title: Mitochondrial DNA diversity and the origin of Chinese indigenous sheep.
abstract: Large-scale mitochondrial DNA (mtDNA) D-loop sequences data from previous studies were investigated to obtain genetic information which contributes to a better understanding of the genetic diversity and history of modern sheep. In this study, we analyzed mtDNA D-loop sequences of 963 individuals from 16 Chinese indigenous breeds that distributed seven geographic regions. Phylogenetic analysis showed that all three previously defined haplogroups A, B, and C were found in all breeds among different regions except in Southwest China mountainous region, which had only the A and B haplogroups. The weak phylogeographic structure was observed among Chinese indigenous sheep breeds distribution regions and this could be attributable to long-term strong gene flow among regions induced by the human migration, commercial trade, and extensive transport of sheep. The estimation of demographic parameters from mismatch analyses showed that haplogroups A and B had at least one demographic expansion of indigenous sheep in China.
authors.affiliation: College of Animal Science and Technology, Chongqing Key Laboratory of Forage & Herbivore, Chongqing Engineering Research Centre for Herbivores Resource Protection and Utilization, Southwest University, Beibei, Chongqing, 400716, China.
authors.forename: Erhu
authors.initials: E
authors.lastname: Zhao
authors.forename: Qian
authors.initials: Q
authors.lastname: Yu
authors.forename: Nanyang
authors.initials: N
authors.lastname: Zhang
authors.forename: Deying
authors.initials: D
authors.lastname: Kong
authors.forename: Yongju
authors.initials: Y
authors.lastname: Zhao
mesh_terms: D000818:Animals; D002681:China; D004272:DNA, Mitochondrial / Q000235:genetics*; D019143:Evolution, Molecular; D014644:Genetic Variation; D006239:Haplotypes; D010802:Phylogeny; D012756:Sheep / Q000145:classification* / Q000235:genetics*
chemical_list: D004272:DNA, Mitochondrial