• Animal cells and systems
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• v.3 no.3
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• pp.275-283
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• 1999

Korean R. plancyi occupies a restricted area in western South Korea and shows a relatively low level of genic variability (%P＝15.2, Ho=0.052, He＝0.048). In contrast, R. nigromaculata is broadly distributed in South Korea. The observed low level of variability of R. nigromaculata (%P＝14.3, Ho＝0.042, He＝0.043) is probably due to its recent colonization. Populations of R. nigromaculata exhibited considerable genetic differentiation (F$_{sT}$=0.149) and low level of gene flow (Nm＝1.427) among populations, compared to those of R. Plancyi (F$_{sTF$_{sT}$}$=0.096, Nm＝2.354), which occupies a restricted area. The observed levels of gene flow among populations of R. nigromaculata (Nm＝1.427) over a broad geographic range is relatively higher than other amphibian species. The high level of gene flow is probably the result of the high dispersal abilities of R. nigromaculata. A survey of temporal genic variation of R. nigromaculata showed that there was no significant change on the overall average genetic diversity from 1978 (average He＝0.044) to 1997 (average He＝0.040). Wright's F-statistics also indicated no significant genetic differentiation from 1978 (F$_{sT}$＝0.118) to 1997 (F$_{sT}$＝0.108). This suggests that the environmental change appears to have had little influence on the genetic composition of R. nigromaculata in the study areas during the past 20 years. The low level of temporal variation might be due to the result of high dispersal abilities and wide migration range of this species.

• Journal of Plant Biotechnology
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• v.44 no.3
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• pp.312-319
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• 2017

The need to preserve and use plant genetic resources is widely recognized, and the prospect of dwindling plant genetic diversity, coupled with increased demands on these resources, has made them a topic of global discussion. In the present study, the genetic diversity and population structure of 73 ginseng accessions collected from six regions in China were analyzed using eight simple sequence repeat (SSR) markers. Major allele frequencies ranged between 0.38 ~ 0.78, with a mean allele frequency value of 0.571. The number of alleles discovered ranged from 3 to 10 per accession, with a mean number of 7; 56 alleles were discovered in total. Gene diversity (GD) and polymorphic information content (PIC) values were similar to each other, and they ranged from 0.36 ~ 0.77 (mean 0.588) and 0.33 ~ 0.74 (mean 0.548), respectively. Accessions were divided into three clusters based on their phylogenetic relationships and genetic similarities, and although the populations were similar, they were not classified according to the region. Regional genetic diversity was also similar, with slight differences observed based on the number of accessions per region. It is expected that the findings of the present study can provide basic data for future studies on ginseng genetic diversity and for breeding ginseng cultivars.

• Journal of Life Science
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• v.22 no.11
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• pp.1493-1499
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• 2012

The level of genetic variation and relationships in three native Korean goat populations (Dangjin, Jangsu, and Tongyeong) as well as the populations of a farm were analyzed, based on 30 microsatellite markers. A total of 277 distinct alleles were observed across the four goat populations, and 102 (36.8%) of these alleles were unique to only one population. The mean observed heterozygosity and polymorphism information content were calculated as 0.461~0.651 and 0.462~0.679, respectively. In the NJ tree constructed based on Nei's $D_A$ genetic distance, the four populations represented four distinct groups. However, the genetic distances between each Korean native goat population and the farm population were two times those among the three native Korean breeds. The genetic structure within the three Korean native goat populations was also investigated. Cluster analysis, using the STRUCTURE software, suggested three clusters. The molecular information of genetic diversity and relationships in this study will be useful for the evaluation, conservation, and utilization of native Korean goat breeds as genetic resources.

