• Korean Journal of Plant Resources
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• v.17 no.3
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• pp.227-238
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• 2004

Rhododendron micranthum is an endangered species in Korea. In order to develop the strategy of gene diversity conservation, estimation of the amount of genetic diversity, the genetic variation and relationship in the native populations of Rh. micranthum was performed on the basis of AFLP and RAPD analysis. Analysis of 56 accessions derived from 6 populations of Rh. micranthum with four AFLP primer combinations and ten RAPD primers detected a total of 33 polymorphic AFLP fragments and 15 polymorphic RAPD fragments, respectively. By UPGMA cluster analysis with molecular markers, the 56 accessions were grouped into three major clusters at 73.3% genetic similarity; group I consists of most accessions of populations I, II, IV, V and Ⅵ, group II consists of 7 accessions of population III, and group III consists of only two accessions of population IV. The geographic locations of the most accessions derived from six populations were not related to their position in the UPGMA cluster analysis, except for several accessions of populations III and IV. The genetic similarity of among six populations measured by AFLP and RAPD markers ranged from 0.66 to 0.99. Among them, population Ⅵ showed the highest GS with means of 0.87, while population I showed the lowest GS with means of 0.78. This result will be useful for designing the strategy of conservation in the native populations of Rh. micranthum.

• Korean Journal of Plant Taxonomy
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• v.46 no.4
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• pp.371-377
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• 2016

The succulent herbaceous perennial Sedum sarmentosum commonly grows in the southern part of the Korean Peninsula. It is a species native to China, most likely introduced into Korea due to its edible and medicinal uses. If plants were introduced from a single source, we would expect no or low levels of genetic variation in Korean populations. Alternatively, if plants were introduced from multiple sources, we would expect, in contrast, high levels of genetic diversity. To test which is more likely, we surveyed the degree of allozyme variation in ten populations of this species from southern Korea. We found that S. sarmentosum was monomorphic at all fifteen allozyme loci. However, two congeners (S. polytrichoides and S. kamtschaticum) and two related species (Hylotelephium ussuriense and H. verticillatum) maintain moderate to high levels of genetic diversity ($H_e=0.144$, 0.203, 0.201, and 0.204, respectively). We suggest that southern Korean populations of S. sarmentosum likely descended from a single introduction of a few plants and then became naturalized exclusively via vegetative spreading (as plants in Korea, but also as occurs in other parts of its native and naturalized range, are sterile).

• Korean journal of applied entomology
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• v.50 no.4
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• pp.325-333
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• 2011

This study focused on the green peach aphid, Myzus persicae, as an indicator pest in Chinese cabbage cultivation to develop a genetic marker. We hypothesized that M. persicae gene flow is related to climate change. Genetic variation was analyzed using five local populations collected at different altitudes (157 m, 296 m, 560 m, 756 m and 932 m above sea level) in Hoengseong, Pyeongchang, and Gangneung areas, plus a laboratory strain used as an outgroup. There were no differences in ecological characteristics among strains. Esterase isozyme pattern and inter-simple sequence repeat (ISSR) PCR results showed significantly different bands between laboratory and wild, local populations. However, there was no difference among local populations. Partial fragments of ribosomal RNA (rRNA) and mitochondrial cytochrome oxidase I (mtCO I) were amplified and their nucleotide sequence was analyzed. Single nucleotide polymorphisms (SNPs) were detected in internal transcribed spacer-2 (ITS-2) and mtCO I regions among the five local populations. These SNPs can be use to discriminate different populations of M. persicae to monitor gene flow.

