• Title/Summary/Keyword: Genetic variation

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Evaluation of Genetic Heterogeniety among the Corn Landraces Collected from Farmer's Field

  • Kim, In-Jong;Min, Hwang-Kee;Park, Jong-Yeol;Choi, Ik-Young;Kim, Nam-Soo
    • Plant Resources
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    • v.1 no.1
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    • pp.26-32
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    • 1998
  • This paper describes the variations in eight agronomic traits in three unadapted local landraces and an inbred cultivar of corn. To compare the agronomic traits in field evaluation with molecular marker evaluation the genotypes of the plant introduction were also checked by 4 microsatellite-SSR loci. The variations of the eight agronomic traits were higher in the local landrades than in the inbred line. which was substantiated by the high genetic variation in the landrades with microsatellite-SSR loci. The level of genetic variation was also different between landraces. Since the genetic evaluation can be easily quantified by the analysis of microsatellite-SSR loci. the threshold level of genetic homogeneity in the population for parental lines in breeding program can be determined and the effort of maintaining the landrace population would be alleviated. As an example in our analysis. the entry from Whachon should not need the same number of selfing generations as the other two landraces to get the level of inbred state. Since this line showed lowest intra-genetic variation within the population.

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Comparison of Genetic Diversity and Population Structure of Kalopanax pictus (Araliaceae) and its Thornless Variant Using RAPD

  • Huh, Man-Kyu;Jung, Sang-Duk;Moon, Heung-Kyu;Kim, Sea-Hyun;Sung, Jung-Sook
    • Korean Journal of Medicinal Crop Science
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    • v.13 no.2
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    • pp.69-74
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    • 2005
  • Kalopanax pictus is a long-lived woody species mostly distributed in East Asia. K. pictus has been regarded as medically and ecologically important species in Korea. Thornless castor aralia variant, local name 'Cheongsong' is an endemic to Cheongsong province in Korea. Random amplified polymorphic DNA (RAPD) was used to investigate the genetic variation and structure of Korean populations of two species. A high level of genetic variation was found in six K. pictus populations. Twelve primers revealed 49 loci, of which 29 were polymorphic (59.2%). Nei's gene diversity for K.pictus and K. pictus variant were 0.119 and 0.098, respectively. Mean of genetic diversity in K. pictus was higher than average values for species with similar life history traits. The asexual and sexual reproduction, perennial habitat, and longevity are proposed as possible factors contributing to high genetic diversity. An indirect estimate of the number of migrants per generation (Nm=0.857) indicated that gene flow was not extensive among Korean populations of K.pictus. It is suggested that the isolation of geographical distance and reproductive isolation between K.pictus and K.pictus variant populations may have played roles in shaping the population structure of this species.

Discrepancies between Mitochondrial DNA and AFLP Genetic Variation among Lineages of Sea Slaters Ligia in the East Asian Region

  • Kang, Seunghyun;Jung, Jongwoo
    • Animal Systematics, Evolution and Diversity
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    • v.36 no.4
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    • pp.347-353
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    • 2020
  • Although sea slaters Ligia have a significant role in rocky shore habitats, their taxonomic entities have not been clearly understood. In this study, we investigated whether genetic variation inferred from a nuclear genetic marker, namely amplified fragment length polymorphism (AFLP), would conform to that of a mitochondrial DNA marker. Using both the mitochondrial DNA marker and the AFLP marker amplified by the six selective primer sets, we analyzed 95 Ligia individuals from eight locations from East Asia. The direct sequencing of mitochondrial 16S rRNA gene revealed three distinct genetic lineages, with 9.8-11.7 Kimura 2-parameter genetic distance. However, the results of AFLP genotyping analysis with 691 loci did not support those of mitochondrial DNA, and revealed an unexpectedly high proportion of shared polymorphisms among lineages. The inconsistency between the two different genetic markers may be explained by difference in DNA evolutionary history, for example inheritance patterns, effective population size, and mutation rate. The other factor is a possible genomic island of speciation, in that most of the genomic parts are shared among lineages, and only a few genomic regions have diverged.

