academic research results. Most people hold a fairly strong belief that many health conditions are substantially influenced by both genes and other factors. However, they do not have a stable understanding of the nature of gene-environment interactions. People in cultures where science is not a prominent cultural mode are even less likely to hold the belief structures of professional geneticists. In some areas--notably with regard to racialization of genetic medicine and characterizations of genetic variations as 'mutations'--at least some members of the public strongly reject some geneticists' constructions. Public understanding of details pertinent to genetic testing generally appears to be weak.

Primary prevention in patients with a strong family history of coronary heart disease.

Science.gov (United States)

Burke, Lora A

2003-01-01

The interplay of genetic and environmental factors places first-degree relatives of individuals with premature coronary heart disease at greater risk of developing the disease than the general population. Disease processes, such as dyslipidemia, hypertension, and glucose and insulin metabolism, and lifestyle habits, such as eating and exercise patterns, as well as socioeconomic status aggregate in families with coronary heart disease. The degree of risk associated with a family history varies with the degree of relationship and the age at onset of disease. All individuals with a family history of premature heart disease should have a thorough coronary risk assessment performed, which can be initiated in an office visit. Absolute risk for coronary heart disease determination will predict the intensity of preventive interventions. This article reviews the components of risk determination and primary prevention in individuals with a strong family history of coronary heart disease.

Reduced larval feeding rate is a strong evolutionary correlate of ...

Indian Academy of Sciences (India)

Home; Journals; Journal of Genetics; Volume 85; Issue 3. Reduced larval feeding rate is a strong evolutionary correlate of rapid development in Drosophila melanogaster. M. Rajamani N. Raghavendra ... Keywords. life-history evolution; development time; larval feeding rate; competition; tradeoffs; Drosophila melanogaster.

Cosmological applications of strong gravitational lensing

DEFF Research Database (Denmark)

Paraficz, Danuta

value of the energy density of the two above components, together with measuring the Hubble constant that determines the age of the Universe, is a major goal of modern astrophysics. An interesting method for estimating these parameters is strong gravitational lensing of quasars (QSOs). As shown...

Genome wide association studies on yield components using a lentil genetic diversity panel

Science.gov (United States)

The cool season food legume research community are now at the threshold of deploying the cutting-edge molecular genetics and genomics tools that have led to significant and rapid expansion of gene discovery, knowledge of gene function (including tolerance to biotic and abiotic stresses) and genetic ...

Genetic variability of the pattern of night melatonin blood levels in relation to coat changes development in rabbits

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Chemineau Philippe

2004-03-01

Full Text Available Abstract To assess the genetic variability in both the nocturnal increase pattern of melatonin concentration and photoresponsiveness in coat changes, an experiment on 422 Rex rabbits (from 23 males raised under a constant light programme from birth was performed. The animals were sampled at 12 weeks of age, according to 4 periods over a year. Blood samples were taken 7 times during the dark phase and up to 1 h after the lighting began. Maturity of the fur was assessed at pelting. Heritability estimates of blood melatonin concentration (0.42, 0.17 and 0.11 at mid-night, 13 and 15 h after lights-out respectively and strong genetic correlations between fur maturity and melatonin levels at the end of the dark phase (-0.64 indicates that (i the variability of the nocturnal pattern of melatonin levels is under genetic control and (ii the duration of the nocturnal melatonin increase is a genetic component of photoresponsiveness in coat changes.

Experiencing the genetic body: parents' encounters with pediatric clinical genetics.

Science.gov (United States)

Raspberry, Kelly; Skinner, Debra

2007-01-01

Because of advancements in genetic research and technologies, the clinical practice of genetics is becoming a prevalent component of biomedicine. As the genetic basis for more and more diseases are found, it is possible that ways of experiencing health, illness, identity, kin relations, and the body are becoming geneticized, or understood within a genetic model of disease. Yet, other models and relations that go beyond genetic explanations also shape interpretations of health and disease. This article explores how one group of individuals for whom genetic disorder is highly relevant formulates their views of the body in light of genetic knowledge. Using data from an ethnographic study of 106 parents or potential parents of children with known or suspected genetic disorders who were referred to a pediatric genetic counseling and evaluation clinic in the southeastern United States, we find that these parents do, to some degree, perceive of their children's disorders in terms of a genetic body that encompasses two principal qualities: a sense of predetermined health and illness and an awareness of a profound historicity that reaches into the past and extends into the present and future. They experience this genetic body as both fixed and historical, but they also express ideas of a genetic body made less deterministic by their own efforts and future possibilities. This account of parents' experiences with genetics and clinical practice contributes to a growing body of work on the ways in which genetic information and technologies are transforming popular and medical notions of the body, and with it, health, illness, kinship relations, and personal and social identities.

Insight into the genetics of hypertension, a core component of the metabolic syndrome

Czech Academy of Sciences Publication Activity Database

Pravenec, Michal; Petretto, E.

2008-01-01

Roč. 11, - (2008), s. 393-397 ISSN 1363-1950 Grant - others:HHMI(US) 55005624; EURATOOLS(XE) LSHG-CT-2005-019015 Institutional research plan: CEZ:AV0Z50110509 Keywords : genetics * hypertension * genome-wide association studies Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 3.690, year: 2008

[The practice and discussion of the physical knowledge stepping into genetics teaching].

Science.gov (United States)

Luo, Shen; Luo, Peigao

2014-09-01

Genetics, one of the core courses of biological field, play a key role in biology teaching and research. In fact, there exists high similarity between many genetic knowledge and physical knowledge. Due to strong abstract of genetic contents and the weak basis of genetics, some students lack of interests to study genetics. How to apply the strong physical knowledge which students had been learned in the middle school in genetics teaching is worthwhile for genetics teachers. In this paper, we would like to introduce an infiltrative teaching model on applying physical knowledge into genetic contents by establishing the intrinsic logistic relationship between physical knowledge and genetic knowledge. This teaching model could help students more deeply understand genetic knowledge and enhance students' self-studying ability as well as creating ability.

A rapid, strong, and convergent genetic response to urban habitat fragmentation in four divergent and widespread vertebrates.

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Kathleen Semple Delaney

2010-09-01

Full Text Available Urbanization is a major cause of habitat fragmentation worldwide. Ecological and conservation theory predicts many potential impacts of habitat fragmentation on natural populations, including genetic impacts. Habitat fragmentation by urbanization causes populations of animals and plants to be isolated in patches of suitable habitat that are surrounded by non-native vegetation or severely altered vegetation, asphalt, concrete, and human structures. This can lead to genetic divergence between patches and in turn to decreased genetic diversity within patches through genetic drift and inbreeding.We examined population genetic patterns using microsatellites in four common vertebrate species, three lizards and one bird, in highly fragmented urban southern California. Despite significant phylogenetic, ecological, and mobility differences between these species, all four showed similar and significant reductions in gene flow over relatively short geographic and temporal scales. For all four species, the greatest genetic divergence was found where development was oldest and most intensive. All four animals also showed significant reduction in gene flow associated with intervening roads and freeways, the degree of patch isolation, and the time since isolation.Despite wide acceptance of the idea in principle, evidence of significant population genetic changes associated with fragmentation at small spatial and temporal scales has been rare, even in smaller terrestrial vertebrates, and especially for birds. Given the striking pattern of similar and rapid effects across four common and widespread species, including a volant bird, intense urbanization may represent the most severe form of fragmentation, with minimal effective movement through the urban matrix.

A Genealogical Interpretation of Principal Components Analysis

Science.gov (United States)

McVean, Gil

2009-01-01

Principal components analysis, PCA, is a statistical method commonly used in population genetics to identify structure in the distribution of genetic variation across geographical location and ethnic background. However, while the method is often used to inform about historical demographic processes, little is known about the relationship between fundamental demographic parameters and the projection of samples onto the primary axes. Here I show that for SNP data the projection of samples onto the principal components can be obtained directly from considering the average coalescent times between pairs of haploid genomes. The result provides a framework for interpreting PCA projections in terms of underlying processes, including migration, geographical isolation, and admixture. I also demonstrate a link between PCA and Wright's fst and show that SNP ascertainment has a largely simple and predictable effect on the projection of samples. Using examples from human genetics, I discuss the application of these results to empirical data and the implications for inference. PMID:19834557

So far away, yet so close: strong genetic structure in Homonota uruguayensis (Squamata, Phyllodactylidae, a species with restricted geographic distribution in the Brazilian and Uruguayan Pampas.

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Jéssica F Felappi

Full Text Available The Pampas is a biologically rich South American biome, but is poorly represented in phylogeographic studies. While the Pleistocene glacial cycles may have affected the evolutionary history of species distributed in forested biomes, little is known about their effects on the habitats that remained stable through glacial cycles. The South American Pampas have been covered by grasslands during both glacial and interglacial periods and therefore represent an interesting system to test whether the genetic structure in such environments is less pronounced. In this study, we sampled Pampean populations of Homonota uruguayensis from Southern Brazil and Uruguay to assess the tempo and mode of population divergence, using both morphological measurements and molecular markers. Our results indicate that, in spite of its narrow geographic distribution, populations of H. uruguayensis show high levels of genetic structure. We found four major well-supported mtDNA clades with strong geographic associations. Estimates of their divergence times fell between 3.16 and 1.82 million years before the present. Populations from the central portion of the species distribution, on the border between Uruguay and Brazil, have high genetic diversity and may have undergone a population expansion approximately 250,000 years before the present. The high degree of genetic structure is reflected in the analyses of morphological characters, and most individuals could be correctly assigned to their parental population based on morphology alone. Finally, we discuss the biogeographic and conservation implications of these findings.

Genetic Causes of Syndromic and Non-Syndromic Autism

Science.gov (United States)

Caglayan, Ahmet O.

2010-01-01

Aims: Over the past decade, genetic tests have become available for numerous heritable disorders, especially those whose inheritance follows the Mendelian model. Autism spectrum disorders (ASDs) represent a group of developmental disorders with a strong genetic basis. During the past few years, genetic research in ASDs has been successful in…

Genetic parameters in a Swine Population

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Dana Popa

2010-05-01

Full Text Available The estimation of the variance-covariance components is a very important step in animal breeding because these components are necessary for: estimation of the genetic parameters, prediction of the breeding value and design of animal breeding programs. The estimation of genetic parameters is the first step in the development of a swine breeding program, using artificial insemination. Various procedures exist for estimation of heritability. There are three major procedures used for estimating heritability: analysis of variance (ANOVA, parents-offspring regression and restricted maximum likelihood (REML. By using ANOVA methodology or regression method it is possible to obtain aberrant values of genetic parameters (negative or over unit value of heritability coefficient, for example which can not be interpreting because is out of biological limits.

Genetic variability, correlation and path coefficients of yield and its components analysis in pumpkin (Cucurbita moschata Duch Ex Poir

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GM Mohsin

2017-06-01

Full Text Available Genetic variability, correlation and path coefficient were studied for yield and yield component traits in twenty one diverse genotypes of pumpkin. Highest genotypic coefficient of variation was recorded for fruit length (cm, single fruit weight (kg, Brix (% and yield per plant (kg. Heritability estimates in broad sense were higher for almost all the characters. The characters namely, fruit length, single fruit weight, yield per plant and brix% had high genotypic coefficient of variation coupled with heritability gave high genetic advance expressed as percentage of mean ranged from 76.84 to 96.06 which indicated that these characters were less influenced by environment confirming additive gene action, and therefore, selection of these characters would be more effective for yield improvement of pumpkins. Total six traits likely fruit length, fruit diameter, flesh thickness, single fruit weight and number of fruits per plant were positively and significantly associated with yield per plant. Path coefficient analysis also revealed maximum contribution of single fruit weight (0.869 to yield and this was followed by the contribution of number of fruit per plant (0.527 at genotypic level.

Expansion Under Climate Change: The Genetic Consequences.

Science.gov (United States)

Garnier, Jimmy; Lewis, Mark A

2016-11-01

Range expansion and range shifts are crucial population responses to climate change. Genetic consequences are not well understood but are clearly coupled to ecological dynamics that, in turn, are driven by shifting climate conditions. We model a population with a deterministic reaction-diffusion model coupled to a heterogeneous environment that develops in time due to climate change. We decompose the resulting travelling wave solution into neutral genetic components to analyse the spatio-temporal dynamics of its genetic structure. Our analysis shows that range expansions and range shifts under slow climate change preserve genetic diversity. This is because slow climate change creates range boundaries that promote spatial mixing of genetic components. Mathematically, the mixing leads to so-called pushed travelling wave solutions. This mixing phenomenon is not seen in spatially homogeneous environments, where range expansion reduces genetic diversity through gene surfing arising from pulled travelling wave solutions. However, the preservation of diversity is diminished when climate change occurs too quickly. Using diversity indices, we show that fast expansions and range shifts erode genetic diversity more than slow range expansions and range shifts. Our study provides analytical insight into the dynamics of travelling wave solutions in heterogeneous environments.

Genetic parameters, phenotypic, genotypic and environmental correlations and genetic variability on sunflower in the Brazilian Savannah

Directory of Open Access Journals (Sweden)

Ellen Grippi Lira

Full Text Available ABSTRACT: Sunflower (Helianthus annuus L. is an annual crop that stands out for its production of high quality oil and for an efficient selection, being necessary to estimate the components of genetic and phenotypic variance. This study aimed to estimate genetic parameters, phenotypic, genotypic and environmental correlations and genetic variability on sunflower in the Brazilian Savannah, evaluating the characters grain yield (YIELD, days to start flowering (DFL based on flowering date in R5, chapter length (CL, weight of a thousand achenes (WTA, plant height (H and oil content (OilC of 16 sunflower genotypes. The experiment was conducted at Embrapa Cerrados, Planaltina, DF, situated at 15º 35’ 30”S latitude, 47º 42’ 30”W longitude and 1.007m above sea level, in soil classified as dystroferric Oxisol. The experimental design used was a complete randomized block with four replicates. The nature for the effects of genotypes and blocks was fixed. Except for the character chapter length, genetic variance was the main component of the phenotypic variance among the genotypes, indicating high genetic variability and experimental efficiency with proper environmental control. In absolute terms, the genetic correlations were superior to phenotypic and environmental. The high values reported for heritability and selective accuracy indicated efficiency of phenotypic selection. Results showed high genetic variability among genotypes, which may contribute to the genetic improvement of sunflower.

The Association of Arsenic Exposure and Arsenic Metabolism with the Metabolic Syndrome and its Individual Components: Prospective Evidence from the Strong Heart Family Study.

Science.gov (United States)

Spratlen, Miranda J; Grau-Perez, Maria; Best, Lyle G; Yracheta, Joseph; Lazo, Mariana; Vaidya, Dhananjay; Balakrishnan, Poojitha; Gamble, Mary V; Francesconi, Kevin A; Goessler, Walter; Cole, Shelley A; Umans, Jason G; Howard, Barbara V; Navas-Acien, Ana

2018-03-15

Inorganic arsenic exposure is ubiquitous and both exposure and inter-individual differences in its metabolism have been associated with cardiometabolic risk. The association between arsenic exposure and arsenic metabolism with metabolic syndrome and its individual components, however, is relatively unknown. We used poisson regression with robust variance to evaluate the association between baseline arsenic exposure (urine arsenic levels) and metabolism (relative percentage of arsenic species over their sum) with incident metabolic syndrome and its individual components (elevated waist circumference, elevated triglycerides, reduced HDL, hypertension, elevated fasting plasma glucose) in 1,047 participants from the Strong Heart Family Study, a prospective family-based cohort in American Indian communities (baseline visits in 1998-1999 and 2001-2003, follow-up visits in 2001-2003 and 2006-2009). 32% of participants developed metabolic syndrome over follow-up. An IQR increase in arsenic exposure was associated with 1.19 (95% CI: 1.01, 1.41) greater risk for elevated fasting plasma glucose but not with other individual components or overall metabolic syndrome. Arsenic metabolism, specifically lower MMA% and higher DMA% was associated with higher risk of overall metabolic syndrome and elevated waist circumference, but not with any other component. These findings support there is a contrasting and independent association between arsenic exposure and arsenic metabolism with metabolic outcomes which may contribute to overall diabetes risk.

Radial Distribution Functions of Strongly Coupled Two-Temperature Plasmas

Science.gov (United States)

Shaffer, Nathaniel R.; Tiwari, Sanat Kumar; Baalrud, Scott D.

2017-10-01

We present tests of three theoretical models for the radial distribution functions (RDFs) in two-temperature strongly coupled plasmas. RDFs are useful in extending plasma thermodynamics and kinetic theory to strong coupling, but they are usually known only for thermal equilibrium or for approximate one-component model plasmas. Accurate two-component modeling is necessary to understand the impact of strong coupling on inter-species transport, e.g., ambipolar diffusion and electron-ion temperature relaxation. We demonstrate that the Seuferling-Vogel-Toeppfer (SVT) extension of the hypernetted chain equations not only gives accurate RDFs (as compared with classical molecular dynamics simulations), but also has a simple connection with the Yukawa OCP model. This connection gives a practical means to recover the structure of the electron background from knowledge of the ion-ion RDF alone. Using the model RDFs in Effective Potential Theory, we report the first predictions of inter-species transport coefficients of strongly coupled plasmas far from equilibrium. This work is supported by NSF Grant No. PHY-1453736, AFSOR Award No. FA9550-16-1-0221, and used XSEDE computational resources.

Teachers' Conceptions About the Genetic Determinism of Human Behaviour: A Survey in 23 Countries

Science.gov (United States)

Castéra, Jérémy; Clément, Pierre

2014-02-01

This work analyses the answers to a questionnaire from 8,285 in-service and pre-service teachers from 23 countries, elaborated by the Biohead-Citizen research project, to investigate teachers' conceptions related to the genetic determinism of human behaviour. A principal components analysis is used to assess the main trends in all the interviewed teachers' conceptions. This illustrates that innatism is present in two distinct ways: in relation to individuals (e.g. genetic determinism to justify intellectual likeness between individuals such as twins) or in relation to groups of humans (e.g. genetic determinism to justify gender differences or the superiority of some human ethnic groups). A between-factor analysis discriminates between countries, showing very significant differences. There is more innatism among teachers' conceptions in African countries and Lebanon than in European countries, Brazil and Australia. Among the other controlled parameters, only two are significantly independent of the country: the level of training and the level of knowledge of biology. A co-inertia analysis shows a strong correlation between non-citizen attitudes towards and innatist conceptions of genetic determinism regarding human groups. We discuss these findings and their implications for education.

The genetic architecture of fitness in a seed beetle: assessing the potential for indirect genetic benefits of female choice

DEFF Research Database (Denmark)

Bilde, T.; Friberg, U.; Maklakov, A.A.

2008-01-01

variance in F1 productivity, but lower genetic variance in egg-to-adult survival, which was strongly influenced by maternal and paternal effects. Conclusion Our results show that, in order to gain a relevant understanding of the genetic architecture of fitness, measures of offspring fitness should...... is the genetic interaction between parental genomes, as indicated by large amounts of non-additive genetic variance (dominance and/or epistasis) for F1 productivity. We discuss the processes that may maintain additive and non-additive genetic variance for fitness and how these relate to indirect selection...

Cross-Disorder Genome-Wide Analyses Suggest a Complex Genetic Relationship Between Tourette Syndrome and Obsessive-Compulsive Disorder

Science.gov (United States)

Yu, Dongmei; Mathews, Carol A.; Scharf, Jeremiah M.; Neale, Benjamin M.; Davis, Lea K.; Gamazon, Eric R.; Derks, Eske M.; Evans, Patrick; Edlund, Christopher K.; Crane, Jacquelyn; Fagerness, Jesen A.; Osiecki, Lisa; Gallagher, Patience; Gerber, Gloria; Haddad, Stephen; Illmann, Cornelia; McGrath, Lauren M.; Mayerfeld, Catherine; Arepalli, Sampath; Barlassina, Cristina; Barr, Cathy L.; Bellodi, Laura; Benarroch, Fortu; Berrió, Gabriel Bedoya; Bienvenu, O. Joseph; Black, Donald; Bloch, Michael H.; Brentani, Helena; Bruun, Ruth D.; Budman, Cathy L.; Camarena, Beatriz; Campbell, Desmond D.; Cappi, Carolina; Cardona Silgado, Julio C.; Cavallini, Maria C.; Chavira, Denise A.; Chouinard, Sylvain; Cook, Edwin H.; Cookson, M. R.; Coric, Vladimir; Cullen, Bernadette; Cusi, Daniele; Delorme, Richard; Denys, Damiaan; Dion, Yves; Eapen, Valsama; Egberts, Karin; Falkai, Peter; Fernandez, Thomas; Fournier, Eduardo; Garrido, Helena; Geller, Daniel; Gilbert, Donald; Girard, Simon L.; Grabe, Hans J.; Grados, Marco A.; Greenberg, Benjamin D.; Gross-Tsur, Varda; Grünblatt, Edna; Hardy, John; Heiman, Gary A.; Hemmings, Sian M.J.; Herrera, Luis D.; Hezel, Dianne M.; Hoekstra, Pieter J.; Jankovic, Joseph; Kennedy, James L.; King, Robert A.; Konkashbaev, Anuar I.; Kremeyer, Barbara; Kurlan, Roger; Lanzagorta, Nuria; Leboyer, Marion; Leckman, James F.; Lennertz, Leonhard; Liu, Chunyu; Lochner, Christine; Lowe, Thomas L.; Lupoli, Sara; Macciardi, Fabio; Maier, Wolfgang; Manunta, Paolo; Marconi, Maurizio; McCracken, James T.; Mesa Restrepo, Sandra C.; Moessner, Rainald; Moorjani, Priya; Morgan, Jubel; Muller, Heike; Murphy, Dennis L.; Naarden, Allan L.; Ochoa, William Cornejo; Ophoff, Roel A.; Pakstis, Andrew J.; Pato, Michele T.; Pato, Carlos N.; Piacentini, John; Pittenger, Christopher; Pollak, Yehuda; Rauch, Scott L.; Renner, Tobias; Reus, Victor I.; Richter, Margaret A.; Riddle, Mark A.; Robertson, Mary M.; Romero, Roxana; Rosário, Maria C.; Rosenberg, David; Ruhrmann, Stephan; Sabatti, Chiara; Salvi, Erika; Sampaio, Aline S.; Samuels, Jack; Sandor, Paul; Service, Susan K.; Sheppard, Brooke; Singer, Harvey S.; Smit, Jan H.; Stein, Dan J.; Strengman, Eric; Tischfield, Jay A.; Turiel, Maurizio; Valencia Duarte, Ana V.; Vallada, Homero; Veenstra-VanderWeele, Jeremy; Walitza, Susanne; Walkup, John; Wang, Ying; Weale, Mike; Weiss, Robert; Wendland, Jens R.; Westenberg, Herman G.M.; Yao, Yin; Hounie, Ana G.; Miguel, Euripedes C.; Nicolini, Humberto; Wagner, Michael; Ruiz-Linares, Andres; Cath, Danielle C.; McMahon, William; Posthuma, Danielle; Oostra, Ben A.; Nestadt, Gerald; Rouleau, Guy A.; Purcell, Shaun; Jenike, Michael A.; Heutink, Peter; Hanna, Gregory L.; Conti, David V.; Arnold, Paul D.; Freimer, Nelson; Stewart, S. Evelyn; Knowles, James A.; Cox, Nancy J.; Pauls, David L.

2014-01-01

Obsessive-compulsive disorder (OCD) and Tourette Syndrome (TS) are highly heritable neurodevelopmental disorders that are thought to share genetic risk factors. However, the identification of definitive susceptibility genes for these etiologically complex disorders remains elusive. Here, we report a combined genome-wide association study (GWAS) of TS and OCD in 2723 cases (1310 with OCD, 834 with TS, 579 with OCD plus TS/chronic tics (CT)), 5667 ancestry-matched controls, and 290 OCD parent-child trios. Although no individual single nucleotide polymorphisms (SNPs) achieved genome-wide significance, the GWAS signals were enriched for SNPs strongly associated with variations in brain gene expression levels, i.e. expression quantitative loci (eQTLs), suggesting the presence of true functional variants that contribute to risk of these disorders. Polygenic score analyses identified a significant polygenic component for OCD (p=2×10−4), predicting 3.2% of the phenotypic variance in an independent data set. In contrast, TS had a smaller, non-significant polygenic component, predicting only 0.6% of the phenotypic variance (p=0.06). No significant polygenic signal was detected across the two disorders, although the sample is likely underpowered to detect a modest shared signal. Furthermore, the OCD polygenic signal was significantly attenuated when cases with both OCD and TS/CT were included in the analysis (p=0.01). Previous work has shown that TS and OCD have some degree of shared genetic variation. However, the data from this study suggest that there are also distinct components to the genetic architectures of TS and OCD. Furthermore, OCD with co-occurring TS/CT may have different underlying genetic susceptibility compared to OCD alone. PMID:25158072

Variance Components and Genetic Parameters for Milk Production and Lactation Pattern in an Ethiopian Multibreed Dairy Cattle Population

Directory of Open Access Journals (Sweden)

Gebregziabher Gebreyohannes

2013-09-01

Full Text Available The objective of this study was to estimate variance components and genetic parameters for lactation milk yield (LY, lactation length (LL, average milk yield per day (YD, initial milk yield (IY, peak milk yield (PY, days to peak (DP and parameters (ln(a and c of the modified incomplete gamma function (MIG in an Ethiopian multibreed dairy cattle population. The dataset was composed of 5,507 lactation records collected from 1,639 cows in three locations (Bako, Debre Zeit and Holetta in Ethiopia from 1977 to 2010. Parameters for MIG were obtained from regression analysis of monthly test-day milk data on days in milk. The cows were purebred (Bos indicus Boran (B and Horro (H and their crosses with different fractions of Friesian (F, Jersey (J and Simmental (S. There were 23 breed groups (B, H, and their crossbreds with F, J, and S in the population. Fixed and mixed models were used to analyse the data. The fixed model considered herd-year-season, parity and breed group as fixed effects, and residual as random. The single and two-traits mixed animal repeatability models, considered the fixed effects of herd-year-season and parity subclasses, breed as a function of cow H, F, J, and S breed fractions and general heterosis as a function of heterozygosity, and the random additive animal, permanent environment, and residual effects. For the analysis of LY, LL was added as a fixed covariate to all models. Variance components and genetic parameters were estimated using average information restricted maximum likelihood procedures. The results indicated that all traits were affected (p<0.001 by the considered fixed effects. High grade B×F cows (3/16B 13/16F had the highest least squares means (LSM for LY (2,490±178.9 kg, IY (10.5±0.8 kg, PY (12.7±0.9 kg, YD (7.6±0.55 kg and LL (361.4±31.2 d, while B cows had the lowest LSM values for these traits. The LSM of LY, IY, YD, and PY tended to increase from the first to the fifth parity. Single-trait analyses

Equilibrium statistical mechanics of strongly coupled plasmas by numerical simulation

International Nuclear Information System (INIS)

DeWitt, H.E.

1977-01-01

Numerical experiments using the Monte Carlo method have led to systematic and accurate results for the thermodynamic properties of strongly coupled one-component plasmas and mixtures of two nuclear components. These talks are intended to summarize the results of Monte Carlo simulations from Paris and from Livermore. Simple analytic expressions for the equation of state and other thermodynamic functions have been obtained in which there is a clear distinction between a lattice-like static portion and a thermal portion. The thermal energy for the one-component plasma has a simple power dependence on temperature, (kT)/sup 3 / 4 /, that is identical to Monte Carlo results obtained for strongly coupled fluids governed by repulsive l/r/sup n/ potentials. For two-component plasmas the ion-sphere model is shown to accurately represent the static portion of the energy. Electron screening is included in the Monte Carlo simulations using linear response theory and the Lindhard dielectric function. Free energy expressions have been constructed for one and two component plasmas that allow easy computation of all thermodynamic functions

Cross-disorder genome-wide analyses suggest a complex genetic relationship between Tourette's syndrome and OCD.

Science.gov (United States)

Yu, Dongmei; Mathews, Carol A; Scharf, Jeremiah M; Neale, Benjamin M; Davis, Lea K; Gamazon, Eric R; Derks, Eske M; Evans, Patrick; Edlund, Christopher K; Crane, Jacquelyn; Fagerness, Jesen A; Osiecki, Lisa; Gallagher, Patience; Gerber, Gloria; Haddad, Stephen; Illmann, Cornelia; McGrath, Lauren M; Mayerfeld, Catherine; Arepalli, Sampath; Barlassina, Cristina; Barr, Cathy L; Bellodi, Laura; Benarroch, Fortu; Berrió, Gabriel Bedoya; Bienvenu, O Joseph; Black, Donald W; Bloch, Michael H; Brentani, Helena; Bruun, Ruth D; Budman, Cathy L; Camarena, Beatriz; Campbell, Desmond D; Cappi, Carolina; Silgado, Julio C Cardona; Cavallini, Maria C; Chavira, Denise A; Chouinard, Sylvain; Cook, Edwin H; Cookson, M R; Coric, Vladimir; Cullen, Bernadette; Cusi, Daniele; Delorme, Richard; Denys, Damiaan; Dion, Yves; Eapen, Valsama; Egberts, Karin; Falkai, Peter; Fernandez, Thomas; Fournier, Eduardo; Garrido, Helena; Geller, Daniel; Gilbert, Donald L; Girard, Simon L; Grabe, Hans J; Grados, Marco A; Greenberg, Benjamin D; Gross-Tsur, Varda; Grünblatt, Edna; Hardy, John; Heiman, Gary A; Hemmings, Sian M J; Herrera, Luis D; Hezel, Dianne M; Hoekstra, Pieter J; Jankovic, Joseph; Kennedy, James L; King, Robert A; Konkashbaev, Anuar I; Kremeyer, Barbara; Kurlan, Roger; Lanzagorta, Nuria; Leboyer, Marion; Leckman, James F; Lennertz, Leonhard; Liu, Chunyu; Lochner, Christine; Lowe, Thomas L; Lupoli, Sara; Macciardi, Fabio; Maier, Wolfgang; Manunta, Paolo; Marconi, Maurizio; McCracken, James T; Mesa Restrepo, Sandra C; Moessner, Rainald; Moorjani, Priya; Morgan, Jubel; Muller, Heike; Murphy, Dennis L; Naarden, Allan L; Nurmi, Erika; Ochoa, William Cornejo; Ophoff, Roel A; Pakstis, Andrew J; Pato, Michele T; Pato, Carlos N; Piacentini, John; Pittenger, Christopher; Pollak, Yehuda; Rauch, Scott L; Renner, Tobias; Reus, Victor I; Richter, Margaret A; Riddle, Mark A; Robertson, Mary M; Romero, Roxana; Rosário, Maria C; Rosenberg, David; Ruhrmann, Stephan; Sabatti, Chiara; Salvi, Erika; Sampaio, Aline S; Samuels, Jack; Sandor, Paul; Service, Susan K; Sheppard, Brooke; Singer, Harvey S; Smit, Jan H; Stein, Dan J; Strengman, Eric; Tischfield, Jay A; Turiel, Maurizio; Valencia Duarte, Ana V; Vallada, Homero; Veenstra-VanderWeele, Jeremy; Walitza, Susanne; Wang, Ying; Weale, Mike; Weiss, Robert; Wendland, Jens R; Westenberg, Herman G M; Shugart, Yin Yao; Hounie, Ana G; Miguel, Euripedes C; Nicolini, Humberto; Wagner, Michael; Ruiz-Linares, Andres; Cath, Danielle C; McMahon, William; Posthuma, Danielle; Oostra, Ben A; Nestadt, Gerald; Rouleau, Guy A; Purcell, Shaun; Jenike, Michael A; Heutink, Peter; Hanna, Gregory L; Conti, David V; Arnold, Paul D; Freimer, Nelson B; Stewart, S Evelyn; Knowles, James A; Cox, Nancy J; Pauls, David L

2015-01-01

Obsessive-compulsive disorder (OCD) and Tourette's syndrome are highly heritable neurodevelopmental disorders that are thought to share genetic risk factors. However, the identification of definitive susceptibility genes for these etiologically complex disorders remains elusive. The authors report a combined genome-wide association study (GWAS) of Tourette's syndrome and OCD. The authors conducted a GWAS in 2,723 cases (1,310 with OCD, 834 with Tourette's syndrome, 579 with OCD plus Tourette's syndrome/chronic tics), 5,667 ancestry-matched controls, and 290 OCD parent-child trios. GWAS summary statistics were examined for enrichment of functional variants associated with gene expression levels in brain regions. Polygenic score analyses were conducted to investigate the genetic architecture within and across the two disorders. Although no individual single-nucleotide polymorphisms (SNPs) achieved genome-wide significance, the GWAS signals were enriched for SNPs strongly associated with variations in brain gene expression levels (expression quantitative loci, or eQTLs), suggesting the presence of true functional variants that contribute to risk of these disorders. Polygenic score analyses identified a significant polygenic component for OCD (p=2×10(-4)), predicting 3.2% of the phenotypic variance in an independent data set. In contrast, Tourette's syndrome had a smaller, nonsignificant polygenic component, predicting only 0.6% of the phenotypic variance (p=0.06). No significant polygenic signal was detected across the two disorders, although the sample is likely underpowered to detect a modest shared signal. Furthermore, the OCD polygenic signal was significantly attenuated when cases with both OCD and co-occurring Tourette's syndrome/chronic tics were included in the analysis (p=0.01). Previous work has shown that Tourette's syndrome and OCD have some degree of shared genetic variation. However, the data from this study suggest that there are also distinct

Estimates of variance components for postweaning feed intake and ...

African Journals Online (AJOL)

Feed efficiency is of major economic importance in beef production. The objective of this work was to evaluate alternative measures of feed efficiency for use in genetic evaluation. To meet this objective, genetic parameters were estimated for the components of efficiency. These parameters were then used in multiple-trait ...

Crystal Genetics, Inc.

Science.gov (United States)

Kermani, Bahram G

2016-07-01

Crystal Genetics, Inc. is an early-stage genetic test company, focused on achieving the highest possible clinical-grade accuracy and comprehensiveness for detecting germline (e.g., in hereditary cancer) and somatic (e.g., in early cancer detection) mutations. Crystal's mission is to significantly improve the health status of the population, by providing high accuracy, comprehensive, flexible and affordable genetic tests, primarily in cancer. Crystal's philosophy is that when it comes to detecting mutations that are strongly correlated with life-threatening diseases, the detection accuracy of every single mutation counts: a single false-positive error could cause severe anxiety for the patient. And, more importantly, a single false-negative error could potentially cost the patient's life. Crystal's objective is to eliminate both of these error types.

Genetic basis of a cognitive complexity metric.

Directory of Open Access Journals (Sweden)

Narelle K Hansell

Full Text Available Relational complexity (RC is a metric reflecting capacity limitation in relational processing. It plays a crucial role in higher cognitive processes and is an endophenotype for several disorders. However, the genetic underpinnings of complex relational processing have not been investigated. Using the classical twin model, we estimated the heritability of RC and genetic overlap with intelligence (IQ, reasoning, and working memory in a twin and sibling sample aged 15-29 years (N = 787. Further, in an exploratory search for genetic loci contributing to RC, we examined associated genetic markers and genes in our Discovery sample and selected loci for replication in four independent samples (ALSPAC, LBC1936, NTR, NCNG, followed by meta-analysis (N>6500 at the single marker level. Twin modelling showed RC is highly heritable (67%, has considerable genetic overlap with IQ (59%, and is a major component of genetic covariation between reasoning and working memory (72%. At the molecular level, we found preliminary support for four single-marker loci (one in the gene DGKB, and at a gene-based level for the NPS gene, having influence on cognition. These results indicate that genetic sources influencing relational processing are a key component of the genetic architecture of broader cognitive abilities. Further, they suggest a genetic cascade, whereby genetic factors influencing capacity limitation in relational processing have a flow-on effect to more complex cognitive traits, including reasoning and working memory, and ultimately, IQ.

[Genetics factors in pathogenesis and clinical genetics of binge eating disorder].

Science.gov (United States)

Kibitov, А О; Мazo, G E

2016-01-01

Genetic studies have shown that binge eating disorder (ВЕD) aggregates in families, heritability was estimated as about 60% and additive genetic influences on BED up to 50%. Using a genetic approach has proved useful for verifying the diagnostic categories of BED using DSM-IV criteria and supporting the validity of considering this pathology as a separate nosological category. The results confirmed the genetic and pathogenic originality of BED as a separate psychopathological phenomenon, but not a subtype of obesity. It seems fruitful to considerate BED as a disease with hereditary predisposition with significant genetic influence and a complex psychopathological syndrome, including not only eating disorders, but also depressive and addictive component. A possible mechanism of pathogenesis of BED may be the interaction of the neuroendocrine and neurotransmitters systems including the active involvement of the reward system in response to a variety of chronic stress influences with the important modulatory role of specific personality traits. The high level of genetic influence on the certain clinical manifestations of BED confirms the ability to identify the subphenotypes of BED on genetic basis involving clinical criteria. It can not only contribute to further genetic studies, taking into account more homogeneous samples, but also help in finding differentiated therapeutic approaches.

Genetics of complex diseases

DEFF Research Database (Denmark)

Mellerup, Erling; Møller, Gert Lykke; Koefoed, Pernille

2012-01-01

A complex disease with an inheritable component is polygenic, meaning that several different changes in DNA are the genetic basis for the disease. Such a disease may also be genetically heterogeneous, meaning that independent changes in DNA, i.e. various genotypes, can be the genetic basis...... for the disease. Each of these genotypes may be characterized by specific combinations of key genetic changes. It is suggested that even if all key changes are found in genes related to the biology of a certain disease, the number of combinations may be so large that the number of different genotypes may be close...... to the number of patients suffering from the disease. This hypothesis is based on a study of bipolar disorder....

LDA+DMFT Approach to Magnetocrystalline Anisotropy of Strong Magnets

Directory of Open Access Journals (Sweden)

Jian-Xin Zhu

2014-05-01

Full Text Available The new challenges posed by the need of finding strong rare-earth-free magnets demand methods that can predict magnetization and magnetocrystalline anisotropy energy (MAE. We argue that correlated electron effects, which are normally underestimated in band-structure calculations, play a crucial role in the development of the orbital component of the magnetic moments. Because magnetic anisotropy arises from this orbital component, the ability to include correlation effects has profound consequences on our predictive power of the MAE of strong magnets. Here, we show that incorporating the local effects of electronic correlations with dynamical mean-field theory provides reliable estimates of the orbital moment, the mass enhancement, and the MAE of YCo_{5}.

Early Components of the Complement Classical Activation Pathway in Human Systemic Autoimmune Diseases

Science.gov (United States)

Lintner, Katherine E.; Wu, Yee Ling; Yang, Yan; Spencer, Charles H.; Hauptmann, Georges; Hebert, Lee A.; Atkinson, John P.; Yu, C. Yung

2016-01-01

The complement system consists of effector proteins, regulators, and receptors that participate in host defense against pathogens. Activation of the complement system, via the classical pathway (CP), has long been recognized in immune complex-mediated tissue injury, most notably systemic lupus erythematosus (SLE). Paradoxically, a complete deficiency of an early component of the CP, as evidenced by homozygous genetic deficiencies reported in human, are strongly associated with the risk of developing SLE or a lupus-like disease. Similarly, isotype deficiency attributable to a gene copy-number (GCN) variation and/or the presence of autoantibodies directed against a CP component or a regulatory protein that result in an acquired deficiency are relatively common in SLE patients. Applying accurate assay methodologies with rigorous data validations, low GCNs of total C4, and heterozygous and homozygous deficiencies of C4A have been shown as medium to large effect size risk factors, while high copy numbers of total C4 or C4A as prevalent protective factors, of European and East-Asian SLE. Here, we summarize the current knowledge related to genetic deficiency and insufficiency, and acquired protein deficiencies for C1q, C1r, C1s, C4A/C4B, and C2 in disease pathogenesis and prognosis of SLE, and, briefly, for other systemic autoimmune diseases. As the complement system is increasingly found to be associated with autoimmune diseases and immune-mediated diseases, it has become an attractive therapeutic target. We highlight the recent developments and offer a balanced perspective concerning future investigations and therapeutic applications with a focus on early components of the CP in human systemic autoimmune diseases. PMID:26913032

Genomic patterns in Acropora cervicornis show extensive population structure and variable genetic diversity.