• Korean Journal of Breeding Science
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• v.50 no.4
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• pp.434-441
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• 2018

High-density genetic linkage mapping is critical for undertaking marker-assisted selection and confirming quantitative trait loci, as well as helping to build pseudomolecules of genomes. We constructed a genetic map using 94 $F_1$ populations generated from the interspecific cross between Korean cultivar "Wonwhang" (Pyrus pyrifolia, NCBI BioSample SAMN05196235) and European cultivar "Bartlett" (Pyrus communis). We designed a total of 24,267 SSR markers based on the genome sequences of "Wonwhang" for this. To select the markers that are linked to the traits important in pear breeding programs, SSR-containing genomic sequences were subjected to nucleotide sequence homology searches, which resulted in 510 SSR markers with high similarity to genes encoding proteins with putative functions such as transcription factors, resistance proteins, flowering time, and regulatory genes. Of these, 70 markers showed polymorphisms in parents and segregating populations and were used to construct a genetic linkage map, together with the unpublished 579 SNPs obtained from genotyping by sequencing analysis. The genetic linkage map covered 3,784.2 cM and the average distance between adjacent markers was 5.8 cM. Seventy SSR markers were distributed across 17 chromosomes with more than one locus.

• Korean journal of applied entomology
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• v.37 no.1
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• pp.19-22
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• 1998

Number of loci, allele frequencies, and subunit structures of 17 kinds of isozymes were analyzed in a laboratory strain of the beet armyworm, Spodoptera exigua (Hubner) to get genetic markers. These isozymes had 30 loci with 21 polymorphic (70.0% polymorphism); effective number of alleles per locus, average heterozygosity (H,), and inbreeding coefficient (F) were 2.52, 32.8%, and 2 1.0%, respectively.

• Journal of Embryo Transfer
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• v.11 no.1
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• pp.1-6
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• 1996

다배란 수정란이식(MOET)과 체외수정(IVF)기술을 이용한 육종체계에서 예상되는 유전적 개량량을 여러 집단의 크기에서 비교한 결과 체외수정기술이 MOET육종기술보다 특히 개량대상 유전력이 낮을때 훨씬 효율적으로 나타났다. 그러나 유전력이 높아지면 (h$^2$=0.3, 0.5), MOET와 IVF간의 상대적 차이는 미진하게 나타났다. 체외수정을 이용한 육종기술에서 암컷의 선발 강도는 대단히 높일 수 있는 반면 난자의 회수율이 많을수록 상대적으로 수컷에 대한 선발 강도는 낮아진다. 그 이유는 한 가계에서 근친을 피하기 위해 한 마리의 수컷만 선발해야 하므로 수소의 선발강도는 난자의 회수율이 높을수록 상대적으로 낮아진다. 여러 수준의 난자회수율(10, 20, 30, 50, 100)중에서 30일 때 가장 높은 유전적 개량을 나타내었다. (Key word: MOET, IVF,selection responses)

• The Korean Journal of Zoology
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• v.38 no.3
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• pp.324-329
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• 1995

The phylogenetic relationships between Cheju native horses and Tsushima native horses were studied by protein polymorphism analyses in 16 gene loci (Trypsin inhibitor: Ti, Chymotrypsin inhibitor: CTi, Albumin: Al, Esterase: Es, Transferrin: Tf, Hemoglobin: Hb, Catalase: Cat, Esterase D: EsD, Glutamate oxaloacetate transaminase: GOT, Glyoxalase I: GLO I, Acid phosphatase: AcP, Superoxide dismutase: SOD, Lactate dehydrogenase: LDH, Hexokinase: HK, Malate dehydrogenase: MDH, Malic enzyme: ME). All allelic patterns of the protein loci, except 5 loci (SOD, LDH, HK, MDH, ME), were polymorphic in both two populations. Gene frequencies of the polymorphic loci of the population of Cheju native horses were higher than those of Tsushima native horses. Average heterozygosity in Cheju native horses was 0.375, showing higher than that of Tsushima native horses (0.304). The Da distance and gene identity of two populations were 0.108 and 0.868, respectively. The phylogenetic tree constructed by these results and those previously reported in other horse populations, consisted of three clusters. From this phylogenetic tree, it could be suggested that Cheju native horses and Tsushima native horses had diverged from the Mongolian wild horse (Equus prsewolskii).

