Genetic Variation and Phyletic Evolution of Xin'anjiang Buffalo Based on Mitochondrial DNA D-Loop
The objectives of this study were to investigate molecular genetic characteristics of Xin'anjiang buffalo in the upper reaches of Xin'an River basin of Huangshan city from Anhui province,and explore the maternal origin and genetic diversity.The mtDNA D-Loop sequences of 28 Xin'anjiang buffalo were sampled and determined by PCR amplification and sequencing.693 D-Loop sequences of 24 Chinese buffalo were downloaded from GenBank database.Genetic bioinformatics were used to analyze genetic diversity,construct Neighbor-joining tree and Media-joining network,and explore the distance between populations.The results showed that 117 nucleotide polymorphic sites and 25 haplotypes were identified in Xin'anjiang buffalo population,the estimated overall nucleotide diversity and haplotype diversity were 0.026 02±0.003 03 and 0.989±0.014,respectively.Genetic variation of Xin'anjiang buffalo was similar to other buffalo populations.The Neighbor-joining tree indicated that the 25 haplotypes of Xin'anjiang buffalo were divided into A and B lines,with 2 maternal sources,of which A was dominant.The Media-joining evolutionary network showed that Chinese buffalo were mainly swamp buffalo,including A and B lines,and the B line could be further divided into sub-lineages of b1 and b2.In summary,there was rich mitochondrial genetic diversity in Xin'anjiang buffalo population,and it was similar to other buffaloes in China;the Xin'anjiang buffalo was a swamp buffalo with two mitochondrial maternal sources,which had a certain genetic distance from other buffalo populations in China.