• Korean Journal of Agricultural Science
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• v.44 no.4
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• pp.549-557
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• 2017

As exchanges between countries become more active, new threats such as drugs, illegal imports of food and medicines, and terrorism are present all over the world. From this, increased border security that protects people's safety is becoming a new issue. The activities of special purpose dogs that detect these threats in advance are becoming very important. One of the obstacles in securing superior individuals is musculoskeletal disorders which interfere with the work of special purpose dogs. In order to search for genes associated with these genetic disorders, we conducted genomic analysis using linkage disequilibrium information and investigated genetic characteristics to know heterozygosity and inbreeding status in the population. In this study, two breeds (Malinois, Shepherd) of army dogs and three breeds (Malinois, Shepherd, Retriever) from public databases were used for comparison. The 170K SNP marker panel was used for this study. In the principal component analysis, it was confirmed that clusters were formed for each breed. The number of effective populations differed for each cultivar, but this was due to the difference in numbers of individuals for each breed used for the analysis. The results of heterozygosity decay analysis showed that heterozygous alleles decreased with each generation. In the army dog group, if the population number is maintained properly, the frequency of allele genotype will not decrease significantly.

• Asian-Australasian Journal of Animal Sciences
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• v.31 no.11
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• pp.1691-1699
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• 2018

Objective: In Korea, there are three main cattle breeds, which are distinguished by coat color: Brown Hanwoo (BH), Brindle Hanwoo (BRH), and Jeju Black (JB). In this study, we sought to compare the genetic diversity and divergence among there Korean cattle breeds using a BovineHD chip genotyping array. Methods: Sample data were collected from 168 cattle in three populations of BH (48 cattle), BRH (96 cattle), and JB (24 cattle). The single-nucleotide polymorphism (SNP) genotyping was performed using the Illumina BovineHD SNP 777K Bead chip. Results: Heterozygosity, used as a measure of within-breed genetic diversity, was higher in BH (0.293) and BRH (0.296) than in JB (0.266). Linkage disequilibrium decay was more rapid in BH and BRH than in JB, reaching an average $r^2$ value of 0.2 before 26 kb in BH and BRH, whereas the corresponding value was reached before 32 kb in JB. Intra-population, interpopulation, and Fst analyses were used to identify candidate signatures of positive selection in the genome of a domestic Korean cattle population and 48, 11, and 11 loci were detected in the genomic region of the BRH breed, respectively. A Neighbor-Joining phylogenetic tree showed two main groups: a group comprising BH and BRH on one side and a group containing JB on the other. The runs of homozygosity analysis between Korean breeds indicated that the BRH and JB breeds have high inbreeding within breeds compared with BH. An analysis of differentiation based on a high-density SNP chip showed differences between Korean cattle breeds and the closeness of breeds corresponding to the geographic regions where they are evolving. Conclusion: Our results indicate that although the Korean cattle breeds have common features, they also show reliable breed diversity.