• ALGAE
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• 제33권3호
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• pp.269-278
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• 2018

Ocean warming can have significant negative impacts on population genetic diversity, local endemism and geographical distribution of a wide range of marine organisms. Thus, the identification of conservation units with high risk of extinction becomes an imperative task to assess, monitor, and manage marine biodiversity for policy-makers. Here, we surveyed population structure and genetic variation of the red seaweed Gracilaria vermiculophylla along the coast of China using genome-based amplified fragment length polymorphism (AFLP) scanning. Regardless of analysis methods used, AFLP consistently revealed a south to north genetic isolation. Populations at the southern coast of China showed unique genetic variation and much greater allelic richness, heterozygosity, and average genetic diversity than the northern. In particular, we identified a geographical barrier that may hinder genetic exchange between the two lineages. Consequently, the characterized genetic lineage at the southern coast of China likely resulted from the interplay of post-glacial persistence of ancestral diversity, geographical isolation and local adaptation. In particular, the southern populations are indispensable components to explore evolutionary genetics and historical biogeography of G. vermiculophylla in the northwestern Pacific, and the unique diversity also has important conservation value in terms of projected climate warming.

• The Plant Pathology Journal
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• 제37권5호
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• pp.476-488
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• 2021

Xanthomonas campestris pv. campestris (Xcc) is the causal agent of black rot for cruciferous vegetables worldwide, especially for the cole crops such as cabbage and cauliflower. Due to the lack of resistant cabbage cultivars, black rot has brought about considerable yield losses in recent years in China. Understanding of the pathogen features is a key step for disease prevention, however, the pathogen diversity, population structure, and virulence are largely unknown. In this study, we studied 50 Xcc strains including 39 Xcc isolates collected from cabbage in 20 regions across China, using multilocus sequence genotyping (MLST), repetitive DNA sequence-based PCR (rep-PCR), and pathogenicity tests. For MLST analysis, a total of 12 allelic profiles (AP) were generated, among which the largest AP was AP1 containing 32 strains. Further cluster analysis of rep-PCR divided all strains into 14 DNA groups, with the largest group DNA I comprising of 34 strains, most of which also belonged to AP1. Inoculation tests showed that the representative Xcc strains collected from diverse regions performed differential virulence against three brassica hosts compared with races 1 and 4. Interestingly, these results indicated that AP1/DNA I was not only the main pathotype in China, but also a novel group that differed from the previously reported type races in both genotype and virulence. To our knowledge, this is the first extensive genetic diversity survey for Xcc strains in China, which provides evidence for cabbage resistance breeding and opens the gate for further cabbage-Xcc interaction studies.

• Animal Systematics, Evolution and Diversity
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• 제13권3호
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• pp.233-246
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• 1997

남한의 15개 지역에서 채집된 재첩속(Corbicula) 4종간의 유전적 분화수준 및 계통 유연관계를 규명하고자 전기영동을 이용한 동위효소 분석을 실시하였다. 이들 4종 중 담수 산인 C. fluminea, C. leana, C. colorata 3종의 종내 집단간 유전적 근연치는 S=0.970 이상 (0.970∼1.000)으로 매우 가깝게 나타났으나 기수산인 C. japonica의 집단들은 Gp-1 유전자 에서 뚜렷한 대립인자 차이를 가지는 2개의 유전적 group으로 분리(S=0.873)되어 이에 대한 추가적인 분류학적 검토가 요구되었다. 각 종간의 유전적 근연치는 C. fluninea와 C. leana 가 S=0.689, C. fluminea와 C. colorata는 S=0.594 그리고 C. leana와 C. colorata는 S=0.737 로 나타나 이들 담수산 3종간의 유전적 차이는 매우 뚜렷하였다. 특히, 기수산인 C. japonica는 담수산 3종과의 평균 유전적 근연치가 S=0.370으로 가장 먼 유전적 근연관계를 나타내었다.

