摘要： 分析中国三种实验用小型猪线粒体DNA（mtDNA）D-loop的多态性，建立各品种品系猪的遗传标记，为各品种、品系猪的鉴别提供依据。应用PCR技术分别对西双版纳近交系小耳猪、广西巴马小型猪、贵州小型香猪和长白猪的血液总DNA样品中mtDNAD-loop进行扩增，用23种限制性内切酶消化，观察其酶切多态。PCR扩增其mtDNAD-loop5′端227bp高变区域，应用PCR?SSCP和PCR直接测序分析，观察其单链构象多态和序列多态。结果显示：三种小型猪之间未见酶切长度多态、单链构象多态和序列多态。与长白猪之间表现出单链构象多态和序列多态。本研究认为：三种实验用小型猪之间mtDNA多态性贫乏，证明其亲源关系很近，在母系起源和进化上有一致性，应用PCR RFLP、PCR SSCP和PCR直接测序分析，尚不能作为三种实验用小型猪品种、品系鉴定的依据，但与长白猪等欧系猪比较有一定差异。
Abstract：the present study is to analyze the polymorphism of the mtDNA D-loop in three breeds of laboratory miniature pigs in China , and to establish its cytoplasmic DNA markers to distinguish among them . The polymorphism of mtDNA D-loop and its 5′-end high variable regions were detected by PCR-RFLP , PCR-SSCP and PCR-direct sequencing on Xishuangbanna Small-ear inbred pig, Guizhou miniature Xiang pig , Guangxi Bama miniature pig and Landrace.There was no polymorphism obtained among or within three breeds of Chinese laboratory miniature pigs besides Landrace. It is concluded that the polymorphism of mtDNA D-loop within the three breeds of Chinese laboratory miniature pigs is poor , These methods cannot be used to distinguish among them , but it can be used to distinguish them from Landrace.