• 제목/요약/키워드: Gene diversity

검색결과 945건 처리시간 0.027초

Bacterial Diversity at Different Depths in Lead-Zinc Mine Tailings as Revealed by 16S rRNA Gene Libraries

  • Zhang, Han-Bo;Shi, Wen;Yang, Ming-Xia;Sha, Tao;Zhao, Zhi-Wei
    • Journal of Microbiology
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    • 제45권6호
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    • pp.479-484
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    • 2007
  • Bacterial communities at 10 cm, 100 cm, and 200 cm depths in a 100-year-old lead-zinc tailing heap were evaluated by constructing 16S rRNA gene libraries. In total, 98 operational taxonomic units (OTUs) were identified from 193 clones at a 3% sequence difference level. The OTU number and species richness decreased with the depth. Species composition was significantly different between the three libraries. Fifty-seven percent of the examined clones were Acidobacteria and 27% belonged to Proteobacteria. Other sequences included Chloroflexi, Firmicutes, Chlamydiae, Actinobacteria, Gemmatimonadetes, Nitrospira, and three unclassified OTUs. Alphaproteobacteria, Betaproteobacteria, Gammaproteobacteria, Firmicutes, and Actinobacteria were mainly distributed in the rhizosphere of naturally colonizing plants; however, Deltaproteobacteria, Acidobacteria, and Chloroflexi tended to inhabit the deeper tailings (below the 100 cm-depth).

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

  • Huh, Hong-Wook
    • Journal of Plant Biology
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    • 제39권3호
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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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Genetic Diversity and Population Structure of maize, Zea mays, in Both Landraces and Cultivar Lines

  • Huh, Man-Kyu;Lee, In-Sup
    • Journal of Life Science
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    • 제12권1호
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    • pp.27-32
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    • 2002
  • Enzyme electrophoresis was used to estimate genetic diversity and population structure of maize, Zea mays L. (Graminales) in Korea. In nine populations, fourteen of the 24 loci (58.3 %) showed detectable polymorphism. Genetic diversity (0.205) was higher than average values for species with similar life history traits. Although our data are relatively small and the landraces not direct ancestors of cultivar, apparently the domestication process has eroded the levels of genetic variation of maize. The recent cultivars were found to have fewer alleles per locus (1.42 vs. 1.56), fewer alleles per polymorphic locus (2.27 vs. 2.33), lower percent polymorphic locus (33.3% vs. 41.7%), and lower diversity (0.159 vs. 0.185) than landraces. These genetic diversity parameters indicated that the cultivar populations were genetically depauperate relative to landlaces. The GST value of nine populations was 0.239. Nearly 76% of the total genetic diversity in Zea mays was apportioned within populations. The indirect estimate of gene new based on mean GST was moderate (Nm=0.80).

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Monitoring conservation effects on a Chinese indigenous chicken breed using major histocompatibility complex B-G gene and DNA Barcodes

  • Tu, Yunjie;Shu, Jingting;Ji, Gaige;Zhang, Ming;Zou, Jianmin
    • Asian-Australasian Journal of Animal Sciences
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    • 제31권10호
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    • pp.1558-1564
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    • 2018
  • Objective: We report monitoring conservation effect for a Chinese indigenous chicken (Langshan) breed using major histocompatibility complex (MHC) and DNA barcords. Methods: The full length of MHC B-G gene and mitochondrial cytochrome oxidase I (COI) gene in generations 0, 5, 10, 15, 16, and 17 was measured using re-sequencing and sequencing procedures, respectively. Results: There were 292 single nucleotide polymorphisms of MHC B-G gene identified in six generations. Heterozygosity (He) and polymorphic information content (PIC) of MHC B-G gene in generations 10, 15, 16, and 17 remained stable. He and PIC of MHC B-G gene were different in six generations, with G10, G15, G16, G17 >G5>G0 (p<0.05). For the COI gene, there were five haplotypes in generations 0, 5, 10, 15, 16, and 17. Where Hap2 and Hap4 were the shared haplotypes, 164 individuals shared Hap2 haplotypes, while Hap1 and Hap3 were the shared haplotypes in generations 0 and 5 and Hap5 was a shared haplotype in generations 10, 15, 16, and 17. The sequence of COI gene in 6 generations was tested by Tajima's and D value, and the results were not significant, which were consistent with neutral mutation. There were no differences in generations 10, 15, 16, and 17for measured phenotypic traits. In other generations, for annual egg production, with G5, G10, G15, G16, G17>G0 (p<0.05). For age at the first egg and age at sexual maturity, with G10, G15, G16, G17>G5>G0 (p<0.05). Conclusion: Combined with the results of COI gene DNA barcodes, MHC B-G gene, and phenotypic traits we can see that genetic diversity remained stable from generations 10 to 17 and the equimultiple random matching pedigrees conservation population conservation effect of Langshan chicken was effective as measured by these criteria.

