Mitochondrial DNA D-loop genetic diversity and multiple maternal origins in Mongolian horses | 蒙古马mtDNA D-loop区遗传多样性与多重母系起源

Chinese. 对蒙古马mtDNA D-loop区247 bp序列进行遗传多样性分析，探讨蒙古马的起源。采用PCR方法、测序技术及生物信息学方法,将本试验所测得的21匹蒙古马的mtDNA D-loop区序列，与GenBank中公布的43条蒙古马的对应序列，及世界范围内家马、普氏野马和内蒙古地区古马的mtDNA D-loop区序列一起进行系统发育分析。蒙古马具有39种单倍型，37个多态位点，核苷酸多样度(π) 为0.027 56±0.009 67, 单倍型多样度(h)为0.979±0.007，表明蒙古马mtDNA 遗传多样性非常丰富。引用世界家马、古马、普氏野马和蒙古马共1 074条mtDNA D-loop序列及本研究中21条mtDNA D-loop序列，共同进行系统发育分析，结果显示，蒙古马分布于A、B、C、D、E和F支系。蒙古马为多重母系起源，且与国内古马的母系起源几乎一致，推测蒙古马可能是中国北方家马的重要母系来源。

English. The study was to detect the genetic diversity and origin of Mongolian horses, mitochondrial DNA of 247 bp from Mongolian horses was analyzed. Mitochondrial D-loop sequences of 247 bp from 21 Mongolian horse samples, together with data available from GenBank including 43 Mongolian horses, horses across the world, Przewalskii and ancient horse of Inner Mongolian Region were analyzed by PCR, sequencing and bioinformatics methods. The results revealed that a total of 39 haplotypes with 37 polymorphic sites were found in 64 D-loop sequences of Mongolian horses. The nucleotide diversity (π) and haplotype diversity (h) estimated were 0.027 56±0.009 67 and 0.979±0.007, respectively, showing rich mitochondrial genetic diversity in Mongolian horses. Phylogenetic analysis based on the published domestic horse, Przewalskii, Mongolian horses and ancient horse sequences collected from GenBank, revealed that Mongolian horses fall into lineages A, B, C, D, E and F. Mongolian horses demonstrated multiple maternal origins, which is almost consistent with that of ancient Chinese horses. Mongolian horses might play important roles in the origins of domestic horses in Northern China.