• 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.10 no.4
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• pp.422-427
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• 1997

Breeding efficiency was investigated to reveal crucial factors for constructing effective breeding system with subdivided populations under equal genetic level. Simulation study of selection experiment was performed for 20 generations with 20 replications each, comparing average breeding values and inbreeding coefficients between the two breeding systems; single population scheme and two population scheme, each of which had the same genetic parameters. Genetic correlations (-0.5 to 0.5) were assumed to be caused only by pleiotropic effect of a gene. Phenotypes of the two traits generated by polygenic effect with additive 36 loci and residuals distributed normally were selected by two traits selection index procedure. Comparing between the single population scheme and the two population scheme, the single population scheme showed higher genetic gain with lower inbreeding coefficient. This result was confirmed particularly for the situation of high selection intensity, high heritability and high degree of unevenness for economic weight. Genetic correlations in the single population scheme were significantly lower than the two population scheme when initial genetic correlation was negative. When terminal crossbreeding for the two population scheme is taken into account, superiority of the two population scheme was suggested. The terminal crossbreeding was effective under the situation of long term selection, existence of moderate inbreeding depression and use of less extreme economic weight.

• Proceedings of the National Institute of Ecology of the Republic of Korea
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• v.2 no.2
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• pp.120-128
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• 2021

The objective of this study was to analyze the genotype of black-spotted pond frog (Pelophylax nigromaculatus) using seven microsatellite loci to quantify its genetic diversity and population structure throughout the spatial scale of basins of Han, Geum, Yeongsan, and Nakdong Rivers in South Korea. Genetic diversities in these four areas were compared using diversity index and inbreeding coefficient obtained from the number and frequency of alleles as well as heterozygosity. Additionally, the population structure was confirmed with population differentiation, Nei's genetic distance, multivariate analysis, and Bayesian clustering analysis. Interestingly, a negative genetic diversity pattern was observed in the Han River basin, indicating possible recent habitat disturbances or population declines. In contrast, a positive genetic diversity pattern was found for the population in the Nakdong River basin that had remained the most stable. Results of population structure suggested that populations of black-spotted pond frogs distributed in these four river basins were genetically independent. In particular, the population of the Nakdong River basin had the greatest genetic distance, indicating that it might have originated from an independent population. These results support the use of genetics in addition to designations strictly based on geographic stream areas to define the spatial scale of populations for management and conservation practices.

• Development and Reproduction
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• v.23 no.2
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• pp.193-198
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• 2019

Genomic DNA samples were obtained from cultured penaeid shrimp (Penaeus chinensis) individuals such as fresh shrimp population (FSP) and deceased shrimp population (DSP) from Shinan regions in the Korean peninsula. In this study, 233 loci were identified in the FSP shrimp population and 162 in the DSP shrimp population: 33 specific loci (14.2%) in the FSP shrimp population and 42 (25.9%) in the DSP population. A total of 66 (an average of 9.4 per primer) were observed in DSP shrimp population, whereas 55 unique loci to each population (an average of 7.9 per primer) in the FSP shrimp population. The Hierarchical dendrogram extended by the seven oligonucleotides primers indicates three genetic clusters: cluster 1 (FRESH 01, 02, and DECEASED 12, 13, 15, 16, 17, 19, 20, 22) and cluster 2 (FRESH 03, 04, 05, 06, 07, 08, 09, 10, 11, and DECEASED 14, 18, 21). Among the twenty-two shrimp, the shortest genetic distance that exposed significant molecular differences was between individuals 20 and 16 from the DSP shrimp population (genetic distance=0.071), while the longest genetic distance among the twenty-two individuals that established significant molecular differences was between individuals FRESH no. 02 and FRESH no. 04 (genetic distance=0.477). In due course, PCR analysis has revealed the significant genetic distance among two penaeid shrimp populations.

• Development and Reproduction
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• v.18 no.3
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• pp.167-172
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• 2014

In the present study, muscle tissues were obtained separately from individuals from Atlantic hairtail population (AHP), Gunsan hairtail population (GHP) and Chinese hairtail population (CHP), respectively. The seven decamer primers were used to generate the shared loci, specific, unique shared loci to each population and shared loci by the three hairtail populations. Here, averagely, a decamer primer generated 64.7 amplified products per primer in the AHP population, 55.7 in GHP population and 56.4 in CHP population. The number of unique shared loci to each population and number of shared loci by the three populations generated by genetic analysis using 7 decamer primers in AHP, GHP and CHP population. 119 unique shared loci to each population, with an average of 17 per primer, were observed in the AHP population, and 28 loci, with an average of 4 per primer, were observed in the CHP population. The hierarchical dendrogram point out three main branches: cluster 1 (ATLANTIC 01 ~ ATLANTIC 07), cluster 2 (GUNSAN 08 ~ GUNSAN 14) and cluster 3 (CHINESE 15 ~ CHINESE 21). The shortest genetic distance displaying significant molecular difference was between individuals' CHINESE no. 16 and CHINESE no. 18 (0.045). In the long run, individual no. 01 of the AHP population was most distantly related to CHINESE no. 19 (genetic distance = 0.430). Consequently, PCR analysis generated on the genetic data displayed that the geographic AHP population was widely separated from CHP population, while individuals of CHP population were fairly closely related to those of GHP population.

