• 한국경영과학회:학술대회논문집
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• 한국경영과학회/대한산업공학회 2005년도 춘계공동학술대회 발표논문
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• pp.614-620
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• 2005

Ensemble에서 feature selection은 각 classifier의 학습할 데이터의 변수를 다르게 하여 diversity를 높이며, 이것은 일반적인 성능향상을 가져온다. Feature selection을 할 때 쓰는 방법 중의 하나가 Genetic Algorithm (GA)이며, GA-SVM은 GA를 기본으로 한 wrapper based feature selection mechanism으로 response model과 keystroke dynamics identity verification model을 만들 때 좋은 성능을 보였다. 하지만 population 안의 후보들간의 diversity를 보장해주지 못한다는 단점 때문에 classifier들의 accuracy와 diversity의 균형을 맞추기 위한 heuristic parameter setting이 존재하며 이를 조정해야만 하였다. 우리는 GA-SVM 알고리즘을 바탕으로, population안 후보들의 fitness를 측정할 때 accuracy와 diversity 둘 다 고려하는 fitness function을 도입하여 추가적인 classifier 선택 작업을 제거하면서 성능을 유지시키는 방안을 연구하였으며 결과적으로 알고리즘의 복잡성을 줄이면서도 모델의 성능을 유지시켰다.

• 한국자원식물학회지
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• 제28권4호
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• pp.411-418
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• 2015

Lonicera caerulea var. edulis is a rare species found in some alpine region of Korea. Genetic variation in L. caerulea var. edulis has been investigated by examining 161 individuals from six natural populations: Mt. Seorak 1, Mt. Seorak 2, Mt. Jeombong, Mt. Bangtae, Mt. Gyebang, Mt. Halla. The mean genetic diversity for all the six populations was 0.25 (S.I.). The highest genetic diversity was found in Mt. Seorak (S.I.=0.3158) and the lowest was in Mt. Gyebang (S.I.=0.1047). Comparatively low level of genetic diversity was observed (Ae=1.25, P= 64.6%, S.I.=0.25), which is a typical pattern for rare tree species. AMOVA showed exceptionally large proportion of genetic variations both for among populations (34.69%) and within populations (65.31%). Excluding Mt. Gyebang, the genetic variation among and within population was 18.71% and 81.29% respectively. The UPGMA dendrogram based on genetic distance is not suitable for geographic relationship. Genetic distance of Mt. Gyebang was most distant from the other populations. Excluding Mt. Gyebang, the genetic identities among the five populations were 0.95 to 0.97, which is very high similarity level of genetic identity. This low level of genetic variations and the lack of site in nature indicates that Lonicera caerulea var. edulis demanded a serious conservation.

• 한국작물학회:학술대회논문집
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• 한국작물학회 2017년도 9th Asian Crop Science Association conference
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• pp.85-85
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• 2017

Potato is important carbohydrate source over the world in that revealing high productivity per the unit area, and their cultivation area is estimated to be increased to cope with a scarcity of food according to the population increase. Major cultivated species of potato is Solanum tuberosum (2n = 4x = 48) and regarded as being originated in Andes region of South America. The diverse potato genetic resources has been collected and perserved in Highland Agricultural Research Institute (NICS, RDA), and the genetic materials as DNA stock is conserved in National Agrobiodiversity Center(NAS, RDA). The understanding of genetic constitution of conserved diversity is the basis for the germplam management and further utilization. In this study, we analyzed the genetic diversity of potato germplasm(479 accessions) using 24 microsatellite markers which have been internationally used for fingerprinting of potato accession. The allele number and polymorphic information content (PIC) of total accessions per locus was ranged from 2 to 18 (mean = 8.2) and from 0.214 to 0.771 (mean = 0.595), respectively. Especially, the accession originated from Korea revealed average allele number of 6.0 (2 - 11) and average PIC value of 0.58 (0.193 - 0.763). Three groups were deduced by phylogenic analysis (Group-1, -2, -3); Korean accessions showed close genetic similarity to Japanese and USA accessions, and Korean landraces were mainly included in Group-3. We try to elaborate the genetic diversity analysis of conserved potato germplasm by acquiring more genotypes using applicable molecular markers.

