三江白猪线粒体DNA的多态性

采用22种限制性内切酶分析了三江白猪mtDNA多态性。在60头个体中检出30种限制性态型，归结为7种基因单倍型；其间的差异来自少数限制性位点的突变。单倍型间平均遗传距离为0．35％，群体遗传多态程度为0．044％。三江白猪遗传多样性非常贫乏，说明三江白猪与地方种猪起源于一个共同祖先，在品种形成早期受到创立者效应的制约。

The Polymorphism of Mitochondrial DNA in Sanjiang White Pig

A total of 22 restriction endonucleases were used to investigate the mitochondrial DNA polymorphism of Sanjiang white pigs. Thirty restrictive morphs were detected, which can be sorted into 7 haplotypes. The differences between haplotypes came from several dots mutation. The average genetic distance among haplotypes is 0 35%, and the value of average sequence variation in Sanjiang White pigs population is 0 044%.The results indicate that the genetic diversity based on restriction endonuclease cleavage patterns within Sanjiang white pigs is remarkably scarce. They may have originated from a late common ancestor, and are likely impacted by the founder effect.