동아시아 질경이 집단의 유전적 다양성과 집단구조 (Genetic Diversity and Population Structure in East Asian Populations of Plantago asiatica)

  • 허만규
    • 생명과학회지
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    • 제23권6호
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    • pp.728-735
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    • 2013
  • 질경이(Plantago asiatica)는 주로 동아시아에 분포하는 풍매화 식물이다. 전분 젤 전기영동으로 이 종의 18개 집단에 대한 알로자임 다양성과 집단구조를 평가하였다. 비록 질경이 집단은 작고 격리되어 있지만, 높은 유전적 다양성을 가지고 있었다. 평균 다형성을 나타내는 유전자좌위의 수는 57.1%였고, 대립유전자좌위당 유전자수는 2.07이였으며, 18개 집단에 대한 이형접합성은 0.201이였다. 풍매화, 혼합적 생식교배계, 큰 집단 크기, 집단 간 높은 유전자 이동, 다산의 특성이 집단 내 유전적 다양성을 설명할 수 있다. 유전적 다양성은 위도와 관련이 있었는데 질경이 집단은 북위 $35^{\circ}3^{\prime}$를 초과하면 유전적 다양성은 현저하게 감소하였다. 반면에 유전적 다양성에 대한 경도 구배는 나타나지 않았다.

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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    • 제10권1호
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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 Diversity of mtDNA D-loop Polymorphisms in Laotian Native Fowl Populations

  • Kawabe, K.;Worawut, R.;Taura, S.;Shimogiri, T.;Nishida, T.;Okamoto, S.
    • Asian-Australasian Journal of Animal Sciences
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    • 제27권1호
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    • pp.19-23
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    • 2014
  • Here, we studied the genetic diversity of native fowls in Laos by analyzing a mitochondrial DNA (mtDNA) sequence polymorphism. A 546-bp fragment of the mtDNA D-loop region was sequenced in 129 chickens from the areas of Vientiane, Luang Prabang and Pakse. In total, 29 haplotypes were identified and formed five clades. Haplotype diversity and nucleotide diversity of the native fowls in Laos were $0.85536{\pm}0.0172$ and $0.010158{\pm}0.005555$, respectively. Although the Laotian native fowls were distributed across five clades, most of them were clustered in two main clades (A and B), which were originated in China. The other haplotypes were contained in clades D, F, and I, which originated from continental southeast Asia. These results suggest that multiple maternal lineages were involved in the origin of domestic chicken in Laos. Moreover, there appear to be at least two maternal lineages, one from China and the other from the southeast Asian continent.

