Phylogenetic Relationships among Dabbling Duck Species in Korea using COI Gene Variations in mtDNA

Korea is an important geographical location for wintering dabbling ducks. In order to investigate their relationships, 92 ducks from ten breeds were sampled from nine different geographical areas in Korea. Of these, 38 samples are represented as Mallard (Anas platyrhynchos), Spot-billed (Anas poecilorhyncha zonorhyncha) and domestic (Anus platyrhynchos domesticus) ducks. They are very closely related to commercial duck breeds. The partial (746 and 749 bp) mitochondrial DNA (mtDNA) COI (Cytochrome Oxidase I) gene sequences were obtained and 126 SNPs were identified, which belong to 23 haplotypes. Eighty five Anas and ten Aix genus have been used for phylogenetic analysis. Based on the neighbor-joining (NJ) method, duck species used in this study can be well differentiated, except for the three duck breeds, Mallard, Spot-billed and domestic ducks, where most of the individuals belong to haplotype 12. The highest K2P distance, 0.31, was observed in Spot-billed ducks, with a range of 0.07-10.96 between the species. However, there was no correlation between geographic distance (km) and K2P distance (%) between the species. Based on our results, duck species can be discriminated with COI sequences, except for the three closely related breeds, and this can be effectively used for an appropriate conservation program for the wild duck breeds in Korea.