Science.gov (United States)

Drury, Crawford; Schopmeyer, Stephanie; Goergen, Elizabeth; Bartels, Erich; Nedimyer, Ken; Johnson, Meaghan; Maxwell, Kerry; Galvan, Victor; Manfrino, Carrie; Lirman, Diego

2017-08-01

Threatened Caribbean coral communities can benefit from high-resolution genetic data used to inform management and conservation action. We use Genotyping by Sequencing (GBS) to investigate genetic patterns in the threatened coral, Acropora cervicornis , across the Florida Reef Tract (FRT) and the western Caribbean. Results show extensive population structure at regional scales and resolve previously unknown structure within the FRT. Different regions also exhibit up to threefold differences in genetic diversity (He), suggesting targeted management based on the goals and resources of each population is needed. Patterns of genetic diversity have a strong spatial component, and our results show Broward and the Lower Keys are among the most diverse populations in Florida. The genetic diversity of Caribbean staghorn coral is concentrated within populations and within individual reefs (AMOVA), highlighting the complex mosaic of population structure. This variance structure is similar over regional and local scales, which suggests that in situ nurseries are adequately capturing natural patterns of diversity, representing a resource that can replicate the average diversity of wild assemblages, serving to increase intraspecific diversity and potentially leading to improved biodiversity and ecosystem function. Results presented here can be translated into specific goals for the recovery of A. cervicornis , including active focus on low diversity areas, protection of high diversity and connectivity, and practical thresholds for responsible restoration.

An experimental study of strong reciprocity in bacteria.

Science.gov (United States)

Inglis, R Fredrik; West, Stuart; Buckling, Angus

2014-02-01

Strong reciprocity, whereby cooperators punish non-cooperators, may help to explain the evolutionary success of cooperative behaviours. However, theory suggests that selection for strong reciprocity can depend upon tight genetic linkage between cooperation and punishment, to avoid the strategy being outcompeted by non-punishing cooperators. We tested this hypothesis using experimental populations of the bacterium Pseudomonas aeruginosa, which cooperate by producing iron-scavenging siderophores and, in this context, punish non-cooperators with toxins. Consistent with theory, we show that cooperative punishers can indeed invade cheats, but only when the traits are tightly linked. These results emphasize that punishment is only likely to be favoured when the punishment itself leads to a direct or indirect fitness benefit to the actor.

Component Structure of Individual Differences in True and False Recognition of Faces

Science.gov (United States)

Bartlett, James C.; Shastri, Kalyan K.; Abdi, Herve; Neville-Smith, Marsha

2009-01-01

Principal-component analyses of 4 face-recognition studies uncovered 2 independent components. The first component was strongly related to false-alarm errors with new faces as well as to facial "conjunctions" that recombine features of previously studied faces. The second component was strongly related to hits as well as to the conjunction/new…

A parallel attractor-finding algorithm based on Boolean satisfiability for genetic regulatory networks.

Directory of Open Access Journals (Sweden)

Wensheng Guo

Full Text Available In biological systems, the dynamic analysis method has gained increasing attention in the past decade. The Boolean network is the most common model of a genetic regulatory network. The interactions of activation and inhibition in the genetic regulatory network are modeled as a set of functions of the Boolean network, while the state transitions in the Boolean network reflect the dynamic property of a genetic regulatory network. A difficult problem for state transition analysis is the finding of attractors. In this paper, we modeled the genetic regulatory network as a Boolean network and proposed a solving algorithm to tackle the attractor finding problem. In the proposed algorithm, we partitioned the Boolean network into several blocks consisting of the strongly connected components according to their gradients, and defined the connection between blocks as decision node. Based on the solutions calculated on the decision nodes and using a satisfiability solving algorithm, we identified the attractors in the state transition graph of each block. The proposed algorithm is benchmarked on a variety of genetic regulatory networks. Compared with existing algorithms, it achieved similar performance on small test cases, and outperformed it on larger and more complex ones, which happens to be the trend of the modern genetic regulatory network. Furthermore, while the existing satisfiability-based algorithms cannot be parallelized due to their inherent algorithm design, the proposed algorithm exhibits a good scalability on parallel computing architectures.

Genetic determinants of circulating sphingolipid concentrations in European populations.

Directory of Open Access Journals (Sweden)

Andrew A Hicks

2009-10-01

Full Text Available Sphingolipids have essential roles as structural components of cell membranes and in cell signalling, and disruption of their metabolism causes several diseases, with diverse neurological, psychiatric, and metabolic consequences. Increasingly, variants within a few of the genes that encode enzymes involved in sphingolipid metabolism are being associated with complex disease phenotypes. Direct experimental evidence supports a role of specific sphingolipid species in several common complex chronic disease processes including atherosclerotic plaque formation, myocardial infarction (MI, cardiomyopathy, pancreatic beta-cell failure, insulin resistance, and type 2 diabetes mellitus. Therefore, sphingolipids represent novel and important intermediate phenotypes for genetic analysis, yet little is known about the major genetic variants that influence their circulating levels in the general population. We performed a genome-wide association study (GWAS between 318,237 single-nucleotide polymorphisms (SNPs and levels of circulating sphingomyelin (SM, dihydrosphingomyelin (Dih-SM, ceramide (Cer, and glucosylceramide (GluCer single lipid species (33 traits; and 43 matched metabolite ratios measured in 4,400 subjects from five diverse European populations. Associated variants (32 in five genomic regions were identified with genome-wide significant corrected p-values ranging down to 9.08x10(-66. The strongest associations were observed in or near 7 genes functionally involved in ceramide biosynthesis and trafficking: SPTLC3, LASS4, SGPP1, ATP10D, and FADS1-3. Variants in 3 loci (ATP10D, FADS3, and SPTLC3 associate with MI in a series of three German MI studies. An additional 70 variants across 23 candidate genes involved in sphingolipid-metabolizing pathways also demonstrate association (p = 10(-4 or less. Circulating concentrations of several key components in sphingolipid metabolism are thus under strong genetic control, and variants in these loci can be

A Neolithic expansion, but strong genetic structure, in the independent history of New Guinea.

Science.gov (United States)

Bergström, Anders; Oppenheimer, Stephen J; Mentzer, Alexander J; Auckland, Kathryn; Robson, Kathryn; Attenborough, Robert; Alpers, Michael P; Koki, George; Pomat, William; Siba, Peter; Xue, Yali; Sandhu, Manjinder S; Tyler-Smith, Chris

2017-09-15

New Guinea shows human occupation since ~50 thousand years ago (ka), independent adoption of plant cultivation ~10 ka, and great cultural and linguistic diversity today. We performed genome-wide single-nucleotide polymorphism genotyping on 381 individuals from 85 language groups in Papua New Guinea and find a sharp divide originating 10 to 20 ka between lowland and highland groups and a lack of non-New Guinean admixture in the latter. All highlanders share ancestry within the last 10 thousand years, with major population growth in the same period, suggesting population structure was reshaped following the Neolithic lifestyle transition. However, genetic differentiation between groups in Papua New Guinea is much stronger than in comparable regions in Eurasia, demonstrating that such a transition does not necessarily limit the genetic and linguistic diversity of human societies. Copyright © 2017, American Association for the Advancement of Science.

Constant, cycling, hot and cold thermal environments: strong effects on mean viability but not on genetic estimates

DEFF Research Database (Denmark)

Ketola, Tarmo; Kellermann, Vanessa; Kristensen, Torsten Nygård

2012-01-01

and their fluctuations. How species will respond to these changes is uncertain, particularly as there is a lack of studies which compare genetic performances in constant vs. fluctuating environments. In this study, we used a nested full-sib/half-sib breeding design to examine how the genetic variances and heritabilities...

Melanoma genetics

DEFF Research Database (Denmark)

Read, Jazlyn; Wadt, Karin A W; Hayward, Nicholas K

2015-01-01

Approximately 10% of melanoma cases report a relative affected with melanoma, and a positive family history is associated with an increased risk of developing melanoma. Although the majority of genetic alterations associated with melanoma development are somatic, the underlying presence of herita......Approximately 10% of melanoma cases report a relative affected with melanoma, and a positive family history is associated with an increased risk of developing melanoma. Although the majority of genetic alterations associated with melanoma development are somatic, the underlying presence...... in a combined total of approximately 50% of familial melanoma cases, the underlying genetic basis is unexplained for the remainder of high-density melanoma families. Aside from the possibility of extremely rare mutations in a few additional high penetrance genes yet to be discovered, this suggests a likely...... polygenic component to susceptibility, and a unique level of personal melanoma risk influenced by multiple low-risk alleles and genetic modifiers. In addition to conferring a risk of cutaneous melanoma, some 'melanoma' predisposition genes have been linked to other cancers, with cancer clustering observed...

Genetic Counseling and Evaluation for BRCA1/2 Testing

Science.gov (United States)

... Options Talking to Family Family Stories Diseases Genetic Counseling for Hereditary Breast and Ovarian Cancer Recommend on ... mutation, your doctor may refer you for genetic counseling. Understanding and dealing with a strong family health ...

Ontogeny of additive and maternal genetic effects: lessons from domestic mammals.

Science.gov (United States)

Wilson, Alastair J; Reale, Denis

2006-01-01

Evolution of size and growth depends on heritable variation arising from additive and maternal genetic effects. Levels of heritable (and nonheritable) variation might change over ontogeny, increasing through "variance compounding" or decreasing through "compensatory growth." We test for these processes using a meta-analysis of age-specific weight traits in domestic ungulates. Generally, mean standardized variance components decrease with age, consistent with compensatory growth. Phenotypic convergence among adult sheep occurs through decreasing environmental and maternal genetic variation. Maternal variation similarly declines in cattle. Maternal genetic effects are thus reduced with age (both in absolute and relative terms). Significant trends in heritability (decreasing in cattle, increasing in sheep) result from declining maternal and environmental components rather than from changing additive variation. There was no evidence for increasing standardized variance components. Any compounding must therefore be masked by more important compensatory processes. While extrapolation of these patterns to processes in natural population is difficult, our results highlight the inadequacy of assuming constancy in genetic parameters over ontogeny. Negative covariance between direct and maternal genetic effects was common. Negative correlations with additive and maternal genetic variances indicate that antagonistic pleiotropy (between additive and maternal genetic effects) may maintain genetic variance and limit responses to selection.

Genetic influence on prolonged gestation

DEFF Research Database (Denmark)

Laursen, Maja; Bille, Camilla; Olesen, Annette Wind

2004-01-01

OBJECTIVE: The purpose of this study was to test a possible genetic component to prolonged gestation. STUDY DESIGN: The gestational duration of single, first pregnancies by both female and male twins was obtained by linking the Danish Twin Registry, The Danish Civil Registration System, and the D...... factors. CONCLUSION: Maternal genes influence prolonged gestation. However, a substantial paternal genetic influence through the fetus was not found....

Effects of functionally asexual reproduction on quantitative genetic variation in the evening primroses (Oenothera, Onagraceae).

Science.gov (United States)

Godfrey, Ryan M; Johnson, Marc T J

2014-11-01

It has long been predicted that a loss of sexual reproduction leads to decreased heritable variation within populations and increased differentiation between populations. Despite an abundance of theory, there are few empirical tests of how sex affects genetic variation in phenotypic traits, especially for plants. Here we test whether repeated losses of two critical components of sex (recombination and segregation) in the evening primroses (Oenothera L., Onagraceae) affect quantitative genetic variation within and between populations. We sampled multiple genetic families from 3-5 populations from each of eight Oenothera species, which represented four independent transitions between sexual reproduction and a functionally asexual genetic system called "permanent translocation heterozygosity." We used quantitative genetics methods to partition genetic variation within and between populations for eight plant traits related to growth, leaf physiology, flowering, and resistance to herbivores. Heritability was, on average, 74% higher in sexual Oenothera populations than in functionally asexual populations, with plant growth rate, specific leaf area, and the percentage of leaf water content showing the strongest differences. By contrast, genetic differentiation among populations was 2.8× higher in functionally asexual vs. sexual Oenothera species. This difference was particularly strong for specific leaf area. Sexual populations tended to exhibit higher genetic correlations among traits, but this difference was weakly supported. These results support the prediction that sexual reproduction maintains higher genetic variation within populations, which may facilitate adaptive evolution. We also found partial support for the prediction that a loss of sex leads to greater population differentiation, which may elevate speciation rates. © 2014 Botanical Society of America, Inc.

The genetic basis of music ability

Science.gov (United States)

Tan, Yi Ting; McPherson, Gary E.; Peretz, Isabelle; Berkovic, Samuel F.; Wilson, Sarah J.

2014-01-01

Music is an integral part of the cultural heritage of all known human societies, with the capacity for music perception and production present in most people. Researchers generally agree that both genetic and environmental factors contribute to the broader realization of music ability, with the degree of music aptitude varying, not only from individual to individual, but across various components of music ability within the same individual. While environmental factors influencing music development and expertise have been well investigated in the psychological and music literature, the interrogation of possible genetic influences has not progressed at the same rate. Recent advances in genetic research offer fertile ground for exploring the genetic basis of music ability. This paper begins with a brief overview of behavioral and molecular genetic approaches commonly used in human genetic analyses, and then critically reviews the key findings of genetic investigations of the components of music ability. Some promising and converging findings have emerged, with several loci on chromosome 4 implicated in singing and music perception, and certain loci on chromosome 8q implicated in absolute pitch and music perception. The gene AVPR1A on chromosome 12q has also been implicated in music perception, music memory, and music listening, whereas SLC6A4 on chromosome 17q has been associated with music memory and choir participation. Replication of these results in alternate populations and with larger samples is warranted to confirm the findings. Through increased research efforts, a clearer picture of the genetic mechanisms underpinning music ability will hopefully emerge. PMID:25018744

Global existence and blow-up phenomena for two-component Degasperis-Procesi system and two-component b-family system

OpenAIRE

Liu, Jingjing; Yin, Zhaoyang

2014-01-01

This paper is concerned with global existence and blow-up phenomena for two-component Degasperis-Procesi system and two-component b-family system. The strategy relies on our observation on new conservative quantities of these systems. Several new global existence results and a new blowup result of strong solutions to the two-component Degasperis- Procesi system and the two-component b-family system are presented by using these new conservative quantities.

Comparative analysis of genetic diversity and differentiation of cauliflower (Brassica oleracea var. botrytis accessions from two ex situ genebanks.

Directory of Open Access Journals (Sweden)

Eltohamy A A Yousef

Full Text Available Cauliflower (Brassica oleracea var. botrytis is an important vegetable crop for human nutrition. We characterized 192 cauliflower accessions from the USDA and IPK genebanks with genotyping by sequencing (GBS. They originated from 26 different countries and represent about 44% of all cauliflower accessions in both genebanks. The analysis of genetic diversity revealed that accessions formed two major groups that represented the two genebanks and were not related to the country of origin. This differentiation was robust with respect to the analysis methods that included principal component analysis, ADMIXTURE and neighbor-joining trees. Genetic diversity was higher in the USDA collection and significant phenotypic differences between the two genebanks were found in three out of six traits investigated. GBS data have a high proportion of missing data, but we observed that the exclusion of single nucleotide polymorphisms (SNPs with missing data or the imputation of missing SNP alleles produced very similar results. The results indicate that the composition and type of accessions have a strong effect on the structure of genetic diversity of ex situ collections, although regeneration procedures and local adaptation to regeneration conditions may also contribute to a divergence. Fst-based outlier tests of genetic differentiation identified only a small proportion (<1% of SNPs that are highly differentiated between the two genebanks, which indicates that selection during seed regeneration is not a major cause of differentiation between genebanks. Seed regeneration procedures of both genebanks do not result in different levels of genetic drift and loss of genetic variation. We therefore conclude that the composition and type of accessions mainly influence the level of genetic diversity and explain the strong genetic differentiation between the two ex situ collections. In summary, GBS is a useful method for characterizing genetic diversity in cauliflower

The 5-HT2A receptor binding pattern in the human brain is strongly genetically determined

DEFF Research Database (Denmark)

Pinborg, Lars H; Arfan, Haroon; Haugbol, Steven

2007-01-01

With the appropriate radiolabeled tracers, positron emission tomography (PET) enables in vivo human brain imaging of markers for neurotransmission, including neurotransmitter synthesis, receptors, and transporters. Whereas structural imaging studies have provided compelling evidence that the human...... brain anatomy is largely genetically determined, it is currently unknown to what degree neuromodulatory markers are subjected to genetic and environmental influence. Changes in serotonin 2A (5-HT(2A)) receptors have been reported to occur in various neuropsychiatric disorders and an association between...

Explosion source strong ground motions in the Mississippi embayment

Science.gov (United States)

Langston, C.A.; Bodin, P.; Powell, C.; Withers, M.; Horton, S.; Mooney, W.

2006-01-01

Two strong-motion arrays were deployed for the October 2002 Embayment Seismic Excitation Experiment to study the spatial variation of strong ground motions in the deep, unconsolidated sediments of the Mississippi embayment because there are no comparable strong-motion data from natural earthquakes in the area. Each linear array consisted of eight three-component K2 accelerographs spaced 15 m apart situated 1.2 and 2.5 kin from 2268-kg and 1134-kg borehole explosion sources, respectively. The array data show distinct body-wave and surface-wave arrivals that propagate within the thick, unconsolidated sedimentary column, the high-velocity basement rocks, and small-scale structure near the surface. Time-domain coherence of body-wave and surface-wave arrivals is computed for acceleration, velocity, and displacement time windows. Coherence is high for relatively low-frequency verticalcomponent Rayleigh waves and high-frequency P waves propagating across the array. Prominent high-frequency PS conversions seen on radial components, a proxy for the direct S wave from earthquake sources, lose coherence quickly over the 105-m length of the array. Transverse component signals are least coherent for any ground motion and appear to be highly scattered. Horizontal phase velocity is computed by using the ratio of particle velocity to estimates of the strain based on a plane-wave-propagation model. The resulting time-dependent phase-velocity map is a useful way to infer the propagation mechanisms of individual seismic phases and time windows of three-component waveforms. Displacement gradient analysis is a complementary technique for processing general spatial-array data to obtain horizontal slowness information.

Genetic Parameters of Common Wheat in Nepal

OpenAIRE

Bal Krishna Joshi; Dhruba Bahadur Thapa; Madan Raj Bhatta

2015-01-01

Knowledge on variation within traits and their genetics are prerequisites in crop improvement program. Thus, in present paper we aimed to estimate genetic and environmental indices of common wheat genotypes. For the purpose, eight quantitative traits were measured from 30 wheat genotypes, which were in randomized complete block design with 3 replicates. Components of variance and covariance were estimated along with heritability, genetic gain, realized heritability, coheritability and correla...

Identification of genetic determinants of the sexual dimorphism in CNS autoimmunity.

Directory of Open Access Journals (Sweden)

Frank Bearoff

Full Text Available Multiple sclerosis (MS is a debilitating chronic inflammatory disease of the nervous system that affects approximately 2.3 million individuals worldwide, with higher prevalence in females, and a strong genetic component. While over 200 MS susceptibility loci have been identified in GWAS, the underlying mechanisms whereby they contribute to disease susceptibility remains ill-defined. Forward genetics approaches using conventional laboratory mouse strains are useful in identifying and functionally dissecting genes controlling disease-relevant phenotypes, but are hindered by the limited genetic diversity represented in such strains. To address this, we have combined the powerful chromosome substitution (consomic strain approach with the genetic diversity of a wild-derived inbred mouse strain. Using experimental allergic encephalomyelitis (EAE, a mouse model of MS, we evaluated genetic control of disease course among a panel of 26 consomic strains of mice inheriting chromosomes from the wild-derived PWD strain on the C57BL/6J background, which models the genetic diversity seen in human populations. Nineteen linkages on 18 chromosomes were found to harbor loci controlling EAE. Of these 19 linkages, six were male-specific, four were female-specific, and nine were non-sex-specific, consistent with a differential genetic control of disease course between males and females. An MS-GWAS candidate-driven bioinformatic analysis using orthologous genes linked to EAE course identified sex-specific and non-sex-specific gene networks underlying disease pathogenesis. An analysis of sex hormone regulation of genes within these networks identified several key molecules, prominently including the MAP kinase family, known hormone-dependent regulators of sex differences in EAE course. Importantly, our results provide the framework by which consomic mouse strains with overall genome-wide genetic diversity, approximating that seen in humans, can be used as a rapid and

Strong population structure but no equilibrium yet: Genetic connectivity and phylogeography in the kelp

NARCIS (Netherlands)

Luttikhuizen, P.C.; van den Heuvel, F.H.M.; Rebours, C.; Witte, H.J.; van Bleijswijk, J.D.L.; Timmermans, K.

2018-01-01

Kelp aquaculture is globally developing steadily as human food source, along with other applications. One of the newer crop species is Saccharina latissima, a northern hemisphere kelp inhabiting temperate to arctic rocky shores. To protect and document its natural genetic variation at the

Microallopatry caused strong diversification in Buthus scorpions (Scorpiones: Buthidae in the Atlas Mountains (NW Africa.

Directory of Open Access Journals (Sweden)

Jan C Habel

Full Text Available The immense biodiversity of the Atlas Mountains in North Africa might be the result of high rates of microallopatry caused by mountain barriers surpassing 4000 meters leading to patchy habitat distributions. We test the influence of geographic structures on the phylogenetic patterns among Buthus scorpions using mtDNA sequences. We sampled 91 individuals of the genus Buthus from 51 locations scattered around the Atlas Mountains (Antiatlas, High Atlas, Middle Atlas and Jebel Sahro. We sequenced 452 bp of the Cytochrome Oxidase I gene which proved to be highly variable within and among Buthus species. Our phylogenetic analysis yielded 12 distinct genetic groups one of which comprised three subgroups mostly in accordance with the orographic structure of the mountain systems. Main clades overlap with each other, while subclades are distributed parapatrically. Geographic structures likely acted as long-term barriers among populations causing restriction of gene flow and allowing for strong genetic differentiation. Thus, genetic structure and geographical distribution of genetic (subclusters follow the classical theory of allopatric differentiation where distinct groups evolve without range overlap until reproductive isolation and ecological differentiation has built up. Philopatry and low dispersal ability of Buthus scorpions are the likely causes for the observed strong genetic differentiation at this small geographic scale.

Three-dimensional electromagnetic strong turbulence. II. Wave packet collapse and structure of wave packets during strong turbulence

International Nuclear Information System (INIS)

Graham, D. B.; Robinson, P. A.; Cairns, Iver H.; Skjaeraasen, O.

2011-01-01

Large-scale simulations of wave packet collapse are performed by numerically solving the three-dimensional (3D) electromagnetic Zakharov equations, focusing on individual wave packet collapses and on wave packets that form in continuously driven strong turbulence. The collapse threshold is shown to decrease as the electron thermal speed ν e /c increases and as the temperature ratio T i /T e of ions to electrons decreases. Energy lost during wave packet collapse and dissipation is shown to depend on ν e /c. The dynamics of density perturbations after collapse are studied in 3D electromagnetic strong turbulence for a range of T i /T e . The structures of the Langmuir, transverse, and total electric field components of wave packets during strong turbulence are investigated over a range of ν e /c. For ν e /c e /c > or approx. 0.17, transverse modes become trapped in density wells and contribute significantly to the structure of the total electric field. At all ν e /c, the Langmuir energy density contours of wave packets are predominantly oblate (pancake shaped). The transverse energy density contours of wave packets are predominantly prolate (sausage shaped), with the major axis being perpendicular to the major axes of the Langmuir component. This results in the wave packet becoming more nearly spherical as ν e /c increases, and in turn generates more spherical density wells during collapse. The results obtained are compared with previous 3D electrostatic results and 2D electromagnetic results.

Derivation of the one component plasma fluid equation of state in strong coupling

International Nuclear Information System (INIS)

DeWitt, H.E.; Rosenfeld, Y.

1979-01-01

A variational calculation of the one component plasma energy using the hard sphere Percus-Yevick g(r) and the virial entropy gives U/NkT = a GAMMA + b GAMMAsup(1/4) + c + d/ GAMMAsup(1/4) + ... in agreement with the empirical fit to Monte Carlo data. (orig.)

Principal Component Analysis of Some Quantitative and Qualitative Traits in Iranian Spinach Landraces

Directory of Open Access Journals (Sweden)

Mohebodini Mehdi

2017-08-01

Full Text Available Landraces of spinach in Iran have not been sufficiently characterised for their morpho-agronomic traits. Such characterisation would be helpful in the development of new genetically improved cultivars. In this study 54 spinach accessions collected from the major spinach growing areas of Iran were evaluated to determine their phenotypic diversity profile of spinach genotypes on the basis of 10 quantitative and 9 qualitative morpho-agronomic traits. High coefficients of variation were recorded in some quantitative traits (dry yield and leaf area and all of the qualitative traits. Using principal component analysis, the first four principal components with eigen-values more than 1 contributed 87% of the variability among accessions for quantitative traits, whereas the first four principal components with eigen-values more than 0.8 contributed 79% of the variability among accessions for qualitative traits. The most important relations observed on the first two principal components were a strong positive association between leaf width and petiole length; between leaf length and leaf numbers in flowering; and among fresh yield, dry yield and petiole diameter; a near zero correlation between days to flowering with leaf width and petiole length. Prickly seeds, high percentage of female plants, smooth leaf texture, high numbers of leaves at flowering, greygreen leaves, erect petiole attitude and long petiole length are important characters for spinach breeding programmes.

Genetic variations in the serotoninergic system contribute to body-mass index in Chinese adolescents.

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Chunhui Chen

Full Text Available OBJECTIVE: Obesity has become a worldwide health problem in the past decades. Human and animal studies have implicated serotonin in appetite regulation, and behavior genetic studies have shown that body mass index (BMI has a strong genetic component. However, the roles of genes related to the serotoninergic (5-hydroxytryptamine,5-HT system in obesity/BMI are not well understood, especially in Chinese subjects. SUBJECTS AND DESIGN: With a sample of 478 healthy Chinese volunteers, this study investigated the relation between BMI and genetic variations of the serotoninergic system as characterized by 136 representative polymorphisms. We used a system-level approach to identify SNPs associated with BMI, then estimated their overall contribution to BMI by multiple regression and verified it by permutation. RESULTS: We identified 12 SNPs that made statistically significant contributions to BMI. After controlling for gender and age, four of these SNPs accounted for 7.7% additional variance of BMI. Permutation analysis showed that the probability of obtaining these findings by chance was low (p = 0.015, permuted for 1000 times. CONCLUSION: These results showed that genetic variations in the serotoninergic system made a moderate contribution to individual differences in BMI among a healthy Chinese sample, suggesting that a similar approach can be used to study obesity.

Genetic evaluations for growth heat tolerance in Angus cattle.

Science.gov (United States)

Bradford, H L; Fragomeni, B O; Bertrand, J K; Lourenco, D A L; Misztal, I

2016-10-01

The objectives were to assess the impact of heat stress and to develop a model for genetic evaluation of growth heat tolerance in Angus cattle. The American Angus Association provided weaning weight (WW) and yearling weight (YW) data, and records from the Upper South region were used because of the hot climatic conditions. Heat stress was characterized by a weaning (yearling) heat load function defined as the mean temperature-humidity index (THI) units greater than 75 (70) for 30 (150) d prior to the weigh date. Therefore, a weaning (yearling) heat load of 5 units corresponded to 80 (75) for the corresponding period prior to the weigh date. For all analyses, 82,669 WW and 69,040 YW were used with 3 ancestral generations in the pedigree. Univariate models were a proxy for the Angus growth evaluation, and reaction norms using 2 B-splines for heat load were fit separately for weaning and yearling heat loads. For both models, random effects included direct genetic, maternal genetic, maternal permanent environment (WW only), and residual. Fixed effects included a linear age covariate, age-of-dam class (WW only), and contemporary group for both models and fixed regressions on the B-splines in the reaction norm. Direct genetic correlations for WW were strong for modest heat load differences but decreased to less than 0.50 for large differences. Reranking of proven sires occurred for only WW direct effects for the reaction norms with extreme heat load differences. Conversely, YW results indicated little effect of heat stress on genetic merit. Therefore, weaning heat tolerance was a better candidate for developing selection tools. Maternal heritabilities were consistent across heat loads, and maternal genetic correlations were greater than 0.90 for nearly all heat load combinations. No evidence existed for a genotype × environment interaction for the maternal component of growth. Overall, some evidence exists for phenotypic plasticity for the direct genetic effects of WW

CYTOKINES GENETIC POLYMORPHISM: THE PAST AND THE FUTURE

Directory of Open Access Journals (Sweden)

L. V. Puzyryova

2016-01-01

Full Text Available The molecular genetics opens the new horizons in modern medicine, especially now when many diseases are given huge value in a type of their prevalence among various groups of population. Extremely high interleukin genes polymorphism degrees are studied well especially genetic polymorphism of tumor necrosis factor. Patients with HIV infection in the territory of Russia cause now the highest degree of mortality that is the most actual and socially significant problem of healthcare. This problems studying attracts many researchers. Works in respect of genetic immunity to a virus and influence of cytokines production on the disease forecast are especially interesting. One of the HIV replication influencing factors are cytokines, some of which, including the tumor necrosis factor and interleukin-6 can promote replication of HIV, raising an expression of virus regulatory genes. During disease progress in parallel of anti-inflammatory cytokines level increase (causing in this case rather ineffective antibodies level increase there is an T-helpers suppression stimulating a strong cellular component. Cytokine network functioning during HIV infection depends on many reasons which the individual variation in cytokine production caused by a number of genetic features, as well as an existence of opportunistic infection. Cytokines polymorphism determination in HIV infected patients is necessary in clinical practice for disease progression forecast to adverse fast transition to AIDS that it is important to consider in a choice of tactics of the supporting therapy of HIV-positive patients. Considering insufficient efficiency of modern methods of treatment, restoration and modulation of cytokines balance will increase anti-virus activity of immune system, influencing the factors blocking replication of a HIV.

Disentangling privacy from property: toward a deeper understanding of genetic privacy.

Science.gov (United States)

Suter, Sonia M

2004-04-01

With the mapping of the human genome, genetic privacy has become a concern to many. People care about genetic privacy because genes play an important role in shaping us--our genetic information is about us, and it is deeply connected to our sense of ourselves. In addition, unwanted disclosure of our genetic information, like a great deal of other personal information, makes us vulnerable to unwanted exposure, stigmatization, and discrimination. One recent approach to protecting genetic privacy is to create property rights in genetic information. This Article argues against that approach. Privacy and property are fundamentally different concepts. At heart, the term "property" connotes control within the marketplace and over something that is disaggregated or alienable from the self. "Privacy," in contrast, connotes control over access to the self as well as things close to, intimately connected to, and about the self. Given these different meanings, a regime of property rights in genetic information would impoverish our understanding of that information, ourselves, and the relationships we hope will be built around and through its disclosure. This Article explores our interests in genetic information in order to deepen our understanding of the ongoing discourse about the distinction between property and privacy. It develops a conception of genetic privacy with a strong relational component. We ordinarily share genetic information in the context of relationships in which disclosure is important to the relationship--family, intimate, doctor-patient, researcher-participant, employer-employee, and insurer-insured relationships. Such disclosure makes us vulnerable to and dependent on the person to whom we disclose it. As a result, trust is essential to the integrity of these relationships and our sharing of genetic information. Genetic privacy can protect our vulnerability in these relationships and enhance the trust we hope to have in them. Property, in contrast, by

[Genetics and epigenetics in autism].

Science.gov (United States)

Nakayama, Atsuo; Masaki, Shiego; Aoki, Eiko

2006-11-01

Autism is a behaviorally defined syndrome characterized by impaired social interaction and communication, and restricted, stereotyped interests and behaviors. Several lines of evidence support the contention that genetic factors are a large component to autism etiology. However, in spite of vigorous genetic studies, no single causative or susceptibility gene common in autism has been identified. Thus multiple susceptibility genes in interaction are considered to account for the disorder. Furthermore, environmental risk factors can accelerate the autism development of. Recent advances in understanding the epigenetic regulation may shed light on the interaction among multiple genetic factors and environmental factors.

Hyperspherical Treatment of Strongly-Interacting Few-Fermion Systems in One Dimension

DEFF Research Database (Denmark)

Volosniev, A. G.; Fedorov, D. V.; Jensen, A. S.

2015-01-01

We examine a one-dimensional two-component fermionic system in a trap, assuming that all particles have the same mass and interact through a strong repulsive zero-range force. First we show how a simple system of three strongly interacting particles in a harmonic trap can be treated using...

Working Memory and Parent-Rated Components of Attention in Middle Childhood: A Behavioral Genetic Study

Science.gov (United States)

Deater-Deckard, Kirby; Cutting, Laurie; Thompson, Lee A.; Petrill, Stephen A.

2012-01-01

The purpose of the current study was to investigate potential genetic and environmental correlations between working memory and three behavioral aspects of the attention network (i.e., executive, alerting, and orienting) using a twin design. Data were from 90 monozygotic (39% male) and 112 same-sex dizygotic (41% male) twins. Individual differences in working memory performance (digit span) and parent-rated measures of executive, alerting, and orienting attention included modest to moderate genetic variance, modest shared environmental variance, and modest to moderate nonshared environmental variance. As hypothesized, working memory performance was correlated with executive and alerting attention, but not orienting attention. The correlation between working memory, executive attention, and alerting attention was completely accounted for by overlapping genetic covariance, suggesting a common genetic mechanism or mechanisms underlying the links between working memory and certain parent-rated indicators of attentive behavior. PMID:21948215

Genetic diversity of grape germplasm as revealed by microsatellite ...

African Journals Online (AJOL)

aghomotsegin

In this work, cluster analysis and principal component analysis (PCA) were used to study the genetic ... Key words: Vitis vinifera L., simple sequence repeat (SSR), genetic diversity, .... The data were used for the following statistical analyses.

Journal of Genetics | Indian Academy of Sciences

Indian Academy of Sciences (India)

Home; Journals; Journal of Genetics. Jinping Wang. Articles written in Journal of Genetics. Volume 91 Issue 3 December 2012 pp 303-312 Research Article. Conditional QTL mapping of protein content in wheat with respect to grain yield and its components · Lin Wang Fa Cui Jinping Wang Li Jun Anming Ding Chunhua ...

Glioblastomas with Oligodendroglial Component ? Common Origin of the Different Histological Parts and Genetic Subclassification

OpenAIRE

Klink, Barbara; Schlingelhof, Ben; Klink, Martin; Stout-Weider, Karen; Patt, Stephan; Schrock, Evelin

2010-01-01

Background: Glioblastomas are the most common and most malignant brain tumors in adults. A small subgroup of glioblastomas contains areas with histological features of oligodendroglial differentiation (GBMO). Our objective was to genetically characterize the oligodendroglial and the astrocytic parts of GBMOs and correlate morphologic and genetic features with clinical data. Methods: The oligodendroglial and the ?classic? glioblastoma parts of 13 GBMO were analyzed separately by interphase flu...

Genetic diversity and landscape genetic structure of otter (Lutra lutra) populations in Europe

DEFF Research Database (Denmark)

Mucci, Nadia; Arrendal, Johanna; Ansorge, Hermann

2010-01-01

Eurasian otter populations strongly declined and partially disappeared due to global and local causes (habitat destruction, water pollution, human persecution) in parts of their continental range. Conservation strategies, based on reintroduction projects or restoration of dispersal corridors...... and landscape genetic analyses however indicate that local populations are genetically differentiated, perhaps as consequence of post-glacial demographic fluctuations and recent isolation. These results delineate a framework that should be used for implementing conservation programs in Europe, particularly...

Fractional energy states of strongly-interacting bosons in one dimension

DEFF Research Database (Denmark)

Zinner, Nikolaj Thomas; G. Volosniev, A.; V. Fedorov, D.

2014-01-01

We study two-component bosonic systems with strong inter-species and vanishing intra-species interactions. A new class of exact eigenstates is found with energies that are {\\it not} sums of the single-particle energies with wave functions that have the characteristic feature that they vanish over...... than three particles. The states can be probed using the same techniques that have recently been used for fermionic few-body systems in quasi-1D.......We study two-component bosonic systems with strong inter-species and vanishing intra-species interactions. A new class of exact eigenstates is found with energies that are {\\it not} sums of the single-particle energies with wave functions that have the characteristic feature that they vanish over...... extended regions of coordinate space. This is demonstrated in an analytically solvable model for three equal mass particles, two of which are identical bosons, which is exact in the strongly-interacting limit. We numerically verify our results by presenting the first application of the stochastic...

Three-dimensional electromagnetic strong turbulence. I. Scalings, spectra, and field statistics

International Nuclear Information System (INIS)

Graham, D. B.; Robinson, P. A.; Cairns, Iver H.; Skjaeraasen, O.

2011-01-01

The first fully three-dimensional (3D) simulations of large-scale electromagnetic strong turbulence (EMST) are performed by numerically solving the electromagnetic Zakharov equations for electron thermal speeds ν e with ν e /c≥0.025. The results of these simulations are presented, focusing on scaling behavior, energy density spectra, and field statistics of the Langmuir (longitudinal) and transverse components of the electric fields during steady-state strong turbulence, where multiple wave packets collapse simultaneously and the system is approximately statistically steady in time. It is shown that for ν e /c > or approx. 0.17 strong turbulence is approximately electrostatic and can be explained using the electrostatic two-component model. For v e /c > or approx. 0.17 the power-law behaviors of the scalings, spectra, and field statistics differ from the electrostatic predictions and results because ν e /c is sufficiently high to allow transverse modes to become trapped in density wells. The results are compared with those of past 3D electrostatic strong turbulence (ESST) simulations and 2D EMST simulations. For number density perturbations, the scaling behavior, spectra, and field statistics are shown to be only weakly dependent on ν e /c, whereas the Langmuir and transverse scalings, spectra, and field statistics are shown to be strongly dependent on ν e /c. Three-dimensional EMST is shown to have features in common with 2D EMST, such as a two-component structure and trapping of transverse modes which are dependent on ν e /c.

Genetic influences in caries and periodontal diseases.

Science.gov (United States)

Hassell, T M; Harris, E L

1995-01-01

Deciphering the relative roles of heredity and environmental factors ("nature vs. nurture") in the pathogenesis of dental caries and diseases of the periodontium has occupied clinical and basic researchers for decades. Success in the endeavor has come more easily in the case of caries; the complex interactions that occur between host-response mechanisms and putative microbiologic pathogens in periodontal disease have made elucidation of genetic factors in disease susceptibility more difficult. In addition, during the 30-year period between 1958 and 1987, only meager resources were targeted toward the "nature" side of the nature/nurture dipole in periodontology. In this article, we present a brief history of the development of genetic epistemology, then describe the three main research mechanisms by which questions about the hereditary component of diseases in humans can be addressed. A critical discussion of the evidence for a hereditary component in caries susceptibility is next presented, also from a historical perspective. The evolution of knowledge concerning possible genetic ("endogenous", "idiotypic") factors in the pathogenesis of inflammatory periodontal disease is initiated with an analysis of some foreign-language (primarily German) literature that is likely to be unfamiliar to the reader. We identify a turning point at about 1960, when the periodontal research community turned away from genetics in favor of microbiology research. During the past five years, investigators have re-initiated the search for the hereditary component in susceptibility to common adult periodontal disease; this small but growing body of literature is reviewed. Recent applications of in vitro methods for genetic analyses in periodontal research are presented, with an eye toward a future in which persons who are at risk--genetically predisposed--to periodontal disease may be identified and targeted for interventive strategies. Critical is the realization that genes and environment

Replaceable LMFBR core components

International Nuclear Information System (INIS)

Evans, E.A.; Cunningham, G.W.

