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At least 19 recordsLinked to original sources
PubMed1976

On the genetics and population genetics of Gm(4).

Investigations on 70 German families with 142 children confirmed the autosomal-dominant inheritance of Gm(4). However, in our material as well as in the materials published so far, Gm(4) X Gm(-4) parental combinations show clear surplusses of Gm(4) and deficits of Gm(-4) children, which might indicate prenatal selection. The world distribution of Gm4 alleles reveals a remarkable racial heterogeneity. Furthermore, marked North-South distribution gradients in Caucasoids and Mongoloids were found. The genetical and population genetical observations are discussed.

Adult↗
PubMed1979

Human pancreatic amylase polymorphism: formal genetics and population genetics.

The genetically determined polymorphism of human pancreatic amylase (E.C. 3.2.1.1), AMY2, is demonstrated in serum specimens by agarose gel electrophoresis. We investigated 325 mother-child pairs and 2594 unrelated individuals from southwestern Germany. This study confirms the formal hypothesis of two common alleles AMY1/2, AMY2/2 and possibly two rare alleles AMY3/2, AMY4/2 at an autosomal locus AMY2. The frequency of the AMY1/2 allele was calculated as 0.951; AMY3/2 and AMY4/2 seem to have a frequency of 0.001 in this sample.

Alleles↗
PubMed2026

plinkQC: an integrated tool for ancestry inference, sample selection, and quality control in population genetics.

MOTIVATION: Population genetic analyses rely on high quality datasets that pass rigorous controls for sample and marker quality. Many analyses also require additional processing including identification of ancestry and sample relatedness. A software package that addresses all these common, yet crucial tasks is missing. RESULTS: We have developed plinkQC, an R/CRAN package that combines these functionalities into a single software package with detailed vignettes for example applications. plinkQC determines the ancestry of study samples via a pre-trained random forest classifier that reaches 98% performance accuracy with just 5% of marker overlap between reference and user data. To obtain the maximal set of unrelated study samples, we developed a graph-based pruning method, taking both relationship estimates and sample quality into account. We demonstrate optimal sample selection on the 1000 Genomes project, where we retain an additional 71 samples compared to publicly available exclusion lists. Finally, plinkQC bundles these results together with per-individual and per-marker quality control checks into three simple functions and returns both the quality controlled dataset and quality control report about each step of the analysis. AVAILABILITY AND IMPLEMENTATION: plinkQC is available as an R/CRAN package. The documentation and code are available on github: https://meyer-lab-cshl.github.io/plinkQC/ and https://github.com/meyer-lab-cshl/plinkQC_manuscript.

Software↗
PubMed1979

[Population genetics of the population of the northern European RSFSR. III. Demographic and genetic characteristics of two rural communities of the Pinezhskii District of the Arkhangel'sk Region].

The paper deals with the distribution of genetic markers (systems ABO, Rh, Hp, PTC) and a number of phenotyping traits (folding of arms, hand clasping, tongue rolling, right- and left-handedness, the type of ear lobe, the types of dermatoglyphics patterns) in the inhabitants of 5 villages in the Pinezhsky district of the Arkhangelsky region of the RSFSR. The data presented in this work were obtained in the course of examination of over 900 persons. Among the systems analysed there was a statistically significant deviation from Hardy-Weinberg's equlibrium. It took place in two the least villages. In one case--for ABO blood groups, in another--for Hp system. There are an interesting fact of the excess of heterozygotes 2-1 and some excess of the group 0. Statistically significant differences between villages were shown for four genetic systems. Data on migrations, distribution of gene frequencies and estimated genetic and phenotype distances between villages of the same village community and between two communities suggest, that each village community can be considered as separate subdivided population. Considering the uniformity of the environmental pressure in the region examined, the heterogeneity of the population studied is apparently associated with a random genetic drift.

Blood Group Antigens↗
PubMed1979

[Population genetics of the population of the European north of the RSFSR. IV. The level of blood relationship in 5 villages of Pinega District, Archangel Province].

Computer program "RODAN-1" is used for inbreeding coefficient estimation. The population studied consists of two communities of 5 villages. 385 marriages were computed. The coefficient of inbreeding is 0.00145 for pedigree for rural Russian population (the Arkhangelsk region). The inverse dependence between a village size and corresponding data of inbreeding coefficient is suggested. An attempt was undertaken to estimate the genealogical information value for each pedigree and average information value for a village.

Arctic Regions↗
PubMed1992

Origin of the Koreans: a population genetic study.

A population genetic study was undertaken to investigate the origin of Koreans. Thirteen polymorphic and 7 monomorphic blood genetic markers (serum proteins and red cell enzymes) were studied in a group of 437 Koreans. Genetic distance analyses by both cluster and principal components models were performed between Koreans and eight other populations (Koreans in China, Japanese, Han Chinese, Mongolians, Zhuangs, Malays, Javanese, and Soviet Asians) on the basis of 47 alleles controlled by 15 polymorphic loci. A more detailed analysis using 65 alleles at 19 polymorphic loci was performed on six populations. Both analyses demonstrated genetic evidence of the origin of Koreans from the central Asian Mongolians. Further, the Koreans are more closely related to the Japanese and quite distant from the Chinese. The above evidence of the origin of Koreans fits well with the ethnohistoric account of the origin of Koreans and the Korean language. The minority Koreans in China also maintained their genetic identity.

Alleles↗
PubMed2026

Differences in structural color and population genetic structure of Western and Central Palearctic Polyommatus icarus populations.

