山东3个绵羊品种线粒体细胞色素b基因的系统进化研究

本文测定了小尾寒羊、大尾寒羊、洼地绵羊共3个品种部分线粒体DNA细胞色素b 基因片段,并以鲁北白山羊为外群,应用NJ法构建分子系统树。结果显示: 44 个位点检出变异,绵羊群体变异度为0.0102,线粒体DNA多态性相对贫乏,推测3个品种具有共同母系祖先;洼地绵羊与大尾寒羊关系较近,与小尾寒羊亲缘关系最远。

Phylogenetic Relationships of Three Native Sheep Breeds in Shandong Based on Mitochondrial Cytochrome b Gene Sequences

In this study ,fragments of mitochondrial DNA cytochrome b gene (each 415 base pairs in length) have been characterized from Little-tailed sheep, Large-tailed sheep, Wadi sheep and Lubei White goat by sequencing of the recombinant plasmids, of which 44 variable sites were identified after combining and aligning the data with the homologous sequence. And the value of average sequence variation in sheep population (π) is 3.13%. Our results suggest that the genetic diversity within the sheep is remarkably scarce and these sheep breeds may have originated from a late common ancestor. Phylogenetic trees were constructed with neighbor joining method with the Lubei White goat as outgroup The phylogenetic relationships of mitochondrial DNA suggested that Wadi sheep be more closely related with Large-tailed sheep breeds.