Allozyme Diversity and Population Genetic Structure in Korean Endemic Plant Species : II. Hosta yingeri (Liliaceae)

  • Chung, Myong Gi
    • Journal of Plant Biology
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    • 제37권2호
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    • pp.141-149
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    • 1994
  • Levels of genetic diversity, population genetic structure, and gene flow in Hosta yingeri, a herbaceous perennial endemic to Taehuksan, Sohuksan, and Hong Islands, were investigated. Starch gel electrophoresis was conducted on leaves for 101 plants collected from three populations. Although the distribution of thespecies is restricted in the islands, it maintains high levels of genetic variatin; 64% of polymorphic loci in at least one population (Ps), the mean number of alleles per locus (Ap) of 1.92, and the mean effective number of alleles per locus (Aep) of 1.52. Overall, mean genetic diversity (Hep=0.250) was substantially higher than mean estimate for species with very similarlife history traits (0.102). Large populaton size, the persistence of multiple generations within populations, high fecundity, predominantly outcrossing breeding system, large size of pollinator visitation areas may be explanatory factors contributing the higher level of genetic diversity maintained within populations. Analysis of fixation indices showed an overall slight excess of heterozygotes (mean FIS=-0.066) relative to Hardy-Weinberg expectations, which may in part be due to the near self-incompatible breeding system in the species. Significant differences in allele frequencies among populaitns were found for 14 out of 16 polymorphic loci (P<0.05). Slightly more than 80% of the total variation in the species was common to all populations (GST=0.198). As expected, indirect estimate of the number of migrants per generation (Nm=0.45, calculated from mean GST) and nine private alleles found in the three populations indicate that gene movement among three isolated island populations was low.

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Genetic Diversity of Goats from Korea and China Using Microsatellite Analysis

  • Kim, K.S.;Yeo, J.S.;Lee, J.W.;Kim, J.W.;Choi, C.B.
    • Asian-Australasian Journal of Animal Sciences
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    • 제15권4호
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    • pp.461-465
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    • 2002
  • Nine microsatellite loci were analyzed in 84 random individuals to characterize the genetic variability of three domestic goat breeds found in Korea and China: Korean goat, Chinese goat and Saanen. Allele diversity, heterozygosity, polymorphism information content, F-statistics, indirect estimates of gene flow (Nm) and Nei's standard distances were calculated. Based on the expected mean heterozygosity, the lowest genetic diversity was exhibited in Korean goat ($H_E$=0.381), and the highest in Chinese goat ($H_E$=0.669). After corrections for multiple significance tests, deviations from Hardy-Weinberg equilibrium were statistically significant over all populations and loci, reflecting the deficiencies of heterozygotes (global $F_{IS}$=0.053). Based on pairwise FST and Nm between different breeds, there was a great genetic differentiation between Korean goat and the other two breeds, indicating that these breeds have been genetically subdivided. Similarly, individual clustering based on the proportion of shared alleles showed that Korean goat individuals formed a single cluster separated from the other two goat breeds.

Status of corn diversity in the marginal uplands of sarangani province, the Philippines: implications for conservation and sustainable use

  • Aguilar, Catherine Hazel;Espina, Pamela Grace;Zapico, Florence
    • 한국작물학회:학술대회논문집
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    • 한국작물학회 2017년도 9th Asian Crop Science Association conference
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    • pp.68-68
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    • 2017
  • The status of corn genetic diversity in the uplands of Sarangani in Southern Philippines was investigated using 12 morphological traits subjected to multivariate statistical analyses. Information about traditional farming, post-harvest and storage practices were also elicited especially in relation to losses of traditional varieties, a phenomenon known as genetic erosion. While a handful of farmers still plant traditional corn varieties in the remotest areas, a significant number had already shifted to genetically modified corn. Furthermore, principal component analysis (PCA) reduced the 12 morphological traits into 5 principal components and identified ear length and ear weight to be major contributors to variation. Cluster Analysis, on the other hand, formed two distinct groups but failed to give information about intra-cluster variability among the 32 collected corn accessions. These results warrant that more informative morphological traits and that molecular markers will be used to obtain a better picture of genetic diversity in Sarangani upland corn. Molecular analysis is also needed to establish genetic identities of these cultivars and to detect gene introgression from GM varieties into the gene pool of farmers' corn varieties. These analyses are imperative for the conservation of traditional corn varieties before they disappear in the Sarangani uplands because of shifting priorities of upland farmers.

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