• Title/Summary/Keyword: population structure

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Single nucleotide polymorphism-based analysis of the genetic structure of the Min pig conserved population

  • Meng, Fanbing;Cai, Jiancheng;Wang, Chunan;Fu, Dechang;Di, Shengwei;Wang, Xibiao;Chang, Yang;Xu, Chunzhu
    • Animal Bioscience
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    • v.35 no.12
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    • pp.1839-1849
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    • 2022
  • Objective: The study aims to uncover the genetic diversity and unique genetic structure of the Min pig conserved population, divide the nucleus conservation population, and construct the molecular pedigree. Methods: We used KPS Porcine Breeding Chip v1 50K for SNP detection of 94 samples (31♂, 63♀) in the Min pig conserved population from Lanxi breeding Farm. Results: The polymorphic marker ratio (PN), the observed heterozygosity (Ho), and the expected heterozygosity (He) were 0.663, 0.335, and 0.330, respectively. The pedigree-based inbreeding coefficients (FPED) was significantly different from those estimated from runs of homozygosity (FROH) and single nucleotide polymorphism (FSNP) based on genome. The Pearson correlation coefficient between FROH and FSNP was significant (p<0.05). The effective population content (Ne) showed a continuously decreasing trend. The rate of decline was the slowest from 200 to 50 generations ago (r = 0.95), then accelerated slightly from 50 to 5 generations ago (1.40

Phylogeography and Population Genetic Structure of Amur Grayling Thymallus grubii in the Amur Basin

  • Ma, Bo;Lui, Tingting;Zhang, Ying;Chen, Jinping
    • Asian-Australasian Journal of Animal Sciences
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    • v.25 no.7
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    • pp.935-944
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    • 2012
  • Amur grayling, Thymallus grubii, is an important economic cold freshwater fish originally found in the Amur basin. Currently, suffering from loss of habitat and shrinking population size, T. grubii is restricted to the mountain river branches of the Amur basin. In order to assess the genetic diversity, population genetic structure and infer the evolutionary history within the species, we analysised the whole mitochondrial DNA control region (CR) of 95 individuals from 10 rivers in China, as well as 12 individuals from Ingoda/Onon and Bureya River throughout its distribution area. A total of 64 variable sites were observed and 45 haplotypes were identified excluding sites with gaps/missing data. Phylogenetic analysis was able to confidently predict two subclade topologies well supported by maximum-parsimony and Bayesian methods. However, basal branching patterns cannot be unambiguously estimated. Haplotypes from the mitochondrial clades displayed local homogeneity, implying a strong population structure within T. grubii. Analysis of molecular variance detected significant differences among the different geographical rivers, suggesting that T. grubii in each river should be managed and conserved separately.

Genetic Variation and Population Structure of Alder (Alnus hirsuta : Betulaceae) in Korea

  • Park, Joo-Soo;Huh, Man-Kyu
    • Journal of Life Science
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    • v.10 no.1
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    • pp.14-19
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    • 2000
  • Variation at 25 allozyme loci in Korean wateralder (Alnus hirsuta Rupr.) from nine distinct populations was measured to estimate the amount and pattern of genetic diversity and population structure. The mean genetic diversity within population was 0.166. Korean alder populations have slightly high levels of genetic diversity compared to those present in associated temperature-zone species and two Canadian alder species. Among population s genetic differentiation accounted for an significant 9% of the total variation. High gene flow(Nm=2.63) was observed. Analysis of fixation indices, calculated for all polymorphic loci in each population, showed a substantial deficiency of heterozygotes relative to Hardy-Weinberg expectations. The mean GST value A. hirsuta in Korea (GST = 0.087) is similar to those of A. rogosa in Canada (GST = 0.052). These low values of GST in two countries. reflecting little spatial genetic differentiation, may indicate extensive gene flow (via pollen and/or seeds) and/or recent colonization. These factors reduce the effect of geographic isolation of breeding and the chance for genetic divergence. A pattern of increasing is observed with increasing rainfall per year. Regression analysis indicates that 54% (F = 4.67) of the variability observed can be explained by this relationship.

