Complete mitogenome structure and phylogenetic implications of the first Indian yak breed- Arunachali (Poephagus grunniens L.)

Abstract

Arunachali is the first registered breed of yak in India inhabiting Tawang and West Kameng districts of Arunachal Pradesh. Arunachali yak breed accounts for half the yak population in India, however, the number has been declining. In order to conserve and propagate this majestic and unique animal, this study reports the first ever whole mitogenome of an Indian yak breed. The mitogenome of Arunachali yak was found to be circular and double stranded with a length of 16,324 bp comprising 13 protein coding genes (PCGs), 22 tRNAs, 2 rRNAs and an 894bp non-coding control region (D-loop). Out of the 37 genes, 29 genes were encoded on H-strand and 8 on the L-strand. The overall nucleotide composition was A = 33.70%, T = 27.28%, G = 13.21% and C = 25.80% with an AT biasness. Phylogenetic analysis was done with three datasets involving 27 whole mitogenome of Chinese yak breeds and a Bos indicus outgroup sequence. The Arunachali yak shows same ancestry with the other yak breeds and more closeness to Jinchuan yak based on D-loop sequence. The findings of this study elucidate the mitochondrial genomic architecture of Arunachali yak and its evolutionary status along with providing basis for characterisation and formulation of specific breeding policies for Indian yaks.