Abstract Estimating the genetic diversity and origins is critical for the identification and conservation of valuable animal genetic resources. Mitochondrial DNA (mtDNA) polymorphisms have played a significant role in tracing the origin of specific breeds and the genetic diversity of domestic chicken and other livestock species due to their maternal inheritance, greater rate of substitution relative to unclear genes, and much lower rate of recombination. In this study, we analyzed the mtDNA D-loop region of 457 genomic DNA samples from 28 Asian chicken populations (Korea: 6, Laos: 4, Bangladesh: 3, Cambodia: 3, Indonesia: 3, Vietnam: 2, Kyrgyzstan: 1, Mongolia: 1, Nepal: 1, Sri Lanka: 1 and White Leghorn, Cornish, Rhode Island Red) from ten Asian countries to clarify their genetic diversity and phylogenetic relationships. In addition, 49 reference data (43: Oka et al data, 6: red jungle fowl) were used. We found 82 haplotypes defined by 81 variable sites. Overall haplotype and nucleotide diversity were 0.978±0.01 and 0.0018, respectively. Phylogenetic analyses revealed seven haplogroups (Type A-G). The most of Asian chickens were included in haplogroup A(44.9%), B(22.8%), C(19.3%). Haplogroup F did not belong to any Asian chicken populations (include only 2 reference data). Mongolia chickens were only clustered in haplogroup A and Indonesian chickens did only haplogroup C. About half of Kyrgyzstani chicken populations (43.4%) were clustered in haplogroup E. Vietnamese chicken populations belong to all haplogroup except F. In case of red jungle fowl, G.g.gallus and G.g.bankiva were clustered in haplogroup C. G.g.spadiceus was clusterd in haplogroup E or A. As a result, it was possible to identify the mtDNA diversity and origin of Asian chicken populations. In future studies, it is necessary to understand the origin of each haplogroup by adding more reference data and red jungle fowl sequence data.
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