河南斗鸡线粒体D-loop区多态性及与4种斗鸡的进化分析

对28只河南斗鸡线粒体基因组(mitochondrial genome,mt DNA)D-loop区全序列进行PCR扩增和测序,并结合Gen Bank中其他品种中国斗鸡D-loop区序列,进行序列比对和进化分析。结果发现,河南斗鸡mt DNA D-loop区全长1232 bp,单倍型多样性(Hd)为(0.542±0.086),核苷酸多样性(Pi)为(0.00236±0.00083),共发现9处单核苷酸多态位点,3种单倍型。品种间进化分歧显示,河南斗鸡和西双版纳斗鸡遗传距离最近(0.0095),与漳州斗鸡遗传距离最远(0.0226)。系统发育分析发现,5个斗鸡品种可以分成A、B、C、D和E 5个分支。研究表明,河南斗鸡mt DNA D-loop区呈中度多态,有2个母系起源,本研究可以为河南斗鸡的遗传资源保护和选育提供一定参考。

Mitochondrial DNA control region polymorphisms in Henan Gamecocks and evolutionary relatedness with other four Gamecock breeds

To determine the origin and genetic diversity of Henan Gamecocks, blood samples were collected from 28 chickens, and the complete mtDNA D-loop was amplified by PCR and sequenced subsequently. DNA sequences of mtDNA D-loop of four gamecock breeds were collected from the GenBank and used as the reference sequences. The results showed that the D-loop region of Henan Gamecocks was 1232 bp in length. The haplotype diversity was 0.542, and the nucleotide diversity was 0.00236. The 3 haplotypes were observed based on 9 mutant sites. Estimates of evolutionary divergence between breeds showed that the Henan Gamecocks was genetically closest to the Xishuangbanna Gamecocks (0.0095) and farthest to Zhangzhou Gamecocks (0.0226). Five original clades (A, B, C, D and E) were found among five gamecock breeds using a neighbor-joining phylogeny. It is concluded that the Henan Gamecocks are moderately genetically diverse and have two maternal origins. The genetic structure of Henan Gamecocks in China might be influenced by the subsequent breed selection and conservation after the initial gamecock introduction.