凉地方牛群体母系遗传背景研究

黄牛（Bos taurus）的驯养作为农耕文化重要内容之一，在我国历史悠久，长久以来形成的役用型逐步被肉用型所替代。为了揭示平凉地方牛群体的遗传背景，分析其是否具有生产优质牛肉的遗传基础，本研究测定了88头平凉地方牛群体mtDNA D-loop HVS序列，并对包括平凉地方牛群体在内的我国23个地方牛群体单倍型分布及系统发生关系进行了分析。结果表明，mtDNA D-loop 高变区，在平凉地方牛群体共有52个单倍型，而23个地方牛群体共有95个单倍型，这些单倍型在系统发生树和中介网络关系中分布于两个分枝，即瘤牛型和普通牛进化枝。因此，我们认为平凉地方牛群体和我国其他牛种一样，存在普通牛和瘤牛两个母系起源的遗传背景。

Study on Maternal Genetic Background of Pingliang Native Cattle

Domestication of cattle, one of the important content in farming culture, has a long history in China. The objectives of the study were to reveal the maternal genetic background of Pingliang native cattle and to assess its potential to be improved into a high quality beef genotype. A total of 88 Pingliang native cattle were sequenced for their mtDNA D-loop HVS region. The haplotypes and phylogenetic relationship of 23 Chinese local cattle population including Pingliang cattle were jointly analyzed. Ninety five haplotypes were identified and distributed into the two major phylgenetic groups reconstructed following phylogenetic and network analyses, representing the distinct mtDNA genomes of Bos taurus or Bos indicus cattle. Pingliang native cattle were derived from these two maternal genetic backgrounds, which may have migrated and expand into the Central China following different introductions from north and south for the taurine cattle and from south to north for the zebuine cattle while a movement from west to east was observed for both cattle genetic backgrounds, and Pingling cattle was distributed into both of maternal genetic backgrounds.