• Asian-Australasian Journal of Animal Sciences
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• 제25권2호
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• pp.177-182
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• 2012

To investigate the genetic diversity of seven Chinese indigenous meat goat breeds (Tibet goat, Guizhou white goat, Shannan white goat, Yichang white goat, Matou goat, Changjiangsanjiaozhou white goat and Anhui white goat), explain their genetic relationship and assess their integrity and degree of admixture, 302 individuals from these breeds and 42 Boer goats introduced from Africa as reference samples were genotyped for 11 microsatellite markers. Results indicated that the genetic diversity of Chinese indigenous meat goats was rich. The mean heterozygosity and the mean allelic richness (AR) for the 8 goat breeds varied from 0.697 to 0.738 and 6.21 to 7.35, respectively. Structure analysis showed that Tibet goat breed was genetically distinct and was the first to separate and the other Chinese goats were then divided into two sub-clusters: Shannan white goat and Yichang white goat in one cluster; and Guizhou white goat, Matou goat, Changjiangsanjiaozhou white goat and Anhui white goat in the other cluster. This grouping pattern was further supported by clustering analysis and Principal component analysis. These results may provide a scientific basis for the characteristization, conservation and utilization of Chinese meat goats.

• Asian-Australasian Journal of Animal Sciences
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• 제32권10호
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• pp.1501-1510
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• 2019

Objective: An experiment was conducted to evaluate genetic diversity of 26 Chinese indigenous goats by 30 microsatellite markers, and then to define conservation priorities to set up the protection programs according to the weight given to within- and between-breed genetic diversity. Methods: Twenty-six representative populations of Chinese indigenous goats, 1,351 total, were sampled from different geographic regions of China. Within-breed genetic diversity and marker polymorphism were estimated calculating the mean number of alleles, observed heterozygosities, expected heterozygosities, fixation index, effective number of alleles and allelic richness. Conservation priorities were analyzed by statistical methods. Results: A relatively high level of genetic diversity was found in twenty-four population; the exceptions were in the Daiyun and Fuqing goat populations. Within-breed kinship coefficient matrices identified seven highly inbred breeds which should be of concern. Of these, six breeds receive a negative contribution to heterozygosity when the method was based on proportional contribution to heterozygosity. Based on Weitzman or Piyasatian and Kinghorn methods, the breeds distant from others i.e. Inner Mongolia Cashmere goat, Chengdu Brown goat and Leizhou goat obtain a high ranking. Evidence from Caballero and Toro and Fabuel et al method prioritized Jining Gray goat, Liaoning Cashmere goat, and Inner Mongolia Cashmere goat, which agree with results from Kinship-based methods. Conclusion: Conservation priorities were determined according to multiple methods. Our results suggest Inner Mongolia Cashmere goat (most methods), Jining Gray goat and Liaoning Cashmere goat (high contribution to heterozygosity and total diversity) should be prioritized based on most methods. Furthermore, Daiyun goat and Shannan White goat also should be prioritized based on consideration of effective population size. However, if one breed can continually survive under changing conditions, the straightforward approach would be to increase its utilization and attraction for production via mining breed germplasm characteristics.

• 한국자원식물학회:학술대회논문집
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• 한국자원식물학회 2020년도 춘계학술대회
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• pp.47-47
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• 2020

The Korean National Agrobiodiversity Center holds the more than 1300 accessions of proso millet, but a large portion of accessions are landrace of Korea that has very similar traits. To comprehend the maximum genetic diversity of this crop, a core collection with minimum number of accessions will facilitate easy access to genetic material. Here we assessed the genetic diversity and population structure in a germplasm collection of 830 accessions by employing EST-SSR markers and morphological traits. A total of 107 alleles were detected with an average allele number of 4.9 per locus among the 830 accessions based on 37 EST-SSR markers. The number of alleles per locus ranged from 2 to 7. Polymorphism information content and expected heterozygosity ranged from 0.06 to 0.68 (mean = 0.21) and 0.06 to 0.73 (mean = 0.23), respectively. The germplasm collection was separated into two groups based on population structure analysis, whereas principal coordinate analysis (PCoA) could not cluster accessions according to their geographic origin. Subsequently, a preliminarily developed core collection with a total of 141 accessions (17%) was selected from the whole set of germplasm by combining allelic variations of EST-SSR markers and eight different phenotypic traits. The core collection optimally represented the whole germplasm collection and displayed a similar level of PCoA value and genetic variation from the initial collection. The results obtained here provide a primary resource for further genetic analysis and establish a reference for further development of appropriate genetic breeding strategies.