1976-01-01

Much progress has been made in understanding material and component performance in the high temperature, fast neutron environment of the LMFBR. Current data have provided strong assurance that the initial core component lifetime objectives of FFTF and CRBR can be met. At the same time, this knowledge translates directly into the need for improved core designs that utilize improved materials and advanced fuels required to meet objectives of low doubling times and extended core component lifetimes. An industrial base for the manufacture of quality core components has been developed in the US, and all procurements for the first two core equivalents for FFTF will be completed this year. However, the problem of fabricating recycled plutonium while dramatically reducing fabrication costs, minimizing personnel exposure, and protecting public health and safety must be addressed

Dynamics and genetic structure of Argentine ant supercolonies in their native range

DEFF Research Database (Denmark)

Vogel, Valérie; Pedersen, Jes S; d'Ettorre, Patrizia

2009-01-01

analyses revealed the presence of 11 supercolonies (width 1 to 515 m) over a 3-km transect. As in the introduced range, there was always strong aggression between but never within supercolonies. The genetic data were in perfect agreement with the behavioral tests, all nests being assigned to identical...... supercolonies with the different methods. There was strong genetic differentiation between supercolonies but no genetic differentiation among nests within supercolonies. We never found more than a single mitochondrial haplotype per supercolony, further supporting the view that supercolonies are closed breeding...

Exploring the genetics and non-cell autonomous mechanisms underlying ALS/FTLD.

Science.gov (United States)

Chen, Hongbo; Kankel, Mark W; Su, Susan C; Han, Steve W S; Ofengeim, Dimitry

2018-03-01

Although amyotrophic lateral sclerosis (ALS), also known as Lou Gehrig's disease, was first described in 1874, a flurry of genetic discoveries in the last 10 years has markedly increased our understanding of this disease. These findings have not only enhanced our knowledge of mechanisms leading to ALS, but also have revealed that ALS shares many genetic causes with another neurodegenerative disease, frontotemporal lobar dementia (FTLD). In this review, we survey how recent genetic studies have bridged our mechanistic understanding of these two related diseases and how the genetics behind ALS and FTLD point to complex disorders, implicating non-neuronal cell types in disease pathophysiology. The involvement of non-neuronal cell types is consistent with a non-cell autonomous component in these diseases. This is further supported by studies that identified a critical role of immune-associated genes within ALS/FTLD and other neurodegenerative disorders. The molecular functions of these genes support an emerging concept that various non-autonomous functions are involved in neurodegeneration. Further insights into such a mechanism(s) will ultimately lead to a better understanding of potential routes of therapeutic intervention. Facts ALS and FTLD are severe neurodegenerative disorders on the same disease spectrum. Multiple cellular processes including dysregulation of RNA homeostasis, imbalance of proteostasis, contribute to ALS/FTLD pathogenesis. Aberrant function in non-neuronal cell types, including microglia, contributes to ALS/FTLD. Strong neuroimmune and neuroinflammatory components are associated with ALS/FTLD patients. Open Questions Why can patients with similar mutations have different disease manifestations, i.e., why do C9ORF72 mutations lead to motor neuron loss in some patients while others exhibit loss of neurons in the frontotemporal lobe? Do ALS causal mutations result in microglial dysfunction and contribute to ALS/FTLD pathology? How do microglia

Genetic and environmental influences on female sexual orientation, childhood gender typicality and adult gender identity.

Directory of Open Access Journals (Sweden)

Andrea Burri

Full Text Available BACKGROUND: Human sexual orientation is influenced by genetic and non-shared environmental factors as are two important psychological correlates--childhood gender typicality (CGT and adult gender identity (AGI. However, researchers have been unable to resolve the genetic and non-genetic components that contribute to the covariation between these traits, particularly in women. METHODOLOGY/PRINCIPAL FINDINGS: Here we performed a multivariate genetic analysis in a large sample of British female twins (N = 4,426 who completed a questionnaire assessing sexual attraction, CGT and AGI. Univariate genetic models indicated modest genetic influences on sexual attraction (25%, AGI (11% and CGT (31%. For the multivariate analyses, a common pathway model best fitted the data. CONCLUSIONS/SIGNIFICANCE: This indicated that a single latent variable influenced by a genetic component and common non-shared environmental component explained the association between the three traits but there was substantial measurement error. These findings highlight common developmental factors affecting differences in sexual orientation.

A heritable component in sex ratio and caste determination in a Cardiocondyla ant

Directory of Open Access Journals (Sweden)

Heinze Jürgen

2009-10-01

Full Text Available Abstract Studies on sex ratios in social insects provide among the most compelling evidence for the importance of kin selection in social evolution. The elegant synthesis of Fisher's sex ratio principle and Hamilton's inclusive fitness theory predicts that colony-level sex ratios vary with the colonies' social and genetic structures. Numerous empirical studies in ants, bees, and wasps have corroborated these predictions. However, the evolutionary optimization of sex ratios requires genetic variation, but one fundamental determinant of sex ratios - the propensity of female larvae to develop into young queens or workers ("queen bias" - is thought to be largely controlled by the environment. Evidence for a genetic influence on sex ratio and queen bias is as yet restricted to a few taxa, in particular hybrids. Because of the very short lifetime of their queens, ants of the genus Cardiocondyla are ideal model systems for the study of complete lifetime reproductive success, queen bias, and sex ratios. We found that lifetime sex ratios of the ant Cardiocondyla kagutsuchi have a heritable component. In experimental single-queen colonies, 22 queens from a genetic lineage with a highly female-biased sex ratio produced significantly more female-biased offspring sex ratios than 16 queens from a lineage with a more male-biased sex ratio (median 91.5% vs. 58.5% female sexuals. Sex ratio variation resulted from different likelihood of female larvae developing into sexuals (median 50% vs. 22.6% female sexuals even when uniformly nursed by workers from another colony. Consistent differences in lifetime sex ratios and queen bias among queens of C. kagutsuchi suggest that heritable, genetic or maternal effects strongly affect caste determination. Such variation might provide the basis for adaptive evolution of queen and worker strategies, though it momentarily constrains the power of workers and queens to optimize caste ratios.

A heritable component in sex ratio and caste determination in a Cardiocondyla ant.

Science.gov (United States)

Frohschammer, Sabine; Heinze, Jürgen

2009-10-28

Studies on sex ratios in social insects provide among the most compelling evidence for the importance of kin selection in social evolution. The elegant synthesis of Fisher's sex ratio principle and Hamilton's inclusive fitness theory predicts that colony-level sex ratios vary with the colonies' social and genetic structures. Numerous empirical studies in ants, bees, and wasps have corroborated these predictions. However, the evolutionary optimization of sex ratios requires genetic variation, but one fundamental determinant of sex ratios - the propensity of female larvae to develop into young queens or workers ("queen bias") - is thought to be largely controlled by the environment. Evidence for a genetic influence on sex ratio and queen bias is as yet restricted to a few taxa, in particular hybrids.Because of the very short lifetime of their queens, ants of the genus Cardiocondyla are ideal model systems for the study of complete lifetime reproductive success, queen bias, and sex ratios. We found that lifetime sex ratios of the ant Cardiocondyla kagutsuchi have a heritable component. In experimental single-queen colonies, 22 queens from a genetic lineage with a highly female-biased sex ratio produced significantly more female-biased offspring sex ratios than 16 queens from a lineage with a more male-biased sex ratio (median 91.5% vs. 58.5% female sexuals). Sex ratio variation resulted from different likelihood of female larvae developing into sexuals (median 50% vs. 22.6% female sexuals) even when uniformly nursed by workers from another colony.Consistent differences in lifetime sex ratios and queen bias among queens of C. kagutsuchi suggest that heritable, genetic or maternal effects strongly affect caste determination. Such variation might provide the basis for adaptive evolution of queen and worker strategies, though it momentarily constrains the power of workers and queens to optimize caste ratios.

Effects of interaction imbalance in a strongly repulsive one-dimensional Bose gas

DEFF Research Database (Denmark)

Barfknecht, Rafael Emilio; Zinner, Nikolaj Thomas; Foerster, Angela

2018-01-01

We calculate the spatial distributions and the dynamics of a few-body two-component strongly interacting Bose gas confined to an effectively one-dimensional trapping potential. We describe the densities for each component in the trap for different interaction and population imbalances. We calculate...

Population Genetics of the São Tomé Caecilian (Gymnophiona: Dermophiidae: Schistometopum thomense) Reveals Strong Geographic Structuring

Science.gov (United States)

Stoelting, Ricka E.; Measey, G. John; Drewes, Robert C.

2014-01-01

Islands provide exciting opportunities for exploring ecological and evolutionary mechanisms. The oceanic island of São Tomé in the Gulf of Guinea exhibits high diversity of fauna including the endemic caecilian amphibian, Schistometopum thomense. Variation in pigmentation, morphology and size of this taxon over its c. 45 km island range is extreme, motivating a number of taxonomic, ecological, and evolutionary hypotheses to explain the observed diversity. We conducted a population genetic study of S. thomense using partial sequences of two mitochondrial DNA genes (ND4 and 16S), together with morphological examination, to address competing hypotheses of taxonomic or clinal variation. Using Bayesian phylogenetic analysis and Spatial Analysis of Molecular Variance, we found evidence of four geographic clades, whose range and approximated age (c. 253 Kya – 27 Kya) are consistent with the spread and age of recent volcanic flows. These clades explained 90% of variation in ND4 (φCT = 0.892), and diverged by 4.3% minimum pairwise distance at the deepest node. Most notably, using Mismatch Distributions and Mantel Tests, we identified a zone of population admixture that dissected the island. In the northern clade, we found evidence of recent population expansion (Fu's Fs = −13.08 and Tajima's D = −1.80) and limited dispersal (Mantel correlation coefficient = 0.36, p = 0.01). Color assignment to clades was not absolute. Paired with multinomial regression of chromatic data, our analyses suggested that the genetic groups and a latitudinal gradient together describe variation in color of S. thomense. We propose that volcanism and limited dispersal ability are the likely proximal causes of the observed genetic structure. This is the first population genetic study of any caecilian and demonstrates that these animals have deep genetic divisions over very small areas in accordance with previous speculations of low dispersal abilities. PMID:25171066

Strongly enhanced colorectal cancer risk stratification by combining family history and genetic risk score

Directory of Open Access Journals (Sweden)

Weigl K

2018-01-01

Full Text Available Korbinian Weigl,1,2 Jenny Chang-Claude,3,4 Phillip Knebel,5 Li Hsu,6 Michael Hoffmeister,1 Hermann Brenner1,2,7 1Division of Clinical Epidemiology and Aging Research, German Cancer Research Center (DKFZ, Heidelberg, 2German Cancer Consortium (DKTK, German Cancer Research Center (DKFZ, Heidelberg, 3Unit of Genetic Epidemiology, German Cancer Research Center (DKFZ, Heidelberg, 4University Cancer Center Hamburg, University Medical Center Hamburg-Eppendorf, Hamburg, 5Department for General, Visceral and Transplantation Surgery, University Heidelberg, Heidelberg, Germany; 6Public Health Sciences Division, Fred Hutchinson Cancer Research Center, Seattle, WA, USA; 7Division of Preventive Oncology, German Cancer Research Center (DKFZ and National Center for Tumor Diseases (NCT, Heidelberg, Germany Background and aim: Family history (FH and genetic risk scores (GRSs are increasingly used for risk stratification for colorectal cancer (CRC screening. However, they were mostly considered alternatively rather than jointly. The aim of this study was to assess the potential of individual and joint risk stratification for CRC by FH and GRS.Patients and methods: A GRS was built based on the number of risk alleles in 53 previously identified single-nucleotide polymorphisms among 2,363 patients with a first diagnosis of CRC and 2,198 controls in DACHS [colorectal cancer: chances for prevention through screening], a population-based case-control study in Germany. Associations between GRS and FH with CRC risk were quantified by multiple logistic regression.Results: A total of 316 cases (13.4% and 214 controls (9.7% had a first-degree relative (FDR with CRC (adjusted odds ratio [aOR] 1.86, 95% CI 1.52–2.29. A GRS in the highest decile was associated with a 3.0-fold increased risk of CRC (aOR 3.00, 95% CI 2.24–4.02 compared with the lowest decile. This association was tentatively more pronounced in older age groups. FH and GRS were essentially unrelated, and their

Genetic and neurobiological aspects of attention deficit hyperactive disorder: a review.

OpenAIRE

Hechtman, L

1994-01-01

This paper reviews key studies that have addressed genetic and neurobiological aspects in attention deficit hyperactive disorder. Genetic studies can be divided into three distinct types: twin, adoption, and family studies. Evidence for a particular mode of inheritance and the possible specific genetic abnormalities are also explored. There is strong evidence of genetic involvement in this condition, although a clear-cut mode of inheritance and specific genetic abnormalities are yet to be det...

Diffraction analysis of materials under strong plastic deformation

International Nuclear Information System (INIS)

Pyzalla, A.

2001-01-01

The applicability of X-ray diffraction in analyses of the microstructure texture and intrinsic stresses of materials under strong plastic deformation is illustrated by examples and discussed. The experimental methods and findings are supplemented by numeric calculations. It is shown how the microstructure, texture and intrinsic stresses can thus be optimized already in the production process. Analyses of changes in materials during operation of a component provide information on loads and material response to loads which can then be used for optimization of the component, e.g. by constructional modifications or selective heat treatment [de

Direct and maternal genetic effects for birth weight in dorper and ...

African Journals Online (AJOL)

Variance components for birth (BWT) in Dorper and Mutton Merino sheep were estimated by Average Information Restricted Maximum Likelihood (AIREML). Animal model was fitted allowing for genetic maternal effects and a genetic covariance between direct and maternal effects. Estimates of heritability for direct genetic ...

A strongly interacting polaritonic quantum dot

Science.gov (United States)

Jia, Ningyuan; Schine, Nathan; Georgakopoulos, Alexandros; Ryou, Albert; Clark, Logan W.; Sommer, Ariel; Simon, Jonathan

2018-06-01

Polaritons are promising constituents of both synthetic quantum matter1 and quantum information processors2, whose properties emerge from their components: from light, polaritons draw fast dynamics and ease of transport; from matter, they inherit the ability to collide with one another. Cavity polaritons are particularly promising as they may be confined and subjected to synthetic magnetic fields controlled by cavity geometry3, and furthermore they benefit from increased robustness due to the cavity enhancement in light-matter coupling. Nonetheless, until now, cavity polaritons have operated only in a weakly interacting mean-field regime4,5. Here we demonstrate strong interactions between individual cavity polaritons enabled by employing highly excited Rydberg atoms as the matter component of the polaritons. We assemble a quantum dot composed of approximately 150 strongly interacting Rydberg-dressed 87Rb atoms in a cavity, and observe blockaded transport of photons through it. We further observe coherent photon tunnelling oscillations, demonstrating that the dot is zero-dimensional. This work establishes the cavity Rydberg polariton as a candidate qubit in a photonic information processor and, by employing multiple resonator modes as the spatial degrees of freedom of a photonic particle, the primary ingredient to form photonic quantum matter6.

How Darwinian reductionism refutes genetic determinism.

Science.gov (United States)

Rosoff, Philip M; Rosenberg, Alex

2006-03-01

Genetic determinism labels the morally problematical claim that some socially significant traits, traits we care about, such as sexual orientation, gender roles, violence, alcoholism, mental illness, intelligence, are largely the results of the operation of genes and not much alterable by environment, learning or other human intervention. Genetic determinism does not require that genes literally fix these socially significant traits, but rather that they constrain them within narrow channels beyond human intervention. In this essay we analyze genetic determinism in light of what is now known about the inborn error of metabolism phenylketonuria (PKU), which has for so long been the poster child 'simple' argument in favor of some form of genetic determinism. We demonstrate that this case proves the exact opposite of what it has been proposed to support and provides a strong refutation of genetic determinism in all its guises.

Loss of genetic diversity in Maculinea populations over 10 years

DEFF Research Database (Denmark)

Nash, David Richard; Lomborg, Andreas Eg

I will present the results of research on the population genetics of Maculinea alcon and M. arion in Southern scandinavia, which shows a strong decrease in genetic diversity in most populations, even if those populations are apparently otherwise healthy....

Genetic analysis of fertility restoration under CGMS system in rice ...

Indian Academy of Sciences (India)

restore complete fertility of a certain CMS line by various restorer lines (Tan et ... Keywords. rice; heterosis; three-way test cross; fertility restoration genetics. Journal of ..... plants indicating a strong genetic load of maintenance in. DE2. Table 8.

Exploiting Genetic Variation of Fiber Components and Morphology in Juvenile Loblolly Pine

Energy Technology Data Exchange (ETDEWEB)

Chang, Hou-Min; Kadia, John F.; Li, Bailian; Sederoff, Ron

2005-06-30

In order to ensure the global competitiveness of the Pulp and Paper Industry in the Southeastern U.S., more wood with targeted characteristics have to be produced more efficiently on less land. The objective of the research project is to provide a molecular genetic basis for tree breeding of desirable traits in juvenile loblolly pine, using a multidisciplinary research approach. We developed micro analytical methods for determine the cellulose and lignin content, average fiber length, and coarseness of a single ring in a 12 mm increment core. These methods allow rapid determination of these traits in micro scale. Genetic variation and genotype by environment interaction (GxE) were studied in several juvenile wood traits of loblolly pine (Pinus taeda L.). Over 1000 wood samples of 12 mm increment cores were collected from 14 full-sib families generated by a 6-parent half-diallel mating design (11-year-old) in four progeny tests. Juvenile (ring 3) and transition (ring 8) for each increment core were analyzed for cellulose and lignin content, average fiber length, and coarseness. Transition wood had higher cellulose content, longer fiber and higher coarseness, but lower lignin than juvenile wood. General combining ability variance for the traits in juvenile wood explained 3 to 10% of the total variance, whereas the specific combining ability variance was negligible or zero. There were noticeable full-sib family rank changes between sites for all the traits. This was reflected in very high specific combining ability by site interaction variances, which explained from 5% (fiber length) to 37% (lignin) of the total variance. Weak individual-tree heritabilities were found for cellulose, lignin content and fiber length at the juvenile and transition wood, except for lignin at the transition wood (0.23). Coarseness had moderately high individual-tree heritabilities at both the juvenile (0.39) and transition wood (0.30). Favorable genetic correlations of volume and stem

Genetic background of claw health in dairy cattle

NARCIS (Netherlands)

Spek, van der D.

2015-01-01

<strong>Abstract>

Van der Spek, D. (2015). Genetic background of claw health in dairy cattle. PhD thesis, Wageningen University, the Netherlands.

Claw disorders affect cow welfare and profitability of farms and as such are important traits relevant to dairy cattle breeding.

Genetic Diversity and Population Structure of the Critically Endangered Yangtze Finless Porpoise (Neophocaena asiaeorientalis asiaeorientalis as Revealed by Mitochondrial and Microsatellite DNA

Directory of Open Access Journals (Sweden)

Minmin Chen

2014-06-01

Full Text Available Ecological surveys have indicated that the population of the critically endangered Yangtze finless porpoise (YFP, Neophocaena asiaeorientalis asiaeorientalis is becoming increasingly small and fragmented, and will be at high risk of extinction in the near future. Genetic conservation of this population will be an important component of the long-term conservation effort. We used a 597 base pair mitochondrial DNA (mtDNA control region and 11 microsatellite loci to analyze the genetic diversity and population structure of the YFP. The analysis of both mtDNA and microsatellite loci suggested that the genetic diversity of the YFP will possibly decrease in the future if the population keeps declining at a rapid rate, even though these two types of markers revealed different levels of genetic diversity. In addition, mtDNA revealed strong genetic differentiation between one local population, Xingchang–Shishou (XCSS, and the other five downstream local populations; furthermore, microsatellite DNA unveiled fine but significant genetic differentiation between three of the local populations (not only XCSS but also Poyang Lake (PY and Tongling (TL and the other local populations. With an increasing number of distribution gaps appearing in the Yangtze main steam, the genetic differentiation of local populations will likely intensify in the future. The YFP is becoming a genetically fragmented population. Therefore, we recommend attention should be paid to the genetic conservation of the YFP.

Genetic Diversity and Population Structure of the Critically Endangered Yangtze Finless Porpoise (Neophocaena asiaeorientalis asiaeorientalis) as Revealed by Mitochondrial and Microsatellite DNA

Science.gov (United States)

Chen, Minmin; Zheng, Jinsong; Wu, Min; Ruan, Rui; Zhao, Qingzhong; Wang, Ding

2014-01-01

Ecological surveys have indicated that the population of the critically endangered Yangtze finless porpoise (YFP, Neophocaena asiaeorientalis asiaeorientalis) is becoming increasingly small and fragmented, and will be at high risk of extinction in the near future. Genetic conservation of this population will be an important component of the long-term conservation effort. We used a 597 base pair mitochondrial DNA (mtDNA) control region and 11 microsatellite loci to analyze the genetic diversity and population structure of the YFP. The analysis of both mtDNA and microsatellite loci suggested that the genetic diversity of the YFP will possibly decrease in the future if the population keeps declining at a rapid rate, even though these two types of markers revealed different levels of genetic diversity. In addition, mtDNA revealed strong genetic differentiation between one local population, Xingchang–Shishou (XCSS), and the other five downstream local populations; furthermore, microsatellite DNA unveiled fine but significant genetic differentiation between three of the local populations (not only XCSS but also Poyang Lake (PY) and Tongling (TL)) and the other local populations. With an increasing number of distribution gaps appearing in the Yangtze main steam, the genetic differentiation of local populations will likely intensify in the future. The YFP is becoming a genetically fragmented population. Therefore, we recommend attention should be paid to the genetic conservation of the YFP. PMID:24968271

Glioblastomas with Oligodendroglial Component – Common Origin of the Different Histological Parts and Genetic Subclassification

Directory of Open Access Journals (Sweden)

Barbara Klink

2010-01-01

Full Text Available Background: Glioblastomas are the most common and most malignant brain tumors in adults. A small subgroup of glioblastomas contains areas with histological features of oligodendroglial differentiation (GBMO. Our objective was to genetically characterize the oligodendroglial and the astrocytic parts of GBMOs and correlate morphologic and genetic features with clinical data.

Strong population genetic structure and larval dispersal capability of the burrowing ghost shrimp (Neotrypaea californiensis)

Science.gov (United States)

The burrowing ghost shrimp, Neotrypaea californiensis, is a vital member of the estuarine benthic community. Dense populations of shrimp are found in the major estuaries of Washington and Oregon. Our study determines the genetic structure of shrimp populations in order to gain ...

Methods for Analyzing Multivariate Phenotypes in Genetic Association Studies

Directory of Open Access Journals (Sweden)

Qiong Yang

2012-01-01

Full Text Available Multivariate phenotypes are frequently encountered in genetic association studies. The purpose of analyzing multivariate phenotypes usually includes discovery of novel genetic variants of pleiotropy effects, that is, affecting multiple phenotypes, and the ultimate goal of uncovering the underlying genetic mechanism. In recent years, there have been new method development and application of existing statistical methods to such phenotypes. In this paper, we provide a review of the available methods for analyzing association between a single marker and a multivariate phenotype consisting of the same type of components (e.g., all continuous or all categorical or different types of components (e.g., some are continuous and others are categorical. We also reviewed causal inference methods designed to test whether the detected association with the multivariate phenotype is truly pleiotropy or the genetic marker exerts its effects on some phenotypes through affecting the others.

A novel approach to analyzing fMRI and SNP data via parallel independent component analysis

Science.gov (United States)

Liu, Jingyu; Pearlson, Godfrey; Calhoun, Vince; Windemuth, Andreas

2007-03-01

There is current interest in understanding genetic influences on brain function in both the healthy and the disordered brain. Parallel independent component analysis, a new method for analyzing multimodal data, is proposed in this paper and applied to functional magnetic resonance imaging (fMRI) and a single nucleotide polymorphism (SNP) array. The method aims to identify the independent components of each modality and the relationship between the two modalities. We analyzed 92 participants, including 29 schizophrenia (SZ) patients, 13 unaffected SZ relatives, and 50 healthy controls. We found a correlation of 0.79 between one fMRI component and one SNP component. The fMRI component consists of activations in cingulate gyrus, multiple frontal gyri, and superior temporal gyrus. The related SNP component is contributed to significantly by 9 SNPs located in sets of genes, including those coding for apolipoprotein A-I, and C-III, malate dehydrogenase 1 and the gamma-aminobutyric acid alpha-2 receptor. A significant difference in the presences of this SNP component is found between the SZ group (SZ patients and their relatives) and the control group. In summary, we constructed a framework to identify the interactions between brain functional and genetic information; our findings provide new insight into understanding genetic influences on brain function in a common mental disorder.

Population genetic structure of the people of Qatar.

Science.gov (United States)

Hunter-Zinck, Haley; Musharoff, Shaila; Salit, Jacqueline; Al-Ali, Khalid A; Chouchane, Lotfi; Gohar, Abeer; Matthews, Rebecca; Butler, Marcus W; Fuller, Jennifer; Hackett, Neil R; Crystal, Ronald G; Clark, Andrew G

2010-07-09

People of the Qatar peninsula represent a relatively recent founding by a small number of families from three tribes of the Arabian Peninsula, Persia, and Oman, with indications of African admixture. To assess the roles of both this founding effect and the customary first-cousin marriages among the ancestral Islamic populations in Qatar's population genetic structure, we obtained and genotyped with Affymetrix 500k SNP arrays DNA samples from 168 self-reported Qatari nationals sampled from Doha, Qatar. Principal components analysis was performed along with samples from the Human Genetic Diversity Project data set, revealing three clear clusters of genotypes whose proximity to other human population samples is consistent with Arabian origin, a more eastern or Persian origin, and individuals with African admixture. The extent of linkage disequilibrium (LD) is greater than that of African populations, and runs of homozygosity in some individuals reflect substantial consanguinity. However, the variance in runs of homozygosity is exceptionally high, and the degree of identity-by-descent sharing generally appears to be lower than expected for a population in which nearly half of marriages are between first cousins. Despite the fact that the SNPs of the Affymetrix 500k chip were ascertained with a bias toward SNPs common in Europeans, the data strongly support the notion that the Qatari population could provide a valuable resource for the mapping of genes associated with complex disorders and that tests of pairwise interactions are particularly empowered by populations with elevated LD like the Qatari. Copyright 2010 The American Society of Human Genetics. Published by Elsevier Inc. All rights reserved.

Transcriptional stimulation of rate-limiting components of the autophagic pathway improves plant fitness

Czech Academy of Sciences Publication Activity Database

Minina, E. A.; Moschou, P. N.; Vetukuri, R. R.; Sanchez-Vera, V.; Cardoso, C.; Liu, Q.; Elander, P. H.; Dalman, K.; Beganovic, M.; Lindberg Yilmaz, J.; Marmon, S.; Shabala, S.; Suarez, M.; Ljung, K.; Novák, Ondřej; Shabala, S.; Stymne, S.; Hofius, D.; Bozhkov, P. V.

2018-01-01

Roč. 69, č. 6 (2018), s. 1415-1432 ISSN 0022-0957 Institutional support: RVO:61389030 Keywords : Aging * ATG genes * Autophagy * Autophagy-related ubiquitin-like conjugation systems * Biomass * Oil content * Ratelimiting components of autophagic flux * Seed yield * Stress resistance * Transcriptional regulation Subject RIV: EB - Genetics ; Molecular Biology OBOR OECD: Genetics and heredity (medical genetics to be 3) Impact factor: 5.830, year: 2016

Nontraditional inheritance: Genetics and the nature of science, now titled, The puzzle of inheritance: Genetics and the methods of science. Final report

Energy Technology Data Exchange (ETDEWEB)

McInerney, J.D.

1998-08-31

This project led to the development of an instructional module designed for use in high school biology classes. The module contains two major components. The first is an overview for teachers, which introduces the module, describes the Human Genome Project, and addresses issues in the philosophy of science and some of the ethical, legal, and social implications of research in genetics. It provides a survey of fundamental genetics concepts and of new, nontraditional concepts of inheritance. The second component provides six instructional activities appropriate for high school or introductory college students.

Genetic basis of variation for salinity tolerance in okra (abelmoschus esculentus L.)

International Nuclear Information System (INIS)

Ikram-ul-Haq; Khan, A.A.; Azhar, F.M.; Ullah, E.

2010-01-01

The development of salt tolerant plants through selection and breeding depends on the presence of the genetic variability within the crop species in response to salt stress, which must have significant genetic component. Such information is not extensively available in vegetable crops. The present study was carried out to gain some information on the genetic basis of variation for salinity tolerance in okra. North Carolina Mating Design II (NCM II) was used for the estimation of genetic components of variation in the traits affecting salinity tolerance. The inheritance of the traits affecting salinity tolerance at the seedling stage appeared to be controlled by both additive and non-additive effects (dominance and epistasis). The narrow sense heritability estimates ranged from 40 to 65% and 7 to 70% and the estimates of broad sense heritability ranged from 65 to 99% and 20 to 99% for absolute and relative values. The additive effects were relatively more prominent and narrow sense heritability was moderate. The high additive component for absolute Na/sup +/ and K/sup +//Na/sup +/ ratio at 60 and 80 mM NaCl, relative Na+ at 80 mM NaCl suggested that improvement for salinity tolerance in okra would be possible on the basis of these characteristics through selection and breeding. The genetic variation for tolerance to NaCl salinity existed among the okra genotypes, which had considerable heritable component and, therefore, genetic improvement of okra genotypes for salinity tolerance through recurrent selection method is possible. (author)

Strong spin-photon coupling in silicon

Science.gov (United States)

Samkharadze, N.; Zheng, G.; Kalhor, N.; Brousse, D.; Sammak, A.; Mendes, U. C.; Blais, A.; Scappucci, G.; Vandersypen, L. M. K.

2018-03-01

Long coherence times of single spins in silicon quantum dots make these systems highly attractive for quantum computation, but how to scale up spin qubit systems remains an open question. As a first step to address this issue, we demonstrate the strong coupling of a single electron spin and a single microwave photon. The electron spin is trapped in a silicon double quantum dot, and the microwave photon is stored in an on-chip high-impedance superconducting resonator. The electric field component of the cavity photon couples directly to the charge dipole of the electron in the double dot, and indirectly to the electron spin, through a strong local magnetic field gradient from a nearby micromagnet. Our results provide a route to realizing large networks of quantum dot–based spin qubit registers.

Primer Part 1-The building blocks of epilepsy genetics.

Science.gov (United States)

Helbig, Ingo; Heinzen, Erin L; Mefford, Heather C

2016-06-01

This is the first of a two-part primer on the genetics of the epilepsies within the Genetic Literacy Series of the Genetics Commission of the International League Against Epilepsy. In Part 1, we cover the foundations of epilepsy genetics including genetic epidemiology and the range of genetic variants that can affect the risk for developing epilepsy. We discuss various epidemiologic study designs that have been applied to the genetics of the epilepsies including population studies, which provide compelling evidence for a strong genetic contribution in many epilepsies. We discuss genetic risk factors varying in size, frequency, inheritance pattern, effect size, and phenotypic specificity, and provide examples of how genetic risk factors within the various categories increase the risk for epilepsy. We end by highlighting trends in epilepsy genetics including the increasing use of massive parallel sequencing technologies. Wiley Periodicals, Inc. © 2016 International League Against Epilepsy.

Heritability and Genetic Advance among Chili Pepper Genotypes for Heat Tolerance and Morphophysiological Characteristics

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Magaji G. Usman

2014-01-01

Full Text Available High temperature tolerance is an important component of adaptation to arid and semiarid cropping environment in chili pepper. Two experiments were carried out to study the genetic variability among chili pepper for heat tolerance and morphophysiological traits and to estimate heritability and genetic advance expected from selection. There was a highly significant variation among the genotypes in response to high temperature (CMT, photosynthesis rate, plant height, disease incidence, fruit length, fruit weight, number of fruits, and yield per plant. At 5% selection intensity, high genetic advance as percent of the mean (>20% was observed for CMT, photosynthesis rate, fruit length, fruit weight, number of fruits, and yield per plant. Similarly, high heritability (>60% was also observed indicating the substantial effect of additive gene more than the environmental effect. Yield per plant showed strong to moderately positive correlations (r=0.23–0.56 at phenotypic level while at genotypic level correlation coefficient ranged from 0.16 to 0.72 for CMT, plant height, fruit length, and number of fruits. Cluster analysis revealed eight groups and Group VIII recorded the highest CMT and yield. Group IV recorded 13 genotypes while Groups II, VII, and VIII recorded one each. The results showed that the availability of genetic variance could be useful for exploitation through selection for further breeding purposes.

The role of common genetic variants in atrial fibrillation

DEFF Research Database (Denmark)

Paludan-Muller, Christian; Svendsen, Jesper H.; Olesen, Morten S.

2016-01-01

lone AF, has a substantial genetic component. A number of genome-wide association studies (GWAS) have indicated that common genetic variants, more precisely the so called single-nucleotide polymorphisms (SNPs) are associated with AF. Presently more than 10 genomic regions have been identified using...

Short communication: Genetic characterization of digital cushion thickness.

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Oikonomou, G; Banos, G; Machado, V; Caixeta, L; Bicalho, R C

2014-01-01

Dairy cow lameness is a serious animal welfare issue. It is also a significant cause of economic losses, reducing reproductive efficiency and milk production and increasing culling rates. The digital cushion is a complex structure composed mostly of adipose tissue located underneath the distal phalanx and has recently been phenotypically associated with incidence of claw horn disruption lesions (CHDL); namely, sole ulcers and white line disease. The objective of this study was to characterize digital cushion thickness genetically and to investigate its association with body condition score (BCS), locomotion score (LOCO), CHDL, and milk production. Data were collected from 1 large closely monitored commercial dairy farm located in upstate New York; 923 dairy cows were used. Before trimming, the following data were collected by a member of the research team: BCS, cow height measurement, and LOCO. Presence or not of CHDL (sole ulcer or white line disease, or both) was recorded at trimming. Immediately after the cows were hoof trimmed, they underwent digital sonographic B-mode examination for the measurement of digital cushion thickness. Factors such as parity number, stage of lactation, calving date, mature-equivalent 305-d milk yield (ME305MY), and pedigree information were obtained from the farm's dairy management software (DairyCOMP 305; Valley Agricultural Software, Tulare, CA). Univariate animal models were used to obtain variance component estimations for each studied trait (CHDL, BCS, digital cushion thickness average, LOCO, height, and ME305MY) and a 6-variate analysis was conducted to estimate the genetic, residual, and phenotypic correlations between the studied traits. The heritability estimate of DCTA was 0.33±0.09, whereas a statistically significant genetic correlation was estimated between DCTA and CHDL (-0.60±0.29). Of the other genetic correlations, significant estimates were derived for BCS with LOCO (-0.49±0.19) and ME305MY (-0.48±0.20). Digital

Genetic and Psychosocial Predictors of Aggression: Variable Selection and Model Building With Component-Wise Gradient Boosting.

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Suchting, Robert; Gowin, Joshua L; Green, Charles E; Walss-Bass, Consuelo; Lane, Scott D

2018-01-01

Rationale : Given datasets with a large or diverse set of predictors of aggression, machine learning (ML) provides efficient tools for identifying the most salient variables and building a parsimonious statistical model. ML techniques permit efficient exploration of data, have not been widely used in aggression research, and may have utility for those seeking prediction of aggressive behavior. Objectives : The present study examined predictors of aggression and constructed an optimized model using ML techniques. Predictors were derived from a dataset that included demographic, psychometric and genetic predictors, specifically FK506 binding protein 5 (FKBP5) polymorphisms, which have been shown to alter response to threatening stimuli, but have not been tested as predictors of aggressive behavior in adults. Methods : The data analysis approach utilized component-wise gradient boosting and model reduction via backward elimination to: (a) select variables from an initial set of 20 to build a model of trait aggression; and then (b) reduce that model to maximize parsimony and generalizability. Results : From a dataset of N = 47 participants, component-wise gradient boosting selected 8 of 20 possible predictors to model Buss-Perry Aggression Questionnaire (BPAQ) total score, with R 2 = 0.66. This model was simplified using backward elimination, retaining six predictors: smoking status, psychopathy (interpersonal manipulation and callous affect), childhood trauma (physical abuse and neglect), and the FKBP5_13 gene (rs1360780). The six-factor model approximated the initial eight-factor model at 99.4% of R 2 . Conclusions : Using an inductive data science approach, the gradient boosting model identified predictors consistent with previous experimental work in aggression; specifically psychopathy and trauma exposure. Additionally, allelic variants in FKBP5 were identified for the first time, but the relatively small sample size limits generality of results and calls for

Genetic and environmental influences on non-specific neck pain in early adolescence: A classical twin study

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Ståhl, Minna K; El-Metwally, Ashraf A; Mikkelsson, Marja K; Salminen, Jouko J; Pulkkinen, Lea R; Rose, Richard J; Kaprio, Jaakko A

2012-01-01

Background Prevalence of neck pain has increased among adolescents. The origins of adult chronic neck pain may lie in late childhood, but for early prevention, more information is needed about its aetiology. We investigated the relative roles of genetic and environmental factors in early adolescent neck pain with a classic twin study. Methods Frequency of neck pain was assessed with a validated pain questionnaire in a population-based sample of nearly 1800 pairs of 11–12-year-old Finnish twins. Twin pair similarity for neck pain was quantified by polychoric correlations, and variance components were estimated with biometric structural equation modelling. Results Prevalence of neck pain reported at least once monthly was 38% and at least once weekly 16%, with no significant differences between gender or zygosity. A greater polychoric correlation in liability to neck pain was found in monozygotic (0.67) than for dizygotic pairs (0.38), suggesting strong genetic influences. Model-fitting indicated that 68% (95% CI 62 to 74) of the variation in liability to neck pain could be attributed to genetic effects, with the remainder attributed to unshared environmental effects. No evidence for sex-specific genetic effects or for sex differences in the magnitude of genetic effects was found. Conclusions Genetic and unique environmental factors seem to play the most important roles in liability to neck pain in early adolescence. Future research should be directed to identifying pathways for genetic influences on neck pain and in exploring effectiveness of interventions that target already identified environmental risk factors. PMID:23139100

Studies of genetics of yield and yield component characters in F2 ...

African Journals Online (AJOL)

Jane

2011-08-03

Aug 3, 2011 ... 1Department of Genetics and Plant Breeding, Faculty of Agriculture, Annamalai ... the F3's of the cross ADT 38 x ADT 37 for hundred seed weight and the F3's the cross ADT 38 x ADT 44 ...... Recombination in species crosses.

Abdominal obesity is strongly associated to blood pressure in young Mexicans.

Science.gov (United States)

Urquidez Romero, Rene; Murguía Romero, Miguel; Esparza Romero, Julián; Díaz Torres, Beatriz Araceli; Rodríguez Tadeo, Alejandra; Medrano Donlucas, Gabriel; Ramos Jiménez, Arnulfo; Wall Medrano, Abraham; Gallardo Ortíz, Itzell A; Tapia Pancardo, Diana C Tapia-Pancardo C; Méndez Cruz, A René; Jiménez Flores, J Rafael; Villalobos Molina, Rafael

2017-03-30

The objective of this study was to determine associations between abdominal obesity (AOb) and the other components of metabolic syndrome (MetS) in young Mexicans in a cross-sectional survey completed during a 4 year period. This cross-sectional study reports on components and prevalence of MetS by using Alberti et al. (16) criteria, as well as association between AOb and elevated blood pressure (BP) of 2,993 Mexican university students, ages 17 to 25 years (66% women) from central and northern Mexico, over a 4-year survey (2010-2013). The most prevalent MetS components in the total sample were low HDL-C concentration (43.6%) and AOb (41.1%). MetS prevalence was 11.8%, more men than women were classified with MetS (14.3% vs. 10.5%, p < 0.01). BP was the MetS component with the lowest prevalence (8.6%). A strong association between AOb and altered BP with in both men and women was found (OR 4.3, IC95% 2.5-7.4). Even BP was the component with the lowest prevalence, AOb was more strongly associated with it. This fact, could explain the prevalence of hypertension among young Mexican adults.

