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Genetic Constitution (genetic + constitution)
Selected AbstractsNew genomic avenues in behavioural neuroendocrinology ,EUROPEAN JOURNAL OF NEUROSCIENCE, Issue 3 2002S. L. Lightman Abstract Neuroendocrine systems play a key role not only in the maintenance of whole-body homeostasis but also as the link between behavioural, endocrine and autonomic responses to environmental stimuli. It is becoming increasingly clear that neuroendocrine regulatory mechanisms are under the control of a combination of factors including genetic background, environment and early-life programming. Patterns of gene expression are increasingly being used to provide information on the genotypes associated with particular behaviours, and modulation of specific parts of the genome allow investigation of the contribution of particular genes. The sequencing of the genome provides a unique opportunity to elucidate the genetic contribution to neuroendocrine and behavioural processes, and to investigate the interactions between genetic and environmental factors. Although drugs can be used to activate or inhibit neurotransmitters and receptors, they lack specificity. New technologies now permit the activation or inactivation of both neurotransmitters and receptors in specific areas of the brain for defined periods, including crucially important developmental windows when activation appears to have long-term consequences. The future challenges are to define the critical mechanisms through which the genetic constitution of an individual human or experimental animal interacts with environmental cues to result in altered physiological or even pathological behaviour and endocrine function. [source] Crystal structures of Nipah and Hendra virus fusion core proteinsFEBS JOURNAL, Issue 19 2006Zhiyong Lou The Nipah and Hendra viruses are highly pathogenic paramyxoviruses that recently emerged from flying foxes to cause serious disease outbreaks in humans and livestock in Australia, Malaysia, Singapore and Bangladesh. Their unique genetic constitution, high virulence and wide host range set them apart from other paramyxoviruses. These characteristics have led to their classification into the new genus Henpavirus within the family Paramyxoviridae and to their designation as Biosafety Level 4 pathogens. The fusion protein, an enveloped glycoprotein essential for viral entry, belongs to the family of class I fusion proteins and is characterized by the presence of two heptad repeat (HR) regions, HR1 and HR2. These two regions associate to form a fusion-active hairpin conformation that juxtaposes the viral and cellular membranes to facilitate membrane fusion and enable subsequent viral entry. The Hendra and Nipah virus fusion core proteins were crystallized and their structures determined to 2.2 Å resolution. The Nipah and Hendra fusion core structures are six-helix bundles with three HR2 helices packed against the hydrophobic grooves on the surface of a central coiled coil formed by three parallel HR1 helices in an oblique antiparallel manner. Because of the high level of conservation in core regions, it is proposed that the Nipah and Hendra virus fusion cores can provide a model for membrane fusion in all paramyxoviruses. The relatively deep grooves on the surface of the central coiled coil represent a good target site for drug discovery strategies aimed at inhibiting viral entry by blocking hairpin formation. [source] Dopamine Receptor D2 Polymorphism Moderates the Effect of Parental Education on Adolescents' School PerformanceMIND, BRAIN, AND EDUCATION, Issue 2 2008Liisa Keltikangas-Järvinen ABSTRACT, High parental socioeconomic status is known to have a positive effect on students' academic achievement. We examined whether variation in the dopamine receptor gene (DRD2 polymorphism, rs 1800497) modifies the association between parental educational level and school performance in adolescence. The participants were a randomly selected subsample of individuals participating in the Cardiovascular Risk in Young Finns study (921 girls and 742 boys) aged 12,15 years at the time school performance was assessed. The genotyping was performed using TaqMan 5,'-nuclease assay. A significant interaction was found between childhood parental educational level and students' DRD2 polymorphism on academic achievement after adjustment for age, gender, household income, parental occupation, maternal nurturance, hyperactivity, and sociability. Parental educational level was significantly positively associated with school achievement in the A2/A2 (n = 1,061) and the A1/A2 (n = 529) genotype groups, but was negative and statistically insignificant in participants carrying the A1/A1 (n = 73) genotype. It is concluded that the extent to which parental education status affects an individual's academic achievement may be dependent on the individual's genetic constitution. The findings may increase an acceptance of genetic influence in education, and, consequently, may increase accurateness of educational interventions. [source] Diversification within glacial refugia: tempo and mode of evolution of the polytypic fish