Search results for "population genetic"
showing 10 items of 273 documents
Earliest Evidence for Social Endogamy in the 9,000-Year-Old-Population of Basta, Jordan
2013
The transition from mobile to sedentary life was one of the greatest social challenges of the human past. Yet little is known about the impact of this fundamental change on social interactions amongst early Neolithic communities, which are best recorded in the Near East. The importance of social processes associated with these economic and ecological changes has long been underestimated. However, ethnographic observations demonstrate that generalized reciprocity – such as open access to resources and land – had to be reduced to a circumscribed group before regular farming and herding could be successfully established. Our aim was thus to investigate the role of familial relationships as one…
Common variants of the liver fatty acid binding protein gene influence the risk of type 2 diabetes and insulin resistance in Spanish population.
2012
Journal Article; Research Support, Non-U.S. Gov't; SUMMARY The main objective was to evaluate the association between SNPs and haplotypes of the FABP1-4 genes and type 2 diabetes, as well as its interaction with fat intake, in one general Spanish population. The association was replicated in a second population in which HOMA index was also evaluated. METHODS 1217 unrelated individuals were selected from a population-based study [Hortega study: 605 women; mean age 54 y; 7.8% with type 2 diabetes]. The replication population included 805 subjects from Segovia, a neighboring region of Spain (446 females; mean age 52 y; 10.3% with type 2 diabetes). DM2 mellitus was defined in a similar way in b…
EPHA2 polymorphisms and age-related cataract in India.
2012
Objective: We investigated whether previously reported single nucleotide polymorphisms (SNPs) of EPHA2 in European studies are associated with cataract in India. Methods: We carried out a population-based genetic association study. We enumerated randomly sampled villages in two areas of north and south India to identify people aged 40 and over. Participants attended a clinical examination including lens photography and provided a blood sample for genotyping. Lens images were graded by the Lens Opacification Classification System (LOCS III). Cataract was defined as a LOCS III grade of nuclear >= 4, cortical >= 3, posterior sub-capsular (PSC) >= 2, or dense opacities or aphakia/pseudophakia i…
Development of a pentaplex X-chromosomal short tandem repeat typing system and population genetic studies
2005
Quadruplex and pentaplex systems for polymerase chain reaction amplification of X-chromosomal short tandem repeats DXS101, HPRTB, DXS8377, DXS981 (STRX1) and DXS6789 were developed for automated profiling of liquid and membrane-bound DNA samples. Chinese, Japanese and Thai populations were typed using a quadruplex system, while German and Philippine populations were analyzed using a five-locus system. Out of 88 meioses studied in Philippine family samples at each locus, a possible one repeat deletion (allele 51 to 50) at DXS8377 was observed in a father-daughter pair. Exact tests performed on genotype data from females in the Philippine, German and Thai populations indicated that these grou…
Heterogeneity of the Stearoyl-CoA desaturase-1 (SCD1) Gene and Metabolic Risk Factors in the EPIC-Potsdam Study
2012
Background: Stearoyl-CoA desaturase-1 (SCD1) is an enzyme involved in lipid metabolism. In mice and humans its activity has been associated with traits of the metabolic syndrome, but also with the prevention of saturated fatty acids accumulation and subsequent inflammation, whereas for liver fat content inconsistent results have been reported. Thus, variants of the gene encoding SCD1 (SCD1) could potentially modify metabolic risk factors, but few human studies have addressed this question. Methods: In a sample of 2157 middle-aged men and women randomly drawn from the Potsdam cohort of the European Prospective Investigation into Cancer and Nutrition, we investigated the impact of 7 SCD1 tagg…
Colour polymorphism torn apart by opposing positive frequency-dependent selection, yet maintained in space.
2015
Summary Polymorphic warning signals in aposematic species are enigmatic because predator learning and discrimination should select for the most common coloration, resulting in positive frequency‐dependent survival selection. Here, we investigated whether differential mating success could create sufficiently strong negative frequency‐dependent selection for rare morphs to explain polymorphic (white and yellow) warning coloration in male wood tiger moths (Parasemia plantaginis). We conducted an experiment in semi‐natural conditions where we estimated mating success for both white and yellow male moths under three different morph frequencies. Contrary to expectations, mating success was positi…
Comprehensive exploration of the effects of miRNA SNPs on monocyte gene expression.
2012
We aimed to assess whether pri-miRNA SNPs (miSNPs) could influence monocyte gene expression, either through marginal association or by interacting with polymorphisms located in 3'UTR regions (3utrSNPs). We then conducted a genome-wide search for marginal miSNPs effects and pairwise miSNPs × 3utrSNPs interactions in a sample of 1,467 individuals for which genome-wide monocyte expression and genotype data were available. Statistical associations that survived multiple testing correction were tested for replication in an independent sample of 758 individuals with both monocyte gene expression and genotype data. In both studies, the hsa-mir-1279 rs1463335 was found to modulate in cis the expres…
Contextualising the Last Survivors: Population Structure of Marine Turtles in the Dominican Republic.
2013
Nesting by three species of marine turtles persists in the Dominican Republic, despite historic threats and long-term population decline. We conducted a genetic survey of marine turtles in the Dominican Republic in order to link them with other rookeries around the Caribbean. We sequenced a 740bp fragment of the control region of the mitochondrial DNA of 92 samples from three marine turtle species [hawksbill (n = 48), green (n = 2) and leatherback (n = 42)], and incorporated published data from other nesting populations and foraging grounds. The leatherback turtle (Dermochelys coriacea) in the Dominican Republic appeared to be isolated from Awala-Yalimapo, Cayenne, Trinidad and St. Croix bu…
Genetic polymorphism and high detrimental load in natural populations of Drosophila melanogaster from cellar and vineyard
1987
Two Spanish natural populations of Drosophila melanogaster have been analysed with respect to genetic variability in third chromosome viability. The two populations, although from the same locality, belong to relatively different habitats: the inside of a cellar and a vineyard. The patterns of homozygote and heterozygote viability are similar in both populations. The homozygous detrimental loads estimated are very high and the values for the D:L (detrimental/lethal) ratio close to 2.5, which is higher than any previously found. The environmental variance of viability, average degrees of dominance of lethal genes and of viability polygenes and effective population sizes were estimated in eac…
Emerging genetic patterns of the european neolithic: Perspectives from a late neolithic bell beaker burial site in Germany
2011
The transition from hunting and gathering to agriculture in Europe is associated with demographic changes that may have shifted the human gene pool of the region as a result of an influx of Neolithic farmers from the Near East. However, the genetic composition of populations after the earliest Neolithic, when a diverse mosaic of societies that had been fully engaged in agriculture for some time appeared in central Europe, is poorly known. At this period during the Late Neolithic (ca. 2,8002,000 BC), regionally distinctive burial patterns associated with two different cultural groups emerge, Bell Beaker and Corded Ware, and may reflect differences in how these societies were organized. Ancie…