Multicollinearity in spatial genetics: separating the wheat from the chaff using commonality analyses.

Science.gov (United States)

Prunier, J G; Colyn, M; Legendre, X; Nimon, K F; Flamand, M C

2015-01-01

Direct gradient analyses in spatial genetics provide unique opportunities to describe the inherent complexity of genetic variation in wildlife species and are the object of many methodological developments. However, multicollinearity among explanatory variables is a systemic issue in multivariate regression analyses and is likely to cause serious difficulties in properly interpreting results of direct gradient analyses, with the risk of erroneous conclusions, misdirected research and inefficient or counterproductive conservation measures. Using simulated data sets along with linear and logistic regressions on distance matrices, we illustrate how commonality analysis (CA), a detailed variance-partitioning procedure that was recently introduced in the field of ecology, can be used to deal with nonindependence among spatial predictors. By decomposing model fit indices into unique and common (or shared) variance components, CA allows identifying the location and magnitude of multicollinearity, revealing spurious correlations and thus thoroughly improving the interpretation of multivariate regressions. Despite a few inherent limitations, especially in the case of resistance model optimization, this review highlights the great potential of CA to account for complex multicollinearity patterns in spatial genetics and identifies future applications and lines of research. We strongly urge spatial geneticists to systematically investigate commonalities when performing direct gradient analyses. © 2014 John Wiley & Sons Ltd.

Regulating genetic privacy in the online health information era.

Science.gov (United States)

Magnusson, Roger S

As the clinical implications of the genetic components of disease come to be better understood, there is likely to be a significant increase in the volume of genetic information held within clinical records. As patient health care records, in turn, come on-line as part of broader health information networks, there is likely to be considerable pressure in favour of special laws protecting genetic privacy. This paper reviews some of the privacy challenges posed by electronic health records, some government initiatives in this area, and notes the impact that developments in genetic testing will have upon the 'genetic content' of e-health records. Despite the sensitivity of genetic information, the paper argues against a policy of 'genetic exceptionalism', and its implications for genetic privacy laws.

The genetics of obesity.

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All definitions of the metabolic syndrome include some form of obesity as one of the possible features. Body mass index (BMI) has a known genetic component, currently estimated to account for about 70% of the population variance in weight status for non-syndromal obesity. Much research effort has be...

Heritable patterns of tooth decay in the permanent dentition: principal components and factor analyses.

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Shaffer, John R; Feingold, Eleanor; Wang, Xiaojing; Tcuenco, Karen T; Weeks, Daniel E; DeSensi, Rebecca S; Polk, Deborah E; Wendell, Steve; Weyant, Robert J; Crout, Richard; McNeil, Daniel W; Marazita, Mary L

2012-03-09

Dental caries is the result of a complex interplay among environmental, behavioral, and genetic factors, with distinct patterns of decay likely due to specific etiologies. Therefore, global measures of decay, such as the DMFS index, may not be optimal for identifying risk factors that manifest as specific decay patterns, especially if the risk factors such as genetic susceptibility loci have small individual effects. We used two methods to extract patterns of decay from surface-level caries data in order to generate novel phenotypes with which to explore the genetic regulation of caries. The 128 tooth surfaces of the permanent dentition were scored as carious or not by intra-oral examination for 1,068 participants aged 18 to 75 years from 664 biological families. Principal components analysis (PCA) and factor analysis (FA), two methods of identifying underlying patterns without a priori surface classifications, were applied to our data. The three strongest caries patterns identified by PCA recaptured variation represented by DMFS index (correlation, r = 0.97), pit and fissure surface caries (r = 0.95), and smooth surface caries (r = 0.89). However, together, these three patterns explained only 37% of the variability in the data, indicating that a priori caries measures are insufficient for fully quantifying caries variation. In comparison, the first pattern identified by FA was strongly correlated with pit and fissure surface caries (r = 0.81), but other identified patterns, including a second pattern representing caries of the maxillary incisors, were not representative of any previously defined caries indices. Some patterns identified by PCA and FA were heritable (h(2) = 30-65%, p = 0.043-0.006), whereas other patterns were not, indicating both genetic and non-genetic etiologies of individual decay patterns. This study demonstrates the use of decay patterns as novel phenotypes to assist in understanding the multifactorial nature of dental caries.

Reclassification of Mixed Oligoastrocytic Tumors Using a Genetically Integrated Diagnostic Approach

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Seong-Ik Kim

2018-01-01

Full Text Available Background Mixed gliomas, such as oligoastrocytomas (OA, anaplastic oligoastrocytomas, and glioblastomas (GBMs with an oligodendroglial component (GBMO are defined as tumors composed of a mixture of two distinct neoplastic cell types, astrocytic and oligodendroglial. Recently, mutations ATRX and TP53, and codeletion of 1p/19q are shown to be genetic hallmarks of astrocytic and oligodendroglial tumors, respectively. Subsequent molecular analyses of mixed gliomas preferred the reclassification to either oligodendroglioma or astrocytoma. This study was designed to apply genetically integrated diagnostic criteria to mixed gliomas and determine usefulness and prognostic value of new classification in Korean patients. Methods Fifty-eight cases of mixed OAs and GBMOs were retrieved from the pathology archives of Seoul National University Hospital from 2004 to 2015. Reclassification was performed according to genetic and immunohistochemical properties. Clinicopathological characteristics of each subgroup were evaluated. Overall survival was assessed and compared between subgroups. Results We could reclassify all mixed OAs and GBMOs into either astrocytic or oligodendroglial tumors. Notably, 29 GBMOs could be reclassified into 11 cases of GBM, IDH-mutant, 16 cases of GBM, IDH-wildtype, and two cases of anaplastic oligodendroglioma, IDH mutant. Overall survival was significantly different among these new groups (p<.001. Overall survival and progression-free survival were statistically better in gliomas with IDH mutation, ATRX mutation, no microscopic necrosis, and young patient age (cut off, 45 years old. Conclusions Our results strongly suggest that a genetically integrated diagnosis of glioma better reflects prognosis than former morphology-based methods.

Reaching a Consensus on the Definition of Genetic Literacy that Is Required from a Twenty-First-Century Citizen

Science.gov (United States)

Boerwinkel, Dirk Jan; Yarden, Anat; Waarlo, Arend Jan

2017-12-01

To determine what knowledge of genetics is needed for decision-making on genetic-related issues, a consensus-reaching approach was used. An international group of 57 experts, involved in teaching, studying, or developing genetic education and communication or working with genetic applications in medicine, agriculture, or forensics, answered the questions: "What knowledge of genetics is relevant to those individuals not professionally involved in science?" and "Why is this knowledge relevant?" The answers were classified in different knowledge components following the PISA 2015 science framework. During a workshop with the participants, the results were discussed and applied to seven cases in which genetic knowledge is relevant for decision-making. The analysis of these discussions resulted in a revised framework consisting of nine conceptual knowledge components, three sociocultural components, and four epistemic components. The framework can be used in curricular decisions; its open character allows for including new technologies and applications and facilitates comparisons of different cases.

THE EFFECT OF PHANTOM GROUPS ON GENETIC TREND

African Journals Online (AJOL)

Helena Theron

In an animal model evaluation of breeding values it is assumed that the base animals are all at the .... these values over the daughters of a sire reduces the stochastic component and represents a genetic ... To test whether the genetic trend is over- or underestimated, a regression model is fitted to the DYD ... parameter.

Grain Yield, Its Components, Genetic Diversity and Heritability in Chickpea (Cicer arietinum L.

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M. Kakaei

2015-09-01

Full Text Available The current research was carried out to investigate grain yield and components and their genetic diversity and heritability of some important agronomic traits, in 19 chickpea genotypes, based on a randomized complete block design with 3 replications in Research Field of Bu-Ali Sina University, Hamadan, Iran in 2011-2012 growing seasons. The ANOVA results showed that, there were highly significant differences (p < 0.01 among genotypes for the SPAD number, number of sub-branch per plant, pod number per plant, 100-kernel weight, grain yield, biological yield, and harvest index. The mean comparisons results indicated that the genotypes 14, 12, 4 and 19 (with 234.7, 240, 250.3 and 259.4 kilogram of grain yield per ha, respectively and the genotypes 18, 8, 15, and 6 (with 151.01, 167.6, 167.8 and 189 kilogram of grain yield per ha, respectively had the maximum and minimum economic yield, respectively. According to phonotypical correlation results, there were positive and significant (p < 0.01 correlations between grain yield and pod number per plant (0.623**, plant height (0.432**, harvest index (0.425** and biomass (0.349**. Step-wise regression indicated that the pod number per plant, harvest index, biomass, number of sub-branch per plant, and plant height were the most effective traits on economic yield and they explained 84.68 percent of the variation in economic yield. Furthermore, harvest index and seed number per plant had the maximum and minimum heritability, respectively, indicating that they could be hired as sources of variation for improving the grain yield and selecting superior genotypes.

Ascaroside expression in Caenorhabditis elegans is strongly dependent on diet and developmental stage.

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Fatma Kaplan

2011-03-01

Full Text Available The ascarosides form a family of small molecules that have been isolated from cultures of the nematode Caenorhabditis elegans. They are often referred to as "dauer pheromones" because most of them induce formation of long-lived and highly stress resistant dauer larvae. More recent studies have shown that ascarosides serve additional functions as social signals and mating pheromones. Thus, ascarosides have multiple functions. Until now, it has been generally assumed that ascarosides are constitutively expressed during nematode development.Cultures of C. elegans were developmentally synchronized on controlled diets. Ascarosides released into the media, as well as stored internally, were quantified by LC/MS. We found that ascaroside biosynthesis and release were strongly dependent on developmental stage and diet. The male attracting pheromone was verified to be a blend of at least four ascarosides, and peak production of the two most potent mating pheromone components, ascr#3 and asc#8 immediately preceded or coincided with the temporal window for mating. The concentration of ascr#2 increased under starvation conditions and peaked during dauer formation, strongly supporting ascr#2 as the main population density signal (dauer pheromone. After dauer formation, ascaroside production largely ceased and dauer larvae did not release any ascarosides. These findings show that both total ascaroside production and the relative proportions of individual ascarosides strongly correlate with these compounds' stage-specific biological functions.Ascaroside expression changes with development and environmental conditions. This is consistent with multiple functions of these signaling molecules. Knowledge of such differential regulation will make it possible to associate ascaroside production to gene expression profiles (transcript, protein or enzyme activity and help to determine genetic pathways that control ascaroside biosynthesis. In conjunction with findings

Do species conservation assessments capture genetic diversity?

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Malin C. Rivers

2014-12-01

Full Text Available The best known system for classifying threat status of species, the IUCN Red List, currently lacks explicit considerations of genetic diversity, and consequently may not account for potential adaptation of species to future environmental change. To address this gap, we integrate range-wide genetic analysis with IUCN Red List assessments.We calculated the loss of genetic diversity under simulated range loss for species of Delonix (Leguminosae. Simulated range loss involved random loss of populations and was intended to model ongoing habitat destruction. We found a strong relationship between loss of genetic diversity and range. Moreover, we found correspondence between levels of genetic diversity and thresholds for ‘non-threatened’ versus ‘threatened’ IUCN Red List categories.Our results support the view that current threat thresholds of the IUCN Red List criteria reflect genetic diversity, and hence evolutionary potential; although the genetic diversity distinction between threatened categories was less evident. Thus, by supplementing conventional conservation assessments with genetic data, new insights into the biological robustness of IUCN Red List assessments for targeted conservation initiatives can be achieved. Keywords: Conservation assessment, Conservation genetics, Extinction risk, Genetic diversity, IUCN Red List, Range

Is the strongly penetrating component a sign of the strangelet passage through matter?

International Nuclear Information System (INIS)

Gladysz-Dziadus, E.; Wlodarczyk, Z.

1997-01-01

We investigate the possible connection between the very penetrating component, frequently accompanying the cosmic-ray exotic phenomena, and the hypothesis of the formation of strangelets, in the process of strangeness distillation, being the last stage of the evolution of the quark matter droplet. We find that the many-maxima long-range cascades observed in the homogeneous lead emulsion chambers of the Pamir and Chacaltaya experiments can be produced in the process of strangelet penetration through the apparatus. (author)

Perils of parsimony: properties of reduced-rank estimates of genetic covariance matrices.

Science.gov (United States)

Meyer, Karin; Kirkpatrick, Mark

2008-10-01

Eigenvalues and eigenvectors of covariance matrices are important statistics for multivariate problems in many applications, including quantitative genetics. Estimates of these quantities are subject to different types of bias. This article reviews and extends the existing theory on these biases, considering a balanced one-way classification and restricted maximum-likelihood estimation. Biases are due to the spread of sample roots and arise from ignoring selected principal components when imposing constraints on the parameter space, to ensure positive semidefinite estimates or to estimate covariance matrices of chosen, reduced rank. In addition, it is shown that reduced-rank estimators that consider only the leading eigenvalues and -vectors of the "between-group" covariance matrix may be biased due to selecting the wrong subset of principal components. In a genetic context, with groups representing families, this bias is inverse proportional to the degree of genetic relationship among family members, but is independent of sample size. Theoretical results are supplemented by a simulation study, demonstrating close agreement between predicted and observed bias for large samples. It is emphasized that the rank of the genetic covariance matrix should be chosen sufficiently large to accommodate all important genetic principal components, even though, paradoxically, this may require including a number of components with negligible eigenvalues. A strategy for rank selection in practical analyses is outlined.

Genetically modified foods and allergy.

Science.gov (United States)

Lee, T H; Ho, H K; Leung, T F

2017-06-01

2015 marked the 25th anniversary of the commercial use and availability of genetically modified crops. The area of planted biotech crops cultivated globally occupies a cumulative two billion hectares, equivalent to twice the land size of China or the United States. Foods derived from genetically modified plants are widely consumed in many countries and genetically modified soybean protein is extensively used in processed foods throughout the industrialised countries. Genetically modified food technology offers a possible solution to meet current and future challenges in food and medicine. Yet there is a strong undercurrent of anxiety that genetically modified foods are unsafe for human consumption, sometimes fuelled by criticisms based on little or no firm evidence. This has resulted in some countries turning away food destined for famine relief because of the perceived health risks of genetically modified foods. The major concerns include their possible allergenicity and toxicity despite the vigorous testing of genetically modified foods prior to marketing approval. It is imperative that scientists engage the public in a constructive evidence-based dialogue to address these concerns. At the same time, improved validated ways to test the safety of new foods should be developed. A post-launch strategy should be established routinely to allay concerns. Mandatory labelling of genetically modified ingredients should be adopted for the sake of transparency. Such ingredient listing and information facilitate tracing and recall if required.

Using genetic information while protecting the privacy of the soul.

Science.gov (United States)

Moor, J H

1999-01-01

Computing plays an important role in genetics (and vice versa). Theoretically, computing provides a conceptual model for the function and malfunction of our genetic machinery. Practically, contemporary computers and robots equipped with advanced algorithms make the revelation of the complete human genome imminent--computers are about to reveal our genetic souls for the first time. Ethically, computers help protect privacy by restricting access in sophisticated ways to genetic information. But the inexorable fact that computers will increasingly collect, analyze, and disseminate abundant amounts of genetic information made available through the genetic revolution, not to mention that inexpensive computing devices will make genetic information gathering easier, underscores the need for strong and immediate privacy legislation.

Diagnosing a Strong-Fault Model by Conflict and Consistency

Directory of Open Access Journals (Sweden)

Wenfeng Zhang

2018-03-01

Full Text Available The diagnosis method for a weak-fault model with only normal behaviors of each component has evolved over decades. However, many systems now demand a strong-fault models, the fault modes of which have specific behaviors as well. It is difficult to diagnose a strong-fault model due to its non-monotonicity. Currently, diagnosis methods usually employ conflicts to isolate possible fault and the process can be expedited when some observed output is consistent with the model’s prediction where the consistency indicates probably normal components. This paper solves the problem of efficiently diagnosing a strong-fault model by proposing a novel Logic-based Truth Maintenance System (LTMS with two search approaches based on conflict and consistency. At the beginning, the original a strong-fault model is encoded by Boolean variables and converted into Conjunctive Normal Form (CNF. Then the proposed LTMS is employed to reason over CNF and find multiple minimal conflicts and maximal consistencies when there exists fault. The search approaches offer the best candidate efficiency based on the reasoning result until the diagnosis results are obtained. The completeness, coverage, correctness and complexity of the proposals are analyzed theoretically to show their strength and weakness. Finally, the proposed approaches are demonstrated by applying them to a real-world domain—the heat control unit of a spacecraft—where the proposed methods are significantly better than best first and conflict directly with A* search methods.

Diagnosing a Strong-Fault Model by Conflict and Consistency.

Science.gov (United States)

Zhang, Wenfeng; Zhao, Qi; Zhao, Hongbo; Zhou, Gan; Feng, Wenquan

2018-03-29

The diagnosis method for a weak-fault model with only normal behaviors of each component has evolved over decades. However, many systems now demand a strong-fault models, the fault modes of which have specific behaviors as well. It is difficult to diagnose a strong-fault model due to its non-monotonicity. Currently, diagnosis methods usually employ conflicts to isolate possible fault and the process can be expedited when some observed output is consistent with the model's prediction where the consistency indicates probably normal components. This paper solves the problem of efficiently diagnosing a strong-fault model by proposing a novel Logic-based Truth Maintenance System (LTMS) with two search approaches based on conflict and consistency. At the beginning, the original a strong-fault model is encoded by Boolean variables and converted into Conjunctive Normal Form (CNF). Then the proposed LTMS is employed to reason over CNF and find multiple minimal conflicts and maximal consistencies when there exists fault. The search approaches offer the best candidate efficiency based on the reasoning result until the diagnosis results are obtained. The completeness, coverage, correctness and complexity of the proposals are analyzed theoretically to show their strength and weakness. Finally, the proposed approaches are demonstrated by applying them to a real-world domain-the heat control unit of a spacecraft-where the proposed methods are significantly better than best first and conflict directly with A* search methods.

Ancient DNA Reveals That the Genetic Structure of the Northern Han Chinese Was Shaped Prior to 3,000 Years Ago

Science.gov (United States)

Zhang, Quan-Chao; Li, Hong-Jie; Cui, Ying-Qiu; Xu, Zhi; Jin, Li; Zhou, Hui; Zhu, Hong

2015-01-01

The Han Chinese are the largest ethnic group in the world, and their origins, development, and expansion are complex. Many genetic studies have shown that Han Chinese can be divided into two distinct groups: northern Han Chinese and southern Han Chinese. The genetic history of the southern Han Chinese has been well studied. However, the genetic history of the northern Han Chinese is still obscure. In order to gain insight into the genetic history of the northern Han Chinese, 89 human remains were sampled from the Hengbei site which is located in the Central Plain and dates back to a key transitional period during the rise of the Han Chinese (approximately 3,000 years ago). We used 64 authentic mtDNA data obtained in this study, 27 Y chromosome SNP data profiles from previously studied Hengbei samples, and genetic datasets of the current Chinese populations and two ancient northern Chinese populations to analyze the relationship between the ancient people of Hengbei and present-day northern Han Chinese. We used a wide range of population genetic analyses, including principal component analyses, shared mtDNA haplotype analyses, and geographic mapping of maternal genetic distances. The results show that the ancient people of Hengbei bore a strong genetic resemblance to present-day northern Han Chinese and were genetically distinct from other present-day Chinese populations and two ancient populations. These findings suggest that the genetic structure of northern Han Chinese was already shaped 3,000 years ago in the Central Plain area. PMID:25938511

Unnatural reactive amino acid genetic code additions

Energy Technology Data Exchange (ETDEWEB)

Deiters, Alexander; Cropp, T. Ashton; Chin, Jason W.; Anderson, Christopher J.; Schultz, Peter G.

2017-10-25

This invention provides compositions and methods for producing translational components that expand the number of genetically encoded amino acids in eukaryotic cells. The components include orthogonal tRNAs, orthogonal aminoacyl-tRNA synthetases, orthogonal pairs of tRNAs/synthetases and unnatural amino acids. Proteins and methods of producing proteins with unnatural amino acids in eukaryotic cells are also provided.

Whole genome population genetics analysis of Sudanese goats identifies regions harboring genes associated with major traits.

Science.gov (United States)

Rahmatalla, Siham A; Arends, Danny; Reissmann, Monika; Said Ahmed, Ammar; Wimmers, Klaus; Reyer, Henry; Brockmann, Gudrun A

2017-10-23

Sudan is endowed with a variety of indigenous goat breeds which are used for meat and milk production and which are well adapted to the local environment. The aim of the present study was to determine the genetic diversity and relationship within and between the four main Sudanese breeds of Nubian, Desert, Taggar and Nilotic goats. Using the 50 K SNP chip, 24 animals of each breed were genotyped. More than 96% of high quality SNPs were polymorphic with an average minor allele frequency of 0.3. In all breeds, no significant difference between observed (0.4) and expected (0.4) heterozygosity was found and the inbreeding coefficients (F IS ) did not differ from zero. F st coefficients for the genetic distance between breeds also did not significantly deviate from zero. In addition, the analysis of molecular variance revealed that 93% of the total variance in the examined population can be explained by differences among individuals, while only 7% result from differences between the breeds. These findings provide evidence for high genetic diversity and little inbreeding within breeds on one hand, and low diversity between breeds on the other hand. Further examinations using Nei's genetic distance and STRUCTURE analysis clustered Taggar goats distinct from the other breeds. In a principal component (PC) analysis, PC1 could separate Taggar, Nilotic and a mix of Nubian and Desert goats into three groups. The SNPs that contributed strongly to PC1 showed high F st values in Taggar goat versus the other goat breeds. PCA allowed us to identify target genomic regions which contain genes known to influence growth, development, bone formation and the immune system. The information on the genetic variability and diversity in this study confirmed that Taggar goat is genetically different from the other goat breeds in Sudan. The SNPs identified by the first principal components show high F st values in Taggar goat and allowed to identify candidate genes which can be used in the

Genetics of serum carotenoid concentrations and their correlation with obesity-related traits in Mexican American children.

Science.gov (United States)

Farook, Vidya S; Reddivari, Lavanya; Mummidi, Srinivas; Puppala, Sobha; Arya, Rector; Lopez-Alvarenga, Juan Carlos; Fowler, Sharon P; Chittoor, Geetha; Resendez, Roy G; Kumar, Birunda Mohan; Comuzzie, Anthony G; Curran, Joanne E; Lehman, Donna M; Jenkinson, Christopher P; Lynch, Jane L; DeFronzo, Ralph A; Blangero, John; Hale, Daniel E; Duggirala, Ravindranath; Vanamala, Jairam Kp

2017-07-01

�-carotene and BMI (-0.27), WC (-0.30), and HDL cholesterol (0.31) after accounting for multiple comparisons. None of the environmental correlations were significant. Conclusions: The findings from this study suggest that the serum carotenoid concentrations were under strong additive genetic influences based on variance components analyses, and that the common genetic factors may influence β-carotene and obesity and lipid traits in MA children. © 2017 American Society for Nutrition.

Genetic parameters for reproduction rate in the Tygerhoek Merino ...

African Journals Online (AJOL)

Dolling, 1963; Lewer, Rae & Wickham, 1983). Genetic. Number of lambing opportunities correlations involving EclEm and Ld/Lb, that showed. 2. 3. 4. 5 little genetic variation (Cloete &Heydenrych, 1987)were. Item particularly unstable. Negative between-sire variance. First set of data components prevented the estimation of ...

Genetic Variation in Complement Component 2 of the Classical Complement Pathway is Associated with Increased Mortality and Infection: A Study of 627 Trauma Patients

Science.gov (United States)

Morris, John A.; Francois, Cedric; Olson, Paul K.; Cotton, Bryan A.; Summar, Marshall; Jenkins, Judith M.; Norris, Patrick R.; Moore, Jason H.; Williams, Anna E.; McNew, Brent S.; Canter, Jeffrey A.

2009-01-01

Trauma is a disease of inflammation. Complement Component 2 (C2) is a protease involved in activation of complement through the classical pathway and has been implicated in a variety of chronic inflammatory diseases. We hypothesized that genetic variation in C2 (E318D) identifies a high-risk subgroup of trauma patients reflecting increased mortality and infection (Ventilator associated pneumonia: VAP). Consequently, genetic variation in C2 may stratify patient risk and illuminate underlying mechanisms for therapeutic intervention. Methods DNA samples from 702 trauma patients were genotyped for C2 E318D and linked with covariates (age: mean 42.8 years, gender: 74% male, ethnicity: 80% Caucasian, mechanism: 84% blunt, ISS: mean 25.0, admission lactate: mean 3.13 mEq/L) and outcomes: mortality 9.9% and VAP: 18.5%. VAP was defined by quantitative bronchoalveolar lavage (>104). Multivariate regression determined the relationship of genotype and covariates to risk of death and VAP. However, patients with ISS ≥ 45 were excluded from the multivariate analysis, as magnitude of injury overwhelms genetics and covariates in determining outcome. Results 52 patients (8.3%) had the high-risk heterozygous genotype, associated with a significant increase in mortality and VAP. Conclusion In 702 trauma patients, 8.3% had a high-risk genetic variation in C2 associated with increased mortality (OR=2.65) and infection (OR=2.00). This variation: 1) Identifies a previously unknown high risk group for infection and mortality; 2) Can be determined on admission; 3) May provide opportunity for early therapeutic intervention; and 4) Requires validation in a distinct cohort of patients. PMID:19430225

Stochastic modelling of shifts in allele frequencies reveals a strongly polygynous mating system in the re-introduced Asiatic wild ass.

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Renan, Sharon; Greenbaum, Gili; Shahar, Naama; Templeton, Alan R; Bouskila, Amos; Bar-David, Shirli

2015-04-01

Small populations are prone to loss of genetic variation and hence to a reduction in their evolutionary potential. Therefore, studying the mating system of small populations and its potential effects on genetic drift and genetic diversity is of high importance for their viability assessments. The traditional method for studying genetic mating systems is paternity analysis. Yet, as small populations are often rare and elusive, the genetic data required for paternity analysis are frequently unavailable. The endangered Asiatic wild ass (Equus hemionus), like all equids, displays a behaviourally polygynous mating system; however, the level of polygyny has never been measured genetically in wild equids. Combining noninvasive genetic data with stochastic modelling of shifts in allele frequencies, we developed an alternative approach to paternity analysis for studying the genetic mating system of the re-introduced Asiatic wild ass in the Negev Desert, Israel. We compared the shifts in allele frequencies (as a measure of genetic drift) that have occurred in the wild ass population since re-introduction onset to simulated scenarios under different proportions of mating males. We revealed a strongly polygynous mating system in which less than 25% of all males participate in the mating process each generation. This strongly polygynous mating system and its potential effect on the re-introduced population's genetic diversity could have significant consequences for the long-term persistence of the population in the Negev. The stochastic modelling approach and the use of allele-frequency shifts can be further applied to systems that are affected by genetic drift and for which genetic data are limited. © 2015 John Wiley & Sons Ltd.

EXPLOITATION OF GENETIC POTENTIAL OF SWEETPOTATO FOR ...

African Journals Online (AJOL)

USER

Sweetpotato (Ipomoea batatas Lam) is a staple food globally, but it has remained ... The strong positive genetic association between dry matter and starch .... Storage roots selected were approximately 3 cm ...... gelatinisation properties.

Feature selection for neural network based defect classification of ceramic components using high frequency ultrasound.

Science.gov (United States)

Kesharaju, Manasa; Nagarajah, Romesh

2015-09-01

The motivation for this research stems from a need for providing a non-destructive testing method capable of detecting and locating any defects and microstructural variations within armour ceramic components before issuing them to the soldiers who rely on them for their survival. The development of an automated ultrasonic inspection based classification system would make possible the checking of each ceramic component and immediately alert the operator about the presence of defects. Generally, in many classification problems a choice of features or dimensionality reduction is significant and simultaneously very difficult, as a substantial computational effort is required to evaluate possible feature subsets. In this research, a combination of artificial neural networks and genetic algorithms are used to optimize the feature subset used in classification of various defects in reaction-sintered silicon carbide ceramic components. Initially wavelet based feature extraction is implemented from the region of interest. An Artificial Neural Network classifier is employed to evaluate the performance of these features. Genetic Algorithm based feature selection is performed. Principal Component Analysis is a popular technique used for feature selection and is compared with the genetic algorithm based technique in terms of classification accuracy and selection of optimal number of features. The experimental results confirm that features identified by Principal Component Analysis lead to improved performance in terms of classification percentage with 96% than Genetic algorithm with 94%. Copyright © 2015 Elsevier B.V. All rights reserved.

The genetic validation of heterogeneity in schizophrenia.

Science.gov (United States)

Tsutsumi, Atsushi; Glatt, Stephen J; Kanazawa, Tetsufumi; Kawashige, Seiya; Uenishi, Hiroyuki; Hokyo, Akira; Kaneko, Takao; Moritani, Makiko; Kikuyama, Hiroki; Koh, Jun; Matsumura, Hitoshi; Yoneda, Hiroshi

2011-10-07

Schizophrenia is a heritable disorder, however clear genetic architecture has not been detected. To overcome this state of uncertainty, the SZGene database has been established by including all published case-control genetic association studies appearing in peer-reviewed journals. In the current study, we aimed to determine if genetic variants strongly suggested by SZGene are associated with risk of schizophrenia in our case-control samples of Japanese ancestry. In addition, by employing the additive model for aggregating the effect of seven variants, we aimed to verify the genetic heterogeneity of schizophrenia diagnosed by an operative diagnostic manual, the DSM-IV. Each positively suggested genetic polymorphism was ranked according to its p-value, then the seven top-ranked variants (p Japanese population. It is also important to aggregate the updated positive variants in the SZGene database when the replication work is conducted.

Nurses' knowledge and educational needs regarding genetics.

Science.gov (United States)

Seven, Memnun; Akyüz, Aygül; Elbüken, Burcu; Skirton, Heather; Öztürk, Hatice

2015-03-01

Nurses now require a basic knowledge of genetics to provide patient care in a range of settings. To determine Turkish registered nurses' current knowledge and educational needs in relation to genetics. A descriptive, cross-sectional study. Turkish registered nurses working in a university hospital in Turkey were recruited. All registered nurses were invited to participate and 175 completed the study. The survey instrument, basic knowledge of health genetics, confidence in knowledge and the nurses' need for genetics education were used to collect data. The majority (81.1%, n=142) of participants indicated that genetics was not taught during their degree program, although 53.1% to 96% of respondents felt confident in defining different genetic concepts. The average genetics knowledge score was 6.89±1.99 of a possible 11 (range 0-11). The majority (70.3%) expressed a strong wish to attend a continuing nursing education program in genetics. The study shows that although Turkish nurses are not sufficiently knowledgeable to apply genetics in practice, they are willing to have more education to support their care of patients. Nurses need to have more education related to genetics in accordance with advances in human genetics to optimize health care. Copyright © 2014 Elsevier Ltd. All rights reserved.

The genetic variance but not the genetic covariance of life-history traits changes towards the north in a time-constrained insect.

Science.gov (United States)

Sniegula, Szymon; Golab, Maria J; Drobniak, Szymon M; Johansson, Frank

2018-03-22

Seasonal time constraints are usually stronger at higher than lower latitudes and can exert strong selection on life-history traits and the correlations among these traits. To predict the response of life-history traits to environmental change along a latitudinal gradient, information must be obtained about genetic variance in traits and also genetic correlation between traits, that is the genetic variance-covariance matrix, G. Here, we estimated G for key life-history traits in an obligate univoltine damselfly that faces seasonal time constraints. We exposed populations to simulated native temperatures and photoperiods and common garden environmental conditions in a laboratory set-up. Despite differences in genetic variance in these traits between populations (lower variance at northern latitudes), there was no evidence for latitude-specific covariance of the life-history traits. At simulated native conditions, all populations showed strong genetic and phenotypic correlations between traits that shaped growth and development. The variance-covariance matrix changed considerably when populations were exposed to common garden conditions compared with the simulated natural conditions, showing the importance of environmentally induced changes in multivariate genetic structure. Our results highlight the importance of estimating variance-covariance matrixes in environments that mimic selection pressures and not only trait variances or mean trait values in common garden conditions for understanding the trait evolution across populations and environments. © 2018 European Society For Evolutionary Biology. Journal of Evolutionary Biology © 2018 European Society For Evolutionary Biology.

Metal binding by food components

DEFF Research Database (Denmark)

Tang, Ning

for zinc binding by the investigated amino acids, peptides and proteins. The thiol group or imidazole group containing amino acids, peptides and proteins which exhibited strong zinc binding ability were further selected for interacting with zinc salts in relation to zinc absorption. The interactions...... between the above selected food components and zinc citrate or zinc phytate will lead to the enhanced solubility of zinc citrate or zinc phytate. The main driving force for this observed solubility enhancement is the complex formation between zinc and investigated food components as revealed by isothermal...... titration calorimetry and quantum mechanical calculations. This is due to the zinc binding affinity of the relatively softer ligands (investigated food components) will become much stronger than citrate or phytate when they present together in aqueous solution. This mechanism indicates these food components...

A large-scale genetic analysis reveals a strong contribution of the HLA class II region to giant cell arteritis susceptibility.

Science.gov (United States)

Carmona, F David; Mackie, Sarah L; Martín, Jose-Ezequiel; Taylor, John C; Vaglio, Augusto; Eyre, Stephen; Bossini-Castillo, Lara; Castañeda, Santos; Cid, Maria C; Hernández-Rodríguez, José; Prieto-González, Sergio; Solans, Roser; Ramentol-Sintas, Marc; González-Escribano, M Francisca; Ortiz-Fernández, Lourdes; Morado, Inmaculada C; Narváez, Javier; Miranda-Filloy, José A; Beretta, Lorenzo; Lunardi, Claudio; Cimmino, Marco A; Gianfreda, Davide; Santilli, Daniele; Ramirez, Giuseppe A; Soriano, Alessandra; Muratore, Francesco; Pazzola, Giulia; Addimanda, Olga; Wijmenga, Cisca; Witte, Torsten; Schirmer, Jan H; Moosig, Frank; Schönau, Verena; Franke, Andre; Palm, Øyvind; Molberg, Øyvind; Diamantopoulos, Andreas P; Carette, Simon; Cuthbertson, David; Forbess, Lindsy J; Hoffman, Gary S; Khalidi, Nader A; Koening, Curry L; Langford, Carol A; McAlear, Carol A; Moreland, Larry; Monach, Paul A; Pagnoux, Christian; Seo, Philip; Spiera, Robert; Sreih, Antoine G; Warrington, Kenneth J; Ytterberg, Steven R; Gregersen, Peter K; Pease, Colin T; Gough, Andrew; Green, Michael; Hordon, Lesley; Jarrett, Stephen; Watts, Richard; Levy, Sarah; Patel, Yusuf; Kamath, Sanjeet; Dasgupta, Bhaskar; Worthington, Jane; Koeleman, Bobby P C; de Bakker, Paul I W; Barrett, Jennifer H; Salvarani, Carlo; Merkel, Peter A; González-Gay, Miguel A; Morgan, Ann W; Martín, Javier

2015-04-02

We conducted a large-scale genetic analysis on giant cell arteritis (GCA), a polygenic immune-mediated vasculitis. A case-control cohort, comprising 1,651 case subjects with GCA and 15,306 unrelated control subjects from six different countries of European ancestry, was genotyped by the Immunochip array. We also imputed HLA data with a previously validated imputation method to perform a more comprehensive analysis of this genomic region. The strongest association signals were observed in the HLA region, with rs477515 representing the highest peak (p = 4.05 × 10(-40), OR = 1.73). A multivariate model including class II amino acids of HLA-DRβ1 and HLA-DQα1 and one class I amino acid of HLA-B explained most of the HLA association with GCA, consistent with previously reported associations of classical HLA alleles like HLA-DRB1(∗)04. An omnibus test on polymorphic amino acid positions highlighted DRβ1 13 (p = 4.08 × 10(-43)) and HLA-DQα1 47 (p = 4.02 × 10(-46)), 56, and 76 (both p = 1.84 × 10(-45)) as relevant positions for disease susceptibility. Outside the HLA region, the most significant loci included PTPN22 (rs2476601, p = 1.73 × 10(-6), OR = 1.38), LRRC32 (rs10160518, p = 4.39 × 10(-6), OR = 1.20), and REL (rs115674477, p = 1.10 × 10(-5), OR = 1.63). Our study provides evidence of a strong contribution of HLA class I and II molecules to susceptibility to GCA. In the non-HLA region, we confirmed a key role for the functional PTPN22 rs2476601 variant and proposed other putative risk loci for GCA involved in Th1, Th17, and Treg cell function. Copyright © 2015 The American Society of Human Genetics. Published by Elsevier Inc. All rights reserved.

Genetic Dissection of Anopheles gambiae Gut Epithelial Responses to Serratia marcescens

Science.gov (United States)

Stathopoulos, Stavros; Neafsey, Daniel E.; Lawniczak, Mara K. N.; Muskavitch, Marc A. T.; Christophides, George K.

2014-01-01

Genetic variation in the mosquito Anopheles gambiae profoundly influences its ability to transmit malaria. Mosquito gut bacteria are shown to influence the outcome of infections with Plasmodium parasites and are also thought to exert a strong drive on genetic variation through natural selection; however, a link between antibacterial effects and genetic variation is yet to emerge. Here, we combined SNP genotyping and expression profiling with phenotypic analyses of candidate genes by RNAi-mediated silencing and 454 pyrosequencing to investigate this intricate biological system. We identified 138 An. gambiae genes to be genetically associated with the outcome of Serratia marcescens infection, including the peptidoglycan recognition receptor PGRPLC that triggers activation of the antibacterial IMD/REL2 pathway and the epidermal growth factor receptor EGFR. Silencing of three genes encoding type III fibronectin domain proteins (FN3Ds) increased the Serratia load and altered the gut microbiota composition in favor of Enterobacteriaceae. These data suggest that natural genetic variation in immune-related genes can shape the bacterial population structure of the mosquito gut with high specificity. Importantly, FN3D2 encodes a homolog of the hypervariable pattern recognition receptor Dscam, suggesting that pathogen-specific recognition may involve a broader family of immune factors. Additionally, we showed that silencing the gene encoding the gustatory receptor Gr9 that is also associated with the Serratia infection phenotype drastically increased Serratia levels. The Gr9 antibacterial activity appears to be related to mosquito feeding behavior and to mostly rely on changes of neuropeptide F expression, together suggesting a behavioral immune response following Serratia infection. Our findings reveal that the mosquito response to oral Serratia infection comprises both an epithelial and a behavioral immune component. PMID:24603764

Characterization of genetic diversity of bird-of-paradise accessions

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Alessandro Aparecido Brito dos Santos

2018-04-01

Full Text Available This study aimed to characterize genetic diversity in the bird-of-paradise (Strelitzia reginae collection at the Universidade do Estado de Mato Grosso Carlos Alberto Reyes Maldonado (UNEMAT by estimating genetic divergence among genotypes based on agronomic characteristics. Seven agronomic characters were evaluated with average Euclidean distance. The UPGMA (Unweighted Pair Group Method with Arithmetic Mean hierarchical clustering method was used between groups, as well as Tocher’s optimization clustering method and principal component analysis (PCA, in order to classify the genotypes with maximum similarity between groups. Measures of genetic dissimilarity with average Euclidean distance verified the existence of genetic variability among accessions since the amplitude of dissimilarity values ranged from 1.09 to 36.97. Tocher’s clustering method verified the formation of two distinct groups. UPGMA hierarchical clustering, based on the dissimilarity matrix, verified the formation of three groups with 30% cutoff point. Based on the main components analysis, we verified genetic divergence between the bird-of-paradise accessions in the UNEMAT Collection. The most promising combinations for future crosses in breeding programs comprise accessions 1, 11, and 23 and accession 1 as the most divergent among the accessions evaluated.

