绵羊TLR4基因的遗传多态性分析

摘要

To analyze the polymorphism and variation characteristics of TLR4 gene in four kinds of sheep( Yongchang sheep , Small-tail Han sheep ,White Suffolk sheep and Texel sheep), Part of TLR4 genes exon 3 were amplified in 404 sheep using PCR-single stranded conformational polymorphism ( PCR-SSCP) analysis. Seven genotypes controlled by six al-leles were detected. Alleles E and F were indectectable in Yongchang sheep,White Suffolk sheep and Texel sheep, and al-leles D was not detected in Small-tail Han sheep. Nineteen nucleotide polymorphism or nine amino acids polymorphic locis were identified in TLR4 gene. Chi-square test indicated that the polymorphic loci in four breeds were all in Hardy-Weinberg equilibrium(P0. 50).%为了研究永昌羊、小尾寒羊、白萨福克羊和特克塞尔羊4个品种的舍饲绵羊TLR4基因的遗传多态性及变异特征,采用PCR-SSCP方法,检测这4种绵羊(共404只) TLR4基因第3外显子部分基因片段的多态性以及产生变异的各等位基因序列。结果显示,4种绵羊中共发现6种等位基因控制的7种基因型,永昌羊、白萨福克羊和特克塞尔羊均未检测到E和F等位基因,小尾寒羊未检测到D等位基因；与 GenBank 中羊TLR4基因序列比对发现,扩增片段中有19个核苷酸多态位点,编码的氨基酸序列中有9个氨基酸多态位点；经χ2适应性检验,4个绵羊品种均位于 Hardy-Weinberg 平衡( P>0.05),其中白萨福克羊、特克塞尔羊和小尾寒羊处于高度多态( PIC>0.50),而永昌羊处于中度多态(0.25