• Asian-Australasian Journal of Animal Sciences
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• 제31권12호
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• pp.1871-1880
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• 2018

Objective: Recently, there has been an increasing interest in conservation of native genetic resources of chicken on a worldwide basis. Most of the native chicken breeds are threatened by extinction or crossing with ecotypes. Methods: Six Saudi native chicken breeds including black naked neck, brown frizzled, black, black barred, brown and gray were used in the current study. The aim of the current study was to evaluate genetic diversity, relationship and population structure of Saudi native chicken breeds based on 20 microsatellite markers. Results: A total of 172 alleles were detected in Saudi native chicken breeds across all 20 microsatellite loci. The mean number of alleles per breed ranged from 4.35 in gray breed to 5.45 in normally feathered black with an average of 8.6 alleles. All breeds were characterized by a high degree of genetic diversity, with the lowest heterozygosity found in the brown breed (72%) and the greatest in the frizzled and black barred populations (78%). Higher estimate of expected heterozygosity (0.68) was found in both black breeds (normal and naked neck) compared to the other chicken populations. All studied breeds showed no inbreeding within breed (negative inbreeding coefficient [$F_{IS}$]). The phylogenetic relationships of chickens were examined using neighbor-joining trees constructed at the level of breeds and individual samples. The neighbor-joining tree constructed at breed level revealed three main clusters, with naked neck and gray breeds in one cluster, and brown and frizzled in the second cluster leaving black barred in a separate one. Conclusion: It could be concluded that the genetic information derived from the current study can be used as a guide for genetic improvement and conservation in further breeding programs. Our findings indicate that the Saudi native chicken populations have a rich genetic diversity and show a high polymorphism.

• Journal of Animal Science and Technology
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• 제63권2호
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• pp.248-261
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• 2021

Attributable to their major function in pathogen recognition, the use of bovine leukocyte antigens (BoLA) as disease markers in immunological traits in cattle is well established. However, limited report exists on polymorphism of the BoLA gene in zebu cattle breeds by high resolution typing methods. Thus, we used a polymerase chain reaction sequence-based typing (PCR-SBT) method to sequence exon 2 of the BoLA class II DRB3 gene from 100 animals (Boran, n = 13; Sheko, n = 20; Fogera, n = 16; Horro, n = 19), Hanwoo cattle (n = 18) and Bangladesh Red Chittagong zebu (n = 14). Out of the 59 detected alleles, 43 were already deposited under the Immuno Polymorphism Database for major histocompatibility complex (IPD-MHC) while 16 were unique to this study. Assessment of the level of genetic variability at the population and sequence levels with genetic distance in the breeds considered in this study showed that Zebu breeds had a gene diversity score greater than 0.752, nucleotide diversity score greater than 0.152, and mean number of pairwise differences higher than 14, being very comparable to those investigated for other cattle breeds. Regarding neutrality tests analyzed, we investigated that all the breeds except Hanwoo had an excess number of alleles and could be expected from a recent population expansion or genetic hitchhiking. Howbeit, the observed heterozygosity was not significantly (p < 0.05) higher than the expected heterozygosity. The Hardy Weinberg equilibrium (HWE) analysis revealed non-significant excess of heterozygote animals, indicative of plausible over-dominant selection. The pairwise FST values suggested a low genetic variation among all the breeds (FST = 0.056; p < 0.05), besides the rooting from the evolutionary or domestication history of the cattle. No detached clade was observed in the evolutionary divergence study of the BoLA-DRB3 gene, inferred from the phylogenetic tree based on the maximum likelihood model. The investigation herein indicated the clear differences in BoLA-DRB3 gene variability between African and Asian cattle breeds.

• 한국산림과학회지
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• 제103권1호
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• pp.59-64
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• 2014

본 연구에서는 물황철나무(Populus koreana Rehder) 집단을 대상으로 I-SSR 표지자를 이용해 유전다양성과 유전적 공간구조를 분석하였다. 물황철나무는 중국, 러시아 극동지역과 북한의 고산 계곡부 등에 서식하는 낙엽활엽 교목이다. 물황철나무는 남한에서 강원도 일대에 제한적으로 분포한다. 특히 오대산 집단은 물황철나무의 남방한계지로서 유전자원보존의 중요성이 강조된다. 8개의 I-SSR primer로 유전다양성을 추정한 결과, Shannon의 다양성 지수(I)는 0.230, 이형접합도의 기대치(He)는 0.151로 유사한 생활사를 갖는 타 수종에 비해 유전다양성이 매우 낮게 나타났다. 유전적 군락을 확인하기 위해 공간적 자기상관성 분석을 수행한 결과, 조사 지역 내의 물황철나무 집단은 400 m 이내에서 유전적으로 유사한 군락구조를 갖고 있는 것으로 나타났다. 물황철나무 집단의 현지외 유전자 보존을 위한 표본추출 시, 개체 간 거리를 400 m 이상으로 두는 것이 효율적일 것으로 판단된다.