• Korean Journal of Ichthyology
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• v.32 no.2
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• pp.39-48
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• 2020

The slender shinner (Pseudopungtungia tenuicorpa), a tiny freshwater fish of about 8 to 10 cm belonging to Cyprinidae, is an endangered species found only in the Han and Imjin Rivers on the Korean Peninsula. During the breeding season, this species spawns in nests of Coreoperca herzi, a predator of this species, or small crevices on rocks. This unique reproductive ecology can make this species more vulnerable to anthropogenic perturbance that can further limit the places to spawn. Here, mtDNA and microsatellite loci were analyzed to identify the genetic diversity and structure of slender shinners and further to provide the basic data necessary for the conservation planning of this species. A total of 28 polymorphic microsatellite markers were developed using Illumina paired-end sequencing, and 67 slender shinners collected from three localities in the Han River were genotyped using these loci. This species showed a remarkably high level of genetic diversity with mean expected heterozygosity of 0.914 and mean allele number per locus of 27.9, and no signature of drastic demographic decline was detected. As a result of our microsatellite analysis, the genetic structure between the two stems of the Han River, North Han and South Han, was prominent. Such a genetic structure was also evident in the sequence analysis of 14 haplotypes obtained from mtDNA control region. Although slender shinners are only found in very limited areas around the world, the genetic structure indicates that there is a block of gene flow among the populations, which should be reviewed in the future if management and restoration of this species is needed.

• Plant Biotechnology Reports
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• v.2 no.3
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• pp.191-198
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• 2008

Germplasm characterization and evolutionary process in viable populations are important links between the conservation and utilization of plant genetic resources. Here, an investigation is made, based on molecular and biochemical techniques for assessing and exploiting the genetic variability in germplasm characterization of taro, which would be useful in plant breeding and ex situ conservation of taro plant genetic resources. Geographical differentiation and phylogenetic relationships of Indian taro, Colocasia esculenta (L.) Schott, were analyzed by random amplified polymorphic DNA (RAPD) and isozyme of seven enzyme systems with specific reference to the Muktakeshi accession, which has been to be proved resistant to taro leaf blight caused by P. colocasiae. The significant differentiations in Indian taro cultivars were clearly demonstrated by RAPD and isozyme analysis. RAPD markers showed higher values for genetic differentiation among taro cultivars and lower coefficient of variation than those obtained from isozymes. Genetic differentiation was evident in the taro accessions collected from different regions of India. It appears that when taro cultivation was introduced to a new area, only a small fraction of genetic variability in heterogeneous taro populations was transferred, possibly causing random differentiation among locally adapted taro populations. The selected primers will be useful for future genetic analysis and provide taro breeders with a genetic basis for selection of parents for crop improvement. Polymorphic markers identified in the DNA fingerprinting study will be useful for screening a segregating population, which is being generated in our laboratory aimed at developing a taro genetic linkage map.

• Asian-Australasian Journal of Animal Sciences
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• v.10 no.4
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• pp.428-434
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• 1997

The effect of genetic diversity in sub-populations on breeding efficiency was examined with prospect of potential crossbreeding. Simulation study of selection was performed for 20 generations with 20 replications each, comparing average breeding values and inbreeding coefficients between the two breeding systemes; single population scheme and two population scheme. The different genetic levels were assumed to be caused by different gene frequencies. Phenotypes of two traits generated polygenic effect with additive 36 loci and residuals distributed normally were selected by selection index procedure. High genetic gain with less inbreeding was clearly recognized in the single population scheme, independently of difference in genetic level, economic weight and genetic correlation. Genetic correlation after selection in the single population scheme was lower than the two population scheme. When crossbreeding between the sub-population was taken into account, superiority of the two population scheme was suggested under those restrictions; difference in genetic level is moderate, selection criterion for the two traits is not far from even economic weight, and genetic correlation is positive with low to moderate value. The use of complementarity increased the possibility of the two population scheme.

• Asian-Australasian Journal of Animal Sciences
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• v.15 no.12
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• pp.1822-1830
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• 2002

The microsatellites are the short tandem repeats of 1 to 6 bp long monomer sequences that are repeated several times. These short tandem repeats are considered to be generated by the slipped strand mispairing. Based on the unique capability of alternating purine-pyrimidine residues to form Z-DNA, the possible role of the microsatellites in gene regulation has been proposed. The microsatellites are highly polymorphic, follow Mendelian inheritance and are evenly distributed throughout the genomes of eukaryotes. They are easy to isolate and the polymerase chain reaction based typing of the alleles can be readily automated. These properties make them the preferred markers for comparison of the genetic structure of the closely related breeds/populations; very high-resolution genetic mapping and parentage testing etc. The microsatellites have rapidly replaced the restriction fragment length polymorphism (RFLP) and the random amplified polymorphic DNA (RAPD) in most applications in the population genetics studies in most species, including the various farm animals viz. cattle, buffalo, goat, sheep and pigs etc. More and more reports are now available describing the use of microsatellites in pigs ranging from measurement of genetic variation between breeds/populations, developing high resolution genetic maps to identifying and mapping genes of biological and economic importance.

