小尾寒羊PRNP等位基因密码子136、154和171的多态性研究

Polymorphisms of PRNP Alleles in small tail Han sheep

为研究小尾寒羊PRNP等位基因密码子多态性,本研究以绵羊全血基因组DNA为模版,通过PCR,扩增绵羊PRNP等位基因目的片段,并将其克隆于pMD-18T载体。经SSCP法筛选出阳性克隆后测序,确定各绵羊PRNP136位、154位和171位密码子等位基因型及频率分布。在104只绵羊中共检出15个PRNP136位、154位和171位密码子等位基因型,痒病易感基因型占优势(53.85%,56/104)。本研究证明,该绵羊群属于痒病易感/易发群体,一旦痒病传入具有罹患痒病的极大可能性。

The PRNP allelic fragments in Small Tail Han Sheep were amplified by PCR with specific primers and cloned into pMD-18T vector. Positive clones were confirmed by enzymatic digestion, SSCP and sequenced. Fifteen genotypes of PRNP allele at codon 136, 154 and 171 were detected. The high scrapie susceptibility genotypes observed in this breed was 53.85 %. The results showed this flock was a high risk population of the scrapie susceptibility/outbreaks.