Mitochondrial DNA D-loop genetic diversity and multiple maternal origins in Mongolian horses

[Objective] The study was to detect the genetic diversity and origin of Mongolian horses,mitochondrial DNA of 247 bp from Mongolian horses was analyzed.[Method] 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.[Result] 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.[Conclusion] 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.