Evaluation of Genetic Variation and Phylogenetic Relationship among North Indian Cattle Breeds

  • Sharma, Rekha;Pandey, A.K.;Singh, Y.;Prakash, B.;Mishra, B.P.;Kathiravan, P.;Singh, P.K.;Singh, G.
    • Asian-Australasian Journal of Animal Sciences
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    • v.22 no.1
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    • pp.13-19
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    • 2009
  • In the present study, genetic analyses of diversity and differentiation were performed on four breeds of Indian zebu cattle (Bos indicus). In total, 181 animals belonging to Ponwar, Kherigarh, Gangatiri and Kenkatha breeds were genotyped for 20 cattle specific microsatellite markers. Mean number of alleles observed per locus (MNA) varied between 5.75 (Kenkatha) to 6.05 (Kherigarh). The observed and expected heterozygosity for the breeds varied from 0.48 (Gangatiri) to 0.58 (Kherigarh) and 0.65 (Kenkatha) to 0.70 (Kherigarh), respectively. $F_{IS}$ estimates of all the breeds indicated significant deficit of heterozygotes being 28.8%, 25.9%, 17.7% and 17.7% for Gangatiri, Ponwar, Kherigarh and Kenkatha, respectively. The $F_{ST}$ estimates demonstrated that 10.6% was the average genetic differentiation among the breeds. Nei's genetic distance DA and Cavalli- Sforza and Edwards Chord distance ($D_C$) and the phylogenetic tree constructed from these reflected the close genetic relationship of Gangatiri and Kenkatha, whereas Ponwar appears to be more distant.

Population Structure and Genetic Bottleneck Analysis of Ankleshwar Poultry Breed by Microsatellite Markers

  • Pandey, A.K.;Kumar, Dinesh;Sharma, Rekha;Sharma, Uma;Vijh, R.K.;Ahlawat, S.P.S.
    • Asian-Australasian Journal of Animal Sciences
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    • v.18 no.7
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    • pp.915-921
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    • 2005
  • Genetic variation at 25 microsatellite loci, population structure, and genetic bottleneck hypothesis were examined for Ankleshwar poultry population found in Gujrat, India. The estimates of genetic variability such as effective number of alleles and gene diversities revealed substantial genetic variation frequently displayed by microsatellite markers. The average polymorphism across the studied loci and the expected gene diversity in the population were 6.44 and 0.670${\pm}$0.144, respectively. The population was observed to be significantly differentiated into different groups, and showed fairly high level of inbreeding (f = 0.240${\pm}$0.052) and global heterozygote deficit. The bottleneck analysis indicated the absence of genetic bottleneck in the past. The study revealed that the Ankleshwar poultry breed needs appropriate genetic management for its conservation and improvement. The information generated in this study may further be utilized for studying differentiation and relationships among different Indian poultry breeds.

Genetic Studies of Oenothera odorata Populations in Korea Based on Isozyme Analysis

  • Huh, Hong-Wook
    • Journal of Plant Biology
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    • v.39 no.3
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    • pp.223-229
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    • 1996
  • The genetic variation in Korean evening primorse (Oeothera odorata L.) populations was examiend to estimate the level of allozyme variation within populatons using starch gel electrophoresis. 7 of 13 loci (Adh, Est-1, Est-2, Mdh-2, Pgd-2, Pgm-1, and Idh) revealed (Ps=43.2%) were polymorphic. The mean number of alleles per locus (A) and polymorphic locus (Ap) for populations were 1.64 and 2.46, respectively. The effective number of alleles (Aep) within populations relatively was low ranging from 1.08 to 1.22 with a mean of 1.14. Within populations, the mean number of allele per polymorphic loci (Ap) was 2.46, the mean number of alleles per locus (A) was 1.64, and the mean genetic diversity was 0.093. About 2.7% of the total allozyme diversity resided among populations (Mean GST=0.0274). FIS, a measure of the deviation from random mating within 13 populations, was relative low (mean FIS=0.03636). The indirect estimate of gene flow, based on the mean GST, was high (Nm=8.88). Estimates of gene flow were consistent with low levels of genetic differentiation among populations.

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RAPD Variation and Phenetic Relationships for Six Populations of Equisetum pratense in Korea (한국 내 물쇠뜨기 6개 집단의 RAPD 변이와 표현형 관계)

  • Huh, Man Kyu;Choi, Jaewon;Lee, Jangseop;Jin, Bogye;Kim, Hyun Kyung
    • Journal of Life Science
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    • v.24 no.6
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    • pp.612-617
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    • 2014
  • The phenetic relationships among six natural populations of Equisetum pratense in Korea were investigated at the population level by constructing a tree based on Random Amplified Polymorphic DNA (RAPD) markers. RAPD analysis was also conducted to estimate genetic diversity and the population structure of E. pratense. A mean of 26.7% at the six population levels indicated polymorphism. E. pratense was found to have fewer alleles per locus (1.267) and fewer effective alleles per locus (1.176). Genetic diversity (0.102) in E. pratense is lower than the average for species with similar life history traits. Total genetic diversity values (HT) varied between 0.112 (OPD-07) and 0.445 (OPD-16), for an average overall polymorphic locus of 0.141. Inter-locus variation in the within-population genetic diversity ($H_S$) was low (0.102). Asexual reproduction, small population size, and the colonization process are proposed as possible factors contributing to the observed low genetic diversity in E. pratense. On a per-locus basis, the proportion of total genetic variation due to differences among populations ($G_{ST}$) ranged from 0.129 for OPD-07 to 0.455 for OPD-09, with a mean of 0.277. This indicated that about 27.7% of the total variation was among populations. Thus, genetic variation (72.3%) resided within populations. This study contributes new information for research on the taxonomy and population genetics of E. pratense.

