• Asian-Australasian Journal of Animal Sciences
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• v.25 no.3
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• pp.299-303
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• 2012

Inbreeding is the mating of relatives that produce progeny having more homozygous alleles than non-inbred animals. Inbreeding increases numbers of recessive alleles, which is often associated with decreased performance known as inbreeding depression. The magnitude of inbreeding depression depends on the level of inbreeding in the animal. Level of inbreeding is expressed by the inbreeding coefficient. One breeding goal in livestock is uniform productivity while maintaining acceptable inbreeding levels, especially keeping inbreeding less than 20%. However, in closed herds without the introduction of new genetic sources high levels of inbreeding over time are unavoidable. One method that increases selection response and minimizes inbreeding is selection of individuals by weighting estimated breeding values with average relationships among individuals. Optimum genetic contribution theory (OGC) uses relationships among individuals as weighting factors. The algorithm is as follows: i) Identify the individual having the best EBV; ii) Calculate average relationships ($\bar{r_j}$) between selected and candidates; iii) Select the individual having the best EBV adjusted for average relationships using the weighting factor k, $EBV^*=EBV_j(1-k\bar{{r}_j})$ Repeat process until the number of individuals selected equals number required. The objective of this study was to compare simulated results based on OGC selection under different conditions over 30 generations. Individuals (n = 110) were generated for the base population with pseudo random numbers of N~ (0, 3), ten were assumed male, and the remainder female. Each male was mated to ten females, and every female was assumed to have 5 progeny resulting in 500 individuals in the following generation. Results showed the OGC algorithm effectively controlled inbreeding and maintained consistent increases in selection response. Difference in breeding values between selection with OGC algorithm and by EBV only was 8%, however, rate of inbreeding was controlled by 47% after 20 generation. These results indicate that the OGC algorithm can be used effectively in long-term selection programs.

• Journal of Aquaculture
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• v.21 no.4
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• pp.346-350
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• 2008

RAPD analysis was examined to estimate the availability as a genetic marker. The availability was evaluated in terms of genetic divergence and relationships among Haliotis discus hannai, H. rufescens, H. rubra and H. midae in both hemispheres of the world. In results, RAPD analysis showed a clear genetic divergence between every pair of species. However, genetic relationships among the four species estimated by RAPD analysis unreflected to geographical distribution and morphological characteristics. In conclusion, RAPD is suitable genetic markers for estimates of genetic divergence and differences among abalone species.

• Journal of Sericultural and Entomological Science
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• v.39 no.2
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• pp.119-133
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• 1997

Isozyme was used to characterize general protein patterns of genetic relationships among 303 silkworm stocks preserved in National Sericultural and Entomology Research Institute, RDA. Six isozymes (esterase, acid phosphatase, alkaline phosphatase, amylase, glucose-6-phosphate dehydrogenase and sucrase) from hemolymph, midgut, and digestive juice were employed to construct dendograms(UPGMA method) using a polycrylamide gel electrophoresis. A cluster analysis revealed four major group, which were divided into several subgroups within each group, contained assemglages of Japanese and Chinese races. Especially, genetic differentiation in the first and second group was greatest rather than within Japanese and Chinese races repectively and was concordant with the hypothesis of phyletic sorting of initial variability in China many years ago. Hypothesized recent introgression between groups was also plausible, but the eviednce suggested bidirectional gene flow between the Chinese and the Japnaese lineages. Interpreting the results in light of evidence from the current study, the genetic diversity and relationship showed in Korean silkworm race, Hansammyun reflected early and independent evolution from the Chinese ancestor, limited addition of new variability and phyletic sorting within Korean peninsula more than 4,000 years.