• Korean Journal of Plant Resources
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• v.26 no.5
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• pp.619-627
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• 2013

Deutzia paniculata Nakai is a Korean endemic species that has a very restricted distribution in Gyeongsang-do, South Korea. The genetic diversity and structure of five populations of D. paniculata were investigated using 31 ISSR loci from six primers. The Shannon's index (0.429) and genetic diversity (0.271) were relatively higher than those of other rare plant species in Korea. The Miryang (MY) and Yangsan (YS) populations, which have higher flowering rates than the other populations, showed greater genetic diversity than the other populations. An analysis of the molecular variance (AMOVA) showed that 16% of the total variation could be attributed to differences among the populations, and 84% to the differences within populations, indicating moderate gene flow among adjacent populations. The high genetic diversity and low genetic differentiation in the Deutzia paniculata populations, which have a restricted distribution, is considered to be affected by outcrossing of the mating system and abundant individuals in the populations. These results suggest that ex situ conservation strategies are needed to sustain the current genetic diversity of D. paniculata.

• Journal of Life Science
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• v.17 no.3 s.83
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• pp.328-333
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• 2007

Genetic diversity and population structure of eleven Liriope platyphylla (Liliaceae) populations in Korea were determined using genetic variation at 20 allozyme loci. The percent of polymorphic loci within the enzymes was 55.9%. Genetic diversity at the species level and at the population level was high(Hes = 0.178; Hep = 0.168, respectively), whereas the extent of the population divergence was relatively low ($G_{ST}$ = 0.064). $F_{IS}$, a measure of the deviation from random mating within the 11 populations, was 0.311. Total genetic diversity values ($H_T$) varied between 0.0 and 0.535, giving an average over all polymorphic loci of 0.323. The interlocus variation in within population genetic diversity ($H_S$) was high (0.305). An indirect estimate of the number of migrants per generation (Nm = 3.66) indicates that gene flow is high among Korean populations of the species. In addition, analysis of fixation indices revealed a substantial heterozygosity deficiency in some populations and at some loci. Mean genetic identity between populations was 0.988. It is highly probable that directional toward genetic uniformity in a relatively the homogenous habitat is thought to be operated among Korean populations of L. platyphylla.

• Proceedings of the Plant Resources Society of Korea Conference
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• 2018.10a
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• pp.43-43
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• 2018

Mutation breeding by radiation is useful for improving various crop species. Up to now, a total of 170 soybean mutant varieties have been released in the world, which is the second most registered varieties after rice. Despite the economic importance of soybean, there have been no TRAP marker system studies on genetic relationships between/among mutant lines. To develop a strategy of Mutant Diversity Pool (MDP) conservation, a study on the genetic diversity of 210 soybean mutant lines (8 cultivars and 202 mutants) was performed through a TRAP analysis. Sixteen primer combinations amplified a total of 551 fragments. The highest (84.00%) and lowest (32.35%) polymorphism levels were obtained with primers MIR157B + Ga5 and B14G14B + Ga3, respectively. The mean PIC values 0.15 varied among the primer combination ranging from 0.07 in B14G14B + Sal2 to 0.23 in MIR157B + Sa4. Phylogenetic, principal component analysis (PCA) and structure analysis indicated that the 210 lines belong to four groups based on the 16 combination TRAP markers. AMOVA showed 21.0% and 79.0% variations among and within the population, respectively. Overall, the genetic similarity of each cultivar and its mutants were higher than within other mutant populations. Our results suggest that the TRAP marker system may be useful for assessing the genetic diversity among soybean mutants and help to improve our knowledge of soybean mutation breeding.