RAPD Polymorphism of Xanthoceras sorbifolium Bunge from Three Plantations of China (중국 3곳 문관나무 재배집단의 RAPD 다형성)

  • An, Chanhoon;Lee, Hyunseok;Yin, Zhiyang;Yi, Jae-Seon
    • Journal of Forest and Environmental Science
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    • v.28 no.4
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    • pp.242-246
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    • 2012
  • The variation in random amplified polymorphic DNA (RAPD) markers were examined for Xanthoceras sorbifolium Bunge seeds from three plantations (Inner Mongolia [IM], Liaoning [LN], and Shandong [SD] province) in China. Mean genetic variation was measured by polymorphism percentage (42.10%) and expected heterozygosity (He=1.27). Among three populations, Shandong showed the highest values both in polymorphism percentage and heterozygosity (p=57.89; Ho=1.58; and He=1.37). Total genetic diversity value, based on the total loci, was estimated as total genetic diversity of the species (Ht)=0.27 and mean within-population genetic diversity (Hs)=0.16. UPGMA cluster analysis showed the genetic closeness between Inner Mongolia and Liaoning population, but that Shandong seems to be the separate population.

Genetic Diversity in Korean Populations of Glycine soja (Fabaceae)

  • Myong Gi Chung
    • Journal of Plant Biology
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    • v.38 no.1
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    • pp.39-45
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    • 1995
  • Glycine soja Sieb. et Zucc., a predominantly selfing annual, has been served as a reservoir of germplasm for soybean, G. max (L.) Merr., cultivar improvement. This study describes the levels and distribution of genetic variation within and among 22 Korean populations of G. soja using starch gel electrophoresis. The species maintains very similar levels of genetic variability within populations observed in most other annuals. At the population level, the mean percent of polymorphic loci (P) was 32.6%, mean number of allele per locus (A) was 1.32, and mean expected heterozygosity (He) was 0.112. In addition, total genetic diversity (HT) calculated only for polymorphic loci was 0.347. However, significant differences in allele frequencies among populations were found for all loci (P<0.001 in each case) and, on average, about 70% of the total variation in the species is common to all populations. Indirects estimate of the number of migrants per generation (Nm=0.58, calculated from mean GST) indicates that gene flow is low among Korean populations of the species. In addition, analysis of fixation indices revealed a substantial heterozygote deficiency in most populations and at all loci. This indicates that most populations sampled may have been substructed largely due to inbreeding (predominantly selfing) and restricted gene flow, coupled with founder effect and genetic drift. Considering a high genetic divergence among populations, it is recommended that several Korean populations of the species should be preserved, especially such as populations in the eastern and southeastern Korean peninsula with high variation.

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Genetic Variation in the Asian Shore Crab Hemigrapsus sanguineus in Korean Coastal Waters as Inferred from Mitochondrial DNA Sequences

  • Hong, Sung-Eic;Kim, Jin-Koo;Yu, Jeong-Nam;Kim, Keun-Yong;Lee, Chung-Il;Hong, Kwan-Eui;Park, Kie-Young;Yoon, Moon-Geun
    • Fisheries and Aquatic Sciences
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    • v.15 no.1
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    • pp.49-56
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    • 2012
  • Genetic variation in the Asian shore crab Hemigrapsus sanguineus was determined from partial mitochondrial DNA (mtDNA) sequences of the cytochrome b (Cytb) gene. Samples included 143 crabs from six localities along three coastlines in South Korea. A nucleotide sequence analysis revealed 38 variable sites in a 470-bp sequence, which defined 37 haplotypes. The haplotypes were not associated geographically and had a shallow genealogy. Pairwise $F_{ST}$ tests and a two-dimensional scaling analysis revealed no significant genetic differentiation among most of the populations. The low pairwise comparison values, but significant genetic differentiation of a northeastern population from all other populations, might have been influenced by a restriction in gene flow caused by hydrographic conditions such as ocean boundaries. The high haplotype diversity, low nucleotide diversity, and time since H. sanguineus expansion in Korean coastal waters indicate rapid population growth and a recent, sudden expansion in the Late Pleistocene.