• Asian-Australasian Journal of Animal Sciences
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• v.19 no.9
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• pp.1245-1251
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• 2006

This study was carried out to determine the genetic relationships among seven west African goat breeds : Casamance Goat (Kolda, Senegal), Labe Goat (Fouta Djallon, Guinea), three Sahel Goat (Djoloff, Senegal ; Maradi, Niger; Gorgol, Mauritania) red Sokoto Goat (Maradi, Niger) and Guera goat (Atar, Mauritania).The polymorphism of six microsatellites and the ${\alpha}_{s1}$-casein locus was analysed. The six microsatellite loci were polymorphic with a mean number of alleles ranging from 2.71 to 4.0. At the ${\alpha}_{s1}$-casein locus, A and B were the most frequent alleles, which are known to be associated with a high level of protein synthesis. A neighbour-joining tree and a Principal Component Analysis were performed and the reliability of both methods was tested. Our study shows that the genetic relationships among the breeds analysed correspond to their geographical distribution and in addition, that the Labe Goat is strongly separated from the other breeds. Among the seven markers used, four have an effect on the distribution of breeds while three seem to be non-informative.

• Animal cells and systems
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• v.4 no.2
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• pp.117-121
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• 2000

Genetic relationships among six species of the genus Rana from Korea were investigated by complete nucleotide sequence analyses of mitochondrial cytochrome b gene (1143 bp). Based on Kimura-2-parameter distance, the interspecific sequence differences of cytochrome b gene within the genus Rana were ranged from 7.83% to 25.00%. The genetic distances were 7.83% between R. nigromaculata and R. plancyi, 8.47% between two types of R. rugosa (type A and B), 10.42% between the brown frogs (R. amurensis and R. dybowskii), 16.11% between R. dybowskii types 1 and 2 and 12.36% between pond frogs (R. nigromaculata and R. plancyi) and R. catesbeiana. In the neighbor-joining and parsimony trees, R. catesbeiana was more closely related to pond frogs than brown frogs. R. dybowskii types 1 and 2 were considered to be at a distinct and specific level of differentiation (16.11%), while two types of R. rugosa were suspected to be at a subspecific level (8.47%).

• Plant Resources
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• v.8 no.2
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• pp.135-144
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• 2005

RAPD analysis was performed to discuss the taxonomic status and phylogenetic relationships among the tribe Forsythieae and related groups. Two hundred and eighteen scorable polymorphic bands were detected from fourteen oligonucleotide primers. From the results of RAPD analysis by Nei and Li's genetic distance, each individuals of Abeliophyllum distichum showed high genetic relationships with ranging from 0.085 to 0.301, also the genus Forsythia showed from 0.042 to 0.655 among the species and populations. But, Abeliophyllum and Forsythia showed distinct dissimilarity, ranging from 0.610 to 1.258. And genetic differences among the population of Forsythia were 0.042 in F. koreana, 0.275 in F. saxatilis, 0.275 in F. ovata, 0.279 in F. nakaii, and 0.249 in F. viridissima. The UPGMA phenogram of tribe Forsythieae based on the results of RAPD analysis were presented that Abeliophyllum is distinct genus different from Forsythia. NJ tree which applied as the outgroups Fontanesia and Jasminum was derived, and it showed that tribe Forsythieae might be a monophyletic group. The genus Fontanesia was showed as sister group of tribe Forsythieae. Among the populations of taxa in Forsythia, F. koreana and F. saxatilis were more closely related, and F. ovata and F. nakaii were very closely related to F.japonica. And Fontanesia was the sister group of tribe Forsythieae.

• Journal of Korean Society of Forest Science
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• v.87 no.2
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• pp.153-163
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• 1998

Genetic relationships of some poplars in the section Leuce, including 5 species and 11 clones of Populus alba${\times}$glandulosa, were investigated on the basis of RAPD marker analysis. Twenty-two of the 88 arbitrary 10-mer primers, showed reproducible amplification in the preliminary experiment with 6 samples, were used for PCR and generated a total of 181 RAPD markers. Genetic relationships among the analyzed samples were tested by two phenetic methods of the UPGMA and the neighbor-joining, which revealed the close genetic relationship between P. glandulosa and P. alba. And the close genetic relationship between P. glandulosa and P. davidiana was ascertained by the principal component analysis. Based on the observation of the close genetic relationship between them, it was deduced that P. glandulosa might be originated by the saltational speciation caused by the hybridization between P. alba and P. davidiana in nature.