• Journal of Plant Biotechnology
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• 제39권1호
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• pp.62-68
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• 2012

The vegetable brassicas are an important crop worldwide and are of significant commercial value. In order to ensure our targets for food security are met it is important that these crops are continually improved to increase sustainability of production, increase nutritional quality and reduce waste. Development of resistances against both biotic and abiotic stress are recognised as being key. Plant breeding plays a vital role in addressing these issues through the development of new and improved varieties. This continued improvement is becoming evermore dependent on our ability to identify and introgress beneficial alleles from 'exotic' germplasm into elite breeding material. Increasingly, more diverse germplasm such as those found in genebanks is being screened for benificial allelic variation, however, plant breeders often find it difficult to make use of such material due to the time required to remove undesirable characteristics from progeny due to linkage drag. This article describes how we have attempted to overcome this and develop resources that make the diversity available within the $Brassica$ $oleracea$ genepool more accessible.

• Journal of Oral Medicine and Pain
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• 제22권2호
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• pp.253-260
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• 1997

한국인 집단에서 개인식별의 기초자료로 활용하고자 한국인 201명을 대상으로 STR 유전좌위 중 하나인 LPL 유전좌위의 유전자 빈도 및 유전자형 분포를 구하였다. 혈액으로부터 추출한 핵 DNA를 중합효소연쇄반응으로 증폭시키고 폴리아크릴아마이드 겔 상에서 전기영동하여 은염색한 후 관찰하여 다음의 결과를 얻었다. 1. 한국인 집단 201명의 LPL 유전자에서 5개의 대립유전자, 7개의 유전자형을 검출하였으며, 이형접합도는 50.7%로 나타났고 대립 유전자다양성 (allelic diversity value)은 0.454, 개 인식 별력 (PD)은 0.674를 보였다. 2. 대립 유전자 및 유전자빈도는 9, 10, 11, 12, 13 대립 유전자에서 각각 0.020, 0.714, 0.100, 0.164, 0.002로 나타났으며, 대립유전자 7, 8, 14는 관찰되지 않았다. 이상의 결과를 볼 때 한국인 집단에서 STR LPL유전좌위의 유전자빈도는 친자감정 등 개인식별에 유용하게 사용할 수 있으나 감정실무에 응용시 다수의 STR유전좌위 및 VNTR유전좌위의 분석을 병행하여야 할 것으로 사료된다.

• Genomics & Informatics
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• 제6권1호
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• pp.14-17
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• 2008

GENDISCAN study (Gene Discovery for Complex traits in Asian population of Northeast area) was designed to incorporate methodologies which enhance the power to identify genetic variations underlying complex disorders. Use of population isolates as the target population is a unique feather of this study. However, population isolates may have hidden inbreeding structures which can affect the validity of the study. To understand how this issue may affect results of GENDISCAN, we estimated inbreeding coefficients in two study populations in Mongolia. We analyzed the status of Hardy-Weinberg Equilibrium (HWE), polymorphism information contents (PIC), heterozygosity, allelic diversity, and inbreeding coefficients, using 317 and 1,044 STR (short tandem repeat) markers in Orkhontuul and Dashbalbar populations. HWE assumptions were generally met in most markers (88.6% and 94.2% respectively), and single marker PIC ranged between 0.2 and 0.9. Inbreeding coefficients were estimated to be 0.0023 and 0.0021, which are small enough to assure that conventional genetic analysis would work without any specific modification. We concluded that the population isolates used in GENDISCAN study would not present significant inflation of type I errors from inbreeding effects in its gene discovery analysis.

• Animal cells and systems
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• 제2권2호
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• pp.281-285
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• 1998

We examined Y chromosomal DNA polymorphisms at the DYS19 and DXYS5Y loci in a total of 480 unrelated male samples from the Korean population. All five common alleles were identified at the tetranucleotide microsatellite locus DYS19 in this study. The C allele was the most frequent (212/480), followed by D (136/480), B (75/480), E (36/480) and A (21/480) allele. The frequency of Y2 allele at the DXYS5Y locus was found to be 4.6% (22/480). Combining the allelic variation at these two loci resulted in a total of 9 combination haplotypes. The mean combination haplotype diversity wIns 0.72. Based on the results of these two loci, Korean and Japanese populations may share some common genetic structure that is rare or absent in the other ethnic groups. The genetic similarity between Korean and Japanese populations may be due to the large infusion of Y chromosomes through the Yayoi migration starting 2,300 years ago from Korea to Japan.