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PubMed1983

[Medical genetic study of the population or Turkmenia. II. The population structure of the inhabitants of the rural soviet Izgant, Geok-Tepe District, Ashkhabad Province].

This report is devoted to the populational description of the Ashkhabad district. Examination of one of the typical agricultural villages (Izgant of the Ashkhabad district) gave the main parameters of the population. The total number of the inhabitants studied is 1596, the proportion of the studied is 56%, the average family size for the parent with completed reproduction period being 5.47, the average generation time - 33 to 38, the gametic index - 0.67 and the inbreeding coefficient - 0.002267. The distribution of some markers (ABO, MN, Hp, Rh, Pp) have been studied. A rather low coefficient of inbreeding, as a result of the absence of geographical isolation, may account for incidence of autosomal recessive disorders.

Adolescent↗
PubMedDate not supplied

[A population genetics study of the allelic polymorphism in the hypervariable region of the apolipoprotein B gene in the population of different regions of Ukraine].

The allelic variation of the hypervariable locus from 3'-untranslated region of apolipoprotein B gene in healthy volunteers from different regions of Ukraine was analysed. Among 396 DNA samples studied, 13 allelic variants were identified with the number of repeats ranging from 29 to 53. The frequency of alleles varied from 0.0013 to 0.3575 with the mean heterozygosity index 77.9%. The investigation of the genetic differences between 4 populations of different regions of Ukraine has been performed. A high level of the polymorphism and a heterozygosity index of APOB locus allow to recommend this polymorphic system as an informative marker for study of genetic structure population and to forensic medical analysis.

Alleles↗
PubMed1997

Population review: (8). The ethnic minority and overseas-born populations of Great Britain.

This article gives a brief history of immigration into Britain this century as an introduction to a description of the size and main characteristics of the different ethnic minority populations living in Britain today. Using data from the 1991 Census-the first to include a question on ethnic group-the article covers the demographic background and main features of Britain's present-day ethnic minority populations and provides an introduction to the wealth of analyses which has followed the release of ethnicity data from the 1991 Census.

Adolescent↗
PubMed1997

[Population-demographic structure of the population of Kurskaia district. Migration processes].

Analysis of marital structure revealed that 82% of men and 77% of women that contracted marriages in the Kurskaya oblast (administrative region) in 1987-1990 were born in this region. The average coefficient of demographic migration in the Kurskaya oblast was m = 0.345. The majority of migrants to the Kurskaya oblast were from neighboring areas: Central and Central Chernozem Zones of Russia, Ukraine, and Moldova. Marriage assortativeness with respect to the birthplaces of the spouses was K = 0.090. Migration activity increased with urbanization of the population. Migration structure of local populations was determined by mode, level, and direction of interaction between the processes underlying it.

Demography↗
PubMed1987

[On the mobile character of the Malay village population: a feature of the post-settlement population of Galok, Kelantan].

The author examines migration trends in Malay villages. "This report deals with the case of Galok, a settlement opened in the last decade of nineteenth century about 40 kilometers up the Kelantan River, based on field data collected in 1970/71 and 1984." The low rate of population growth due to migration is analyzed, with a focus on the impact of rural-urban migration and changes in household composition. (SUMMARY IN ENG)

Asia↗
PubMedDate not supplied

New data on the genetic structure of the population of Sicily: analysis of the Alia population (Palermo, Italy).

The distribution of 13 genetic markers (AB0, Rh, ACP, ADA, AK, ESD, GLO, PGD, PGMl, SOD, GC, TF, and PI) were studied in a sample from the Alia population of Sicily, Italy. A total of 34 alleles were detected. In comparison with other Sicilian populations, Alia always appeared genetically distinctive, either in terms of overall genetic diversity or for the number of unique alleles present. The results are consistent with previous studies that show no genetic uniformity within the island. More specifically, the data support the genetic divergence of the eastern and western halves of the island and highlight genetic boundaries that run through Sicily and divide it into three distinct areas.

Alleles↗
PubMed1989

Variance within homogeneous phytoplankton populations, III: Analysis of natural populations.

A theoretical framework for interpreting flow cytometric histograms from homogeneous phytoplankton populations was developed in part I of this series of articles and applied to chlorophyll fluorescence histograms from clonal cultures in part II. In this paper, we demonstrate the application of this framework to the analysis of cell volume distributions found in a natural assemblage of phytoplankton from the Gulf of California. Flow cytometric analyses of a surface water sample incubated for a period of 61 h revealed the sequential growth and decline of three distinct subpopulations. Cell volume distributions for each subpopulation measured at different times were analyzed, and the theoretical density function described in parts I and II was fitted to these distributions. The range of cell volumes within each subpopulation was similar to that predicted for asynchronous populations.