• Asian-Australasian Journal of Animal Sciences
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• v.30 no.10
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• pp.1365-1371
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• 2017

Objective: This study was conducted to investigate the basic information on genetic structure and characteristics of Korean Native chickens (NC) and foreign breeds through the analysis of the pure chicken populations and commercial chicken lines of the Hanhyup Company which are popular in the NC market, using the 20 microsatellite markers. Methods: In this study, the genetic diversity and phylogenetic relationships of 445 NC from five different breeds (NC, Leghorn [LH], Cornish [CS], Rhode Island Red [RIR], and Hanhyup [HH] commercial line) were investigated by performing genotyping using 20 microsatellite markers. Results: The highest genetic distance was observed between RIR and LH (18.9%), whereas the lowest genetic distance was observed between HH and NC (2.7%). In the principal coordinates analysis (PCoA) illustrated by the first component, LH was clearly separated from the other groups. The correspondence analysis showed close relationship among individuals belonging to the NC, CS, and HH lines. From the STRUCTURE program, the presence of 5 clusters was detected and it was found that the proportion of membership in the different clusters was almost comparable among the breeds with the exception of one breed (HH), although it was highest in LH (0.987) and lowest in CS (0.578). For the cluster 1 it was high in HH (0.582) and in CS (0.368), while for the cluster 4 it was relatively higher in HH (0.392) than other breeds. Conclusion: Our study showed useful genetic diversity and phylogenetic relationship data that can be utilized for NC breeding and development by the commercial chicken industry to meet consumer demands.

• Asian-Australasian Journal of Animal Sciences
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• v.17 no.4
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• pp.445-452
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• 2004

Genetic diversity of sub-Saharan African goats was assessed using 19 microsatellite markers. Breeds were sampled from eastern Africa (Maasai, Kigezi, Mubende, North West Highland, Arsi-Bale), southern Africa (Ndebele, Pafuri) and West Africa (West African Dwarf, Maure, Djallonke). European breeds (Grisons Striped, Toggenburg), Asian breeds (Mongolian Cashmere, Bandipur) and a Middle East breed (Arab) were also included. The mean number of alleles per locus and average gene diversity ranged from 5.26$\pm$0.464 (Djallonke) to 7.05$\pm$0.516 (Mubende) and from 0.542$\pm$0.036 (Pafuri) to 0.672$\pm$0.031 (Ndebele), respectively. The between breeds variation evaluated using $$G_{ST}$$ and $\theta$ were found to account for 14.6% ($\theta$) and 15.7% ($$G_{ST}$$) of the total genetic variation. The $D_{A}$ measure of genetic distance between pairs of breeds indicated that the largest genetic distance was between Pafuri and Djallonke while the lowest genetic distance was between Arsi-Bale and North West Highland. A neighbour-joining tree of breed relationships revealed that the breeds were grouped according to their geographic origins. Principal component analysis supported the grouping of the breeds according to their geographic origins. It was concluded that the relationships of sub-Saharan African goat breeds were according to their geographical locations implying that the goats of eastern Africa, West Africa and southern Africa are genetically distinct. Within each sub-region, goat populations could be differentiated according to morphological characteristics.

• Korean Journal of Plant Resources
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• v.22 no.2
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• pp.152-158
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• 2009

We performed RAPD analysis to investigate the inter-/intraspecific relationships and regional variations of Phragmites japonica and P. communis according to the environmental change. One hundred and fourty nine genetic effective polymorphic bands between 300 bp and 1,900 bp were marked from RAPD PCR with nine oligoprimers. From the RAPD analysis by Nei-Li's genetic distance, the dissimilarity indices among the populations of Phragmites japonica were relatively low from 0.012 to 0.061, and Phragmites communis were also low from 0.033 to 0.095. It showed the close genetic relationships among the same species populations, and both species were distinctly independent with relatively high level of dissimilarity indices (0.043 - 0.132). The obvious genetic markers to distinguish two species were confirmed and those profiles were suggested. From the UPGMA phenogram by RAPD analysis, both species showed the water environment related cluster patterns by distributional regions. RAPD analysis was useful to delimit two species taxonomically and to investigate the genetic relationships among inter-/intraspecific populations.