• 한국식물학회:학술대회논문집
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• 한국식물학회 2001년도 춘계학술발표대회:발표눈문요지록
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• pp.18-18
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• 2001

• Asian-Australasian Journal of Animal Sciences
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• 제19권12호
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• pp.1685-1690
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• 2006

Kenkatha cattle, a draft purpose breed, which can survive in a harsh environment on low quality forage, was explored genetically exploiting FAO-suggested microsatellite markers. The microsatellite genotypes were derived by means of the polymerase chain reaction (PCR) followed by electrophoretic separation in agarose gels. The PCR amplicons were visualized by silver staining. The allelic as well as genotypic frequencies, heterozygosities and gene diversity were estimated using standard techniques. A total of 125 alleles was distinguished by the 21 microsatellite markers investigated. All the microsatellites were highly polymorphic with mean allelic number of 5.95${\pm}$1.9 (ranging from 3-10 per locus). The observed heterozygosity in the population ranged between 0.250 and 0.826 with a mean of 0.540${\pm}$0.171, signifying considerable genetic variation. Bottleneck was examined assuming all three mutation models which showed that the population has not experienced bottleneck in recent past. The population displayed a heterozygote deficit of 21.4%. The study suggests that the breed needs to be conserved by providing purebred animals in the breeding tract.

• 한국어류학회지
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• 제22권2호
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• pp.115-120
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• 2010

납자루 Acheilognathus lanceolatus의 유전 변이와 집단 구조를 알아보기 한국의 5개 집단(한강과 금강, 동진강, 섬진강, 낙동강)과 일본의 1개 집단(Katsura River)을 대상으로 AFLP 분석을 수행하였다. 5개의 선택적 프라이머 조합에 의 해 검출된 집단별 유효 밴드의 수는 345~374개였으며, 다형성 밴드 수는 55 (15.0%)~131 (24.9%)개였다. 평균 유전적 다양성은 낙동강 집단이 가장 높은 값을 보였고 한강 집단이 가장 낮은 값을 보였다. 계통도 상에서 각 수계별로 채집된 개체는 각 집단별로 함께 분기하으며, 이들은 높은 bootstrap 값으로 지지되는 2개의 단계통군 또는 집단 그룹으로 나누어졌다. 한편 유전적 분화도($F_{ST}$)는 모든 집단 간에 유의적 차이를 보였다(P<0.01). 집단 그룹 간의 유전적 변이 수준을 알아보기 위해 AMOVA 분석을 실시한 결과 총 25.49%의 변이(P<0.01)을 보여 이들 집단 그룹은 유전적으로 명확히 구분되었다.

• Animal Systematics, Evolution and Diversity
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• 제24권1호
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• pp.25-32
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• 2008

The Gold-spotted pond frog, Rana plancyi chosenica, designated as a vulnerable species by IUCN Red list. This species is a typical example facing local population threats and extinction due to human activities in South Korea. A strategic conservation plan for this endangered species is urgently needed. In order to provide information for future conservation planning, accurate information on the genetic diversity and taxonomic status is needed for the establishment of conservation units for this species. In this study, we used a molecular genetic approach using the mitochondrial cytochrome b gene and control region sequences to find the genetic diversity of gold-spotted pond frogs within South Korea. We sequenced the mitochondrial DNA cytochrome b gene and control region of 77 individuals from 11 populations in South Korea, and one from Chongqing, China. A total of 15 cytochrome b gene haplotypes and 34 control region haplotypes were identified from Korean gold-spotted pond frogs. Mean sequence diversity among Korean gold-spotted pond frogs was 0.31% (0.0-0.8%) and 0.51% (0.0-1.0%), respectively. Most Korean populations had at least one unique haplotype for each locus. The Taean, Ansan and Cheongwon populations had no haplotypes shared with other populations. There was a sequence divergence between Korean and Chinese gold-spotted pond frogs (1.3% for cyt b; 2.9% for control region). Analysis of genetic distances and phylogenetic trees based on both cytochrome b and control region sequences indicate that the Korean gold-spotted pond frog are genetically differentiated from those in China.