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Genetic Structure of the Jellyfish Rhopilema esculentum (Scyphozoa: Rhizostomatidae) in Korean Coastal Waters

  • Soo-Jung Chang;Jang-Seu Ki;Won-Duk Yoon;Ga-Eun Jun
    • Animal Systematics, Evolution and Diversity
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    • v.39 no.4
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    • pp.264-271
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    • 2023
  • The edible jellyfish Rhopilema esculentum occurs in waters throughout northeastern Asia, including in Korea, China, and Japan. In Korean waters, R. esculentum has appeared in two regions (Gangwha and Muan). Based on the appearance of young medusae and coastal distribution records, these two regions may be key R. esculentum breeding sites. In the present study, we investigate and compare the genetic structure of R. esculentum in the two regions using mitochondrial sequences (16S ribosomal RNA and cytochrome c oxidase subunit I). The genetic diversity of the R. esculentum population at Ganghwa exceeded that of the population at Muan. Despite considerable geographic separation (400 km) between the two regions(Gangwha and Muan), our haplotype network suggests that the Gangwha and Muan populations of R. esculentum are related. The simple and monotonous genetic structure of the Muan population shows that R. esculentum emergence is relatively recent. In contrast, the Gangwha population shows evolution. Moreover, jellyfish of the Gangwha population are genetically diverse and remain constant despite environmental fluctuations in the Han River. The Gangwha area is considered to be the old origin of R. esculentum in Korea.

Population size, group and age structure of geladas (Theropithecus gelada) in escarpments of Eastern Tigray, Ethiopia: implication for conservation

  • Girmay, Teklay;Dati, Deribe
    • Journal of Ecology and Environment
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    • v.44 no.3
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    • pp.178-184
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    • 2020
  • Background: Geladas (Theropithecus gelada), endemic to Ethiopia, are distributed closely related to the escarpments and gorge systems of the country, and large populations are found in the Simien Mountain National Park. This study was conducted in Eastern Tigray, Northern Ethiopia, from February 2018 to August 2019 in order to determine population size and composition of geladas. Total count method was used to estimate the population structure of geladas. Observations of the group of geladas based on body size and morphological characteristics were used to classify age and sex categories of the population. SPSS Version 20 was used to analyze the data. Chi-square test was used to compare sex ratio of geladas and population size among the counting sites between wet and dry seasons. Results: A total of 112 and 99 individual of geladas were counted during wet and dry seasons, respectively. Of the average gelada population recorded in this study, 11.4% were adult males, 30.3% were adult females, 12.8% were sub-adult males, 25.6% were sub-adult females, and 19.9% were unidentified juveniles. However, there was no statistically significant difference among the various age and sex groups of geladas counted during wet and dry season (χ2 = 2.6, DF = 4, P > 0.05). Variations of group size along seasons were observed in this study. Sex ratio of adult male to adult female was 1:2.6 and 1:2.7 during the dry and wet seasons, respectively. Conclusion: Very small gelada population size was recorded in the current study. An average of 105.5 geladas was recorded during the study period. As this is the first report of gelada population in escarpments of Eastern Tigray, population trend of the geladas cannot decide based on the current study.

Excess zinc uptake in Paronychiurus kimi(Collembola) induces toxic effects at the individual and population levels

  • Son, Jino;Lee, Yun-Sik;Kim, Yongeun;Wee, June;Ko, Euna;Cho, Kijong
    • Korean Journal of Environmental Biology
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    • v.37 no.3
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    • pp.335-342
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    • 2019
  • The purpose of this study was to investigate the toxic effects of zinc in collembolan Paronychiurus kimi at the individual (survival and juvenile production) and population (population growth and age structure) levels after 28 days of exposure in artificially spiked soil. These toxic effects were interpreted in conjunction with the internal zinc concentrations in P. kimi. The EC50 value for juvenile production based on the total zinc concentration was 457 mg Zn kg-1 dry soil, while the LC50 value for adult survival and ri=0 value for population growth were within the same order of magnitude (2,623 and 1,637 mg Zn kg-1 dry soil, respectively). Significant differences in adult survival, juvenile production, and population growth compared with the control group were found at concentrations of 1,500, 375, and 375 mg Zn kg-1 dry or higher, respectively, whereas significant differences in the age structure, determined by the proportion of each age group in the population, were observed in all treatment groups. It appeared that the internal zinc level in P. kimi was regulated to some extent at soil zinc concentrations of ≤375 mg Zn kg-1 dry soil, but not at high soil zinc concentrations. These results indicate that, despite zinc being regulated by P. kimi, excess zinc exceeding the regulatory capacity of P. kimi can trigger changes in the responses at the individual and population levels. Given that population dynamics are affected not only by individual level but also by population level endpoints, it is concluded that the toxic effects of pollutants should be assessed at various levels.