• Development and Reproduction
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• v.17 no.4
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• pp.363-367
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• 2013

PCR analysis generated on the genetic data showed that the geographic hairtail (Trichiurus lepturus) population from Korea in the Yellow Sea was more or less separated from geographic hairtail population from China in the South Sea. The average bandsharing value ($mean{\pm}SD$) within hairtail population from Korea showed $0.859{\pm}0.031$, whereas $0.752{\pm}0.039$ within population from China. Also, bandsharing values between two hairtail populations ranged from 0.470 to 0.611, with an average of $0.542{\pm}0.059$. As compared separately, the bandsharing values of individuals within hairtail population from Korea were comparatively higher than those of individuals within population from China. The hierarchical dendrogram resulted from reliable oligonucleotides primers, indicating two genetic clusters composed of cluster 1 (KOREANHAIR1~KOREANHAIR11) and cluster 2 (CHINESEHAI12~CHINESEHAI22). The genetic distances between two geographic populations ranged from 0.038 to 0.476. Individual No. 11 within hairtail population from Korea was genetically closely related with No. 10 (genetic distance=0.038). The longest genetic distance (0.476) displaying significant molecular difference was also between individual No. 01 within hairtail population from Korea and No. 22 from Chinese. In the present study, PCR analysis has revealed significant genetic distances between two hairtail population pairs (P<0.05).

• Development and Reproduction
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• v.22 no.2
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• pp.193-198
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• 2018

The author undertook PCR-founded genetic platform to investigate the hierarchical dendrogram of Euclidean genetic distances of one razor clam population, particularly for Solen corneus, which was further associated with those of the other clam population, by engaging with the precisely designed oligonucleotide primer sets. Seven oligonucleotides primers were used producing a total of 639 counted bands in population A and 595 in population B, respectively, ranging in size of DNA fragments from larger than approximately 50 bp to less than 1,100 bp. Their primers generated 39 specific fragments (6.10%) in population A and 47 (7.90%) in population B, respectively Comparatively, individuals of one razor clam population were fairly related to that of the other clam population, as shown in the hierarchical dendrogram of Euclidean genetic distances. The analysis of genetic variation between razor clam populations could offer important statistics for fisheries and mariculture. Generally the results showed specific and/or conserved genetic loci between razor clam populations. Specific markers established by the author will be valuable for the genetic analysis, species protection and increase of razor clam individuals in coastal region of the Korean Peninsula.

• Development and Reproduction
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• v.21 no.4
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• pp.435-440
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• 2017

The author performed PCR-based genetic platform to measure the hierarchical dendrogram of Euclidean genetic distances of Korean scallop populations (KSP), particularly for Chlamys farreri, which was further compared with those of the Chinese scallop populations (CSP), by employing the with specifically designed oligonucleotide primer sets. The scallop is economically and ecologically very important bivalves in South Korea. Relatively, individuals of KSP population were fairly distantly related to that of CSP population, as shown in the hierarchical dendrogram of Euclidean genetic distances. Comparatively, individuals of KSP population were fairly distantly related to that of CSP population. Thus analysis of genetic difference between scallop populations could provide important statistics for fishery and aquaculture. Overall the results showed specific and/or conserved genetic loci between scallop populations. Information on the genetic distance of the bivalve would be helpful to understand scallop expansion or conservation in the coastal regions of South Korea. Specific markers developed by the author will be useful for the analysis of scallop population genetics and distribution in coastal region.

• Proceedings of the KAIS Fall Conference
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• 2003.11a
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• pp.80-83
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• 2003

A Genetic algorithm is a searching algorithm that based on the law of the survival of the fittest. Multi-population Genetic Algorithms are a modified form of genetic algorithm. Therefore, experience with fuzzy logic and genetic algorithm has proven to be that a combination of them can efficiently make up for their own deficiency. The Multi-population Genetic Algorithms independently evolve subpopulations. In this paper, we suggest a new coding method that independently evolves subpopulations using the fuzzy logic controller. The fuzzy logic controller has applied two fuzzy logic controllers that are implemented to adaptively adjust the crossover rate and mutation rate during the optimization process. The migration scheme in the multi-population genetic algorithms using fuzzy logic controllers is tested for a function optimization problem, and compared with other group migration schemes, therefore the groups migration scheme is then performed. The results demonstrate that the migration scheme in the multi-population genetic algorithms using fuzzy logic controller has a much better performance.

• Animal cells and systems
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• v.16 no.1
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• pp.41-49
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• 2012

Eighteen new polymorphic microsatellite markers were developed for the Korean mi-iuy croaker ($Miichthys$ $miiuy$, Perciformes, Sciaenidae), and allelic variability was compared between a wild population in Mokpo, Korea, and a hatchery population in Tongyeong, Korea. All loci were amplified readily and demonstrated allelic variability, with the number of alleles ranging from 5 to 37 in the wild population, and from 4 to 12 in the farmed population. The average observed and expected heterozygosities were estimated, respectively, to be 0.74 and 0.78 in the hatchery population samples, and 0.79 and 0.86 in the wild samples. These results indicate lower genetic variability in the hatchery population compared with the wild population, and significant genetic differentiation between the wild population and the hatchery samples ($F_{ST}$=0.058, P<0.001). These microsatellite loci may be valuable for future population genetic studies, monitoring changes in the genetic variation within stocks in a commercial breeding program, conservation genetics, and molecular assisted selective breeding of the mi-iuy croaker in the future.