Divergent ancestry of Korean native and Thai poultry with independent gene pool retention in Korean commercial chickens.

Abstract

Objective: Korean native chickens (KNCs) are considered as a valuable genetic resource with unique traits; however, the extent of their genetic variation and relationships with other chicken breeds remain underexplored. In this study, we investigated the genetic variation within five KNC varieties: Korean commercial chicken (KOR-C/M), Silkie (KOR-KS), Korean traditional chicken (Gray Brown) (KOR-KGB), Korean traditional chicken (Yellow Brown) (KOR-KYB), and Leghorn (KOR-LH).

Methods: The relationship of KNCs with chicken breeds from Thailand was evaluated using microsatellite genotyping.

Results: High genetic diversity was observed among the KNC breeds, with KOR-KYB showing the highest heterozygosity, whereas KOR-C/M exhibited the lowest heterozygosity and signs of inbreeding. The loci MCW0016, ADL0268, MCW0081, MCW0067, MCW0248, MCW0165, ADL0278, and MCW0330 were identified as being under directional selection. Genetic clustering analyses indicated four distinct clusters, with KOR-C/M differing from other KNC breeds. Distinct gene pools were observed between KNC breeds and indigenous and local chicken populations, as well as red junglefowl in Thailand, suggesting that they have evolved separately. However, connections may exist due to shared ancestry and crossbreeding.

Conclusion: Clustering analysis revealed that KNC breeds formed a separate group from indigenous and local chickens and red junglefowl in Thailand. The distinct genetic patterns suggest independent evolution of the KNC and local Thai breeds, although shared ancestry and crossbreeding may have introduced some connections. These findings have significant implications for the conservation and sustainable management of KNC populations.