1,041 research outputs found
Mendelian breeding units versus standard sampling strategies: Mitochondrial DNA variation in southwest Sardinia
We report a sampling strategy based on Mendelian Breeding Units (MBUs), representing an interbreeding group of individuals sharing a common gene pool. The identification of MBUs is crucial for case-control experimental design in association studies. The aim of this work was to evaluate the possible existence of bias in terms of genetic variability and haplogroup frequencies in the MBU sample, due to severe sample selection. In order to reach this goal, the MBU sampling strategy was compared to a standard selection of individuals according to their surname and place of birth. We analysed mitochondrial DNA variation (first hypervariable segment and coding region) in unrelated healthy subjects from two different areas of Sardinia: the area around the town of Cabras and the western Campidano area. No statistically significant differences were observed when the two sampling methods were compared, indicating that the stringent sample selection needed to establish a MBU does not alter original genetic variability and haplogroup distribution. Therefore, the MBU sampling strategy can be considered a useful tool in association studies of complex traits
Comparative growth and static allometry in the genus Chlorocebus
Characterizing variation in growth across populations is critical to understanding multiple aspects of development in primates, including within-taxon developmental plasticity and the evolution of life history patterns. Growth in wild primates has often been reported and directly compared across larger taxonomic groups and within social groups, but comparisons are rarely investigated across widely dispersed populations of a single taxon. With the Vervet Phenome-Genome Project and the International Vervet Research Consortium, we trapped 936 vervet monkeys of all ages representing three populations (Kenyan pygerythrus, South African pygerythrus, and sabaeus from St. Kitts & Nevis). We gathered 10 different body measurements from each including mass, body breadth and length, segmental limb lengths, and chest circumference. To gain a better understanding of how ontogenetic patterns vary in these populations, we calculated bivariate allometry coefficients, derived using PCA on log-transformed and z-standardized trait values, and compared them to isometric vector coefficients. Within all population samples, around weaning age most traits showed a negative allometric relationship to body length. As each population ages, however, distinct patterns emerge, showing population differences in onset and intensity of growth among traits. In concordance with other analyses on growth in these populations, our results suggest that there exist relative differences in patterns of growth between Chlorocebus populations, further suggesting selection for unique developmental pathways in each
Criminal Victimisation and Depression in the Czech Republic
Since the fall of communism in 1989, criminal victimization has become an issue in the Czech Republic, & research indicates that it is a stressful experience. The relationship between criminal victimization & depression was examined by adding fear of crime, protection against crime, avoidance of crime, mastery over one's life, social support, & trust in government (as well as sociodemographic controls) to successive regression equations. A total of 703 Czech households in the second of a three-wave (1994-1996) panel study were studied. For men, the total & direct effects of criminal victimization on depression were significant. However, the relation of men's fear of crime & depression was mediated by avoidance. For women, criminal victimization was not related to depression. The relation of women's fear of crime & depression was mediated by mastery. Interpretations of these results are grounded in the different relevance criminal victimization has for the well-being of men & women
Genetic diversity of North American captive-born gorillas (Gorilla gorilla gorilla)
Western lowland gorillas (Gorilla gorilla gorilla) are designated as critically endangered and wild populations are dramatically declining as a result of habitat destruction, fragmentation, diseases (e.g., Ebola) and the illegal bushmeat trade. As wild populations continue to decline, the genetic management of the North American captive western lowland gorilla population will be an important component of the long‐term conservation of the species. We genotyped 26 individuals from the North American captive gorilla collection at 11 autosomal microsatellite loci in order to compare levels of genetic diversity to wild populations, investigate genetic signatures of a population bottleneck and identify the genetic structure of the captive‐born population. Captive gorillas had significantly higher levels of allelic diversity (t7 = 4.49, P = 0.002) and heterozygosity (t7 = 4.15, P = 0.004) than comparative wild populations, yet the population has lost significant allelic diversity while in captivity when compared to founders (t7 = 2.44, P = 0.04). Analyses suggested no genetic evidence for a population bottleneck of the captive population. Genetic structure results supported the management of North American captive gorillas as a single population. Our results highlight the utility of genetic management approaches for endangered nonhuman primate species
Sexual Behavior of Immature Tibetan Macaques (\u3ci\u3eMacaca thibetana\u3c/i\u3e)