Barbus sclateriMOLECULAR ECOLOGY, Issue 15 2009HUGO F. GANTE Abstract A diversity of evolutionary processes can be responsible for generating and maintaining biodiversity. Molecular markers were used to investigate the influence of Plio-Pleistocene climatic oscillations on the evolutionary history of taxa restricted to the freshwaters of a classical glacial refugium. Population genetic, phylogenetic and phylogeographical methods allowed the inference of temporal dynamics of cladogenesis and processes shaping present-day genetic constitution of Barbus sclateri, a polytypic taxon found in several independent river drainages in southern Iberian Peninsula. Results from different analyses consistently indicate several range expansions, high levels of allopatric fragmentation, and admixture following secondary contacts throughout its evolutionary history. Using a Bayesian demographical coalescent model on mitochondrial DNA sequences calibrated with fossil evidence, all cladogenetic events within B. sclateri are inferred to have occurred during the Pleistocene and were probably driven by environmental factors. Our results suggest that glaciation cycles did not inhibit cladogenesis and probably interacted with regional geomorphology to promote diversification. We conclude that this polytypic taxon is a species complex that recently diversified in allopatry, and that Pleistocene glaciation,deglaciation cycles probably contributed to the generation of biological diversity in a classical glacial refugium with high endemicity. [source] Afro-derived Brazilian populations: Male genetic constitution estimated by Y-chromosomes STRs and AluYAP element polymorphismsAMERICAN JOURNAL OF HUMAN BIOLOGY, Issue 3 2009Guilherme Galvarros Bueno Lobo Ribeiro The genetic constitution of Afro-derived Brazilian populations is barely studied. To improve that knowledge, we investigated the AluYAP element and five Y-chromosome STRs (DYS19, DYS390, DYS391, DYS392, and DYS393) to estimate ethnic male contribution in the constitution of four Brazilian quilombos remnants: Mocambo, Rio das Rãs, Kalunga, and Riacho de Sacutiaba. Results indicated significant differences among communities, corroborating historical information about the Brazilian settlement. We concluded that besides African contribution, there was a great European participation in the constitution of these four populations and that observed haplotype variability could be explained by gene flow to quilombos remnants and mutational events in microsatellites (STRs). Am. J. Hum. Biol., 2009. © 2009 Wiley-Liss, Inc. [source] Grapevine biology and adaptation to viticultureAUSTRALIAN JOURNAL OF GRAPE AND WINE RESEARCH, Issue 2 2000W. JAMES (JIM) HARDIE Abstract This paper provides a context for later papers in these Proceedings on specific aspects of reproductive biology; particularly those aspects that impact on viticulture. In keeping with the concept of ,selfish genes' I posit that grapevine reproductive biology is most usefully introduced in a broad context where particular genotypes within a population are regarded as complex survival machines programmed by their genes to ensure successful cycles of growth and reproductive development. Topics not covered by this symposium such as leaf function, root physiology and nutrition, along with those that are a focus, viz. the physiology of bud fruitfulness, floral anatomy and pericarp development, have all featured in the evolutionary history of Vitis spp. Such adaptive features must be regarded as specialised components of a plant system regulated by a genetic constitution that has successfully evolved over millions of years against unrelenting environmental selection pressures i.e. adaptation by natural selection. Human selection over a subsequent 5000 years or so has added further viticultural refinements to those gene-based adaptive features. [source] ,To prove this is the industry's best hope': big tobacco's support of research on the genetics of nicotine addictionADDICTION, Issue 6 2010Kenneth R. Gundle ABSTRACT Background New molecular techniques focus a genetic lens upon nicotine addiction. Given the medical and economic costs associated with smoking, innovative approaches to smoking cessation and prevention must be pursued; but can sound research be manipulated by the tobacco industry? Methodology The chronological narrative of this paper was created using iterative reviews of primary sources (the Legacy Tobacco Documents), supplemented with secondary literature to provide a broader context. The empirical data inform an ethics and policy analysis of tobacco industry-funded research. Findings The search for a genetic basis for smoking is consistent with industry's decades-long plan to deflect responsibility away from the tobacco companies and onto individuals' genetic constitutions. Internal documents reveal long-standing support for genetic research as a strategy to relieve the tobacco industry of its legal responsibility for tobacco-related disease. Conclusions Industry may turn the findings of genetics to its own ends, changing strategy from creating a ,safe' cigarette to defining a ,safe' smoker. [source] | |||||||||||||