Data Interpretation, Statistical↗
PubMed2004

Evaluating bias due to population stratification in case-control association studies of admixed populations.

The potential for bias from population stratification (PS) has raised concerns about case-control studies involving admixed ethnicities. We evaluated the potential bias due to PS in relating a binary outcome with a candidate gene under simulated settings where study populations consist of multiple ethnicities. Disease risks were assigned within the range of prostate cancer rates of African Americans reported in SEER registries assuming k=2, 5, or 10 admixed ethnicities. Genotype frequencies were considered in the range of 5-95%. Under a model assuming no genotype effect on disease (odds ratio (OR)=1), the range of observed OR estimates ignoring ethnicity was 0.64-1.55 for k=2, 0.72-1.33 for k=5, and 0.81-1.22 for k=10. When genotype effect on disease was modeled to be OR=2, the ranges of observed OR estimates were 1.28-3.09, 1.43-2.65, and 1.62-2.42 for k=2, 5, and 10 ethnicities, respectively. Our results indicate that the magnitude of bias is small unless extreme differences exist in genotype frequency. Bias due to PS decreases as the number of admixed ethnicities increases. The biases are bounded by the minimum and maximum of all pairwise baseline disease odds ratios across ethnicities. Therefore, bias due to PS alone may be small when baseline risk differences are small within major categories of admixed ethnicity, such as African Americans.

Black or African American↗
PubMed2001

Population based linkage disequilibrium mapping of QTL: an application to simulated data in an isolated population.

Despite successes in mapping and cloning genes involved in rare Mendelian diseases, genetic dissection of quantitative traits into single Mendelian factors still remains a challenging task. As the dense map of single nucleotide polymorphism (SNP) markers becomes available in the near future, linkage disequilibrium (LD) mapping will become one of major tools for mapping and identifying quantitative trait loci (QTL). In this report, we present a population-based linkage disequilibrium mapping of QTL. This method unifies the analysis of mapping QTL in humans and in model organisms and can be used for randomly sampled individuals. The proposed method is applied to search for polymorphism sites within the candidate genes 2 and 6, which influence quantitative traits Q1 and Q2 or Q5, in a simulated data set in an isolated population.

Chromosome Mapping↗
PubMed2002

The relation between lysosomal biomarker and population responses in a field population of Microchaetus sp. (oligochaeta) exposed to the fungicide copper oxychloride.

The ecological relevance of the neutral red retention assay as a biomarker in an indigenous earthworm population (Microchaetus sp.) exposed to the fungicide copper oxychloride was investigated. Changes in earthworm biomass and numbers were monitored and related to changes in neutral red retention times of coelomocytes as well as changes in copper concentrations in the soil and earthworm body tissues. Results indicated that Microchaetus sp. responded sensitively to the copper oxychloride by showing an initial decrease in biomass 2 months after spraying started. This was followed by a significant decrease in worm numbers after 3 months. The neutral red retention times of earthworm coelomocytes decreased significantly within the first month of treatment and correspond to a significant increase in soil copper concentrations, but not with an immediate increase in body burdens of copper. More than a year after spraying had stopped the worm biomass and numbers were still significantly lower in the treated plots compared with the control plots. Since the reduction in neutral red retention times could be attributed to the presence of copper oxychloride and preceded the decline in population density and biomass, we conclude that this biomarker has a useful role to play in environmental risk assessment and could provide a warning of impending ecological damage.

Animals↗
PubMed1996

Population data for the STR systems HumTH01, HumVWA and FES/FPS in a population sample from lower Franconia.

Population data studies for the three tetranucleotide STR systems HumTH01, HumVWA and FES/ FPS were carried out on a Caucasian population sample from Lower Franconia (Germany). The observed heterozygosities were 0.83, 0.80 and 0.73, respectively, and the discrimination power of the triplex was 0.9995. All loci were in accordance with Hardy-Weinberg equilibrium tested using the chi 2-analysis.

Alleles↗
PubMed1996

On the theory of partially inbreeding finite populations. IV. The effective population size for polyploids reproducing by partial selfing.

Consider a population of size N in which there is reproduction by selfing with probability beta and by random mating with probability 1-beta. In each cell of any individual, homologous chromosomes appear 2n times, with n among them having been contributed by each parent. Wright [Proc. Natl. Acad. Sci. 24:372 (1938)] showed that if beta = 0, there is no double reduction in gamete formation, and a Poisson offspring distribution, the probability of nonidentity by descent of two random copies of a gene in an individual of generation t + 1 is approximately 1-1/2nN times as large as it is in generation t if N is large. This result will be generalized to populations with any beta > or = 0 and any offspring distribution. If n = 2 or 3, a result will be obtained that also holds for any probability of double reduction.