Tibetan macaque sociosexual behavior begins in infancy, and comprises many of their initial interactions with other group members as infants. Tibetan macaques possess a large sociosexual behavioral repertoire, including a behavior called bridging, which involves infants and juveniles, and is found in only four species. Immature macaques differ in the types, rate, and partner preferences across a variety of behaviors. This study compared rates of sexual behavior among four age and sex classes of 26 immature Tibetan macaques at Mt. Huangshan, China. A total of 643 sex behaviors were observed and evaluated for 5 parameters: total sex behavior rates, initiation rates, rates of different types of sexual behavior, partner preference, and rates within different social contexts. Nine types of sex behaviors were observed with bridging being the most common (n = 179) and self-genital manipulation being the least common (n = 18)(H7 = 38.6, p \u3c 0.05). Sex behaviors occurred at the highest rate within spontaneous (2.9 sex behaviors per hour) and play (2.2 sex behaviors per hour) social contexts relative to grooming, aggressive, and self-directed contexts (H4 = 72.4, p \u3c 0.05). Generally, younger males exhibited higher rates of sex behavior relative to other immature classes across all five aspects, and younger females exhibited lower rates of sex behavior relative to other immature classes across all five aspects. Immature Tibetan macaques engage in many sex behaviors with both immature and adult group members. Further studies are needed on the long-term effects of immature sexual behavior regarding its function and influence on social rank and reproductive success
The Acetabular Wall Index for Assessing Anteroposterior Femoral Head Coverage in Symptomatic Patients
Background: Understanding acetabular pathomorphology is necessary to correctly treat patients with hip complaints. Existing radiographic parameters classify acetabular coverage as deficient, normal, or excessive but fail to quantify contributions of anterior and posterior wall coverage. A simple, reproducible, and valid measurement of anterior and posterior wall coverage in patients with hip pain would be a clinically useful tool. Questions/Purposes: We (1) introduce the anterior wall index (AWI) and posterior wall index (PWI), (2) report the intra- and interobserver reliability of these measurements, and (3) validate these measurements against an established computer model. Methods: We retrospectively reviewed 87 hips (63 patients) with symptomatic hip disease. A validated computer model was used to determine total anterior and posterior acetabular coverage (TAC and TPC) on an AP pelvis radiograph. Two independent observers measured the AWI and PWI on each film, and the intraclass correlation coefficient (ICC) was calculated. Pearson correlation was used to determine the strength of linear dependence between our measurements and the computer model. Results: Intra- and interobserver ICCs were 0.94 and 0.99 for the AWI and 0.81 and 0.97 for the PWI. For validation against the computer model, Pearson r values were 0.837 (AWI versus TAC) and 0.895 (PWI versus TPC). Mean AWI and PWI were 0.28 and 0.81 for dysplastic hips, 0.41 and 0.91 for normal hips, 0.61 and 1.15 for hips with a deep acetabulum. Conclusions: Our data suggest these measures will be helpful in evaluating anterior and posterior coverage before and after surgery but need to be evaluated in asymptomatic individuals without hip abnormalities to establish normal ranges. Level of Evidence: Level III, diagnostic study. See Instructions for Authors for a complete description of levels of evidenc
Economic Change and Change in Well-Being in the Czech Republic, with Comparisons to Married Women in the United States
Examines the effects of economic change on individual well-being for a panel of married Czech women compared with a US sample from IA (N = 192 & 386, respectively, in 1990/91). Questionnaire data show that respondents who were forced to make economic adjustments reducing their standard of living also reported increased health problems & depressive symptoms. Contrary to some US findings the relationship between economic adjustments & change in depressive symptoms was strongest among those who reported having the strongest sense of personal control (mastery) & the highest perceived social support. Compared with the US sample, married Czech women reported more depressive symptoms, had more health problems, & were lower in feelings of mastery. In addition, Czech women recorded significantly stronger paths linking education to changes in health conditions & depressive symptoms, whereas US women had significantly stronger paths linking actual economic conditions to subsequent economic adjustments. Data suggest that the US stress-distress model applies in the Czech Republic as well, but further understanding of the differentiated role of social support & mastery for Czech & US women is necessray to more completely interpret the observed interactions
Genetic Analysis of Putative Familial Relationships in a Captive Chimpanzee (Pan troglodytes) Population
Twelve autosomal dinucleotide repeat loci were analyzed in chimpanzees genomes by DNA amplification using primers designed for analysis of human loci. The markers span the entire length of human chromosomes 21 and 22. Nine markers were polymorphic in chimpanzee as well, with a somewhat comparable level of polymorphism and allele size range. Even in the presence of very limited information and in spite of missing samples, it was possible to reconstruct a complex pedigree and to provide molecular data that corroborate family relationships that were deduced from cage history
and behavioral data. The conclusions were further supported by mitochondrial DNA analysis. The data presented in this report show that the extremely abundant source of human markers may be exploited to validate, with molecular evidence, hypotheses on individual relationship or alleged pedigrees, based upon behavioral observations
Genetic Analysis of Putative Familial Relationships in a Captive Chimpanzee (\u3ci\u3ePan troglodytes\u3c/i\u3e) Population
Twelve autosomal dinucleotide repeat loci were analyzed in chimpanzees genomes by DNA amplification using primers designed for analysis of human loci. The markers span the entire length of human chromosomes 21 and 22. Nine markers were polymorphic in chimpanzee as well, with a somewhat comparable level of polymorphism and allele size range. Even in the presence of very limited information and in spite of missing samples, it was possible to reconstruct a complex pedigree and to provide molecular data that corroborate family relationships that were deduced from cage history and behavioral data. The conclusions were further supported by mitochondrial DNA analysis. The data presented in this report show that the extremely abundant source of human markers may be exploited to validate, with molecular evidence, hypotheses on individual relationship or alleged pedigrees, based upon behavioral observations
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