• Korean Journal of Ichthyology
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• v.27 no.1
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• pp.10-15
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• 2015

Giant grouper (Epinephelus lanceolatus) is a endangered species considered as a vulnerable grade-organism in the International Union for Conservation of Nature (IUCN) red list. As a fundamental baseline study for establishing a giant grouper broodstock management system, the efficiency for parentage analysis was evaluated by using microsatellite makers previously available in this species. The eight microsatellites generated a total 52 alleles from 32 individuals, the mean expected heterozygosity was 0.663, and mean inbreeding coefficient was 0.011, consequently suggesting that the present broodstock has retained the high level of genetic diversity. However, our analysis also recommended the collection of more broodfish for more stable brood line, since the estimated value of the effective population size was proven to be 35. The average probability of identity was $6.85{\times}10^{-11}$. NE-2P and NE-PP of paternity non-exclusion probabilities were 0.00835 and 0.00027, respectively. As the result of principle coordinate analysis, the genotype of broodstock was not overlapped, suggesting that the management system of giant grouper based on eight selected microsatellite markers might be effective, although further validation with extended number of broodfish might also be needed in future. Data of present study could be a useful basis to avoid the unwanted selection of broodfish that possess close genetic relationship with current broodstock, and consequently to establish effective broodstock management system allowing the production of progeny with high genetic diversity.

• Korean Journal of Ichthyology
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• v.17 no.3
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• pp.173-186
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• 2005

Genomic DNA was isolated from two geographic populations of largehead hairtail (Trichiurus lepturus) in Korea and the Atlantic Ocean. The eight arbitrarily selected primers were found to generate common, polymorphic, and specific fragments. The complexity of the banding patterns varied dramatically between primers from the two locations. The size of the DNA fragments also varied widely, from 150 bp (base pairs) to 3,000 bp. Here, 947 fragments were identified in the largehead hairtail population from Korea, and 642 in the largehead hairtail population from the Atlantic Ocean: 148 specific fragments (15.6%) in the Korean population, and 61 (9.5%) in the Atlantic population. In the Korean population, 638 common fragments with an average of 79.8 per primer were observed.; 429 common fragments, with an average of 53.6 per primer, were identified in the Atlantic population. The number of polymorphic fragments in the largehead hairtail population from Korea and the Atlantic Ocean was 76 and 27, respectively. Based on the average bandsharing values of all samples, the similarity matrix ranged from 0.784 to 0.922 in the Korean population, and from 0.833 to 0.990 in the Atlantic population. The bandsharing value of individuals within the Atlantic population was much higher than in the Korean population. The dendrogram obtained by the eight primers indicated two genetic clusters: cluster 1 (KOREAN 01~KOREAN 11), and cluster 2 (ATLANTIC 12~ATLANTIC 22). Individual KOREAN no. 10 from Korea was genetically most closely related to KOREAN no. 11 in the Korean population (genetic distance = 0.038). Ultimately, individual KOREAN no. 01 of the Korean population was most distantly related to ATLANTIC no. 16 of the Atlantic population (genetic distance = 0.708).

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.12 no.2
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• pp.94-101
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• 2007

Analysis of population structure of Oncorhynchus keta, the most abundant salmon in the East Sea of Korea, has not been much carried out despite its importance as a fishery resource in the North Pacific. Currently, molecular methods are being applied to stock identification and a method of using single nucleotide polymorphisms (SNPs) is getting more popular. In this study, we analyzed the 720 bp long sequence of the mtDNA COIII-ND3-ND4L region in order to examine genetic similarity-dissimilarity among the Korea chum salmons of each stream and their relationship with the Japan chum salmons. A total of 152 individuals were analyzed, 108 from 3 locations of Korea and 44 from 2 locations of japan, which resulted in as many as 29 different haplotypes. Pairwise $F_{ST}$ and AMOVA tests of the populations show that there is no significant population-level genetic difference among the chum salmons analyzed ($F_{ST}<0.07$). On the other hand, haplotype relationships among the individuals reveal that approximately 25% of the Korea salmons consist genetic lineages independent of Japan salmons and also that a genetic lineage exists in the Puk river and the Namdae river salmons independent of the Wangpi river salmons of Korea.