11个猪品种生长激素(pGH)基因多态性及其遗传分化研究

利用PCR和测序技术,检测了11个猪品种共65个个体的生长激素(pGH)基因全序列多态性,发现43个SNPs和1个位于内含子3的7 bp缺失片段。分析结果表明,pGH基因DNA序列不同功能区变异程度各不相同,外显子区、内含子区、5′和3′端非编码区SNPs位点各占SNPs位点总数的18.60%、74.42%、6.98%;外显子区8个SNPs位点导致4个氨基酸位点变异,外显子2是编码区的高变域;各SNPs的变异属典型的中性突变;不同品种有其独特的单倍型。分子方差分析(AMOVA)结果表明,pGH基因DNA序列品种内的变异(方差比率73.45%)大于品种间的变异(方差比率26.55%),品种间差异极显著(P<0.01),存在较明显的遗传分化;pGH基因自身进化及品种进化主要体现在内含子区,品种间的遗传分化与地理分布和基因交流有关。

Study on Polymorphism and Genetic Differentiation of pGH Gene in 11 Pig Breeds

By applying PCR and sequencing technique,the polymorphism and genetic differentiation of porcine growth hormone gene in 65 individuals form 11 pig breeds were studied.43 SNPs loci and 7 bp lack segment within intron 3 were found.Analysis results showed that the variance is different at different function region.The percentage of SNPs loci in exon region,intron region and 5'-UTR and 3'-UTR region are 18.60%,74.42% and 6.98%.There are 8 SNPs loci in exon region which bring about 4 amino acid loci variation,exon 2 is the high variation region.The variance of SNPs loci belongs to neutral mutation.The pGH gene haplotype among 11 breeds is unique.Results of AMOVA analysis showed that the variation of pGH gene sequence is higher in interbreeds(Percentage of variation is 73.45%) than interbreeds(Percentage of variation is 26.55%),the diversity among breeds is significant at 0.01,and the genetic differentiation of pGH gene is significant.The main favorable factor affecting pGH gene evolution and breeds genetic differentiation is intron region.The genetic differentiation among breeds is related to gene flow and geographic distribution.