Itinerant Ferromagnetism in a Polarized Two-Component Fermi Gas

DEFF Research Database (Denmark)

Massignan, Pietro; Yu, Zhenhua; Bruun, Georg

2013-01-01

We analyze when a repulsively interacting two-component Fermi gas becomes thermodynamically unstable against phase separation. We focus on the strongly polarized limit, where the free energy of the homogeneous mixture can be calculated accurately in terms of well-defined quasiparticles, the repul......We analyze when a repulsively interacting two-component Fermi gas becomes thermodynamically unstable against phase separation. We focus on the strongly polarized limit, where the free energy of the homogeneous mixture can be calculated accurately in terms of well-defined quasiparticles...

Malignant renal cysts: Diagnostic performance and strong predictors at MDCT

International Nuclear Information System (INIS)

Kim, Dae Yoon; Kim, Jeong Kon; Cho, Kyoung-Sik; Min, Gyeong-Eun; Ahn, Han-Jong

2010-01-01

Background: Utilization of multidetector-row CT (MDCT) is anticipated to improve the diagnostic accuracy and reliability for determining malignant cysts. Purpose: To assess the diagnostic accuracy, interobserver agreement, benefit of consensus reading, and strong predictors of malignancy in determining malignant cystic renal masses at MDCT. Material and Methods: Two radiologists independently rated the probability of malignancy at MDCT in 72 benign and 53 malignant cysts. The accuracy and interobserver agreement for determining malignant cysts were evaluated. The strong predictors of malignancy were determined, and in patients with interobserver disagreement for determining malignant cysts, consensus readings were performed. Results: Az value of the two readers was 0.905-0.936 and the sensitivity and specificity were 85-89% and 83-93%, respectively. The overall interobserver agreement for determining the malignant cyst was good as the κ value was 0.696 (% agreement, 61% (76/125)). Thickened irregular wall, thickened irregular septa, and enhancing soft tissue component were strong predictors for malignancy with both readers. In the 17 patients with interobserver disagreement for determining malignant cysts, the sensitivity was improved from 38-63% to 89% by the consensus reading. Conclusion: At MDCT, some false negative decisions for determining malignant cysts can be corrected by consensus reading, and thickened irregular septa, thickened irregular wall, and enhancing soft tissue component are the strong predictors of malignant cysts

Characterization of the triple-component linoleic acid isomerase in Lactobacillus plantarum ZS2058 by genetic manipulation.

Science.gov (United States)

Yang, B; Qi, H; Gu, Z; Zhang, H; Chen, W; Chen, H; Chen, Y Q

2017-11-01

To assess the mechanism for conjugated linoleic acid (CLA) production in Lactobacillus plantarum ZS2058. CLA has attracted great interests for decades due to its health-associated benefits including anticancer, anti-atherogenic, anti-obesity and modulation of the immune system. A number of microbial CLA producers were widely reported including lactic acid bacteria. Lactobacillus plantarum ZS2058, an isolate from Chinese traditional fermented food, could convert LA to CLA with various intermediates. To characterize the genetic determinants for generating CLA, a cre-lox-based system was utilized to delete the genes encoding myosin cross-reactive antigen (MCRA), short-chain dehydrogenase/oxidoreductase (DH) and acetoacetate decarboxylase (DC) in Lact. plantarum ZS2058, respectively. Neither intermediate was detected in the corresponding gene deletion mutant. Meanwhile all those mutants could recover the ability to convert linoleic acid to CLA when the corresponding gene was completed. The results indicated that CLA production was a multiple-step reaction catalysed by triple-component linoleate isomerase system encoded by mcra, dh and dc. Multicomponent linoleic acid isomerase provided important results for illustration unique mechanism for CLA production in Lact. plantarum ZS2058. Lactobacilli with CLA production ability offer novel opportunities for functional food development. © 2017 The Society for Applied Microbiology.

Quantifying introgression risk with realistic population genetics

OpenAIRE

Ghosh, Atiyo; Meirmans, Patrick G.; Haccou, Patsy

2012-01-01

Introgression is the permanent incorporation of genes from the genome of one population into another. This can have severe consequences, such as extinction of endemic species, or the spread of transgenes. Quantification of the risk of introgression is an important component of genetically modified crop regulation. Most theoretical introgression studies aimed at such quantification disregard one or more of the most important factors concerning introgression: realistic genetical mechanisms, rep...

Facial averageness and genetic quality: Testing heritability, genetic correlation with attractiveness, and the paternal age effect.

Science.gov (United States)

Lee, Anthony J; Mitchem, Dorian G; Wright, Margaret J; Martin, Nicholas G; Keller, Matthew C; Zietsch, Brendan P

2016-01-01

Popular theory suggests that facial averageness is preferred in a partner for genetic benefits to offspring. However, whether facial averageness is associated with genetic quality is yet to be established. Here, we computed an objective measure of facial averageness for a large sample ( N = 1,823) of identical and nonidentical twins and their siblings to test two predictions from the theory that facial averageness reflects genetic quality. First, we use biometrical modelling to estimate the heritability of facial averageness, which is necessary if it reflects genetic quality. We also test for a genetic association between facial averageness and facial attractiveness. Second, we assess whether paternal age at conception (a proxy of mutation load) is associated with facial averageness and facial attractiveness. Our findings are mixed with respect to our hypotheses. While we found that facial averageness does have a genetic component, and a significant phenotypic correlation exists between facial averageness and attractiveness, we did not find a genetic correlation between facial averageness and attractiveness (therefore, we cannot say that the genes that affect facial averageness also affect facial attractiveness) and paternal age at conception was not negatively associated with facial averageness. These findings support some of the previously untested assumptions of the 'genetic benefits' account of facial averageness, but cast doubt on others.

A review of multivariate analyses in imaging genetics

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Jingyu eLiu

2014-03-01

Full Text Available Recent advances in neuroimaging technology and molecular genetics provide the unique opportunity to investigate genetic influence on the variation of brain attributes. Since the year 2000, when the initial publication on brain imaging and genetics was released, imaging genetics has been a rapidly growing research approach with increasing publications every year. Several reviews have been offered to the research community focusing on various study designs. In addition to study design, analytic tools and their proper implementation are also critical to the success of a study. In this review, we survey recent publications using data from neuroimaging and genetics, focusing on methods capturing multivariate effects accommodating the large number of variables from both imaging data and genetic data. We group the analyses of genetic or genomic data into either a prior driven or data driven approach, including gene-set enrichment analysis, multifactor dimensionality reduction, principal component analysis, independent component analysis (ICA, and clustering. For the analyses of imaging data, ICA and extensions of ICA are the most widely used multivariate methods. Given detailed reviews of multivariate analyses of imaging data available elsewhere, we provide a brief summary here that includes a recently proposed method known as independent vector analysis. Finally, we review methods focused on bridging the imaging and genetic data by establishing multivariate and multiple genotype-phenotype associations, including sparse partial least squares, sparse canonical correlation analysis, sparse reduced rank regression and parallel ICA. These methods are designed to extract latent variables from both genetic and imaging data, which become new genotypes and phenotypes, and the links between the new genotype-phenotype pairs are maximized using different cost functions. The relationship between these methods along with their assumptions, advantages, and

Additional mechanisms conferring genetic susceptibility to Alzheimer's disease

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Miguel eCalero

2015-04-01

Full Text Available Familial Alzheimer's disease (AD, mostly associated with early onset, is caused by mutations in three genes (APP, PSEN1 and PSEN2 involved in the production of the amyloid  peptide. In contrast, the molecular mechanisms that trigger the most common late onset sporadic AD remain largely unknown. With the implementation of an increasing number of case-control studies and the upcoming of large-scale genome-wide association studies (GWAS there is a mounting list of genetic risk factors associated to common genetic variants that have been associated to sporadic AD. Besides APOE, that presents a strong association with the disease (OR~4, the rest of these genes have moderate or low degrees of association, with OR ranging from 0.88 to 1.23. Taking together, these genes may account only for a fraction of the attributable AD risk and therefore, rare variants and epistastic gene interactions should be taken into account in order to get the full picture of the genetic risks associated to AD. Here, we review recent whole-exome studies looking for rare variants, somatic brain mutations with a strong association to the disease, and several studies dealing with epistasis as additional mechanisms conferring genetic susceptibility to AD. Altogether, recent evidence underlines the importance of defining molecular and genetic pathways and networks rather than the contribution of specific genes.

Genetic variation in dieback resistance

DEFF Research Database (Denmark)

Lobo, Albin; Hansen, Jon Kehlet; McKinney, Lea Vig

2014-01-01

-eastern Zealand, Denmark, and confirmed the presence of substantial genetic variation in ash dieback susceptibility. The average crown damage increased in the trial from 61% in 2009 to 66% in 2012 and 72% in 2014, while the estimated heritability was 0.42 in both 2009 and 2012 but increased to 0.53 in 2014....... Genetic correlation between assessments was 0.88 between 2009 and 2012 and 0.91 between 2009 and 2014, suggesting fairly good possibilities for early selection of superior genotypes in the presence of high infection levels in the trial. The level of crown damage had strong negative effect on growth...

Global isolation by distance despite strong regional phylogeography in a small metazoan

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Mills Scott

2007-11-01

Full Text Available Abstract Background Small vagile eukaryotic organisms, which comprise a large proportion of the Earth's biodiversity, have traditionally been thought to lack the extent of population structuring and geographic speciation observed in larger taxa. Here we investigate the patterns of genetic diversity, amongst populations of the salt lake microscopic metazoan Brachionus plicatilis s. s. (sensu stricto (Rotifera: Monogononta on a global scale. We examine the phylogenetic relationships of geographic isolates from four continents using a 603 bp fragment of the mitochondrial COI gene to investigate patterns of phylogeographic subdivision in this species. In addition we investigate the relationship between genetic and geographic distances on a global scale to try and reconcile the paradox between the high vagility of this species and the previously reported patterns of restricted gene flow, even over local spatial scales. Results Analysis of global sequence diversity of B. plicatilis s. s. reveals the presence of four allopatric genetic lineages: North American-Far East Asian, Western Mediterranean, Australian, and an Eastern Mediterranean lineage represented by a single isolate. Geographically orientated substructure is also apparent within the three best sampled lineages. Surprisingly, given this strong phylogeographic structure, B. plicatilis s. s. shows a significant correlation between geographic and genetic distance on a global scale ('isolation by distance' – IBD. Conclusion Despite its cosmopolitan distribution and potential for high gene flow, B. plicatilis s. s. is strongly structured at a global scale. IBD patterns have traditionally been interpreted to indicate migration-drift equilibrium, although in this system equilibrium conditions are incompatible with the observed genetic structure. Instead, we suggest the pattern may have arisen through persistent founder effects, acting in a similar fashion to geographic barriers for larger

Global isolation by distance despite strong regional phylogeography in a small metazoan

Science.gov (United States)

Mills, Scott; Lunt, David H; Gómez, Africa

2007-01-01

Background Small vagile eukaryotic organisms, which comprise a large proportion of the Earth's biodiversity, have traditionally been thought to lack the extent of population structuring and geographic speciation observed in larger taxa. Here we investigate the patterns of genetic diversity, amongst populations of the salt lake microscopic metazoan Brachionus plicatilis s. s. (sensu stricto) (Rotifera: Monogononta) on a global scale. We examine the phylogenetic relationships of geographic isolates from four continents using a 603 bp fragment of the mitochondrial COI gene to investigate patterns of phylogeographic subdivision in this species. In addition we investigate the relationship between genetic and geographic distances on a global scale to try and reconcile the paradox between the high vagility of this species and the previously reported patterns of restricted gene flow, even over local spatial scales. Results Analysis of global sequence diversity of B. plicatilis s. s. reveals the presence of four allopatric genetic lineages: North American-Far East Asian, Western Mediterranean, Australian, and an Eastern Mediterranean lineage represented by a single isolate. Geographically orientated substructure is also apparent within the three best sampled lineages. Surprisingly, given this strong phylogeographic structure, B. plicatilis s. s. shows a significant correlation between geographic and genetic distance on a global scale ('isolation by distance' – IBD). Conclusion Despite its cosmopolitan distribution and potential for high gene flow, B. plicatilis s. s. is strongly structured at a global scale. IBD patterns have traditionally been interpreted to indicate migration-drift equilibrium, although in this system equilibrium conditions are incompatible with the observed genetic structure. Instead, we suggest the pattern may have arisen through persistent founder effects, acting in a similar fashion to geographic barriers for larger organisms. Our data indicates

A method to optimize the shield compact and lightweight combining the structure with components together by genetic algorithm and MCNP code.

Science.gov (United States)

Cai, Yao; Hu, Huasi; Pan, Ziheng; Hu, Guang; Zhang, Tao

2018-05-17

To optimize the shield for neutrons and gamma rays compact and lightweight, a method combining the structure and components together was established employing genetic algorithms and MCNP code. As a typical case, the fission energy spectrum of 235 U which mixed neutrons and gamma rays was adopted in this study. Six types of materials were presented and optimized by the method. Spherical geometry was adopted in the optimization after checking the geometry effect. Simulations have made to verify the reliability of the optimization method and the efficiency of the optimized materials. To compare the materials visually and conveniently, the volume and weight needed to build a shield are employed. The results showed that, the composite multilayer material has the best performance. Copyright © 2018 Elsevier Ltd. All rights reserved.

Adaptable component frameworks

DEFF Research Database (Denmark)

Katajainen, Jyrki; Simonsen, Bo

2009-01-01

The CPH STL is a special edition of the STL, the containers and algorithms part of the C++ standard library. The specification of the generic components of the STL is given in the C++ standard. Any implementation of the STL, e.g. the one that ships with your standard-compliant C++ compiler, should...... for vector, which is undoubtedly the most used container of the C++ standard library. In particular, we specify the details of a vector implementation that is safe with respect to referential integrity and strong exception safety. Additionally, we report the experiences and lessons learnt from...... the development of component frameworks which we hope to be of benefit to persons engaged in the design and implementation of generic software libraries....

Genetics of Unilateral and Bilateral Age-Related Macular Degeneration Severity Stages

NARCIS (Netherlands)

Schick, T.; Altay, L.; Viehweger, E.; Hoyng, C.B.; Hollander, A.I. den; Felsch, M.; Fauser, S.

2016-01-01

BACKGROUND: Age-related macular degeneration (AMD) is a common disease causing visual impairment and blindness. Various gene variants are strongly associated with late stage AMD, but little is known about the genetics of early forms of the disease. This study evaluated associations of genetic

Seagrass radiation after Messinian salinity crisis reflected by strong genetic structuring and out-of-Africa scenario (Ruppiaceae.

Directory of Open Access Journals (Sweden)

Ludwig Triest

Full Text Available Many aquatic plant and seagrass species are widespread and the origin of their continent-wide ranges might result from high gene flow levels. The response of species when extending northwards since the Last Glacial Maximum can be opposed to the structuring of their populations that survived glaciation cycles in southern regions. The peri-Mediterranean is a complex series of sea basins, coastlines, islands and river deltas with a unique history since the Messinian Crisis that potentially influenced allopatric processes of aquatic life. We tested whether vast ranges across Europe and the peri-Mediterranean of a global seagrass group (Ruppia species complexes can be explained by either overall high levels of gene flow or vicariance through linking population genetics, phylogeography and shallow phylogenetics. A multigene approach identified haplogroup lineages of two species complexes, of ancient and recent hybrids with most of the diversity residing in the South. High levels of connectivity over long distances were only observed at recently colonized northern ranges and in recently-filled seas following the last glaciation. A strong substructure in the southern Mediterranean explained an isolation-by-distance model across Europe. The oldest lineages of the southern Mediterranean Ruppia dated back to the period between the end of the Messinian and Late Pliocene. An imprint of ancient allopatric origin was left at basin level, including basal African lineages. Thus both vicariance in the South and high levels of connectivity in the North explained vast species ranges. Our findings highlight the need for interpreting global distributions of these seagrass and euryhaline species in the context of their origin and evolutionary significant units for setting up appropriate conservation strategies.

Genetic variation and trait correlations in a birdresistant pearl millet ...

African Journals Online (AJOL)

selection indices for effective improvement. There was significant genetic variation for grain yield and most yield component traits, indicating that selection within the population would be feasible. Genetic variation was, however not significant for the percent incidence of downy mildew, implying that selection for improving ...

Genetics of human body size and shape: pleiotropic and independent genetic determinants of adiposity.

Science.gov (United States)

Livshits, G; Yakovenko, K; Ginsburg, E; Kobyliansky, E

1998-01-01

The present study utilized pedigree data from three ethnically different populations of Kirghizstan, Turkmenia and Chuvasha. Principal component analysis was performed on a matrix of genetic correlations between 22 measures of adiposity, including skinfolds, circumferences and indices. Findings are summarized as follows: (1) All three genetic matrices were not positive definite and the first four factors retained even after exclusion RG > or = 1.0, explained from 88% to 97% of the total additive genetic variation in the 22 trials studied. This clearly emphasizes the massive involvement of pleiotropic gene effects in the variability of adiposity traits. (2) Despite the quite natural differences in pairwise correlations between the adiposity traits in the three ethnically different samples under study, factor analysis revealed a common basic pattern of covariability for the adiposity traits. In each of the three samples, four genetic factors were retained, namely, the amount of subcutaneous fat, the total body obesity, the pattern of distribution of subcutaneous fat and the central adiposity distribution. (3) Genetic correlations between the retained four factors were virtually non-existent, suggesting that several independent genetic sources may be governing the variation of adiposity traits. (4) Variance decomposition analysis on the obtained genetic factors leaves no doubt regarding the substantial familial and (most probably genetic) effects on variation of each factor in each studied population. The similarity of results in the three different samples indicates that the findings may be deemed valid and reliable descriptions of the genetic variation and covariation pattern of adiposity traits in the human species.

Variance components for body weight in Japanese quails (Coturnix japonica

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RO Resende

2005-03-01

Full Text Available The objective of this study was to estimate the variance components for body weight in Japanese quails by Bayesian procedures. The body weight at hatch (BWH and at 7 (BW07, 14 (BW14, 21 (BW21 and 28 days of age (BW28 of 3,520 quails was recorded from August 2001 to June 2002. A multiple-trait animal model with additive genetic, maternal environment and residual effects was implemented by Gibbs sampling methodology. A single Gibbs sampling with 80,000 rounds was generated by the program MTGSAM (Multiple Trait Gibbs Sampling in Animal Model. Normal and inverted Wishart distributions were used as prior distributions for the random effects and the variance components, respectively. Variance components were estimated based on the 500 samples that were left after elimination of 30,000 rounds in the burn-in period and 100 rounds of each thinning interval. The posterior means of additive genetic variance components were 0.15; 4.18; 14.62; 27.18 and 32.68; the posterior means of maternal environment variance components were 0.23; 1.29; 2.76; 4.12 and 5.16; and the posterior means of residual variance components were 0.084; 6.43; 22.66; 31.21 and 30.85, at hatch, 7, 14, 21 and 28 days old, respectively. The posterior means of heritability were 0.33; 0.35; 0.36; 0.43 and 0.47 at hatch, 7, 14, 21 and 28 days old, respectively. These results indicate that heritability increased with age. On the other hand, after hatch there was a marked reduction in the maternal environment variance proportion of the phenotypic variance, whose estimates were 0.50; 0.11; 0.07; 0.07 and 0.08 for BWH, BW07, BW14, BW21 and BW28, respectively. The genetic correlation between weights at different ages was high, except for those estimates between BWH and weight at other ages. Changes in body weight of quails can be efficiently achieved by selection.

Viva la Familia Study: genetic and environmental contributions to childhood obesity and its comorbidities in the Hispanic population.

Science.gov (United States)

Butte, Nancy F; Cai, Guowen; Cole, Shelley A; Comuzzie, Anthony G

2006-09-01

Genetic and environmental contributions to childhood obesity are poorly delineated. The Viva la Familia Study was designed to genetically map childhood obesity and its comorbidities in the Hispanic population. The objectives of this report were to describe the study design and to summarize genetic and environmental contributions to the phenotypic variation in obesity and risk factors for metabolic diseases in Hispanic children. The Viva la Familia cohort consisted of 1030 children from 319 families selected based on an overweight proband between the ages of 4 and 19 y. In-depth phenotyping to characterize the overweight children and their siblings included anthropometric and body-composition traits by dual-energy X-ray absorptiometry and assessments of diet by 24-h recalls, physical activity by accelerometry, and risk factors for metabolic diseases by standard biochemical methods. Univariate quantitative genetic analysis was used to partition phenotypic variance into additive genetic and environmental components by using the computer program SOLAR. Sex, age, and environmental covariates explained 1-91% of the phenotypic variance. Heritabilities of anthropometric indexes ranged from 0.24 to 0.75. Heritability coefficients for the body-composition traits ranged from 0.18 to 0.35. Diet and physical activity presented heritabilities of 0.32 to 0.69. Risk factors for metabolic diseases were heritable with coefficients ranging from 0.25 to 0.73. Significant genetic correlations between obesity traits and risk factors for metabolic diseases substantiated pleiotropy between traits. The Viva la Familia Study provides evidence of a strong genetic contribution to the high prevalence of obesity and its comorbidities in Hispanic children.

Octodon Degus: A Strong Attractor for Alzheimer Research

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Rafael Castro-Fuentes

2013-01-01

Full Text Available   The most popular animal models of Alzheimer’s disease (AD are transgenic mice expressing human genes with known mutations which do not represent the most abundant sporadic form of the disease. An increasing number of genetic, vascular and psychosocial data strongly support that the Octodon degus, a moderate-sized and diurnal precocial rodent, provides a naturalistic model for the study of the early neurodegenerative process associated with sporadic AD. In this minireview we describe and analyze the risk factors that contribute to Alzheimer-like characteristics in the degus, following recent publications, and establish some guidelines for future studies in this model of natural aging associated with the disease. Given the heterogeneity of current data derived from the diverse transgenic animal models of AD, now may be the time for the degus to become a strong attractor for academic research labs and companies involved with AD. This may help to understand the mechanisms responsible for the early neurodegenerative process associated with this devastating disease.

Octodon Degus: A Strong Attractor for Alzheimer Research

Directory of Open Access Journals (Sweden)

Rafael Castro-Fuentes

2013-02-01

Full Text Available The most popular animal models of Alzheimer’s disease (AD are transgenic mice expressing human genes with known mutations which do not represent the most abundant sporadic form of the disease. An increasing number of genetic, vascular and psychosocial data strongly support that the Octodon degus, a moderate-sized and diurnal precocial rodent, provides a naturalistic model for the study of the early neurodegenerative process associated with sporadic AD. In this minireview we describe and analyze the risk factors that contribute to Alzheimer-like characteristics in the degus, following recent publications, and establish some guidelines for future studies in this model of natural aging associated with the disease. Given the heterogeneity of current data derived from the diverse transgenic animal models of AD, now may be the time for the degus to become a strong attractor for academic research labs and companies involved with AD. This may help to understand the mechanisms responsible for the early neurodegenerative process associated with this devastating disease.

Genetic variation facilitates seedling establishment but not population growth rate of a perennial invader.

Science.gov (United States)

Li, Shou-Li; Vasemägi, Anti; Ramula, Satu

2016-01-01

Assessing the demographic consequences of genetic variation is fundamental to invasion biology. However, genetic and demographic approaches are rarely combined to explore the effects of genetic variation on invasive populations in natural environments. This study combined population genetics, demographic data and a greenhouse experiment to investigate the consequences of genetic variation for the population fitness of the perennial, invasive herb Lupinus polyphyllus. Genetic and demographic data were collected from 37 L. polyphyllus populations representing different latitudes in Finland, and genetic variation was characterized based on 13 microsatellite loci. Associations between genetic variation and population size, population density, latitude and habitat were investigated. Genetic variation was then explored in relation to four fitness components (establishment, survival, growth, fecundity) measured at the population level, and the long-term population growth rate (λ). For a subset of populations genetic variation was also examined in relation to the temporal variability of λ. A further assessment was made of the role of natural selection in the observed variation of certain fitness components among populations under greenhouse conditions. It was found that genetic variation correlated positively with population size, particularly at higher latitudes, and differed among habitat types. Average seedling establishment per population increased with genetic variation in the field, but not under greenhouse conditions. Quantitative genetic divergence (Q(ST)) based on seedling establishment in the greenhouse was smaller than allelic genetic divergence (F'(ST)), indicating that unifying selection has a prominent role in this fitness component. Genetic variation was not associated with average survival, growth or fecundity measured at the population level, λ or its variability. The study suggests that although genetic variation may facilitate plant invasions by

The Tourette International Collaborative Genetics (TIC Genetics) study, finding the genes causing Tourette syndrome : objectives and methods

NARCIS (Netherlands)

Dietrich, Andrea; Fernandez, Thomas V.; King, Robert A.; State, Matthew W.; Tischfield, Jay A.; Hoekstra, Pieter J.; Heiman, Gary A.

Tourette syndrome (TS) is a neuropsychiatric disorder characterized by recurrent motor and vocal tics, often accompanied by obsessive-compulsive disorder and/or attention-deficit/hyperactivity disorder. While the evidence for a genetic contribution is strong, its exact nature has yet to be clarified

Why Are High Altitude Natives So Strong at High Altitude? Nature vs. Nurture: Genetic Factors vs. Growth and Development.

Science.gov (United States)

Brutsaert, Tom

Among high-altitude natives there is evidence of a general hypoxia tolerance leading to enhanced performance and/or increased capacity in several important domains. These domains likely include an enhanced physical work capacity, an enhanced reproductive capacity, and an ability to resist several common pathologies of chronic high-altitude exposure. The "strength" of the high-altitude native in this regard may have both a developmental and a genetic basis, although there is better evidence for the former (developmental effects) than for the latter. For example, early-life hypoxia exposure clearly results in lung growth and remodeling leading to an increased O2 diffusing capacity in adulthood. Genetic research has yet to reveal a population genetic basis for enhanced capacity in high-altitude natives, but several traits are clearly under genetic control in Andean and Tibetan populations e.g., resting and exercise arterial O2 saturation (SaO2). This chapter reviews the effects of nature and nurture on traits that are relevant to the process of gas exchange, including pulmonary volumes and diffusion capacity, the maximal oxygen consumption (VO2max), the SaO2, and the alveolar-arterial oxygen partial pressure difference (A-aDO2) during exercise.

Fragmentation reduces regional-scale spatial genetic structure in a wind-pollinated tree because genetic barriers are removed.

Science.gov (United States)

Wang, Rong; Compton, Stephen G; Shi, Yi-Su; Chen, Xiao-Yong

2012-09-01

Gene flow strongly influences the regional genetic structuring of plant populations. Seed and pollen dispersal patterns can respond differently to the increased isolation resulting from habitat fragmentation, with unpredictable consequences for gene flow and population structuring. In a recently fragmented landscape we compared the pre- and post-fragmentation genetic structure of populations of a tree species where pollen and seed dispersal respond differentially to forest fragmentation generated by flooding. Castanopsis sclerophylla is wind-pollinated, with seeds that are dispersed by gravity and rodents. Using microsatellites, we found no significant difference in genetic diversity between pre- and post-fragmentation cohorts. Significant genetic structure was observed in pre-fragmentation cohorts, due to an unknown genetic barrier that had isolated one small population. Among post-fragmentation cohorts this genetic barrier had disappeared and genetic structure was significantly weakened. The strengths of genetic structuring were at a similar level in both cohorts, suggesting that overall gene flow of C. sclerophylla has been unchanged by fragmentation at the regional scale. Fragmentation has blocked seed dispersal among habitats, but this appears to have been compensated for by enhanced pollen dispersal, as indicated by the disappearance of a genetic barrier, probably as a result of increased wind speeds and easier pollen movement over water. Extensive pollen flow can counteract some negative effects of fragmentation and assist the long-term persistence of small remnant populations.

Role of Genomic Typing in Taxonomy, Evolutionary Genetics, and Microbial Epidemiology

OpenAIRE

van Belkum, Alex; Struelens, Marc; de Visser, Arjan; Verbrugh, Henri; Tibayrenc, Michel

2001-01-01

Currently, genetic typing of microorganisms is widely used in several major fields of microbiological research. Taxonomy, research aimed at elucidation of evolutionary dynamics or phylogenetic relationships, population genetics of microorganisms, and microbial epidemiology all rely on genetic typing data for discrimination between genotypes. Apart from being an essential component of these fundamental sciences, microbial typing clearly affects several areas of applied microbiogical research. ...

Role of genomic typing in taxonomy, evolutionary genetics, and microbial epidemiology.

OpenAIRE

Belkum, Alex; Struelens, M.; Visser, Arjan; Verbrugh, Henri; Tibayrench, M.

2001-01-01

textabstractCurrently, genetic typing of microorganisms is widely used in several major fields of microbiological research. Taxonomy, research aimed at elucidation of evolutionary dynamics or phylogenetic relationships, population genetics of microorganisms, and microbial epidemiology all rely on genetic typing data for discrimination between genotypes. Apart from being an essential component of these fundamental sciences, microbial typing clearly affects several areas of applied microbiologi...

The search for putative unifying genetic factors for components of the metabolic syndrome

DEFF Research Database (Denmark)

Sjögren, M; Lyssenko, V; Jonsson, Anna Elisabet

2008-01-01

The metabolic syndrome is a cluster of factors contributing to increased risk of cardiovascular disease and type 2 diabetes but unifying mechanisms have not been identified. Our aim was to study whether common variations in 17 genes previously associated with type 2 diabetes or components...... of the metabolic syndrome and variants in nine genes with inconsistent association with at least two components of the metabolic syndrome would also predict future development of components of the metabolic syndrome, individually or in combination....

Correlation of horizontal and vertical components of strong ground motion for response-history analysis of safety-related nuclear facilities

Energy Technology Data Exchange (ETDEWEB)

Huang, Yin-Nan, E-mail: ynhuang@ntu.edu.tw [Dept. of Civil Engineering, National Taiwan University, No. 1, Sec. 4, Roosevelt Rd., Taipei 10617, Taiwan (China); Yen, Wen-Yi, E-mail: b01501059@ntu.edu.tw [Dept. of Civil Engineering, National Taiwan University, No. 1, Sec. 4, Roosevelt Rd., Taipei 10617, Taiwan (China); Whittaker, Andrew S., E-mail: awhittak@buffalo.edu [Dept. of Civil, Structural and Environmental Engineering, MCEER, State University of New York at Buffalo, Buffalo, NY 14260 (United States)

2016-12-15

Highlights: • The correlation of components of ground motion is studied using 1689 sets of records. • The data support an upper bound of 0.3 on the correlation coefficient. • The data support the related requirement in the upcoming edition of ASCE Standard 4. - Abstract: Design standards for safety-related nuclear facilities such as ASCE Standard 4-98 and ASCE Standard 43-05 require the correlation coefficient for two orthogonal components of ground motions for response-history analysis to be less than 0.3. The technical basis of this requirement was developed by Hadjian three decades ago using 50 pairs of recorded ground motions that were available at that time. In this study, correlation coefficients for (1) two horizontal components, and (2) the vertical component and one horizontal component, of a set of ground motions are computed using records from a ground-motion database compiled recently for large-magnitude shallow crustal earthquakes. The impact of the orientation of the orthogonal horizontal components on the correlation coefficient of ground motions is discussed. The rules in the forthcoming edition of ASCE Standard 4 for the correlation of components in a set of ground motions are shown to be reasonable.

Genetic diversity among 16 genotypes of Coffea arabica in the Brazilian cerrado.

Science.gov (United States)

Machado, C M S; Pimentel, N S; Golynsk, A; Ferreira, A; Vieira, H D; Partelli, F L

2017-09-21

For the selection of coffee plants that have favorable characteristics, it is necessary to evaluate variables related to production. Knowledge of the genetic divergence of arabica coffee is of extreme importance, as this knowledge can be associated with plant breeding programs in order to combine genetic divergence with good productive performance. The objective of this study was to evaluate the genetic divergence among 16 genotypes of Coffea arabica with the purpose of identifying the most dissimilar genotypes for the establishment of breeding programs and adaptation to the Brazilian cerrado. The genetic divergence was evaluated using multivariate procedures, the analysis of the average grouping unweighted pair group method with arithmetic mean (UPGMA) and main components in 2013 and 2014. Eight characters were evaluated in an experiment conducted in Morrinhos, Goiás. The presence of genetic divergence among the 16 C. arabica genotypes under cerrado conditions was recorded. The formation of UPGMA groups for the evaluated characteristics was pertinent due to the number of genotypes. The first three major components accounted for 81.77% of the total variance. The genotype H-419-3-4-4-13(C-241) of low size was the most divergent, followed by Catucaí 2 SL and Catiguá MG2, according to the main components.

Comparing estimates of genetic variance across different relationship models.

Science.gov (United States)

Legarra, Andres

2016-02-01

Use of relationships between individuals to estimate genetic variances and heritabilities via mixed models is standard practice in human, plant and livestock genetics. Different models or information for relationships may give different estimates of genetic variances. However, comparing these estimates across different relationship models is not straightforward as the implied base populations differ between relationship models. In this work, I present a method to compare estimates of variance components across different relationship models. I suggest referring genetic variances obtained using different relationship models to the same reference population, usually a set of individuals in the population. Expected genetic variance of this population is the estimated variance component from the mixed model times a statistic, Dk, which is the average self-relationship minus the average (self- and across-) relationship. For most typical models of relationships, Dk is close to 1. However, this is not true for very deep pedigrees, for identity-by-state relationships, or for non-parametric kernels, which tend to overestimate the genetic variance and the heritability. Using mice data, I show that heritabilities from identity-by-state and kernel-based relationships are overestimated. Weighting these estimates by Dk scales them to a base comparable to genomic or pedigree relationships, avoiding wrong comparisons, for instance, "missing heritabilities". Copyright © 2015 Elsevier Inc. All rights reserved.

Variants of SCARB1 and VDR Involved in Complex Genetic Interactions May Be Implicated in the Genetic Susceptibility to Clear Cell Renal Cell Carcinoma

Directory of Open Access Journals (Sweden)

Ewelina Pośpiech

2015-01-01

Full Text Available The current data are still inconclusive in terms of a genetic component involved in the susceptibility to renal cell carcinoma. Our aim was to evaluate 40 selected candidate polymorphisms for potential association with clear cell renal cell carcinoma (ccRCC based on independent group of 167 patients and 200 healthy controls. The obtained data were searched for independent effects of particular polymorphisms as well as haplotypes and genetic interactions. Association testing implied position rs4765623 in the SCARB1 gene (OR=1.688, 95% CI: 1.104–2.582, P=0.016 and a haplotype in VDR comprising positions rs739837, rs731236, rs7975232, and rs1544410 (P=0.012 to be the risk factors in the studied population. The study detected several epistatic effects contributing to the genetic susceptibility to ccRCC. Variation in GNAS1 was implicated in a strong synergistic interaction with BIRC5. This effect was part of a model suggested by multifactor dimensionality reduction method including also a synergy between GNAS1 and SCARB1 (P=0.036. Significance of GNAS1-SCARB1 interaction was further confirmed by logistic regression (P=0.041, which also indicated involvement of SCARB1 in additional interaction with EPAS1 (P=0.008 as well as revealing interactions between GNAS1 and EPAS1 (P=0.016, GNAS1 and MC1R (P=0.031, GNAS1 and VDR (P=0.032, and MC1R and VDR (P=0.035.

The devil is in the details: genetic variation in introduced populations and its contributions to invasion.

Science.gov (United States)

Dlugosch, Katrina M; Anderson, Samantha R; Braasch, Joseph; Cang, F Alice; Gillette, Heather D

2015-05-01

The influence of genetic variation on invasion success has captivated researchers since the start of the field of invasion genetics 50 years ago. We review the history of work on this question and conclude that genetic variation-as surveyed with molecular markers-appears to shape invasion rarely. Instead, there is a significant disconnect between marker assays and ecologically relevant genetic variation in introductions. We argue that the potential for adaptation to facilitate invasion will be shaped by the details of genotypes affecting phenotypes, and we highlight three areas in which we see opportunities to make powerful new insights. (i) The genetic architecture of adaptive variation. Traits shaped by large-effect alleles may be strongly impacted by founder events yet more likely to respond to selection when genetic drift is strong. Large-effect loci may be especially relevant for traits involved in biotic interactions. (ii) Cryptic genetic variation exposed during invasion. Introductions have strong potential to uncover masked variation due to alterations in genetic and ecological environments. (iii) Genetic interactions during admixture of multiple source populations. As divergence among sources increases, positive followed by increasingly negative effects of admixture should be expected. Although generally hypothesized to be beneficial during invasion, admixture is most often reported among sources of intermediate divergence, supporting the possibility that incompatibilities among divergent source populations might be limiting their introgression. Finally, we note that these details of invasion genetics can be coupled with comparative demographic analyses to link genetic changes to the evolution of invasiveness itself. © 2015 John Wiley & Sons Ltd.

Strong seismic ground motion propagation

International Nuclear Information System (INIS)

Seale, S.; Archuleta, R.; Pecker, A.; Bouchon, M.; Mohammadioun, G.; Murphy, A.; Mohammadioun, B.

1988-10-01

At the McGee Creek, California, site, 3-component strong-motion accelerometers are located at depths of 166 m, 35 m and 0 m. The surface material is glacial moraine, to a depth of 30.5 m, overlying homfels. Accelerations were recorded from two California earthquakes: Round Valley, M L 5.8, November 23, 1984, 18:08 UTC and Chalfant Valley, M L 6.4, July 21, 1986, 14:42 UTC. By separating out the SH components of acceleration, we were able to determine the orientations of the downhole instruments. By separating out the SV component of acceleration, we were able to determine the approximate angle of incidence of the signal at 166 m. A constant phase velocity Haskell-Thomson model was applied to generate synthetic SH seismograms at the surface using the accelerations recorded at 166 m. In the frequency band 0.0 - 10.0 Hz, we compared the filtered synthetic records to the filtered surface data. The onset of the SH pulse is clearly seen, as are the reflections from the interface at 30.5 m. The synthetic record closely matches the data in amplitude and phase. The fit between the synthetic accelerogram and the data shows that the seismic amplification at the surface is a result of the contrast of the impedances (shear stiffnesses) of the near surface materials

Males and females contribute unequally to offspring genetic diversity in the polygynandrous mating system of wild boar.

Directory of Open Access Journals (Sweden)

Javier Pérez-González

Full Text Available The maintenance of genetic diversity across generations depends on both the number of reproducing males and females. Variance in reproductive success, multiple paternity and litter size can all affect the relative contributions of male and female parents to genetic variation of progeny. The mating system of the wild boar (Sus scrofa has been described as polygynous, although evidence of multiple paternity in litters has been found. Using 14 microsatellite markers, we evaluated the contribution of males and females to genetic variation in the next generation in independent wild boar populations from the Iberian Peninsula and Hungary. Genetic contributions of males and females were obtained by distinguishing the paternal and maternal genetic component inherited by the progeny. We found that the paternally inherited genetic component of progeny was more diverse than the maternally inherited component. Simulations showed that this finding might be due to a sampling bias. However, after controlling for the bias by fitting both the genetic diversity in the adult population and the number of reproductive individuals in the models, paternally inherited genotypes remained more diverse than those inherited maternally. Our results suggest new insights into how promiscuous mating systems can help maintain genetic variation.

Genetics and epigenetics of autism: A Review.

