Diversity and phylogenetic analysis of the cyt b gene of three Chinese bovid species

Genetic diversity and phylogenetic relationships of Chinese yellow cattle,yak and buffalo were analyzed based on DNA sequences of the cytochrome b gene.The content of A/T was comparatively higher in sequences of the cyt b gene of yellow cattle,yak and buffalo,compromising 56.6%,58.2% and 56.0% of the total nucleotides on average respectively.The nucleotide diversity of the cyt b gene of Yellow cattle was higher(Pi=0.016 84) than that of yak(Pi=0.012 28) and buffalo(Pi=0.003 51).Phylogenetic tree of the cyt b gene haplotypes among three bovid species was constructed by using Neighbor-joining algorithms.The results indicated that the phylogenetic relationship of Yellow cattle and yak was comparatively closer than that of yellow cattle and buffalo.Yellow cattle showed closer phylogenetic relationship to European bison and were originated from Bos taurus and Bos indicus,while Yak showed closer relationship with Bos javanicus and Bos gaurus.The three individuals of Chinese buffalo examined were phylogenetically related to Bubalus bubalis and fell into two distinctive clades in maternal lineage.