Discussion: A Study on the Population Structure of Democratic People's Republic of Korea

  • Kim, Keewhan
    • Communications for Statistical Applications and Methods
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    • v.22 no.1
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    • pp.15-18
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    • 2015
  • Reunification, (considered a 'bonanza'), is often expected to bring economic and social benefits as well as solutions to the population aging problem; consequently, the study on the population structure of North Korea is salient. This paper reviews and talks on the North Korean population and implications. In view of reliability and consistency, the North Korean population appears at an explicit change compared to the past, and shows significant differences from the South, implying that it needs significant resources to integrate during reunification. Therefore, it is opportune to discuss the North Korean population prior to the clamor for the reunification.

Human Population Admixture in Asia

  • Xu, Shuhua
    • Genomics & Informatics
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    • v.10 no.3
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    • pp.133-144
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    • 2012
  • Genetic admixture in human, the result of inter-marriage among people from different well-differentiated populations, has been extensively studied in the New World, where European colonization brought contact between peoples of Europe, Africa, and Asia and the Amerindian populations. In Asia, genetic admixing has been also prevalent among previously separated human populations. However, studies on admixed populations in Asia have been largely underrepresented in similar efforts in the New World. Here, I will provide an overview of population genomic studies that have been published to date on human admixture in Asia, focusing on population structure and population history.

Genetic Structure in Wild Populations of Ayu Plecoglossus altivelis in Korea and Japan

  • Han, Hyon-Sob;Taniguchi, Nobuhiko;Lee, Jong-Ha;Yoon, Moon-Geun
    • Fisheries and Aquatic Sciences
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    • v.14 no.4
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    • pp.295-301
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    • 2011
  • We investigated the genetic structure of Korean and Japanese ayu Plecoglossus altivelis populations by examining 669 individuals from 14 populations using three microsatellite loci. Genetic variation did not differ significantly among the populations examined in terms of allelic number and heterozygosity. Korean populations were genetically close to each other, implying that persistent gene flow has occurred in these populations. This suggests that eastern populations in Korea form a single large population and all of the Korean populations are distinct from the Japanese populations. Pairwise population $F_{ST}$ estimates, principal component analyses, and a neighbor-joining tree showed that genetic separation between the southern and pooled eastern coast populations was probably influenced by restricted gene flow. Hierarchical analysis of molecular variance (AMOVA) revealed a weak but significant genetic structure among three ayu groups (eastern and southern coasts of Korea and the Japan coast), and no genetic variation within groups. The estimated genetic population structure and potential applications of microsatellite markers may aid in the proper management of ayu populations.

Comparison of Population Genetic Structure of Two Seashore-Dwelling Animal Species, Periwinkle Littorina brevicula and Acorn Barnacle Fistulobalanus albicostatus from Korea

  • Kim, Yuhyun;Lee, Jeounghee;Kim, Hanna;Jung, Jongwoo
    • Animal Systematics, Evolution and Diversity
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    • v.32 no.2
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    • pp.105-111
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    • 2016
  • The genetic structure of marine animals that inhabit the seashore is affected by numerous factors. Of these, gene flow and natural selection during recruitment have strong influences on the genetic structure of seashore-dwelling species that have larval periods. Relative contributions of these two factors to the genetic structure of marine species would be determined mainly by the duration of larval stage. The relationship between larval period and genetic structure of population has been rarely studied in Korea. In this study, genetic variations of cytochrome oxidase subunit I (COI) were analyzed in two dominant species on rocky shore habitats in the Korean peninsula: periwinkle Littorina brevicula and acorn barnacle Fistulobalanus albicostatus. Both species are not strongly structured and may have experienced recent population expansion. Unlike periwinkle, however, barnacle populations have considerable genetic variation, and show a bimodal pattern of mismatch distribution. These results suggest that barnacle populations are more affected by local adaptation rather than gene flow via larval migration. The bimodal patterns of barnacle populations observed in mismatch distribution plots imply that they may have experienced secondary contact. Further studies on seashore-dwelling species are expected to be useful in understanding the evolution of the coastal ecosystem around Korean waters.