Science.gov (United States)

Waye, Mary M Y; Cheng, Ho Yu

2018-04-01

Autism is a developmental disorder that starts before age 3 years, and children with autism have impairment in both social interaction and communication, and have restricted, repetitive, and stereotyped patterns of behavior, interests, and activities. There is a strong heritable component of autism and autism spectrum disorder (ASD) as studies have shown that parents who have a child with ASD have a 2-18% chance of having a second child with ASD. The prevalence of autism and ASD have been increasing during the last 3 decades and much research has been carried out to understand the etiology, so as to develop novel preventive and treatment strategies. This review aims at summarizing the latest research studies related to autism and ASD, focusing not only on the genetics but also some epigenetic findings of autism/ASD. Some promising areas of research using transgenic/knockout animals and some ideas related to potential novel treatment and prevention strategies will be discussed. © 2017 The Chinese University of Hong Kong. Psychiatry and Clinical Neurosciences © 2017 Japanese Society of Psychiatry and Neurology.

Genetic and Psychosocial Predictors of Aggression: Variable Selection and Model Building With Component-Wise Gradient Boosting

Directory of Open Access Journals (Sweden)

Robert Suchting

2018-05-01

Full Text Available Rationale: Given datasets with a large or diverse set of predictors of aggression, machine learning (ML provides efficient tools for identifying the most salient variables and building a parsimonious statistical model. ML techniques permit efficient exploration of data, have not been widely used in aggression research, and may have utility for those seeking prediction of aggressive behavior.Objectives: The present study examined predictors of aggression and constructed an optimized model using ML techniques. Predictors were derived from a dataset that included demographic, psychometric and genetic predictors, specifically FK506 binding protein 5 (FKBP5 polymorphisms, which have been shown to alter response to threatening stimuli, but have not been tested as predictors of aggressive behavior in adults.Methods: The data analysis approach utilized component-wise gradient boosting and model reduction via backward elimination to: (a select variables from an initial set of 20 to build a model of trait aggression; and then (b reduce that model to maximize parsimony and generalizability.Results: From a dataset of N = 47 participants, component-wise gradient boosting selected 8 of 20 possible predictors to model Buss-Perry Aggression Questionnaire (BPAQ total score, with R2 = 0.66. This model was simplified using backward elimination, retaining six predictors: smoking status, psychopathy (interpersonal manipulation and callous affect, childhood trauma (physical abuse and neglect, and the FKBP5_13 gene (rs1360780. The six-factor model approximated the initial eight-factor model at 99.4% of R2.Conclusions: Using an inductive data science approach, the gradient boosting model identified predictors consistent with previous experimental work in aggression; specifically psychopathy and trauma exposure. Additionally, allelic variants in FKBP5 were identified for the first time, but the relatively small sample size limits generality of results and calls for

Disentangling hexaploid genetics : towards DNA-informed breeding for postharvest performance in chrysanthemum

NARCIS (Netherlands)

Geest, van Geert

2017-01-01

DNA-informed selection can strongly improve the process of plant breeding. It requires the detection of DNA polymorphisms, calculation of genetic linkage, access to reliable phenotypes and methods to detect genetic loci associated with phenotypic traits of interest. Cultivated chrysanthemum is an

How does farmer connectivity influence livestock genetic structure?

DEFF Research Database (Denmark)

Berthouly, C; Do, Duy Ngoc; Thévenon, S

2009-01-01

Assessing how genes flow across populations is a key component of conservation genetics. Gene flow in a natural population depends on ecological traits and the local environment, whereas for a livestock population, gene flow is driven by human activities. Spatial organization, relationships between...... farmers and their husbandry practices will define the farmer's network and so determine farmer connectivity. It is thus assumed that farmer connectivity will affect the genetic structure of their livestock. To test this hypothesis, goats reared by four different ethnic groups in a Vietnamese province were......, ethnicity and husbandry practices. In this study, we clearly linked the livestock genetic pattern to farmer connectivity and showed the importance of taking into account spatial information in genetic studies....

Genetic population structure of the desert shrub species lycium ruthenicum inferred from chloroplast dna

International Nuclear Information System (INIS)

Chen, H.; Yonezawa, T.

2014-01-01

Lycium ruthenicum (Solananeae), a spiny shrub mostly distributed in the desert regions of north and northwest China, has been shown to exhibit high tolerance to the extreme environment. In this study, the phylogeography and evolutionary history of L. ruthenicum were examined, on the basis of 80 individuals from eight populations. Using the sequence variations of two spacer regions of chloroplast DNA (trnH-psbA and rps16-trnK) , the absence of a geographic component in the chloroplast DNA genetic structure was identified (GST = 0.351, NST = 0.304, NST< GST), which was consisted with the result of SAMOVA, suggesting weak phylogeographic structure of this species. Phylogenetic and network analyses showed that a total of 10 haplotypes identified in the present study clustered into two clades, in which clade I harbored the ancestral haplotypes that inferred two independent glacial refugia in the middle of Qaidam Basin and the western Inner Mongolia. The existence of regional evolutionary differences was supported by GENETREE, which revealed that one of the population in Qaidam Basin and the two populations in Tarim Basin had experienced rapid expansion, and the other populations retained relatively stable population size during the Pleistocene . Given the results of long-term gene flow and pairwise differences, strong gene flow was insufficient to reduce the genetic differentiation among populations or within populations, probably due to the genetic composition containing a common haplotype and the high number of private haplotypes fixed for most of the population. The divergence times of different lineages were consistent with the rapid uplift phases of the Qinghai-Tibetan Plateau and the initiation and expansion of deserts in northern China, suggesting that the origin and evolution of L. ruthenicum were strongly influenced by Quaternary environment changes. (author)

Genetic transformation of fruit trees: current status and remaining challenges.

Science.gov (United States)

Gambino, Giorgio; Gribaudo, Ivana

2012-12-01

Genetic transformation has emerged as a powerful tool for genetic improvement of fruit trees hindered by their reproductive biology and their high levels of heterozygosity. For years, genetic engineering of fruit trees has focussed principally on enhancing disease resistance (against viruses, fungi, and bacteria), although there are few examples of field cultivation and commercial application of these transgenic plants. In addition, over the years much work has been performed to enhance abiotic stress tolerance, to induce modifications of plant growth and habit, to produce marker-free transgenic plants and to improve fruit quality by modification of genes that are crucially important in the production of specific plant components. Recently, with the release of several genome sequences, studies of functional genomics are becoming increasingly important: by modification (overexpression or silencing) of genes involved in the production of specific plant components is possible to uncover regulatory mechanisms associated with the biosynthesis and catabolism of metabolites in plants. This review focuses on the main advances, in recent years, in genetic transformation of the most important species of fruit trees, devoting particular attention to functional genomics approaches and possible future challenges of genetic engineering for these species in the post-genomic era.

Qubit absorption refrigerator at strong coupling

Science.gov (United States)

Mu, Anqi; Agarwalla, Bijay Kumar; Schaller, Gernot; Segal, Dvira

2017-12-01

We demonstrate that a quantum absorption refrigerator (QAR) can be realized from the smallest quantum system, a qubit, by coupling it in a non-additive (strong) manner to three heat baths. This function is un-attainable for the qubit model under the weak system-bath coupling limit, when the dissipation is additive. In an optimal design, the reservoirs are engineered and characterized by a single frequency component. We then obtain closed expressions for the cooling window and refrigeration efficiency, as well as bounds for the maximal cooling efficiency and the efficiency at maximal power. Our results agree with macroscopic designs and with three-level models for QARs, which are based on the weak system-bath coupling assumption. Beyond the optimal limit, we show with analytical calculations and numerical simulations that the cooling efficiency varies in a non-universal manner with model parameters. Our work demonstrates that strongly-coupled quantum machines can exhibit function that is un-attainable under the weak system-bath coupling assumption.

GENETIC ENGINEERING OF ENHANCED MICROBIAL NITRIFICATION

Science.gov (United States)

Experiments were conducted to introduce genetic information in the form of antibiotic or mercuric ion resistance genes into Nitrobacter hamburgensis strain X14. The resistance genes were either stable components of broad host range plasmids or transposable genes on methods for p...

Novel genetic tools for Hansenula polymorpha

NARCIS (Netherlands)

Saraya, Ruchi; Krikken, Arjen M; Kiel, Jan A K W; Baerends, Richard J S; Veenhuis, Marten; van der Klei, Ida J

Hansenula polymorpha is an important yeast in industrial biotechnology. In addition, it is extensively used in fundamental research devoted to unravel the principles of peroxisome biology and nitrate assimilation. Here we present an overview of key components of the genetic toolbox for H.

The Geographic Distribution of Saccharomyces cerevisiae Isolates within three Italian Neighboring Winemaking Regions Reveals Strong Differences in Yeast Abundance, Genetic Diversity and Industrial Strain Dissemination

Directory of Open Access Journals (Sweden)

Alessia Viel

2017-08-01

Full Text Available In recent years the interest for natural fermentations has been re-evaluated in terms of increasing the wine terroir and managing more sustainable winemaking practices. Therefore, the level of yeast genetic variability and the abundance of Saccharomyces cerevisiae native populations in vineyard are becoming more and more crucial at both ecological and technological level. Among the factors that can influence the strain diversity, the commercial starter release that accidentally occur in the environment around the winery, has to be considered. In this study we led a wide scale investigation of S. cerevisiae genetic diversity and population structure in the vineyards of three neighboring winemaking regions of Protected Appellation of Origin, in North-East of Italy. Combining mtDNA RFLP and microsatellite markers analyses we evaluated 634 grape samples collected over 3 years. We could detect major differences in the presence of S. cerevisiae yeasts, according to the winemaking region. The population structures revealed specificities of yeast microbiota at vineyard scale, with a relative Appellation of Origin area homogeneity, and transition zones suggesting a geographic differentiation. Surprisingly, we found a widespread industrial yeast dissemination that was very high in the areas where the native yeast abundance was low. Although geographical distance is a key element involved in strain distribution, the high presence of industrial strains in vineyard reduced the differences between populations. This finding indicates that industrial yeast diffusion it is a real emergency and their presence strongly interferes with the natural yeast microbiota.

Recent genetic discoveries in osteoporosis, sarcopenia and obesity.

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Urano, Tomohiko; Inoue, Satoshi

2015-01-01

Osteoporosis is a skeletal disorder characterized by low bone mineral density (BMD) and an increased susceptibility to fractures. Evidence from genetic studies indicates that BMD, a complex quantitative trait with a normal distribution, is genetically controlled. Genome-wide association studies (GWAS) as well as studies using candidate gene approaches have identified single-nucleotide polymorphisms (SNPs) that are associated with BMD, osteoporosis and osteoporotic fractures. These SNPs have been mapped close to or within genes including those encoding WNT/β-catenin signaling proteins. Understanding the genetics of osteoporosis will help to identify novel candidates for diagnostic and therapeutic targets. Genetic factors are also important for the development of sarcopenia, which is characterized by a loss of lean body mass, and obesity, which is characterized by high fat mass. Hence, in this review, we discuss the genetic factors, identified by genetic studies, which regulate the body components related to osteoporosis, sarcopenia, and obesity.

Genetic influences on alcohol use behaviors have diverging developmental trajectories: a prospective study among male and female twins.

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Meyers, Jacquelyn L; Salvatore, Jessica E; Vuoksimaa, Eero; Korhonen, Tellervo; Pulkkinen, Lea; Rose, Richard J; Kaprio, Jaakko; Dick, Danielle M

2014-11-01

Both alcohol-specific genetic factors and genetic factors related to externalizing behavior influence problematic alcohol use. Little is known, however, about the etiologic role of these 2 components of genetic risk on alcohol-related behaviors across development. Prior studies conducted in a male cohort of twins suggest that externalizing genetic factors are important for predicting heavy alcohol use in adolescence, whereas alcohol-specific genetic factors increase in importance during the transition to adulthood. In this report, we studied twin brothers and sisters and brother-sister twin pairs to examine such developmental trajectories and investigate whether sex and cotwin sex effects modify these genetic influences. We used prospective, longitudinal twin data collected between ages 12 and 22 within the population-based FinnTwin12 cohort study (analytic n = 1,864). Our dependent measures of alcohol use behaviors included alcohol initiation (age 12), intoxication frequency (ages 14 and 17), and alcohol dependence criteria (age 22). Each individual's genetic risk of alcohol use disorders (AUD-GR) was indexed by his/her parents' and cotwin's DSM-IV Alcohol Dependence (AD) criterion counts. Likewise, each individual's genetic risk of externalizing disorders (EXT-GR) was indexed with a composite measure of parents' and cotwin's DSM-IV Conduct Disorder and Antisocial Personality Disorder criterion counts. EXT-GR was most strongly related to alcohol use behaviors during adolescence, while AUD-GR was most strongly related to alcohol problems in young adulthood. Further, sex of the twin and sex of the cotwin significantly moderated the associations between genetic risk and alcohol use behaviors across development: AUD-GR influenced early adolescent alcohol use behaviors in females more than in males, and EXT-GR influenced age 22 AD more in males than in females. In addition, the associations of AUD-GR and EXT-GR with intoxication frequency were greater among 14- and

Applying genetic algorithms for calibrating a hexagonal cellular automata model for the simulation of debris flows characterised by strong inertial effects

Science.gov (United States)

Iovine, G.; D'Ambrosio, D.; Di Gregorio, S.

2005-03-01

In modelling complex a-centric phenomena which evolve through local interactions within a discrete time-space, cellular automata (CA) represent a valid alternative to standard solution methods based on differential equations. Flow-type phenomena (such as lava flows, pyroclastic flows, earth flows, and debris flows) can be viewed as a-centric dynamical systems, and they can therefore be properly investigated in CA terms. SCIDDICA S 4a is the last release of a two-dimensional hexagonal CA model for simulating debris flows characterised by strong inertial effects. S 4a has been obtained by progressively enriching an initial simplified model, originally derived for simulating very simple cases of slow-moving flow-type landslides. Using an empirical strategy, in S 4a, the inertial character of the flowing mass is translated into CA terms by means of local rules. In particular, in the transition function of the model, the distribution of landslide debris among the cells is obtained through a double cycle of computation. In the first phase, the inertial character of the landslide debris is taken into account by considering indicators of momentum. In the second phase, any remaining debris in the central cell is distributed among the adjacent cells, according to the principle of maximum possible equilibrium. The complexities of the model and of the phenomena to be simulated suggested the need for an automated technique of evaluation for the determination of the best set of global parameters. Accordingly, the model is calibrated using a genetic algorithm and by considering the May 1998 Curti-Sarno (Southern Italy) debris flow. The boundaries of the area affected by the debris flow are simulated well with the model. Errors computed by comparing the simulations with the mapped areal extent of the actual landslide are smaller than those previously obtained without genetic algorithms. As the experiments have been realised in a sequential computing environment, they could be

Spatio temporal media components for neurofeedback

DEFF Research Database (Denmark)

Jensen, Camilla Birgitte Falk; Petersen, Michael Kai; Larsen, Jakob Eg

2013-01-01

A class of Brain Computer Interfaces (BCI) involves interfaces for neurofeedback training, where a user can learn to self-regulate brain activity based on real-time feedback. These particular interfaces are constructed from audio-visual components and temporal settings, which appear to have...... a strong influence on the ability to control brain activity. Therefore, identifying the different interface components and exploring their individual effects might be key for constructing new interfaces that support more efficient neurofeedback training. We discuss experiments involving two different...

Genetic anaylsis of a disease resistance gene from loblolly pine

Science.gov (United States)

Yinghua Huang; Nili Jin; Alex Diner; Chuck Tauer; Yan Zhang; John Damicone

2003-01-01

Rapid advances in molecular genetics provide great opportunities for studies of host defense mechanisms. Examination of plant responses to disease at the cellular and molecular level permits both discovery of changes in gene expression in the tissues attacked by pathogens, and identification of genetic components involved in the interaction between host and pathogens....

Dispersal ability and habitat requirements determine landscape-level genetic patterns in desert aquatic insects.

Science.gov (United States)

Phillipsen, Ivan C; Kirk, Emily H; Bogan, Michael T; Mims, Meryl C; Olden, Julian D; Lytle, David A

2015-01-01

Species occupying the same geographic range can exhibit remarkably different population structures across the landscape, ranging from highly diversified to panmictic. Given limitations on collecting population-level data for large numbers of species, ecologists seek to identify proximate organismal traits-such as dispersal ability, habitat preference and life history-that are strong predictors of realized population structure. We examined how dispersal ability and habitat structure affect the regional balance of gene flow and genetic drift within three aquatic insects that represent the range of dispersal abilities and habitat requirements observed in desert stream insect communities. For each species, we tested for linear relationships between genetic distances and geographic distances using Euclidean and landscape-based metrics of resistance. We found that the moderate-disperser Mesocapnia arizonensis (Plecoptera: Capniidae) has a strong isolation-by-distance pattern, suggesting migration-drift equilibrium. By contrast, population structure in the flightless Abedus herberti (Hemiptera: Belostomatidae) is influenced by genetic drift, while gene flow is the dominant force in the strong-flying Boreonectes aequinoctialis (Coleoptera: Dytiscidae). The best-fitting landscape model for M. arizonensis was based on Euclidean distance. Analyses also identified a strong spatial scale-dependence, where landscape genetic methods only performed well for species that were intermediate in dispersal ability. Our results highlight the fact that when either gene flow or genetic drift dominates in shaping population structure, no detectable relationship between genetic and geographic distances is expected at certain spatial scales. This study provides insight into how gene flow and drift interact at the regional scale for these insects as well as the organisms that share similar habitats and dispersal abilities. © 2014 John Wiley & Sons Ltd.

X-ray induced specific locus mutations in the ad-3 region of two-component heterokaryons of neurospora crassa

International Nuclear Information System (INIS)

Serres, F.J. de; Miller, I.R.

1988-01-01

The basis for the reduced growth rates of heterokaryons between strains carrying nonallelic combinations of gene/point mutations and multilocus deletion mutations has been investigated by a simple genetic test. The growth rates of forced 2-component heterokaryons (dikaryons) between multilocus deletion mutations were compared with forced 3-component heterokaryons (trikaryons) containing an ad-3A R ad-3B R double mutant as their third component. Since the third component has no genetic damage at other loci immediately adjacent to the ad-3A or ad-3B locus, the growth rate on minimal medium depends on the functional activity of the unaltered ad-3A and ad-3B loci in the first two components. Tests in the present experiments have shown the ad-3 IR mutations result not only in inactivation of the ad-3 loci by multilocus deletion byt also, in many cases, in partial gene inactivation by an unknown mechanisms at other loci in the immediately adacent regions. The heterozygous effects observed in our present experiments with multilocus deletions in Neurospora can be explained either by a spreading-type position effect of the type found by others in Drosophila, mice, Oenothera and Aspergillus or by undetected genetic damage in the immediately adjacent genetic regions. (author). 18 refs.; 8 figs.; 2 tabs

Ligand-binding sites in human serum amyloid P component

DEFF Research Database (Denmark)

Heegaard, N.H.H.; Heegaard, Peter M. H.; Roepstorff, P.

1996-01-01

Amyloid P component (AP) is a naturally occurring glycoprotein that is found in serum and basement membranes, AP is also a component of all types of amyloid, including that found in individuals who suffer from Alzheimer's disease and Down's syndrome. Because AP has been found to bind strongly...

Forward Genetic Approaches for Elucidation of Novel Regulators of Lyme Arthritis Severity

Directory of Open Access Journals (Sweden)

Kenneth K.C. Bramwell

2014-06-01

Full Text Available Patients experiencing natural infection with Borrelia burgdorferi display a spectrum of associated symptoms and severity, strongly implicating the impact of genetically determined host factors in the pathogenesis of Lyme disease. Herein, we provide a summary of the host genetic factors that have been demonstrated to influence the severity and chronicity of Lyme arthritis symptoms, and a review of the resources available, current progress, and added value of a forward genetic approach for identification of novel genetic regulators.

Genetic Architecture of Group A Streptococcal Necrotizing Soft Tissue Infections in the Mouse

DEFF Research Database (Denmark)

Chella Krishnan, Karthickeyan; Mukundan, Santhosh; Alagarsamy, Jeyashree

2016-01-01

Host genetic variations play an important role in several pathogenic diseases, and we have previously provided strong evidences that these genetic variations contribute significantly to differences in susceptibility and clinical outcomes of invasive Group A Streptococcus (GAS) infections, includi...

Genetic analysis of body weight in South African Angora kids and ...

African Journals Online (AJOL)

Variance and covariance components and ratios pertaining to direct additive genetic variation, maternal additive genetic variation, maternal permanent environmental variation, and the relationship between direct and maternal effects for birth weight (BW; kg), weaning weight (WW; kg) and body weight at 8, 12 and 16 ...

Genetic algorithms and Monte Carlo simulation for optimal plant design

International Nuclear Information System (INIS)

Cantoni, M.; Marseguerra, M.; Zio, E.

2000-01-01

We present an approach to the optimal plant design (choice of system layout and components) under conflicting safety and economic constraints, based upon the coupling of a Monte Carlo evaluation of plant operation with a Genetic Algorithms-maximization procedure. The Monte Carlo simulation model provides a flexible tool, which enables one to describe relevant aspects of plant design and operation, such as standby modes and deteriorating repairs, not easily captured by analytical models. The effects of deteriorating repairs are described by means of a modified Brown-Proschan model of imperfect repair which accounts for the possibility of an increased proneness to failure of a component after a repair. The transitions of a component from standby to active, and vice versa, are simulated using a multiplicative correlation model. The genetic algorithms procedure is demanded to optimize a profit function which accounts for the plant safety and economic performance and which is evaluated, for each possible design, by the above Monte Carlo simulation. In order to avoid an overwhelming use of computer time, for each potential solution proposed by the genetic algorithm, we perform only few hundreds Monte Carlo histories and, then, exploit the fact that during the genetic algorithm population evolution, the fit chromosomes appear repeatedly many times, so that the results for the solutions of interest (i.e. the best ones) attain statistical significance

Genetically Modified Foods and Consumer Perspective.

Science.gov (United States)

Boccia, Flavio; Sarnacchiaro, Pasquale

2015-01-01

Genetically modified food is able to oppose the world's hunger and preserve the environment, even if the patents in this matter are symptomatic of several doubts. And also, transgenic consumption causes problems and skepticism among consumers in several European countries, but above all in Italy, where there is a strong opposition over recent years. So, the present study conducted a research to study the consumption of genetically modified food products by Italian young generation. This research presented the following purposes: firstly, to analyze genetically modified products' consumption among a particular category of consumers; secondly, to implement a quantitative model to understand behaviour about this particular kind of consumption and identify the factors that determine their purchase. The proposed model shows that transgenic consumption is especially linked to knowledge and impact on environment and mankind's health.

Genetic and environmental sources of individual differences in views on aging.

Science.gov (United States)

Kornadt, Anna E; Kandler, Christian

2017-06-01

Views on aging are central psychosocial variables in the aging process, but knowledge about their determinants is still fragmental. Thus, the authors investigated the degree to which genetic and environmental factors contribute to individual differences in various domains of views on aging (wisdom, work, fitness, and family), and whether these variance components vary across ages. They analyzed data from 350 monozygotic and 322 dizygotic twin pairs from the Midlife Development in the U.S. (MIDUS) study, aged 25-74. Individual differences in views on aging were mainly due to individual-specific environmental and genetic effects. However, depending on the domain, genetic and environmental contributions to the variance differed. Furthermore, for some domains, variability was larger for older participants; this was attributable to increases in environmental components. This study extends research on genetic and environmental sources of psychosocial variables and stimulates future studies investigating the etiology of views on aging across the life span. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

A Novel Multiscale Ensemble Carbon Price Prediction Model Integrating Empirical Mode Decomposition, Genetic Algorithm and Artificial Neural Network

Directory of Open Access Journals (Sweden)

Bangzhu Zhu

2012-02-01

Full Text Available Due to the movement and complexity of the carbon market, traditional monoscale forecasting approaches often fail to capture its nonstationary and nonlinear properties and accurately describe its moving tendencies. In this study, a multiscale ensemble forecasting model integrating empirical mode decomposition (EMD, genetic algorithm (GA and artificial neural network (ANN is proposed to forecast carbon price. Firstly, the proposed model uses EMD to decompose carbon price data into several intrinsic mode functions (IMFs and one residue. Then, the IMFs and residue are composed into a high frequency component, a low frequency component and a trend component which have similar frequency characteristics, simple components and strong regularity using the fine-to-coarse reconstruction algorithm. Finally, those three components are predicted using an ANN trained by GA, i.e., a GAANN model, and the final forecasting results can be obtained by the sum of these three forecasting results. For verification and testing, two main carbon future prices with different maturity in the European Climate Exchange (ECX are used to test the effectiveness of the proposed multiscale ensemble forecasting model. Empirical results obtained demonstrate that the proposed multiscale ensemble forecasting model can outperform the single random walk (RW, ARIMA, ANN and GAANN models without EMD preprocessing and the ensemble ARIMA model with EMD preprocessing.

Effects of Interaction Imbalance in a Strongly Repulsive One-Dimensional Bose Gas

Science.gov (United States)

Barfknecht, R. E.; Foerster, A.; Zinner, N. T.

2018-05-01

We calculate the spatial distributions and the dynamics of a few-body two-component strongly interacting Bose gas confined to an effectively one-dimensional trapping potential. We describe the densities for each component in the trap for different interaction and population imbalances. We calculate the time evolution of the system and show that, for a certain ratio of interactions, the minority population travels through the system as an effective wave packet.

Buffering mechanisms in aging: a systems approach toward uncovering the genetic component of aging.

Directory of Open Access Journals (Sweden)

Aviv Bergman

2007-08-01

Full Text Available An unrealized potential to understand the genetic basis of aging in humans, is to consider the immense survival advantage of the rare individuals who live 100 years or more. The Longevity Gene Study was initiated in 1998 at the Albert Einstein College of Medicine to investigate longevity genes in a selected population: the "oldest old" Ashkenazi Jews, 95 years of age and older, and their children. The study proved the principle that some of these subjects are endowed with longevity-promoting genotypes. Here we reason that some of the favorable genotypes act as mechanisms that buffer the deleterious effect of age-related disease genes. As a result, the frequency of deleterious genotypes may increase among individuals with extreme lifespan because their protective genotype allows disease-related genes to accumulate. Thus, studies of genotypic frequencies among different age groups can elucidate the genetic determinants and pathways responsible for longevity. Borrowing from evolutionary theory, we present arguments regarding the differential survival via buffering mechanisms and their target age-related disease genes in searching for aging and longevity genes. Using more than 1,200 subjects between the sixth and eleventh decades of life (at least 140 subjects in each group, we corroborate our hypotheses experimentally. We study 66 common allelic site polymorphism in 36 candidate genes on the basis of their phenotype. Among them we have identified a candidate-buffering mechanism and its candidate age-related disease gene target. Previously, the beneficial effect of an advantageous cholesteryl ester transfer protein (CETP-VV genotype on lipoprotein particle size in association with decreased metabolic and cardiovascular diseases, as well as with better cognitive function, have been demonstrated. We report an additional advantageous effect of the CETP-VV (favorable genotype in neutralizing the deleterious effects of the lipoprotein(a (LPA gene

Strong Genetic Differentiation of Submerged Plant Populations across Mountain Ranges: Evidence from Potamogeton pectinatus in Iran.

Science.gov (United States)

Abbasi, Shabnam; Afsharzadeh, Saeed; Saeidi, Hojjatollah; Triest, Ludwig

2016-01-01

Biogeographic barriers for freshwater biota can be effective at various spatial scales. At the largest spatial scale, freshwater organisms can become genetically isolated by their high mountain ranges, vast deserts, and inability to cross oceans. Isolation by distance of aquatic plants is expected to be stronger across than alongside mountain ridges whereas the heterogeneity of habitats among populations and temporary droughts may influence connectivity and hamper dispersal. Suitable aquatic plant habitats became reduced, even for the widespread submerged Potamogeton pectinatus L. (also named Stuckenia pectinata) giving structure to various aquatic habitats. We compared the level of genetic diversity in a heterogeneous series of aquatic habitats across Iran and tested their differentiation over distances and across mountain ranges (Alborz and Zagros) and desert zones (Kavir), with values obtained from temperate region populations. The diversity of aquatic ecosystems across and along large geographic barriers provided a unique ecological situation within Iran. P. pectinatus were considered from thirty-six sites across Iran at direct flight distances ranging from 20 to 1,200 km. Nine microsatellite loci revealed a very high number of alleles over all sites. A PCoA, NJT clustering and STRUCTURE analysis revealed a separate grouping of individuals of southeastern Iranian sites and was confirmed by their different nuclear ITS and cpDNA haplotypes thereby indicating an evolutionary significant unit (ESU). At the level of populations, a positive correlation between allelic differentiation Dest with geographic distance was found. Individual-based STRUCTURE analysis over 36 sites showed 7 genetic clusters. FST and RST values for ten populations reached 0.343 and 0.521, respectively thereby indicating that allele length differences are more important and contain evolutionary information. Overall, higher levels of diversity and a stronger differentiation was revealed among

Genetics of Triglycerides and the Risk of Atherosclerosis.

Science.gov (United States)

Dron, Jacqueline S; Hegele, Robert A

2017-07-01

Plasma triglycerides are routinely measured with a lipid profile, and elevated plasma triglycerides are commonly encountered in the clinic. The confounded nature of this trait, which is correlated with numerous other metabolic perturbations, including depressed high-density lipoprotein cholesterol (HDL-C), has thwarted efforts to directly implicate triglycerides as causal in atherogenesis. Human genetic approaches involving large-scale populations and high-throughput genomic assessment under a Mendelian randomization framework have undertaken to sort out questions of causality. We review recent large-scale meta-analyses of cohorts and population-based sequencing studies designed to address whether common and rare variants in genes whose products are determinants of plasma triglycerides are also associated with clinical cardiovascular endpoints. The studied loci include genes encoding lipoprotein lipase and proteins that interact with it, such as apolipoprotein (apo) A-V, apo C-III and angiopoietin-like proteins 3 and 4, and common polymorphisms identified in genome-wide association studies. Triglyceride-raising variant alleles of these genes showed generally strong associations with clinical cardiovascular endpoints. However, in most cases, a second lipid disturbance-usually depressed HDL-C-was concurrently associated. While the findings collectively shift our understanding towards a potential causal role for triglycerides, we still cannot rule out the possibilities that triglycerides are a component of a joint phenotype with low HDL-C or that they are but markers of deeper causal metabolic disturbances that are not routinely measured in epidemiological-scale genetic studies.

On indigenous production, genetic diversity and crop ecology of enset (Ensete ventricosum (Welw.) Cheesman)

NARCIS (Netherlands)

Tsegaye, A.

2002-01-01

Statistics for Learning Genetics

Science.gov (United States)

Charles, Abigail Sheena

This study investigated the knowledge and skills that biology students may need to help them understand statistics/mathematics as it applies to genetics. The data are based on analyses of current representative genetics texts, practicing genetics professors' perspectives, and more directly, students' perceptions of, and performance in, doing statistically-based genetics problems. This issue is at the emerging edge of modern college-level genetics instruction, and this study attempts to identify key theoretical components for creating a specialized biological statistics curriculum. The goal of this curriculum will be to prepare biology students with the skills for assimilating quantitatively-based genetic processes, increasingly at the forefront of modern genetics. To fulfill this, two college level classes at two universities were surveyed. One university was located in the northeastern US and the other in the West Indies. There was a sample size of 42 students and a supplementary interview was administered to a select 9 students. Interviews were also administered to professors in the field in order to gain insight into the teaching of statistics in genetics. Key findings indicated that students had very little to no background in statistics (55%). Although students did perform well on exams with 60% of the population receiving an A or B grade, 77% of them did not offer good explanations on a probability question associated with the normal distribution provided in the survey. The scope and presentation of the applicable statistics/mathematics in some of the most used textbooks in genetics teaching, as well as genetics syllabi used by instructors do not help the issue. It was found that the text books, often times, either did not give effective explanations for students, or completely left out certain topics. The omission of certain statistical/mathematical oriented topics was seen to be also true with the genetics syllabi reviewed for this study. Nonetheless

Environmental change, phenotypic plasticity, and genetic compensation.

Science.gov (United States)

Grether, Gregory F

2005-10-01

When a species encounters novel environmental conditions, some phenotypic characters may develop differently than in the ancestral environment. Most environmental perturbations of development are likely to reduce fitness, and thus selection would usually be expected to favor genetic changes that restore the ancestral phenotype. I propose the term "genetic compensation" to refer to this form of adaptive evolution. Genetic compensation is a subset of genetic accommodation and the reverse of genetic assimilation. When genetic compensation has occurred along a spatial environmental gradient, the mean trait values of populations in different environments may be more similar in the field than when representatives of the same populations are raised in a common environment (i.e., countergradient variation). If compensation is complete, genetic divergence between populations may be cryptic, that is, not detectable in the field. Here I apply the concept of genetic compensation to three examples involving carotenoid-based sexual coloration and then use these and other examples to discuss the concept in a broader context. I show that genetic compensation may lead to a cryptic form of reproductive isolation between populations evolving in different environments, may explain some puzzling cases in which heritable traits exposed to strong directional selection fail to show the expected evolutionary response, and may complicate efforts to monitor populations for signs of environmental deterioration.

Estimates of genetic parameters, genetic trends, and inbreeding in a crossbred dairy sheep research flock in the United States.

Science.gov (United States)

Murphy, T W; Berger, Y M; Holman, P W; Baldin, M; Burgett, R L; Thomas, D L

2017-10-01

For the past 2 decades, the Spooner Agriculture Research Station (ARS) of the University of Wisconsin-Madison operated the only dairy sheep research flock in North America. The objectives of the present study were to 1) obtain estimates of genetic parameters for lactation and reproductive traits in dairy ewes, 2) estimate the amount of genetic change in these traits over time, and 3) quantify the level of inbreeding in this flock over the last 20 yr. Multiple-trait repeatability models (MTRM) were used to analyze ewe traits through their first 6 parities. The first MTRM jointly analyzed milk (180-d-adjusted milk yield [180d MY]), fat (180-d-adjusted fat yield [180d FY]), and protein (180-d-adjusted protein yield [180d PY]) yields adjusted to 180 d of lactation; number of lambs born per ewe lambing (NLB); and lactation average test-day somatic cell score (LSCS). A second MTRM analyzed 180d MY, NLB, LSCS, and percentage milk fat (%F) and percentage milk protein (%P). The 3 yield traits were moderately heritable (0.26 to 0.32) and strongly genetically correlated (0.91 to 0.96). Percentage milk fat and %P were highly heritable (0.53 and 0.61, respectively) and moderately genetically correlated (0.61). Milk yield adjusted to 180 d was negatively genetically correlated with %F and %P (-0.31 and -0.34, respectively). Ewe prolificacy was not significantly ( > 0.67) genetically correlated with yield traits, %P, or LSCS but lowly negatively correlated with %F (-0.26). Lactation somatic cell score was unfavorably genetically correlated with yield traits (0.28 to 0.39) but not significantly ( > 0.09) correlated with %F, %P, and NLB. Within-trait multiple-trait models through the first 4 parities revealed that 180d MY, 180d FY, 180d PY, %F, and %P were strongly genetically correlated across parity (0.67 to 1.00). However, the genetic correlations across parity for NLB and LSCS were somewhat lower (0.51 to 0.96). Regressing predicted breeding values for 180d MY, without and with

Concordance between botanical groups and genetic diversity in peanut

Directory of Open Access Journals (Sweden)

Ingrid Pinheiro Machado

Full Text Available ABSTRACT The aims of this study were to characterize peanut accessions of germplasm collection of the CCA/UFC and check consistency between the pre-existing botanical groups to estimates of genetic diversity. For this were conducted a trial with 43 accessions of peanut in a randomized block design with three replications. To characterization were used 21 morphological descriptors, where revealed large genetic variation. The mass hundred grains trait showed the main discriminating factors, with relative percentage of 22.1%. The cluster obtained with the linkage complete method, it was possible to view the dendrogram the formation of seven groups based on the Mahalanobis distance. By principal components analysis was identified phenotypic diversity among genotypes. The first three components explained 81% of the total variation. Subsequently, built a three-dimensional scatter chart for access of visualization, eight groups being formed. There was medium magnitude of agreement between the botanical groups and genetic diversity, both by the dendrogram and graphic dispersion proving the dissimilarity between genotypes of different botanic groups. Therefore, crossings between group access botanical Spanish or Valencia with those belonging to the Virginia group should generate segregating populations with high genetic potential.

High heritability and genetic correlation of intravenous glucose- and tolbutamide-induced insulin secretion among non-diabetic family members of type 2 diabetic patients

DEFF Research Database (Denmark)

Gjesing, Anette Marianne Prior; Hornbak, Malene; Allin, Kristine H.

2014-01-01

∈±∈SE: 0.49∈±∈0.14) and beta cell responsiveness to glucose (h 2∈±∈SE: 0.66∈±∈0.12). Additionally, strong genetic correlations were found between measures of beta cell response after glucose and tolbutamide stimulation, with correlation coefficients ranging from 0.77 to 0.88. Furthermore, we identified......Aims/hypothesis: The aim of this study was to estimate the heritability of quantitative measures of glucose regulation obtained from a tolbutamide-modified frequently sampled IVGTT (t-FSIGT) and to correlate the heritability of the glucose-stimulated beta cell response to the tolbutamide...... after tolbutamide (DIT), insulin sensitivity (SI), glucose effectiveness (SG) and beta cell responsiveness to glucose were calculated. A polygenic variance component model was used to estimate heritability, genetic correlations and associations. Results: We found high heritabilities for acute insulin...

Genetic HLA Associations in Complex Regional Pain Syndrome With and Without Dystonia

NARCIS (Netherlands)

van Rooijen, D.E.; Roelen, D.L.; Verduijn, W.; Haasnoot, G.W.; Huygen, F.J.P.M.; Perez, R.S.G.M.; Claas, F.H.J.; Marinus, J.; van Hilten, J.J.; van den Maagdenberg, A.M.J.M.

2012-01-01

We previously showed evidence for a genetic association of the human leukocyte antigen (HLA) system and complex regional pain syndrome (CRPS) with dystonia. Involvement of the HLA system suggests that CRPS has a genetic component with perturbed regulation of inflammation and neuroplasticity as

Sleep Reactivity and Insomnia: Genetic and Environmental Influences

Science.gov (United States)

Drake, Christopher L.; Friedman, Naomi P.; Wright, Kenneth P.; Roth, Thomas

2011-01-01

Study Objectives: Determine the genetic and environmental contributions to sleep reactivity and insomnia. Design: Population-based twin cohort. Participants: 1782 individual twins (988 monozygotic or MZ; 1,086 dizygotic or DZ), including 744 complete twin pairs (377 MZ and 367 DZ). Mean age was 22.5 ± 2.8 years; gender distribution was 59% women. Measurements: Sleep reactivity was measured using the Ford Insomnia Response to Stress Test (FIRST). The criterion for insomnia was having difficulty falling asleep, staying asleep, or nonrefreshing sleep “usually or always” for ≥ 1 month, with at least “somewhat” interference with daily functioning. Results: The prevalence of insomnia was 21%. Heritability estimates for sleep reactivity were 29% for females and 43% for males. The environmental variance for sleep reactivity was greater for females and entirely due to nonshared effects. Insomnia was 43% to 55% heritable for males and females, respectively; the sex difference was not significant. The genetic variances in insomnia and FIRST scores were correlated (r = 0.54 in females, r = 0.64 in males), as were the environmental variances (r = 0.32 in females, r = 0.37 in males). In terms of individual insomnia symptoms, difficulty staying asleep (25% to 35%) and nonrefreshing sleep (34% to 35%) showed relatively more genetic influences than difficulty falling asleep (0%). Conclusions: Sleep reactivity to stress has a substantial genetic component, as well as an environmental component. The finding that FIRST scores and insomnia symptoms share genetic influences is consistent with the hypothesis that sleep reactivity may be a genetic vulnerability for developing insomnia. Citation: Drake CL; Friedman NP; Wright KP; Roth T. Sleep reactivity and insomnia: genetic and environmental influences. SLEEP 2011;34(9):1179-1188. PMID:21886355

New developments in genetics of myositis.

