Identification of genetic polymorphisms in bovine mitochondrial deoxyribonucleic acid.

In this study, the intent was to identify genetic polymorphisms of mitochondrial (mt) DNA in Korean cattle (Bos taurus coreana) and to analyze the genetic relationship between Korean cattle and other breeds. Whole mtDNA genomes (16,338 bp) of 26 animals (16 Korean cattle and 10 Holsteins) were directly sequenced. Multiple alignments, including 26 whole-mtDNA sequences obtained by direct sequencing and 10 mtDNA sequences from a public database (National Center for Biotechnology Information), revealed 393 mtDNA polymorphisms (382 SNP, 3 heteroplasmies, and 8 insertion-deletion polymorphisms). Estimated gene diversity of mtDNA was 0.00198 among these 36 animals. Phylogenic analysis with mtDNA polymorphisms revealed a distinct genetic difference between Bos taurus (Korean, Japanese Black, Holstein, and Fleckvieh breeds) and Bos indicus (Nellore and Zwergzebu breeds). The genetic information regarding mtDNA polymorphisms identified in this study would be useful for further investigation of mtDNA in other breeds.