Inbreeding↗
PubMed1987

Dynamics of populations with changing rates: generalization of the stable population theory.

A general and complete exposition of the dynamics of populations with changing vital rates is given in the discrete time formulation. Results obtained are stronger than Lopez's or Hajnal's. In addition to the proof of existence of limits, an explicit expression for the age distribution is obtained by considering forward products of population projection matrices, while an explicit expression for the generalized reproductive values is obtained by considering backward products. The forward and backward characteristic equations respectively determine the forward and backward growth rates. The relative age distribution is compared to the alternative expression of Y.J. Kim (1986, Demography 23 (3), 451-461), which is the discrete version of S.H. Preston and A.J. Coale (1982, Pop. Index 48 (2), 217-259).

Aging↗
PubMed1996

Comparison of German population data on the apoB-HVR locus with other Caucasian, Asian and black populations.

A population study of 505 unrelated individuals from Southwestern Germany was carried out on the 3'-apoB hypervariable region (HVR). After amplification via polymerase chain reaction (PCR) and agarose gel electrophoresis, 15 different alleles and 47 genotypes were observed. The most common alleles were hypervariable elements (HVE) 37 and 35 with an allele frequency of 0.374 and 0.244, respectively. The heterozygosity index was calculated to be 78.4%. Allele frequencies of this study are compared with results from other databases obtained from a French, a Spanish, an Asian and an American (Black) population.

Alleles↗
PubMed2004

The prognosis of impaired left ventricular systolic function and heart failure in a middle-aged and elderly population in an urban population segment of Copenhagen.

AIMS: To determine the prognosis, total mortality and cardiac morbidity, of patients with left ventricular systolic dysfunction and heart failure (HF) in a general population sample. METHODS AND RESULTS: A total of 764 subjects, 432 females and 332 males, median age (range) 66 years (50-89), participated in this cross sectional survey. The study population was recruited from randomly selected general practitioners and stratified to include a minimum of 150 persons in each age decade stratum. Each participant filled in a heart failure questionnaire and ECG, blood tests and echocardiography were performed. Median (range) follow-up was 1145 (51-1197) days. Subjects with LVEF < or = 0.40 had a significantly higher all-cause mortality (27.8% vs. 5.6%, P<0.0001), admission rate for HF (25.0% vs. 1.9%, P<0.0001) and for other cardiac causes (25.0% vs. 6.3%, P<0.0001) than in subjects with LVEF>0.40. The age and gender adjusted 2-year relative risk of death was 4.6 (95% C.I.=1.6-13.2). No significant difference in mortality was found between subjects with or without heart failure symptoms. CONCLUSION: Significantly higher mortality as well as cardiac morbidity was found in subjects with symptomatic and asymptomatic LV systolic dysfunction compared to those with normal systolic function. These conditions were among the strongest predictors of all-cause mortality and cardiac morbidity.

Aged↗
PubMed2004

Population data for 16 Y-chromosome STRs in four populations from Pyrenees (Spain).

Population frequencies for the eight Y-STR loci included in the "minimal haplotype" from Y-STR Haplotype Reference Database (YHRD) plus other eight Y-STRs (DYS434, DYS435, DYS436, DYS437, DYS438, DYS439, GATA H4 and GATA A10) were obtained for a sample of 133 males from four main geographical areas in the Pyrenees (Spain): Vall D'Aran (Lérida), Cerdanya (Gerona), Alt Urgell (Lérida) and Jacetania (Huesca). Haplotype diversities were estimated in the four populations.

Chromosomes, Human, Y↗
PubMed2005

Population genetics of Y-chromosome STRs in a population sample of the Lithuanian minority residing in the northeastern Poland.

Haplotype and allele frequencies for the 12 Y-STRs were determined in a population sample of 124 unrelated males--members of the Lithuanian minority residing in the northeastern Poland. Three of the haplotypes were encountered in duplicate, while 118 haplotypes were unique. The overall gene diversity was 0.9952. Analysis of molecular variance revealed that the Lithuanian minority can be distinguished from the autochthonous Poles, although these two populations are very close to each other. This database study provides an essential precondition for applying Y-chromosomal STRs estimates in forensic identification of male DNA and tracing of paternal lineages.

Chromosomes, Human, Y↗