Science.gov (United States)

Rothwell, Simon; Lamb, Janine A; Chinoy, Hector

2016-11-01

This article reviews the advances that have been made in our understanding of the genetics of the idiopathic inflammatory myopathies (IIM) in the past 2 years, with a particular focus on polymyositis, dermatomyositis and inclusion body myositis. Two large human leukocyte antigen (HLA) imputation studies have confirmed a strong association with the 8.1 ancestral haplotype in clinical subgroups of myositis and suggest multiple independent associations on this haplotype. Risk in these genes may be due to specific amino acid positions within the peptide-binding grooves of HLA molecules. A large genetic study in 2566 IIM patients revealed associations such as PTPN22, STAT4, UBE2L3 and BLK, which overlap with risk variants reported in other seropositive autoimmune diseases. There is also evidence of different genetic architectures in clinical subgroups of IIM. Candidate gene studies in the Japanese and Chinese populations have replicated previous IIM associations which suggest common aetiology between ethnicities. International collaborations have facilitated large genetic studies in IIM that have revealed much about the genetics of this rare complex disease both within the HLA region and genome-wide. Future approaches, such as sequencing and trans-ethnic meta-analyses, will advance our knowledge of IIM genetics.

Ethics of genetic counseling--basic concepts and relevance to Islamic communities.

Science.gov (United States)

El-Hazmi, Mohsen A F

2004-01-01

Scientific advances and technical developments in the field of laboratory diagnosis and their practical applications have raised ethical issues linked to religion, beliefs, lifestyle and traditions prevailing in different communities. Some of these are pertinent to genetic screening at various stages of life, prenatal diagnosis and the right of the genetically affected fetus to live--all aspects relevant to inbreeding marriages. Of relevance are medical and ethical principles based on professional responsibility. These ideological and social aspects encounter the challenges of science and its applications in the health field, which are linked, directly or indirectly, to scientific achievements and applications related to human genetics. Analysis of the human genome and identification of its sequence, and chemical components, and theories arising from connection of human genome components in health and disease conditions, have led to global requirements to outline legal aspects and ethical principles in relation to diagnosis, prevention and health care. This paper presents basic aspects of disseminating genetic information, guiding the individual, the couple, or the concerned family through genetically induced ill health and methods of control and prevention. The paper discusses the elements and manner and presents details of the application of genetic counseling in Islamic communities in light of scientific, religious, social and legal aspects in the Islamic arena.

Genetic susceptibility to chronic wasting disease in free-ranging white-tailed deer: complement component C1q and Prnp polymorphisms

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Blanchong, Julie A.; Heisey, Dennis M.; Scribner, Kim T.; Libants, Scot V.; Johnson, Chad; Aiken, Judd M.; Langenberg, Julia A.; Samuel, Michael D.

2009-01-01

The genetic basis of susceptibility to chronic wasting disease (CWD) in free-ranging cervids is of great interest. Association studies of disease susceptibility in free-ranging populations, however, face considerable challenges including: the need for large sample sizes when disease is rare, animals of unknown pedigree create a risk of spurious results due to population admixture, and the inability to control disease exposure or dose. We used an innovative matched case–control design and conditional logistic regression to evaluate associations between polymorphisms of complement C1q and prion protein (Prnp) genes and CWD infection in white-tailed deer from the CWD endemic area in south-central Wisconsin. To reduce problems due to admixture or disease-risk confounding, we used neutral genetic (microsatellite) data to identify closely related CWD-positive (n = 68) and CWD-negative (n = 91) female deer to serve as matched cases and controls. Cases and controls were also matched on factors (sex, location, age) previously demonstrated to affect CWD infection risk. For Prnp, deer with at least one Serine (S) at amino acid 96 were significantly less likely to be CWD-positive relative to deer homozygous for Glycine (G). This is the first characterization of genes associated with the complement system in white-tailed deer. No tests for association between any C1q polymorphism and CWD infection were significant at p of CWD infection in deer with at least one Glycine (G) at amino acid 56 of the C1qC gene. While we documented numerous amino acid polymorphisms in C1q genes none appear to be strongly associated with CWD susceptibility.

Genetic Characterization of Dog Personality Traits.

Science.gov (United States)

Ilska, Joanna; Haskell, Marie J; Blott, Sarah C; Sánchez-Molano, Enrique; Polgar, Zita; Lofgren, Sarah E; Clements, Dylan N; Wiener, Pamela

2017-06-01

The genetic architecture of behavioral traits in dogs is of great interest to owners, breeders, and professionals involved in animal welfare, as well as to scientists studying the genetics of animal (including human) behavior. The genetic component of dog behavior is supported by between-breed differences and some evidence of within-breed variation. However, it is a challenge to gather sufficiently large datasets to dissect the genetic basis of complex traits such as behavior, which are both time-consuming and logistically difficult to measure, and known to be influenced by nongenetic factors. In this study, we exploited the knowledge that owners have of their dogs to generate a large dataset of personality traits in Labrador Retrievers. While accounting for key environmental factors, we demonstrate that genetic variance can be detected for dog personality traits assessed using questionnaire data. We identified substantial genetic variance for several traits, including fetching tendency and fear of loud noises, while other traits revealed negligibly small heritabilities. Genetic correlations were also estimated between traits; however, due to fairly large SEs, only a handful of trait pairs yielded statistically significant estimates. Genomic analyses indicated that these traits are mainly polygenic, such that individual genomic regions have small effects, and suggested chromosomal associations for six of the traits. The polygenic nature of these traits is consistent with previous behavioral genetics studies in other species, for example in mouse, and confirms that large datasets are required to quantify the genetic variance and to identify the individual genes that influence behavioral traits. Copyright © 2017 by the Genetics Society of America.

Disentangling the roles of natural selection and genetic drift in shaping variation at MHC immunity genes.

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Sutton, Jolene T; Nakagawa, Shinichi; Robertson, Bruce C; Jamieson, Ian G

2011-11-01

The major histocompatibility complex (MHC) forms an integral component of the vertebrate immune response and, due to strong selection pressures, is one of the most polymorphic regions of the entire genome. Despite over 15 years of research, empirical studies offer highly contradictory explanations of the relative roles of different evolutionary forces, selection and genetic drift, acting on MHC genes during population bottlenecks. Here, we take a meta-analytical approach to quantify the results of studies into the effects of bottlenecks on MHC polymorphism. We show that the consequences of selection acting on MHC loci prior to a bottleneck event, combined with drift during the bottleneck, will result in overall loss of MHC polymorphism that is ∼15% greater than loss of neutral genetic diversity. These results are counter to general expectations that selection should maintain MHC polymorphism, but do agree with the results of recent simulation models and at least two empirical studies. Notably, our results suggest that negative frequency-dependent selection could be more important than overdominance for maintaining high MHC polymorphism in pre-bottlenecked populations. © 2011 Blackwell Publishing Ltd.

Estimation of Genetic Variance Components Including Mutation and Epistasis using Bayesian Approach in a Selection Experiment on Body Weight in Mice

DEFF Research Database (Denmark)

Widyas, Nuzul; Jensen, Just; Nielsen, Vivi Hunnicke

Selection experiment was performed for weight gain in 13 generations of outbred mice. A total of 18 lines were included in the experiment. Nine lines were allotted to each of the two treatment diets (19.3 and 5.1 % protein). Within each diet three lines were selected upwards, three lines were...... selected downwards and three lines were kept as controls. Bayesian statistical methods are used to estimate the genetic variance components. Mixed model analysis is modified including mutation effect following the methods by Wray (1990). DIC was used to compare the model. Models including mutation effect...... have better fit compared to the model with only additive effect. Mutation as direct effect contributes 3.18% of the total phenotypic variance. While in the model with interactions between additive and mutation, it contributes 1.43% as direct effect and 1.36% as interaction effect of the total variance...

Strong population genetic structuring in an annual fish, Nothobranchius furzeri, suggests multiple savannah refugia in southern Mozambique

Czech Academy of Sciences Publication Activity Database

Bartáková, V.; Reichard, M.; Janko, Karel; Polačik, M.; Blažek, R.; Reichwald, K.; Cellerino, A.; Bryja, J.

2013-01-01

Roč. 13, č. 196 (2013), s. 1-15 ISSN 1471-2148 Institutional support: RVO:67985904 Keywords : temporary pool * pyhlogeography * population genetics Subject RIV: EG - Zoology Impact factor: 3.407, year: 2013 http://www.biomedcentral.com/1471-2148/13/196

Evolutionary dynamics of fluctuating populations with strong mutualism

Science.gov (United States)

Chotibut, Thiparat; Nelson, David

2013-03-01

Evolutionary game theory with finite interacting populations is receiving increased attention, including subtle phenomena associated with number fluctuations, i.e., ``genetic drift.'' Models of cooperation and competition often utilize a simplified Moran model, with a strictly fixed total population size. We explore a more general evolutionary model with independent fluctuations in the numbers of two distinct species, in a regime characterized by ``strong mutualism.'' The model has two absorbing states, each corresponding to fixation of one of the two species, and allows exploration of the interplay between growth, competition, and mutualism. When mutualism is favored, number fluctuations eventually drive the system away from a stable fixed point, characterized by cooperation, to one of the absorbing states. Well-mixed populations will thus be taken over by a single species in a finite time, despite the bias towards cooperation. We calculate both the fixation probability and the mean fixation time as a function of the initial conditions and carrying capacities in the strong mutualism regime, using the method of matched asymptotic expansions. Our results are compared to computer simulations.

The plant pathogen Pseudomonas syringae pv. tomato is genetically monomorphic and under strong selection to evade tomato immunity.

Directory of Open Access Journals (Sweden)

Rongman Cai

2011-08-01

Full Text Available Recently, genome sequencing of many isolates of genetically monomorphic bacterial human pathogens has given new insights into pathogen microevolution and phylogeography. Here, we report a genome-based micro-evolutionary study of a bacterial plant pathogen, Pseudomonas syringae pv. tomato. Only 267 mutations were identified between five sequenced isolates in 3,543,009 nt of analyzed genome sequence, which suggests a recent evolutionary origin of this pathogen. Further analysis with genome-derived markers of 89 world-wide isolates showed that several genotypes exist in North America and in Europe indicating frequent pathogen movement between these world regions. Genome-derived markers and molecular analyses of key pathogen loci important for virulence and motility both suggest ongoing adaptation to the tomato host. A mutational hotspot was found in the type III-secreted effector gene hopM1. These mutations abolish the cell death triggering activity of the full-length protein indicating strong selection for loss of function of this effector, which was previously considered a virulence factor. Two non-synonymous mutations in the flagellin-encoding gene fliC allowed identifying a new microbe associated molecular pattern (MAMP in a region distinct from the known MAMP flg22. Interestingly, the ancestral allele of this MAMP induces a stronger tomato immune response than the derived alleles. The ancestral allele has largely disappeared from today's Pto populations suggesting that flagellin-triggered immunity limits pathogen fitness even in highly virulent pathogens. An additional non-synonymous mutation was identified in flg22 in South American isolates. Therefore, MAMPs are more variable than expected differing even between otherwise almost identical isolates of the same pathogen strain.

Genetic characteristics of Japanese clinical Listeria monocytogenes isolates.

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Satoko Miya

Full Text Available Listeria monocytogenes causes foodborne illnesses through consumption of ready-to-eat foods. Although 135-201annual listeriosis cases have been estimated in Japan, the details regarding the clinical isolates such as infection source, virulence level, and other genetic characteristics, are not known. In order to uncover the trends of listeriosis in Japan and use the knowledge for prevention measures to be taken, the genetic characteristics of the past human clinical isolates needs to be elucidated. For this purpose, multilocus tandem-repeat sequence analysis (MLTSA and multi-virulence-locus sequence typing (MVLST were used in this study. The clinical isolates showed a variety of genetically distant genotypes, indicating they were from sporadic cases. However, the MVLST profiles of 7 clinical isolates were identical to those of epidemic clone (EC I isolates, which have caused several serious outbreaks in other countries, suggesting the possibility that they have strong virulence potential and originated from a single outbreak. Moreover, 6 Japanese food isolates shared their genotypes with ECI isolates, indicating that there may be risks for listeriosis outbreak in Japan. This is the first investigational study on genetic characteristics of Japanese listeriosis isolates. The listeriosis cases happened in the past are presumably sporadic, but it is still possible that some isolates with strong virulence potential have caused listeriosis outbreaks, and future listeriosis risks also exist.

Bias, accuracy and impact of indirect genetic effects in infectious diseases

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Debby eLipschutz-Powell

2012-10-01

Full Text Available Selection for improved host response to infectious disease offers a desirable alternative to chemical treatment but has proven difficult in practice, due to low heritability estimates of disease traits. Disease data from field studies is often binary, indicating whether an individual has become infected or not following exposure to an infectious disease. Numerous studies have shown that from this data one can infer genetic variation in individuals’ underlying susceptibility. In a previous study, we showed that with an Indirect Genetic Effect (IGE model it is possible to capture some genetic variation in infectivity, if present, as well as in susceptibility. Infectivity is the propensity of transmitting infection upon contact with a susceptible individual. It is an important factor determining the severity of an epidemic. However, there are severe shortcomings with the Standard IGE models as they do not accommodate the dynamic nature of disease data. Here we adjust the Standard IGE model to (1 make expression of infectivity dependent on the individuals’ disease status (Case Model and (2 to include timing of infection (Case-ordered Model. The models are evaluated by comparing impact of selection, bias and accuracy of each model using simulated binary disease data. These were generated for populations with known variation in susceptibility and infectivity thus allowing comparisons between estimated and true breeding values. Overall the Case Model provided better estimates for host genetic susceptibility and infectivity compared to the Standard Model in terms of bias, impact and accuracy. Furthermore, these estimates were strongly influenced by epidemiological characteristics. However, surprisingly, the Case Ordered model performed considerably worse than the Standard and the Case Models, pointing towards limitations in incorporating disease dynamics into conventional variance component estimation methodology and software used in animal breeding.

General Methods for Evolutionary Quantitative Genetic Inference from Generalized Mixed Models.

Science.gov (United States)

de Villemereuil, Pierre; Schielzeth, Holger; Nakagawa, Shinichi; Morrissey, Michael

2016-11-01

Methods for inference and interpretation of evolutionary quantitative genetic parameters, and for prediction of the response to selection, are best developed for traits with normal distributions. Many traits of evolutionary interest, including many life history and behavioral traits, have inherently nonnormal distributions. The generalized linear mixed model (GLMM) framework has become a widely used tool for estimating quantitative genetic parameters for nonnormal traits. However, whereas GLMMs provide inference on a statistically convenient latent scale, it is often desirable to express quantitative genetic parameters on the scale upon which traits are measured. The parameters of fitted GLMMs, despite being on a latent scale, fully determine all quantities of potential interest on the scale on which traits are expressed. We provide expressions for deriving each of such quantities, including population means, phenotypic (co)variances, variance components including additive genetic (co)variances, and parameters such as heritability. We demonstrate that fixed effects have a strong impact on those parameters and show how to deal with this by averaging or integrating over fixed effects. The expressions require integration of quantities determined by the link function, over distributions of latent values. In general cases, the required integrals must be solved numerically, but efficient methods are available and we provide an implementation in an R package, QGglmm. We show that known formulas for quantities such as heritability of traits with binomial and Poisson distributions are special cases of our expressions. Additionally, we show how fitted GLMM can be incorporated into existing methods for predicting evolutionary trajectories. We demonstrate the accuracy of the resulting method for evolutionary prediction by simulation and apply our approach to data from a wild pedigreed vertebrate population. Copyright © 2016 de Villemereuil et al.

Genetic Variants of Angiotensin-Converting Enzyme Are Linked to Autism: A Case-Control Study.

Science.gov (United States)

Firouzabadi, Negar; Ghazanfari, Nima; Alavi Shoushtari, Ali; Erfani, Nasrallah; Fathi, Farshid; Bazrafkan, Mozhdeh; Bahramali, Ehsan

2016-01-01

Autism is a disease of complex nature with a significant genetic component. The importance of renin-angiotensin system (RAS) elements in cognition and behavior besides the interaction of angiotensin II (Ang II), the main product of angiotensin-converting enzyme (ACE), with neurotransmitters in CNS, especially dopamine, proposes the involvement of RAS in autism. Since the genetic architecture of autism has remained elusive, here we postulated that genetic variations in RAS are associated with autism. Considering the relation between the three polymorphisms of ACE (I/D, rs4343 and rs4291) with the level of ACE activity, we have investigated this association with autism, in a case-control study. Genotype and allele frequencies of polymorphisms were determined in DNAs extracted from venous blood of 120 autistic patients and their age and sex-matched healthy controls, using polymerase chain reaction (PCR) and PCR-restriction fragment length polymorphism (PCR-RFLP) methods. There were strong associations between both DD genotype of ACE I/D and the D allele, with autism (P = 0.006, OR = 2.9, 95% CI = 1.64-5.13 and P = 0.006, OR = 2.18, 95% CI = 1.37-3.48 respectively). Furthermore, a significant association between the G allele of rs4343 and autism was observed (P = 0.006, OR = 1.84, 95%CI = 1.26-2.67). Moreover, haplotype analysis revealed an association between DTG haplotype and autism (P = 0.008). Our data suggests the involvement of RAS genetic diversity in increasing the risk of autism.

Genetic Variants of Angiotensin-Converting Enzyme Are Linked to Autism: A Case-Control Study.

Directory of Open Access Journals (Sweden)

Negar Firouzabadi

Full Text Available Autism is a disease of complex nature with a significant genetic component. The importance of renin-angiotensin system (RAS elements in cognition and behavior besides the interaction of angiotensin II (Ang II, the main product of angiotensin-converting enzyme (ACE, with neurotransmitters in CNS, especially dopamine, proposes the involvement of RAS in autism. Since the genetic architecture of autism has remained elusive, here we postulated that genetic variations in RAS are associated with autism.Considering the relation between the three polymorphisms of ACE (I/D, rs4343 and rs4291 with the level of ACE activity, we have investigated this association with autism, in a case-control study. Genotype and allele frequencies of polymorphisms were determined in DNAs extracted from venous blood of 120 autistic patients and their age and sex-matched healthy controls, using polymerase chain reaction (PCR and PCR-restriction fragment length polymorphism (PCR-RFLP methods.There were strong associations between both DD genotype of ACE I/D and the D allele, with autism (P = 0.006, OR = 2.9, 95% CI = 1.64-5.13 and P = 0.006, OR = 2.18, 95% CI = 1.37-3.48 respectively. Furthermore, a significant association between the G allele of rs4343 and autism was observed (P = 0.006, OR = 1.84, 95%CI = 1.26-2.67. Moreover, haplotype analysis revealed an association between DTG haplotype and autism (P = 0.008.Our data suggests the involvement of RAS genetic diversity in increasing the risk of autism.

Genetic parameters and path analysis in cowpea genotypes grown in the Cerrado/Pantanal ecotone.

Science.gov (United States)

Lopes, K V; Teodoro, P E; Silva, F A; Silva, M T; Fernandes, R L; Rodrigues, T C; Faria, T C; Corrêa, A M

2017-05-18

Estimating genetic parameters in plant breeding allows us to know the population potential for selecting and designing strategies that can maximize the achievement of superior genotypes. The objective of this study was to evaluate the genetic potential of a population of 20 cowpea genotypes by estimating genetic parameters and path analysis among the traits to guide the selection strategies. The trial was conducted in randomized block design with four replications. Its morphophysiological components, components of green grain production and dry grain yield were estimated from genetic use and correlations between the traits. Phenotypic correlations were deployed through path analysis into direct and indirect effects of morphophysiological traits and yield components on dry grain yield. There were significant differences (P < 0.01) between the genotypes for most the traits, indicating the presence of genetic variability in the population and the possibility of practicing selection. The population presents the potential for future genetic breeding studies and is highly promising for the selection of traits dry grain yield, the number of grains per pod, and hundred grains mass. A number of grains per green pod is the main determinant trait of dry grain yield that is also influenced by the cultivar cycle and that the selection for the dry grain yield can be made indirectly by selecting the green pod mass and green pod length.

Evolutionary dynamics with fluctuating population sizes and strong mutualism

Science.gov (United States)

Chotibut, Thiparat; Nelson, David R.

2015-08-01

Game theory ideas provide a useful framework for studying evolutionary dynamics in a well-mixed environment. This approach, however, typically enforces a strictly fixed overall population size, deemphasizing natural growth processes. We study a competitive Lotka-Volterra model, with number fluctuations, that accounts for natural population growth and encompasses interaction scenarios typical of evolutionary games. We show that, in an appropriate limit, the model describes standard evolutionary games with both genetic drift and overall population size fluctuations. However, there are also regimes where a varying population size can strongly influence the evolutionary dynamics. We focus on the strong mutualism scenario and demonstrate that standard evolutionary game theory fails to describe our simulation results. We then analytically and numerically determine fixation probabilities as well as mean fixation times using matched asymptotic expansions, taking into account the population size degree of freedom. These results elucidate the interplay between population dynamics and evolutionary dynamics in well-mixed systems.

Evolutionary dynamics with fluctuating population sizes and strong mutualism.

Science.gov (United States)

Chotibut, Thiparat; Nelson, David R

2015-08-01

Game theory ideas provide a useful framework for studying evolutionary dynamics in a well-mixed environment. This approach, however, typically enforces a strictly fixed overall population size, deemphasizing natural growth processes. We study a competitive Lotka-Volterra model, with number fluctuations, that accounts for natural population growth and encompasses interaction scenarios typical of evolutionary games. We show that, in an appropriate limit, the model describes standard evolutionary games with both genetic drift and overall population size fluctuations. However, there are also regimes where a varying population size can strongly influence the evolutionary dynamics. We focus on the strong mutualism scenario and demonstrate that standard evolutionary game theory fails to describe our simulation results. We then analytically and numerically determine fixation probabilities as well as mean fixation times using matched asymptotic expansions, taking into account the population size degree of freedom. These results elucidate the interplay between population dynamics and evolutionary dynamics in well-mixed systems.

PRISM, Processing and Review Interface for Strong Motion Data Software

Science.gov (United States)

Kalkan, E.; Jones, J. M.; Stephens, C. D.; Ng, P.

2016-12-01

A continually increasing number of high-quality digital strong-motion records from stations of the National Strong Motion Project (NSMP) of the U.S. Geological Survey (USGS), as well as data from regional seismic networks within the U.S., calls for automated processing of strong-motion records with human review limited to selected significant or flagged records. The NSMP has developed the Processing and Review Interface for Strong Motion data (PRISM) software to meet this need. PRISM automates the processing of strong-motion records by providing batch-processing capabilities. The PRISM software is platform-independent (coded in Java), open-source, and does not depend on any closed-source or proprietary software. The software consists of two major components: a record processing engine composed of modules for each processing step, and a graphical user interface (GUI) for manual review and processing. To facilitate the use by non-NSMP earthquake engineers and scientists, PRISM (both its processing engine and GUI components) is easy to install and run as a stand-alone system on common operating systems such as Linux, OS X and Windows. PRISM was designed to be flexible and extensible in order to accommodate implementation of new processing techniques. Input to PRISM currently is limited to data files in the Consortium of Organizations for Strong-Motion Observation Systems (COSMOS) V0 format, so that all retrieved acceleration time series need to be converted to this format. Output products include COSMOS V1, V2 and V3 files as: (i) raw acceleration time series in physical units with mean removed (V1), (ii) baseline-corrected and filtered acceleration, velocity, and displacement time series (V2), and (iii) response spectra, Fourier amplitude spectra and common earthquake-engineering intensity measures (V3). A thorough description of the record processing features supported by PRISM is presented with examples and validation results. All computing features have been

Population Genetics of Three Dimensional Range Expansions

Science.gov (United States)

Lavrentovich, Maxim; Nelson, David

2014-03-01

We develop a simple model of genetic diversity in growing spherical cell clusters, where the growth is confined to the cluster surface. This kind of growth occurs in cells growing in soft agar, and can also serve as a simple model of avascular tumors. Mutation-selection balance in these radial expansions is strongly influenced by scaling near a neutral, voter model critical point and by the inflating frontier. We develop a scaling theory to describe how the dynamics of mutation-selection balance is cut off by inflation. Genetic drift, i.e., local fluctuations in the genetic diversity, also plays an important role, and can lead to the extinction even of selectively advantageous strains. We calculate this extinction probability, taking into account the effect of rough population frontiers.

Genetic and environmental contributions to body mass index: comparative analysis of monozygotic twins, dizygotic twins and same-age unrelated siblings.

Science.gov (United States)

Segal, N L; Feng, R; McGuire, S A; Allison, D B; Miller, S

2009-01-01

Earlier studies have established that a substantial percentage of variance in obesity-related phenotypes is explained by genetic components. However, only one study has used both virtual twins (VTs) and biological twins and was able to simultaneously estimate additive genetic, non-additive genetic, shared environmental and unshared environmental components in body mass index (BMI). Our current goal was to re-estimate four components of variance in BMI, applying a more rigorous model to biological and virtual multiples with additional data. Virtual multiples share the same family environment, offering unique opportunities to estimate common environmental influence on phenotypes that cannot be separated from the non-additive genetic component using only biological multiples. Data included 929 individuals from 164 monozygotic twin pairs, 156 dizygotic twin pairs, five triplet sets, one quadruplet set, 128 VT pairs, two virtual triplet sets and two virtual quadruplet sets. Virtual multiples consist of one biological child (or twins or triplets) plus one same-aged adoptee who are all raised together since infancy. We estimated the additive genetic, non-additive genetic, shared environmental and unshared random components in BMI using a linear mixed model. The analysis was adjusted for age, age(2), age(3), height, height(2), height(3), gender and race. Both non-additive genetic and common environmental contributions were significant in our model (P-valuesrole in BMI and that common environmental factors such as diet or exercise also affect BMI. This conclusion is consistent with our earlier study using a smaller sample and shows the utility of virtual multiples for separating non-additive genetic variance from common environmental variance.

Individual differences in P300 amplitude: a genetic study in adolescent twins

NARCIS (Netherlands)

van Beijsterveldt, C.E.M.; Molenaar, P.C.M.; de Geus, E.J.C.; Boomsma, D.I.

1998-01-01

Using quantitative genetic research designs, we decomposed phenotypic variance in P300 parameters into genetic and environmental components. The twin method was used to carry out this decomposition. Event related potentials (ERPs) were measured during a visual oddball paradigm in a sample of 213

Individual differences in P300 amplitude: A genetic study in adolescent twins.

NARCIS (Netherlands)

van Beijsterveld, C.E.M.; Molenaar, P.C.M.; de Geus, E.J.C.; Boomsma, D.I.

1998-01-01

Using quantitative genetic research designs, we decomposed phenotypic variance in P300 parameters into genetic and environmental components. The twin method was used to carry out this decomposition. Event related potentials (ERPs) were measured during a visual oddball paradigm in a sample of 213

Selective principal component regression analysis of fluorescence hyperspectral image to assess aflatoxin contamination in corn

Science.gov (United States)

Selective principal component regression analysis (SPCR) uses a subset of the original image bands for principal component transformation and regression. For optimal band selection before the transformation, this paper used genetic algorithms (GA). In this case, the GA process used the regression co...

How Should Clinicians Counsel a Woman with a Strong Family History of Early-Onset Alzheimer's Disease about Her Pregnancy?

Science.gov (United States)

Mapes, Marianna V; O'Brien, Barbara M; King, Louise P

2017-07-01

Counseling patients regarding the benefits, harms, and dilemmas of genetic testing is one of the greatest ethical challenges facing reproductive medicine today. With or without test results, clinicians grapple with how to communicate potential genetic risks as patients weigh their reproductive options. Here, we consider a case of a woman with a strong family history of early-onset Alzheimer's disease (EOAD). She is early in her pregnancy and unsure about learning her own genetic status. We address the ethical ramifications of each of her options, which include genetic testing, genetic counseling, and termination versus continuation of the pregnancy. Our analysis foregrounds clinicians' role in helping to ensure autonomous decision making as the patient reflects on these clinical options in light of her goals and values. © 2017 American Medical Association. All Rights Reserved.

Genetic structure of the Caribbean giant barrel sponge Xestospongia muta using the I3-M11 partition of COI

Science.gov (United States)

López-Legentil, S.; Pawlik, J. R.

2009-03-01

In recent years, reports of sponge bleaching, disease, and subsequent mortality have increased alarmingly. Population recovery may depend strongly on colonization capabilities of the affected species. The giant barrel sponge Xestospongia muta is a dominant reef constituent in the Caribbean. However, little is known about its population structure and gene flow. The 5'-end fragment of the mitochondrial gene cytochrome oxidase subunit I is often used to address these kinds of questions, but it presents very low intraspecific nucleotide variability in sponges. In this study, the usefulness of the I3-M11 partition of COI to determine the genetic structure of X. muta was tested for seven populations from Florida, the Bahamas and Belize. A total of 116 sequences of 544 bp were obtained for the I3-M11 partition corresponding to four haplotypes. In order to make a comparison with the 5'-end partition, 10 sequences per haplotype were analyzed for this fragment. The 40 resulting sequences were of 569 bp and corresponded to two haplotypes. The nucleotide diversity of the I3-M11 partition (π = 0.00386) was higher than that of the 5'-end partition (π = 0.00058), indicating better resolution at the intraspecific level. Sponges with the most divergent external morphologies (smooth vs. digitate surface) had different haplotypes, while those with the most common external morphology (rough surface) presented a mixture of haplotypes. Pairwise tests for genetic differentiation among geographic locations based on F ST values showed significant genetic divergence between most populations, but this genetic differentiation was not due to isolation by distance. While limited larval dispersal may have led to differentiation among some of the populations, the patterns of genetic structure appear to be most strongly related to patterns of ocean currents. Therefore, hydrological features may play a major role in sponge colonization and need to be considered in future plans for management and

The double pedigree: a method for studying culturally and genetically inherited behavior in tandem.

Directory of Open Access Journals (Sweden)

Etienne Danchin

Full Text Available Transgenerational sources of biological variation have been at the center of evolutionary studies ever since Darwin and Wallace identified natural selection. This is because evolution can only operate on traits whose variation is transmitted, i.e. traits that are heritable. The discovery of genetic inheritance has led to a semantic shift, resulting in the tendency to consider that only genes are inherited across generations. Today, however, concepts of heredity are being broadened again to integrate the accruing evidence of non-genetic inheritance, and many evolutionary biologists are calling for the inclusion of non-genetic inheritance into an inclusive evolutionary synthesis. Here, we focus on social heredity and its role in the inheritance of behavioral traits. We discuss quantitative genetics methods that might allow us to disentangle genetic and non-genetic transmission in natural populations with known pedigrees. We then propose an experimental design based on cross-fostering among animal cultures, environments and families that has the potential to partition inherited phenotypic variation into socially (i.e. culturally and genetically inherited components. This approach builds towards a new conceptual framework based on the use of an extended version of the animal model of quantitative genetics to integrate genetic and cultural components of behavioral inheritance.

[The discussion of the infiltrative model of mathematical knowledge to genetics teaching].

Science.gov (United States)

Liu, Jun; Luo, Pei-Gao

2011-11-01

Genetics, the core course of biological field, is an importance major-basic course in curriculum of many majors related with biology. Due to strong theoretical and practical as well as abstract of genetics, it is too difficult to study on genetics for many students. At the same time, mathematics is one of the basic courses in curriculum of the major related natural science, which has close relationship with the establishment, development and modification of genetics. In this paper, to establish the intrinsic logistic relationship and construct the integral knowledge network and to help students improving the analytic, comprehensive and logistic abilities, we applied some mathematical infiltrative model genetic knowledge in genetics teaching, which could help students more deeply learn and understand genetic knowledge.

An Improved Car-Following Model Accounting for Impact of Strong Wind

Directory of Open Access Journals (Sweden)

Dawei Liu

2017-01-01

Full Text Available In order to investigate the effect of strong wind on dynamic characteristic of traffic flow, an improved car-following model based on the full velocity difference model is developed in this paper. Wind force is introduced as the influence factor of car-following behavior. Among three components of wind force, lift force and side force are taken into account. The linear stability analysis is carried out and the stability condition of the newly developed model is derived. Numerical analysis is made to explore the effect of strong wind on spatial-time evolution of a small perturbation. The results show that the strong wind can significantly affect the stability of traffic flow. Driving safety in strong wind is also studied by comparing the lateral force under different wind speeds with the side friction of vehicles. Finally, the fuel consumption of vehicle in strong wind condition is explored and the results show that the fuel consumption decreased with the increase of wind speed.

Morphological classification of genetic diversity in cultivated okra ...

African Journals Online (AJOL)

Morphological classification of genetic diversity in cultivated okra, Abelmoschus esculentus (L) Moench using principal component analysis (PCA) and single linkage cluster analysis (SLCA). CC Nwangburuka, OB Kehinde, DK Ojo, OA Denton, AR Popoola ...

Genetics of regular exercise and sedentary behaviors.

Science.gov (United States)

de Geus, Eco J C; Bartels, Meike; Kaprio, Jaakko; Lightfoot, J Timothy; Thomis, Martine

2014-08-01

Studies on the determinants of physical activity have traditionally focused on social factors and environmental barriers, but recent research has shown the additional importance of biological factors, including genetic variation. Here we review the major tenets of this research to arrive at three major conclusions: First, individual differences in physical activity traits are significantly influenced by genetic factors, but genetic contribution varies strongly over age, with heritability of leisure time exercise behavior ranging from 27% to 84% and heritability of sedentary behaviors ranging from 9% to 48%. Second, candidate gene approaches based on animal or human QTLs or on biological relevance (e.g., dopaminergic or cannabinoid activity in the brain, or exercise performance influencing muscle physiology) have not yet yielded the necessary evidence to specify the genetic mechanisms underlying the heritability of physical activity traits. Third, there is significant genetic modulation of the beneficial effects of daily physical activity patterns on strength and endurance improvements and on health-related parameters like body mass index. Further increases in our understanding of the genetic determinants of sedentary and exercise behaviors as well as the genetic modulation of their effects on fitness and health will be key to meaningful future intervention on these behaviors.

Common Genetic Variants Found in HLA and KIR Immune Genes in Autism Spectrum Disorder

OpenAIRE

Torres, Anthony R.; Sweeten, Thayne L.; Johnson, Randall C.; Odell, Dennis; Westover, Jonna B.; Bray-Ward, Patricia; Ward, David C.; Davies, Christopher J.; Thomas, Aaron J.; Croen, Lisa A.; Benson, Michael

2016-01-01

The common variant - common disease hypothesis was proposed to explain diseases with strong inheritance. This model suggests that a genetic disease is the result of the combination of several common genetic variants. Common genetic variants are described as a 5% frequency differential between diseased versus matched control populations. This theory was recently supported by an epidemiology paper stating that about 50% of genetic risk for autism resides in common variants. However, rare va...

The effect of strong intermolecular and chemical interactions on the compatibility of polymers

International Nuclear Information System (INIS)

Askadskii, Andrei A

1999-01-01

The data on compatibility and on the properties of polymer blends are generalised. The emphasis is placed on the formation of strong intermolecular interactions (dipole-dipole interaction and hydrogen bonding) between the components of blends, as well as on the chemical reactions between them. A criterion for the prediction of compatibility of polymers is described in detail. Different cases of compatibility are considered and the dependences of the glass transition temperatures on the composition of blends are analysed. The published data on the effect of strong intermolecular interactions between the blend components on the glass transition temperature are considered. The preparation of interpolymers is described whose macromolecules are composed of incompatible polymers, which leads to the so-called 'forced compatibility.' The bibliography includes 80 references.

Comparative analysis of genetic diversity and differentiation of cauliflower (Brassica oleracea var. botrytis) accessions from two ex situ genebanks.

Science.gov (United States)

Yousef, Eltohamy A A; Müller, Thomas; Börner, Andreas; Schmid, Karl J

2018-01-01

Cauliflower (Brassica oleracea var. botrytis) is an important vegetable crop for human nutrition. We characterized 192 cauliflower accessions from the USDA and IPK genebanks with genotyping by sequencing (GBS). They originated from 26 different countries and represent about 44% of all cauliflower accessions in both genebanks. The analysis of genetic diversity revealed that accessions formed two major groups that represented the two genebanks and were not related to the country of origin. This differentiation was robust with respect to the analysis methods that included principal component analysis, ADMIXTURE and neighbor-joining trees. Genetic diversity was higher in the USDA collection and significant phenotypic differences between the two genebanks were found in three out of six traits investigated. GBS data have a high proportion of missing data, but we observed that the exclusion of single nucleotide polymorphisms (SNPs) with missing data or the imputation of missing SNP alleles produced very similar results. The results indicate that the composition and type of accessions have a strong effect on the structure of genetic diversity of ex situ collections, although regeneration procedures and local adaptation to regeneration conditions may also contribute to a divergence. Fst-based outlier tests of genetic differentiation identified only a small proportion (cauliflower genebank material and our results suggest that it may be useful to incorporate routine genotyping into accession management and seed regeneration to monitor the diversity present in ex situ collections and to reduce the loss of genetic diversity during seed regeneration.

The Status of Genetics Curriculum in Higher Education in the United States: Goals and Assessment

Science.gov (United States)

McElhinny, Teresa L.; Dougherty, Michael J.; Bowling, Bethany V.; Libarkin, Julie C.

2014-01-01

We review the state of genetics instruction in the United States through the lens of backward design, with particular attention to the goals and assessments that inform curricular practice. An analysis of syllabi and leading textbooks indicates that genetics instruction focuses most strongly on foundations of DNA and Mendelian genetics. At the…

Series Hybrid Electric Vehicle Power System Optimization Based on Genetic Algorithm

Science.gov (United States)

Zhu, Tianjun; Li, Bin; Zong, Changfu; Wu, Yang

2017-09-01

Hybrid electric vehicles (HEV), compared with conventional vehicles, have complex structures and more component parameters. If variables optimization designs are carried on all these parameters, it will increase the difficulty and the convergence of algorithm program, so this paper chooses the parameters which has a major influence on the vehicle fuel consumption to make it all work at maximum efficiency. First, HEV powertrain components modelling are built. Second, taking a tandem hybrid structure as an example, genetic algorithm is used in this paper to optimize fuel consumption and emissions. Simulation results in ADVISOR verify the feasibility of the proposed genetic optimization algorithm.

Molecular Genetic of Atopic dermatitis: An Update

Science.gov (United States)

Al-Shobaili, Hani A.; Ahmed, Ahmed A.; Alnomair, Naief; Alobead, Zeiad Abdulaziz; Rasheed, Zafar

2016-01-01

Atopic dermatitis (AD) is a chronic multifactorial inflammatory skin disease. The pathogenesis of AD remains unclear, but the disease results from dysfunctions of skin barrier and immune response, where both genetic and environmental factors play a key role. Recent studies demonstrate the substantial evidences that show a strong genetic association with AD. As for example, AD patients have a positive family history and have a concordance rate in twins. Moreover, several candidate genes have now been suspected that play a central role in the genetic background of AD. In last decade advanced procedures similar to genome-wide association (GWA) and single nucleotide polymorphism (SNP) have been applied on different population and now it has been clarified that AD is significantly associated with genes of innate/adaptive immune systems, human leukocyte antigens (HLA), cytokines, chemokines, drug-metabolizing genes or various other genes. In this review, we will highlight the recent advancements in the molecular genetics of AD, especially on possible functional relevance of genetic variants discovered to date. PMID:27004062

Pronounced fixation, strong population differentiation and complex population history in the Canary Islands blue tit subspecies complex.