The blue structural coloration of male Polyommatus icarus butterflies functions as a sexual signaling trait and exhibits remarkable spectral stability within populations despite being generated by highly complex photonic nanoarchitectures. The correlation of the blue sexual signaling color and population genetic variation of the butterflies was investigated across the Western and Central Palearctic regions. Dorsal wing reflectance spectra was measured for 95 male specimens and compared with the population genetic structure revealed in 99 specimens by 18 recently developed microsatellites. Reflectance measurements indicated a clear separation between the European and Central Asian populations, consistent with our previous findings, while the intermediate populations near the Ural Mountains exhibited distinct European spectral characteristics. In contrast, genetic variation showed limited structuring and correlated primarily with geographic distance, as indicated by a significant isolation-by-distance pattern. Thus, although both reflectance and genetic variations are geographically structured, spectral properties are only weakly correlated with genetic differentiation. Populations near the Ural Mountains exhibited genetic ancestry linked to Central Palearctic groups, while displaying distinct Western Palearctic coloration, suggesting that the focal species' sexual signaling is strongly influenced by local factors. These findings suggest that sexual signaling coloration may evolve at least partially independently of the neutral genetic background, offering additional insight into evolutionary divergence across broad geographic scales.

Animals↗
PubMed1977

[Medico-genetic study of the population of the Samarkand region. II. Population-genetic description of 4 kishlaks of the Urgut district].

This report is a second one in a series of works devoted to the medico-genetical screening of Uzbekistan populations. The paper comprises the results of the analysis of the populational structure of one of the village councils (soviets) of the Urgut District of the Samarkand Region. The main parameters of the population studied were as follows: total number 1529 persons, the average number of inhabitants of one village--328. The proportion of the inhabitants studied--56%, the average number of persons per family--5.22; the average period between subsequent generations--30-35 years, the gametic index--0.8, the inbreeding coefficient inferred from pedigrees--0.018899--0.00781, Fst = 0.03577, the average genetic distanse according to Edwards--0.0231-0.0671. The distribution of Mendelian markers (ABO, Rh, Hp and Ptc) was studied. The observed ratio between a high degree of inbreeding and a relatively low extent of isolation of populations permits to explain satisfactorily the distribution and frequencies of hereditary pathology in the Urgut District of the Samarkand Region pointed out in the previous report.

Adolescent↗
PubMed1975

Population genetic studies in bees (APIDAE, Hymenoptera). I. Genetic load.

Three populations of Apis mellifera each predominantly of a different subspecies (mellifera, ligustica and adansonii) and 7 species of stingless bees (Meliponinae, Apidae) were manipulated for applying the MORTON, CROW & MULLER's methodology in order to estimate the lethal equivalents (B) of each population. A total of 249 queens were used, 27 being meliponids and 222 Apis mellifera. The populations of Apis have a B that does not differ significantly when they are compared to each other (1.29, 1.36, 1.32) and the balanced average equals 1.33. When the x-alleles are not considered, this balanced value is 0.262. The figures for B in the seven species of stingless bees ranged between 0.104 and 0.159 with balanced average of 0.132. The main reason for this smaller load in meliponids may rest in their effective population numbers, which are smaller than those of Apis. The average mortality for diploid females (0.141) and for haploid males (0.163) allows the estimation of the total elimination (sigma E = 0.073). Since for haplo-diploid systems the total mutation rate is sigma mu = 2 sigma E divided by 3 the figure 0.048 is obtained. Since about 15% of the genes in Apis mellifera are sex limited, this value of sigma mu should be added of 0.0072 (that is 0.15 X 0.048) and then, the total mutation rate becomes 0.055. Using a quite different method, the one by MORTON, CROW & MULLER, the figure 0.076 was obtained. If a mutation rate of 10(-5) is assumed, the number of genes in Apis mellifera that can make a contribution to the genetic load would vary between 5,500 and 7,600.

Animals↗
PubMed1979

[Correlation of heredity and environmental factors in the etiology of Vilyui encephalomyelitis. II. A population genetic study in districts of Vilyui encephalomyelitis distribution].

Population-genetic investigation was carried out in the regions endemic for Viljuisk encephalomyelitis (VE). The following indices were estimated: the relationship coefficient, the inbreeding coefficient, the intensity of migration, genetic structure of the population. The aim of the investigation was to explain causes of intrapopulational and, in some cases, of intragenus accumulation of the VE patients. No evidence of isolation or increased inbreeding were found in highly affected populations. The genetic structure of a group of VE patients tested for 9 polymorphic systems did not reveal any deviation from the control group. Several VE cases in healthy populations occured in some years after the immigration of a VE patient. These data confirm the hypothesis that VE is transmitted from a VE patient to healthy persons. Among these persons fall ill those who have a hereditary determined increased sensitivity to VE which results in intrapopulation and intragenus accumulation of VE cases.

Adult↗
PubMed1992

An optimizing principle of natural selection in evolutionary population genetics.

This paper brings together two themes in evolutionary population genetics theory. The first concerns Fisher's Fundamental Theorem of Natural Selection: a recent interpretation of this theorem claims that it is an exact result, relating to the so-called "partial" increase in mean fitness. The second theme concerns the desire to find an optimality principle in genetic evolution. Such a principle is found here: of all gene frequency changes which lead to the same partial increase in mean fitness as the natural selection gene frequency changes, the natural selection values minimize a generalized distance measure between parent and daughter generation gene frequency values.

Alleles↗