Science.gov (United States)

Hansson, Bengt; Ljungqvist, Marcus; Illera, Juan-Carlos; Kvist, Laura

2014-01-01

Evolutionary molecular studies of island radiations may lead to insights in the role of vicariance, founder events, population size and drift in the processes of population differentiation. We evaluate the degree of population genetic differentiation and fixation of the Canary Islands blue tit subspecies complex using microsatellite markers and aim to get insights in the population history using coalescence based methods. The Canary Island populations were strongly genetically differentiated and had reduced diversity with pronounced fixation including many private alleles. In population structure models, the relationship between the central island populations (La Gomera, Tenerife and Gran Canaria) and El Hierro was difficult to disentangle whereas the two European populations showed consistent clustering, the two eastern islands (Fuerteventura and Lanzarote) and Morocco weak clustering, and La Palma a consistent unique lineage. Coalescence based models suggested that the European mainland forms an outgroup to the Afrocanarian population, a split between the western island group (La Palma and El Hierro) and the central island group, and recent splits between the three central islands, and between the two eastern islands and Morocco, respectively. It is clear that strong genetic drift and low level of concurrent gene flow among populations have shaped complex allelic patterns of fixation and skewed frequencies over the archipelago. However, understanding the population history remains challenging; in particular, the pattern of extreme divergence with low genetic diversity and yet unique genetic material in the Canary Island system requires an explanation. A potential scenario is population contractions of a historically large and genetically variable Afrocanarian population, with vicariance and drift following in the wake. The suggestion from sequence-based analyses of a Pleistocene extinction of a substantial part of North Africa and a Pleistocene/Holocene eastward

Pronounced fixation, strong population differentiation and complex population history in the Canary Islands blue tit subspecies complex.

Directory of Open Access Journals (Sweden)

Bengt Hansson

Full Text Available Evolutionary molecular studies of island radiations may lead to insights in the role of vicariance, founder events, population size and drift in the processes of population differentiation. We evaluate the degree of population genetic differentiation and fixation of the Canary Islands blue tit subspecies complex using microsatellite markers and aim to get insights in the population history using coalescence based methods. The Canary Island populations were strongly genetically differentiated and had reduced diversity with pronounced fixation including many private alleles. In population structure models, the relationship between the central island populations (La Gomera, Tenerife and Gran Canaria and El Hierro was difficult to disentangle whereas the two European populations showed consistent clustering, the two eastern islands (Fuerteventura and Lanzarote and Morocco weak clustering, and La Palma a consistent unique lineage. Coalescence based models suggested that the European mainland forms an outgroup to the Afrocanarian population, a split between the western island group (La Palma and El Hierro and the central island group, and recent splits between the three central islands, and between the two eastern islands and Morocco, respectively. It is clear that strong genetic drift and low level of concurrent gene flow among populations have shaped complex allelic patterns of fixation and skewed frequencies over the archipelago. However, understanding the population history remains challenging; in particular, the pattern of extreme divergence with low genetic diversity and yet unique genetic material in the Canary Island system requires an explanation. A potential scenario is population contractions of a historically large and genetically variable Afrocanarian population, with vicariance and drift following in the wake. The suggestion from sequence-based analyses of a Pleistocene extinction of a substantial part of North Africa and a Pleistocene

Genetically meaningful phenotypic subgroups in autism spectrum disorders.

Science.gov (United States)

Veatch, O J; Veenstra-Vanderweele, J; Potter, M; Pericak-Vance, M A; Haines, J L

2014-03-01

Autism spectrum disorder (ASD) is a complex neurodevelopmental disorder with strong evidence for genetic susceptibility. However, the effect sizes for implicated chromosomal loci are small, hard to replicate and current evidence does not explain the majority of the estimated heritability. Phenotypic heterogeneity could be one phenomenon complicating identification of genetic factors. We used data from the Autism Diagnostic Interview-Revised, Autism Diagnostic Observation Schedule, Vineland Adaptive Behavior Scales, head circumferences, and ages at exams as classifying variables to identify more clinically similar subgroups of individuals with ASD. We identified two distinct subgroups of cases within the Autism Genetic Resource Exchange dataset, primarily defined by the overall severity of evaluated traits. In addition, there was significant familial clustering within subgroups (odds ratio, OR ≈ 1.38-1.42, P definition that should increase power to detect genetic factors influencing risk for ASD. © 2013 John Wiley & Sons Ltd and International Behavioural and Neural Genetics Society.

Genetic, Maternal, and Environmental Risk Factors for Cryptorchidism

DEFF Research Database (Denmark)

Barthold, Julia Spencer; Reinhardt, Susanne; Thorup, Jorgen

2016-01-01

genetic risk, multiple susceptibility loci, and a role for the maternal environment. Epidemiologic studies have identified low birth weight or intrauterine growth retardation as factors most strongly associated with cryptorchidism, with additional evidence suggesting that maternal smoking and gestational...

Guidelines for collecting and maintaining archives for genetic monitoring

Science.gov (United States)

Jackson, Jennifer A.; Laikre, Linda; Baker, C. Scott; Kendall, Katherine C.; ,

2012-01-01

Rapid advances in molecular genetic techniques and the statistical analysis of genetic data have revolutionized the way that populations of animals, plants and microorganisms can be monitored. Genetic monitoring is the practice of using molecular genetic markers to track changes in the abundance, diversity or distribution of populations, species or ecosystems over time, and to follow adaptive and non-adaptive genetic responses to changing external conditions. In recent years, genetic monitoring has become a valuable tool in conservation management of biological diversity and ecological analysis, helping to illuminate and define cryptic and poorly understood species and populations. Many of the detected biodiversity declines, changes in distribution and hybridization events have helped to drive changes in policy and management. Because a time series of samples is necessary to detect trends of change in genetic diversity and species composition, archiving is a critical component of genetic monitoring. Here we discuss the collection, development, maintenance, and use of archives for genetic monitoring. This includes an overview of the genetic markers that facilitate effective monitoring, describes how tissue and DNA can be stored, and provides guidelines for proper practice.

Genetic risk variants for dyslexia on chromosome 18 in a German cohort.

Science.gov (United States)

Mueller, B; Ahnert, P; Burkhardt, J; Brauer, J; Czepezauer, I; Quente, E; Boltze, J; Wilcke, A; Kirsten, H

2014-03-01

Dyslexia is characterized by impaired reading and spelling. The disorder has a prevalence of about 5% in Germany, and a strong hereditary component. Several loci are thought to be involved in the development of dyslexia. Scerri et al. identified eight potential dyslexia-associated single nucleotide polymorphisms (SNPs) in seven genes on chromosome 18 in an English-speaking population. Here, we present an association analysis that explores the relevance of these SNPs in a German population comprising 388 dyslexia cases and 364 control cases. In case-control analysis, three nominal SNP associations were replicated. The major alleles of NEDD4L-rs12606138 and NEDD4L-rs8094327 were risk associated [odds ratio (OR) = 1.35, 95% confidence interval (CI) = 1.0-1.7, P-value = 0.017 and OR = 1.39, 95% CI = 1.1-1.7, P-value = 0.007, respectively], and both SNPs were in strong linkage disequilibrium (r(2)  = 0.95). For MYO5B-rs555879, the minor allele was risk associated (OR = 1.31, 95% CI = 1.1-1.6, P-value = 0.011). The combined analysis of SNP sets using set enrichment analysis revealed a study-wide significant association for three SNPs with susceptibility for dyslexia. In summary, our results substantiate genetic markers in NEDD4L and MYO5B as risk factors for dyslexia and provide first evidence that the relevance of these markers is not restricted to the English language. © 2013 John Wiley & Sons Ltd and International Behavioural and Neural Genetics Society.

The major genetic determinants of HIV-1 control affect HLA class I peptide presentation

NARCIS (Netherlands)

Pereyra, Florencia; Jia, Xiaoming; McLaren, Paul J.; Telenti, Amalio; de Bakker, Paul I. W.; Walker, Bruce D.; Ripke, Stephan; Brumme, Chanson J.; Pulit, Sara L.; Carrington, Mary; Kadie, Carl M.; Carlson, Jonathan M.; Heckerman, David; Graham, Robert R.; Plenge, Robert M.; Deeks, Steven G.; Gianniny, Lauren; Crawford, Gabriel; Sullivan, Jordan; Gonzalez, Elena; Davies, Leela; Camargo, Amy; Moore, Jamie M.; Beattie, Nicole; Gupta, Supriya; Crenshaw, Andrew; Burtt, Noël P.; Guiducci, Candace; Gupta, Namrata; Gao, Xiaojiang; Qi, Ying; Yuki, Yuko; Piechocka-Trocha, Alicja; Cutrell, Emily; Rosenberg, Rachel; Moss, Kristin L.; Lemay, Paul; O'Leary, Jessica; Schaefer, Todd; Verma, Pranshu; Toth, Ildiko; Block, Brian; Baker, Brett; Rothchild, Alissa; Lian, Jeffrey; Proudfoot, Jacqueline; Alvino, Donna Marie L.; Vine, Seanna; Addo, Marylyn M.; Allen, Todd M.; Altfeld, Marcus; Henn, Matthew R.; Le Gall, Sylvie; Streeck, Hendrik; Haas, David W.; Kuritzkes, Daniel R.; Robbins, Gregory K.; Shafer, Robert W.; Gulick, Roy M.; Shikuma, Cecilia M.; Haubrich, Richard; Riddler, Sharon; Sax, Paul E.; Daar, Eric S.; Ribaudo, Heather J.; Agan, Brian; Agarwal, Shanu; Ahern, Richard L.; Allen, Brady L.; Altidor, Sherly; Altschuler, Eric L.; Ambardar, Sujata; Anastos, Kathryn; Anderson, Ben; Anderson, Val; Andrady, Ushan; Antoniskis, Diana; Bangsberg, David; Barbaro, Daniel; Barrie, William; Bartczak, J.; Barton, Simon; Basden, Patricia; Basgoz, Nesli; Bazner, Suzane; Bellos, Nicholaos C.; Benson, Anne M.; Berger, Judith; Bernard, Nicole F.; Bernard, Annette M.; Birch, Christopher; Bodner, Stanley J.; Bolan, Robert K.; Boudreaux, Emilie T.; Bradley, Meg; Braun, James F.; Brndjar, Jon E.; Brown, Stephen J.; Brown, Katherine; Brown, Sheldon T.; Burack, Jedidiah; Bush, Larry M.; Cafaro, Virginia; Campbell, Omobolaji; Campbell, John; Carlson, Robert H.; Carmichael, J. Kevin; Casey, Kathleen K.; Cavacuiti, Chris; Celestin, Gregory; Chambers, Steven T.; Chez, Nancy; Chirch, Lisa M.; Cimoch, Paul J.; Cohen, Daniel; Cohn, Lillian E.; Conway, Brian; Cooper, David A.; Cornelson, Brian; Cox, David T.; Cristofano, Michael V.; Cuchural, George; Czartoski, Julie L.; Dahman, Joseph M.; Daly, Jennifer S.; Davis, Benjamin T.; Davis, Kristine; Davod, Sheila M.; DeJesus, Edwin; Dietz, Craig A.; Dunham, Eleanor; Dunn, Michael E.; Ellerin, Todd B.; Eron, Joseph J.; Fangman, John J. W.; Farel, Claire E.; Ferlazzo, Helen; Fidler, Sarah; Fleenor-Ford, Anita; Frankel, Renee; Freedberg, Kenneth A.; French, Neel K.; Fuchs, Jonathan D.; Fuller, Jon D.; Gaberman, Jonna; Gallant, Joel E.; Gandhi, Rajesh T.; Garcia, Efrain; Garmon, Donald; Gathe, Joseph C.; Gaultier, Cyril R.; Gebre, Wondwoosen; Gilman, Frank D.; Gilson, Ian; Goepfert, Paul A.; Gottlieb, Michael S.; Goulston, Claudia; Groger, Richard K.; Gurley, T. Douglas; Haber, Stuart; Hardwicke, Robin; Hardy, W. David; Harrigan, P. Richard; Hawkins, Trevor N.; Heath, Sonya; Hecht, Frederick M.; Henry, W. Keith; Hladek, Melissa; Hoffman, Robert P.; Horton, James M.; Hsu, Ricky K.; Huhn, Gregory D.; Hunt, Peter; Hupert, Mark J.; Illeman, Mark L.; Jaeger, Hans; Jellinger, Robert M.; John, Mina; Johnson, Jennifer A.; Johnson, Kristin L.; Johnson, Heather; Johnson, Kay; Joly, Jennifer; Jordan, Wilbert C.; Kauffman, Carol A.; Khanlou, Homayoon; Killian, Robert K.; Kim, Arthur Y.; Kim, David D.; Kinder, Clifford A.; Kirchner, Jeffrey T.; Kogelman, Laura; Kojic, Erna Milunka; Korthuis, P. Todd; Kurisu, Wayne; Kwon, Douglas S.; LaMar, Melissa; Lampiris, Harry; Lanzafame, Massimiliano; Lederman, Michael M.; Lee, David M.; Lee, Jean M. L.; Lee, Marah J.; Lee, Edward T. Y.; Lemoine, Janice; Levy, Jay A.; Llibre, Josep M.; Liguori, Michael A.; Little, Susan J.; Liu, Anne Y.; Lopez, Alvaro J.; Loutfy, Mono R.; Loy, Dawn; Mohammed, Debbie Y.; Man, Alan; Mansour, Michael K.; Marconi, Vincent C.; Markowitz, Martin; Marques, Rui; Martin, Jeffrey N.; Martin, Harold L.; Mayer, Kenneth Hugh; McElrath, M. Juliana; McGhee, Theresa A.; McGovern, Barbara H.; McGowan, Katherine; McIntyre, Dawn; Mcleod, Gavin X.; Menezes, Prema; Mesa, Greg; Metroka, Craig E.; Meyer-Olson, Dirk; Miller, Andy O.; Montgomery, Kate; Mounzer, Karam C.; Nagami, Ellen H.; Nagin, Iris; Nahass, Ronald G.; Nelson, Margret O.; Nielsen, Craig; Norene, David L.; O'Connor, David H.; Ojikutu, Bisola O.; Okulicz, Jason; Oladehin, Olakunle O.; Oldfield, Edward C.; Olender, Susan A.; Ostrowski, Mario; Owen, William F.; Pae, Eunice; Parsonnet, Jeffrey; Pavlatos, Andrew M.; Perlmutter, Aaron M.; Pierce, Michael N.; Pincus, Jonathan M.; Pisani, Leandro; Price, Lawrence Jay; Proia, Laurie; Prokesch, Richard C.; Pujet, Heather Calderon; Ramgopal, Moti; Rathod, Almas; Rausch, Michael; Ravishankar, J.; Rhame, Frank S.; Richards, Constance Shamuyarira; Richman, Douglas D.; Rodes, Berta; Rodriguez, Milagros; Rose, Richard C.; Rosenberg, Eric S.; Rosenthal, Daniel; Ross, Polly E.; Rubin, David S.; Rumbaugh, Elease; Saenz, Luis; Salvaggio, Michelle R.; Sanchez, William C.; Sanjana, Veeraf M.; Santiago, Steven; Schmidt, Wolfgang; Schuitemaker, Hanneke; Sestak, Philip M.; Shalit, Peter; Shay, William; Shirvani, Vivian N.; Silebi, Vanessa I.; Sizemore, James M.; Skolnik, Paul R.; Sokol-Anderson, Marcia; Sosman, James M.; Stabile, Paul; Stapleton, Jack T.; Starrett, Sheree; Stein, Francine; Stellbrink, Hans-Jurgen; Sterman, F. Lisa; Stone, Valerie E.; Stone, David R.; Tambussi, Giuseppe; Taplitz, Randy A.; Tedaldi, Ellen M.; Theisen, William; Torres, Richard; Tosiello, Lorraine; Tremblay, Cecile; Tribble, Marc A.; Trinh, Phuong D.; Tsao, Alice; Ueda, Peggy; Vaccaro, Anthony; Valadas, Emilia; Vanig, Thanes J.; Vecino, Isabel; Vega, Vilma M.; Veikley, Wenoah; Wade, Barbara H.; Walworth, Charles; Wanidworanun, Chingchai; Ward, Douglas J.; Warner, Daniel A.; Weber, Robert D.; Webster, Duncan; Weis, Steve; Wheeler, David A.; White, David J.; Wilkins, Ed; Winston, Alan; Wlodaver, Clifford G.; van't Wout, Angelique; Wright, David P.; Yang, Otto O.; Yurdin, David L.; Zabukovic, Brandon W.; Zachary, Kimon C.; Zeeman, Beth; Zhao, Meng

2010-01-01

Infectious and inflammatory diseases have repeatedly shown strong genetic associations within the major histocompatibility complex (MHC); however, the basis for these associations remains elusive. To define host genetic effects on the outcome of a chronic viral infection, we performed genome-wide

Measurement of strong interaction parameters in antiprotonic hydrogen and deuterium

CERN Document Server

Augsburger, M A; Borchert, G L; Chatellard, D; Egger, J P; El-Khoury, P; Gorke, H; Gotta, D; Hauser, P R; Indelicato, P J; Kirch, K; Lenz, S; Siems, T; Simons, L M

1999-01-01

In the PS207 experiment at CERN, X-rays from antiprotonic hydrogen and deuterium have been measured at low pressure. The strong interaction shift and the broadening of the K/sub alpha / transition in antiprotonic hydrogen were $9 determined. Evidence was found for the individual hyperfine components of the protonium ground state. (7 refs).

Company Slogan and a Vivid Image of a Trademark - as Main Components of a Strong Brand

Directory of Open Access Journals (Sweden)

Igor BELOSTECINIC

2015-12-01

Full Text Available Among other methods, good brand managers always affect clients and strengthen their fidelity to the brand by means of company advertising slogans and vivid images associated with this brand. Slogans may function as useful “levers” or “hooks” helping clients to understand the essence of a trademark and its peculiarity, as well as to nail in clients' minds the established image of a strong brand. One of the “hooks” attracting attention to brand and helping to nail it in a common man's mind – is a company (advertising slogan - short message or motto, which actively presents the key theme of the brand in general or of a certain advertising campaign, and contains substantial information, reflecting the essence of campaign's or product's marketing offer. One must admit that it is nice to recall favorite philosopher's aphorisms or sayings while getting up in the morning, and to whistle an aria from a renowned opera on your way to work. However, more often people sing unsophisticated verses about the “sign of a good taste” and get annoyed by a trivial call to “have a break” going round in their heads. This means that the advertisement of popular chocolate bars and drinks has hit its target. The main lever for success in generation of a positive and recognizable brand image - is the slogan and its graphic image in consumer's mind. Together with other brand components (logo, corporate colors, sound or music image a slogan generates the system of constant elements which ensure the brand's internal unity and are aimed at creation of exposure effect. To some extent, we all are “ad eaters” and are always capable of estimating an ad, even if it is at the level of feelings: whether we like it or not. So why a certain advertisement can make us smile, elicit good feelings and cause an urge to buy product/service that is being advertised, and another one - evokes disappointment and annoyance? The answer is obvious: the first one was

[MapDraw: a microsoft excel macro for drawing genetic linkage maps based on given genetic linkage data].

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Liu, Ren-Hu; Meng, Jin-Ling

2003-05-01

MAPMAKER is one of the most widely used computer software package for constructing genetic linkage maps.However, the PC version, MAPMAKER 3.0 for PC, could not draw the genetic linkage maps that its Macintosh version, MAPMAKER 3.0 for Macintosh,was able to do. Especially in recent years, Macintosh computer is much less popular than PC. Most of the geneticists use PC to analyze their genetic linkage data. So a new computer software to draw the same genetic linkage maps on PC as the MAPMAKER for Macintosh to do on Macintosh has been crying for. Microsoft Excel,one component of Microsoft Office package, is one of the most popular software in laboratory data processing. Microsoft Visual Basic for Applications (VBA) is one of the most powerful functions of Microsoft Excel. Using this program language, we can take creative control of Excel, including genetic linkage map construction, automatic data processing and more. In this paper, a Microsoft Excel macro called MapDraw is constructed to draw genetic linkage maps on PC computer based on given genetic linkage data. Use this software,you can freely construct beautiful genetic linkage map in Excel and freely edit and copy it to Word or other application. This software is just an Excel format file. You can freely copy it from ftp://211.69.140.177 or ftp://brassica.hzau.edu.cn and the source code can be found in Excel's Visual Basic Editor.

Spectral contents of electron waves under strong Langmuir turbulence

Energy Technology Data Exchange (ETDEWEB)

Alves, Maria Virginia; Dallaqua, Renato Sergio [Instituto Nacional de Pesquisas Espaciais (INPE), Sao Jose dos Campos, SP (Brazil); Prado, Fabio do [Centro Universitario UNIFEI, Itajuba, MG (Brazil); Karfidov, Dmitry Mikhailovich [General Physics Inst., Moscow (Russian Federation)

2003-07-01

Experimental results of electron plasma waves excited in a beam plasma system are presented. Based on our experimental results we determine the transition from the quasi-linear to non-linear regime. We present the space evolution of the electron beam distribution function for both regimes. The spectrum of the electron plasma wave in the non-linear regime shows a component with frequency larger than the plasma frequency besides the plasma frequency itself. We show that the higher frequency component is strongly affected by Landau damping, indicating a dissipation region. The measured experimental power spectrum of this wave shows a dependence on wave number k given by W{sub k} {proportional_to} k{sup -7/2} as theoretically predicted. (author)

Low interbasin connectivity in a facultatively diadromous fish: evidence from genetics and otolith chemistry.

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Hughes, Jane M; Schmidt, Daniel J; Macdonald, Jed I; Huey, Joel A; Crook, David A

2014-03-01

Southern smelts (Retropinna spp.) in coastal rivers of Australia are facultatively diadromous, with populations potentially containing individuals with diadromous or wholly freshwater life histories. The presence of diadromous individuals is expected to reduce genetic structuring between river basins due to larval dispersal via the sea. We use otolith chemistry to distinguish between diadromous and nondiadromous life histories and population genetics to examine interbasin connectivity resulting from diadromy. Otolith strontium isotope ((87) Sr:(86) Sr) transects identified three main life history patterns: amphidromy, freshwater residency and estuarine/marine residency. Despite the potential for interbasin connectivity via larval mixing in the marine environment, we found unprecedented levels of genetic structure for an amphidromous species. Strong hierarchical structure along putative taxonomic boundaries was detected, along with highly structured populations within groups using microsatellites (FST  = 0.046-0.181), and mtDNA (ΦST  = 0.498-0.816). The presence of strong genetic subdivision, despite the fact that many individuals reside in saline water during their early life history, appears incongruous. However, analysis of multielemental signatures in the otolith cores of diadromous fish revealed strong discrimination between river basins, suggesting that diadromous fish spend their early lives within chemically distinct estuaries rather than the more homogenous marine environment, thus avoiding dispersal and maintaining genetic structure. © 2014 John Wiley & Sons Ltd.

Effective potential kinetic theory for strongly coupled plasmas

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Baalrud, Scott D.; Daligault, Jérôme

2016-11-01

The effective potential theory (EPT) is a recently proposed method for extending traditional plasma kinetic and transport theory into the strongly coupled regime. Validation from experiments and molecular dynamics simulations have shown it to be accurate up to the onset of liquid-like correlation parameters (corresponding to Γ ≃ 10-50 for the one-component plasma, depending on the process of interest). Here, this theory is briefly reviewed along with comparisons between the theory and molecular dynamics simulations for self-diffusivity and viscosity of the one-component plasma. A number of new results are also provided, including calculations of friction coefficients, energy exchange rates, stopping power, and mobility. The theory is also cast in the Landau and Fokker-Planck kinetic forms, which may prove useful for enabling efficient kinetic computations.

Extension of lattice cluster theory to strongly interacting, self-assembling polymeric systems.

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Freed, Karl F

2009-02-14

A new extension of the lattice cluster theory is developed to describe the influence of monomer structure and local correlations on the free energy of strongly interacting and self-assembling polymer systems. This extension combines a systematic high dimension (1/d) and high temperature expansion (that is appropriate for weakly interacting systems) with a direct treatment of strong interactions. The general theory is illustrated for a binary polymer blend whose two components contain "sticky" donor and acceptor groups, respectively. The free energy is determined as an explicit function of the donor-acceptor contact probabilities that depend, in turn, on the local structure and both the strong and weak interactions.

Short-term alteration of biotic and abiotic components of the pelagic system in a shallow bay produced by a strong natural hypoxia event

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Veas, Rodrigo; Anabalón, Valeria; Quiñones, Renato A.

2017-01-01

In January 2008 there was an intensive and extensive upwelling event in the southern Humboldt Current System. This event produced an intrusion of water with low dissolved oxygen into Coliumo Bay, which caused massive mortality and the beaching of pelagic and benthic organisms, including zooplankton. During this event, which lasted 3 to 5 days, we studied and evaluated the effect of the hypoxic water in the bay on the abundance of macrozooplankton, nanoplankton and microphytoplankton, the concentration of several nutrients and hydrographic conditions. At the beginning of the hypoxia event the water column had very low dissolved oxygen concentrations (oxygen minimum zone from the Humboldt Current System. Redox, pH, nitrate, phosphate, silicate and chlorophyll-a values were the lowest, while nitrate and the phaeopigment values were the highest. The N:P ratio was below 16, and the abundance of nano- and microphytoplankton were at their lowest, the latter also with the lowest proportion of live organisms. Macrozooplankton had the greatest abundance during hypoxia, dominated mainly by crustacean, fish eggs and amphipods. The hypoxia event generated a strong short-term alteration of all biotic and abiotic components of the pelagic system in Coliumo Bay and the neighboring coastal zone. These negative effects associated with strong natural hypoxia events could have important consequences for the productivity and ecosystem functioning of the coastal zone of the Humboldt Current System if, as suggested by several models, winds favorable to upwelling should increase due to climate change. The effects of natural hypoxia in this coastal zone can be dramatic especially for pelagic and benthic species not adapted to endure conditions of low dissolved oxygen. PMID:28715447

Equation of state of strongly coupled plasma mixtures

International Nuclear Information System (INIS)

DeWitt, H.E.

1984-01-01

Thermodynamic properties of strongly coupled (high density) plasmas of mixtures of light elements have been obtained by Monte Carlo simulations. For an assumed uniform charge background the equation of state of ionic mixtures is a simple extension of the one-component plasma EOS. More realistic electron screening effects are treated in linear response theory and with an appropriate electron dielectric function. Results have been obtained for the ionic pair distribution functions, and for the electric microfield distribution

The evolution of strong reciprocity: cooperation in heterogeneous populations.

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Bowles, Samuel; Gintis, Herbert

2004-02-01

How do human groups maintain a high level of cooperation despite a low level of genetic relatedness among group members? We suggest that many humans have a predisposition to punish those who violate group-beneficial norms, even when this imposes a fitness cost on the punisher. Such altruistic punishment is widely observed to sustain high levels of cooperation in behavioral experiments and in natural settings. We offer a model of cooperation and punishment that we call STRONG RECIPROCITY: where members of a group benefit from mutual adherence to a social norm, strong reciprocators obey the norm and punish its violators, even though as a result they receive lower payoffs than other group members, such as selfish agents who violate the norm and do not punish, and pure cooperators who adhere to the norm but free-ride by never punishing. Our agent-based simulations show that, under assumptions approximating likely human environments over the 100000 years prior to the domestication of animals and plants, the proliferation of strong reciprocators when initially rare is highly likely, and that substantial frequencies of all three behavioral types can be sustained in a population. As a result, high levels of cooperation are sustained. Our results do not require that group members be related or that group extinctions occur.

A simple algorithm to estimate genetic variance in an animal threshold model using Bayesian inference Genetics Selection Evolution 2010, 42:29

DEFF Research Database (Denmark)

Ødegård, Jørgen; Meuwissen, Theo HE; Heringstad, Bjørg

2010-01-01

Background In the genetic analysis of binary traits with one observation per animal, animal threshold models frequently give biased heritability estimates. In some cases, this problem can be circumvented by fitting sire- or sire-dam models. However, these models are not appropriate in cases where...... records exist for the parents). Furthermore, the new algorithm showed much faster Markov chain mixing properties for genetic parameters (similar to the sire-dam model). Conclusions The new algorithm to estimate genetic parameters via Gibbs sampling solves the bias problems typically occurring in animal...... individual records exist on parents. Therefore, the aim of our study was to develop a new Gibbs sampling algorithm for a proper estimation of genetic (co)variance components within an animal threshold model framework. Methods In the proposed algorithm, individuals are classified as either "informative...

Role of genetics in infection-associated arthritis.

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Benham, Helen; Robinson, Philip C; Baillet, Athan C; Rehaume, Linda M; Thomas, Ranjeny

2015-04-01

Genetic discoveries in arthritis and their associated biological pathways spanning the innate and adaptive immune system demonstrate the strong association between susceptibility to arthritis and control of exogenous organisms. The canonical theory of the aetiology of immune-mediated arthritis and other immune-mediated diseases is that the introduction of exogenous antigenic stimuli to a genetically susceptible host sets up the environment for an abnormal immune response manifesting as disease. A disruption in host-microbe homeostasis driven by disease-associated genetic variants could ultimately provide the source of exogenous antigen triggering disease development. We discuss genetic variants impacting the innate and adaptive arms of the immune system and their relationship to microbial control and arthritic disease. We go on to consider the evidence for a relationship between HLA-B27, infection and arthritis, and then emerging evidence for an interaction between microbiota and rheumatoid arthritis. Copyright © 2015 Elsevier Ltd. All rights reserved.

Genetic exchange versus genetic differentiation in a medium-sized inversion of Drosophila: the A2/Ast arrangements of Drosophila subobscura.

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Nóbrega, Clévio; Khadem, Mahnaz; Aguadé, Montserrat; Segarra, Carmen

2008-08-01

Chromosomal inversion polymorphism affects nucleotide variation at loci associated with inversions. In Drosophila subobscura, a species with a rich chromosomal inversion polymorphism and the largest recombinational map so far reported in the Drosophila genus, extensive genetic structure of nucleotide variation was detected in the segment affected by the O(3) inversion, a moderately sized inversion at Muller's element E. Indeed, a strong genetic differentiation all over O(3) and no evidence of a higher genetic exchange in the center of the inversion than at breakpoints were detected. In order to ascertain, whether other polymorphic and differently sized inversions of D. subobscura also exhibited a strong genetic structure, nucleotide variation in 5 gene regions (P236, P275, P150, Sxl, and P125) located along the A(2) inversion was analyzed in A(st) and A(2) chromosomes of D. subobscura. A(2) is a medium-sized inversion at Muller's element A and forms a single inversion loop in heterokaryotypes. The lower level of variation in A(2) relative to A(st) and the significant excess of low-frequency variants at polymorphic sites indicate that nucleotide variation at A(2) is not at mutation-drift equilibrium. The closest region to an inversion breakpoint, P236, exhibits the highest level of genetic differentiation (F(ST)) and of linkage disequilibrium (LD) between arrangements and variants at nucleotide polymorphic sites. The remaining 4 regions show a higher level of genetic exchange between A(2) and A(st) chromosomes than P236, as revealed by F(ST) and LD estimates. However, significant genetic differentiation between the A(st) and A(2) arrangements was detected not only at P236 but also in the other 4 regions separated from the nearest breakpoint by 1.2-2.9 Mb. Therefore, the extent of genetic exchange between arrangements has not been high enough to homogenize nucleotide variation in the center of the A(2) inversion. A(2) can be considered a typical successful inversion

The Use of Principal Components in Long-Range Forecasting

Science.gov (United States)

Chern, Jonq-Gong

Large-scale modes of the global sea surface temperatures and the Northern Hemisphere tropospheric circulation are described by principal component analysis. The first and the second SST components well describe the El Nino episodes, and the El Nino index (ENI), suggested in this study, is consistent with the winter Southern Oscillation index (SOI), where this ENI is a composite component of the weighted first and second SST components. The large-scale interactive modes of the coupling ocean-atmosphere system are identified by cross-correlation analysis The result shows that the first SST component is strongly correlated with the first component of geopotential height in lead time of 6 months. In the El Nino-Southern Oscillation (ENSO) evolution, the El Nino mode strongly influences the winter tropospheric circulation in the mid -latitudes for up to three leading seasons. The regional long-range variation of climate is investigated with these major components of the SST and the tropospheric circulation. In the mid-latitude, the climate of the central United States shows a weak linkage with these large-scale circulations, and the climate of the western United States appears to be consistently associated with the ENSO modes. These El Nino modes also show a dominant influence on Eastern Asia as evidenced in Taiwan Mei-Yu patterns. Possible regional long-range forecasting schemes, utilizing the complementary characteristics of the winter El Nino mode and SST anomalies, are examined with the Taiwan Mei-Yu.

Genetic determinants of hepatic steatosis in man

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Hooper, Amanda J.; Adams, Leon A.; Burnett, John R.

2011-01-01

Hepatic steatosis is one of the most common liver disorders in the general population. The main cause of hepatic steatosis is nonalcoholic fatty liver disease (NAFLD), representing the hepatic component of the metabolic syndrome, which is characterized by type 2 diabetes, obesity, and dyslipidemia. Insulin resistance and excess adiposity are considered to play key roles in the pathogenesis of NAFLD. Although the risk factors for NAFLD are well established, the genetic basis of hepatic steatosis is largely unknown. Here we review recent progress on genomic variants and their association with hepatic steatosis and discuss the potential impact of these genetic studies on clinical practice. Identifying the genetic determinants of hepatic steatosis will lead to a better understanding of the pathogenesis and progression of NAFLD. PMID:21245030

Family Conflict Interacts with Genetic Liability in Predicting Childhood and Adolescent Depression

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Rice, Frances; Harold, Gordon T.; Shelton, Katherine H.; Thapar, Anita

2006-01-01

Objective: To test for gene-environment interaction with depressive symptoms and family conflict. Specifically, to first examine whether the influence of family conflict in predicting depressive symptoms is increased in individuals at genetic risk of depression. Second, to test whether the genetic component of variance in depressive symptoms…

Genetic educational needs and the role of genetics in primary care: a focus group study with multiple perspectives

Directory of Open Access Journals (Sweden)

van der Vleuten Cees

2011-02-01

Full Text Available Abstract Background Available evidence suggests that improvements in genetics education are needed to prepare primary care providers for the impact of ongoing rapid advances in genomics. Postgraduate (physician training and master (midwifery training programmes in primary care and public health are failing to meet these perceived educational needs. The aim of this study was to explore the role of genetics in primary care (i.e. family medicine and midwifery care and the need for education in this area as perceived by primary care providers, patient advocacy groups and clinical genetics professionals. Methods Forty-four participants took part in three types of focus groups: mono-disciplinary groups of general practitioners and midwives, respectively and multidisciplinary groups composed of a diverse set of experts. The focus group sessions were audio-taped, transcribed verbatim and analysed using content analysis. Recurrent themes were identified. Results Four themes emerged regarding the educational needs and the role of genetics in primary care: (1 genetics knowledge, (2 family history, (3 ethical dilemmas and psychosocial effects in relation to genetics and (4 insight into the organisation and role of clinical genetics services. These themes reflect a shift in the role of genetics in primary care with implications for education. Although all focus group participants acknowledged the importance of genetics education, general practitioners felt this need more urgently than midwives and more strongly emphasized their perceived knowledge deficiencies. Conclusion The responsibilities of primary care providers with regard to genetics require further study. The results of this study will help to develop effective genetics education strategies to improve primary care providers' competencies in this area. More research into the educational priorities in genetics is needed to design courses that are suitable for postgraduate and master programmes for

Genetics of Alcoholism.

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Zhu, Ena C; Soundy, Timothy J; Hu, Yueshan

2017-05-01

Consuming excessive amounts of alcohol has the potential to modify an individual's brain and lead to alcohol dependence. Alcohol use leads to 88,000 deaths every year in the U.S. alone and can lead to other health issues including cancers, such as colorectal cancer, and mental health problems. While drinking behavior varies due to environmental factors, genetic factors also contribute to the risk of alcoholism. Certain genes affecting alcohol metabolism and neurotransmitters have been found to contribute to or inhibit the risk. Geneenvironment interactions may also play a role in the susceptibility of alcoholism. With a better understanding of the different components that can contribute to alcoholism, more personalized treatment could cater to the individual. This review discusses the major genetic factors and some small variants in other genes that contribute to alcoholism, as well as considers the gene-environmental interactions. Copyright© South Dakota State Medical Association.

Detecting Genomic Signatures of Natural Selection with Principal Component Analysis: Application to the 1000 Genomes Data.

Science.gov (United States)

Duforet-Frebourg, Nicolas; Luu, Keurcien; Laval, Guillaume; Bazin, Eric; Blum, Michael G B

2016-04-01

To characterize natural selection, various analytical methods for detecting candidate genomic regions have been developed. We propose to perform genome-wide scans of natural selection using principal component analysis (PCA). We show that the common FST index of genetic differentiation between populations can be viewed as the proportion of variance explained by the principal components. Considering the correlations between genetic variants and each principal component provides a conceptual framework to detect genetic variants involved in local adaptation without any prior definition of populations. To validate the PCA-based approach, we consider the 1000 Genomes data (phase 1) considering 850 individuals coming from Africa, Asia, and Europe. The number of genetic variants is of the order of 36 millions obtained with a low-coverage sequencing depth (3×). The correlations between genetic variation and each principal component provide well-known targets for positive selection (EDAR, SLC24A5, SLC45A2, DARC), and also new candidate genes (APPBPP2, TP1A1, RTTN, KCNMA, MYO5C) and noncoding RNAs. In addition to identifying genes involved in biological adaptation, we identify two biological pathways involved in polygenic adaptation that are related to the innate immune system (beta defensins) and to lipid metabolism (fatty acid omega oxidation). An additional analysis of European data shows that a genome scan based on PCA retrieves classical examples of local adaptation even when there are no well-defined populations. PCA-based statistics, implemented in the PCAdapt R package and the PCAdapt fast open-source software, retrieve well-known signals of human adaptation, which is encouraging for future whole-genome sequencing project, especially when defining populations is difficult. © The Author(s) 2015. Published by Oxford University Press on behalf of the Society for Molecular Biology and Evolution.

Analysis of genetic diversity of Tunisian pistachio (Pistacia vera L.) using sequence-related amplified polymorphism (SRAP) markers.

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Guenni, K; Aouadi, M; Chatti, K; Salhi-Hannachi, A

2016-10-17

Sequence-related amplified polymorphism (SRAP) markers preferentially amplify open reading frames and were used to study the genetic diversity of Tunisian pistachio. In the present study, 43 Pistacia vera accessions were screened using seven SRAP primer pairs. A total of 78 markers was revealed (95.12%) with an average polymorphic information content of 0.850. The results suggest that there is strong genetic differentiation, which characterizes the local resources (G ST = 0.307). High gene flow (N m = 1.127) among groups was explained by the exchange of plant material among regions. Analysis of molecular variance revealed significant differences within groups and showed that 73.88% of the total genetic diversity occurred within groups, whereas the remaining 26.12% occurred among groups. Bayesian clustering and principal component analysis identified three pools, El Guettar, Pollenizers, and the rest of the pistachios belonging to the Gabès, Kasserine, and Sfax localities. Bayesian analysis revealed that El Guettar and male genotypes were assigned with more than 80% probability. The BayeScan method proposed that locus 59 (F13-R9) could be used in the development of sex-linked SCAR markers from SRAP since it is a commonly detected locus in comparisons involving the Pollenizers group. This is the first application of SRAP markers for the assessment of genetic diversity in Tunisian germplasm of P. vera. Such information will be useful to define conservation strategies and improvement programs for this species.

Quantifying introgression risk with realistic population genetics

NARCIS (Netherlands)

Ghosh, A.; Meirmans, P.G.; Haccou, P.

2012-01-01

Introgression is the permanent incorporation of genes from the genome of one population into another. This can have severe consequences, such as extinction of endemic species, or the spread of transgenes. Quantification of the risk of introgression is an important component of genetically modified