兰州大尾羊血液蛋白多态性研究

Study on Polymorphisms of Blood Proteins in Lanzhou Fat-tailed Sheep

为了探明兰州大尾羊的种质和遗传特性,采用聚丙烯酰胺凝胶水平板电泳,检测了131只兰州大尾羊血红蛋白、白蛋白、后白蛋白、转铁蛋白、慢-a2-球蛋白、血清淀粉酶、酯酶、苹果酸脱氢酶的多态性.结果发现,除白蛋白和慢-a2-球蛋白未表现出多态外,其他各蛋白质和酶均不同程度地呈现出多态,其中血红蛋白、后白蛋白、血清淀粉酶、酯酶、苹果酸脱氢酶各有2个等位基因,3种基因型;兰州大尾羊的平均基因杂合度为0.480 2,等位基因有效数为1.924,多态座位百分比为0.75.对Nei氏标准遗传距离进行聚类,发现兰州大尾羊与滩羊最近,其次为大尾寒羊和小尾寒羊.青海细毛羊、滩羊、兰州大尾羊、青海藏羊、考湖羊、河北杂种细毛羊、新疆细毛羊、罗姆尼半细毛羊、大尾寒羊、小尾寒羊、兰州大尾羊等11个绵羊品种的基因分化系数为0.079 36,这表明中国的绵羊品种的遗传变异性的92.064%是由遗传多态现象引起的,而7.936%来自品种间差异,即中国绵羊在血液蛋白质水平上的遗传分化程度不高.

An investigation was undertaken to clarify the polymorphisms of blood proteins and enzymes of 131 Lanzhou fat-tailed sheep by polyacrylamide gel electrophoresis method.The results showed that there were two alleles and three genotypes at the loci of Hb, Po, Amy, Es and MDH and seven alleles and fourteen genotypes at the loci of Tf and Albumin (Alb) and slow-a2-macroglobulin were monomorphic.The average gene heterozygosity(H) of Lanzhou fat-tailed sheep was 0.480 2 and the number of effective alleles(Ne) was 1.924, the proportion of polymorphisms (Ppoly) was 0.75.Hwas higher compared with other breeds in China.By the shortest distance method based on the Nei抯, the cluster result showed that the blood relationship between Lanzhou fat-tailed sheep and tan-yang sheep was the closest and then followed by the relationship between Lanzhou fat-tailed sheep and fat-tailed han-yang or thin-tailed han-yang. The coefficient of genetic divergence among the eleven sheep breeds in China was 0.079 36.This indicated that 92.064% of genetic variations resulted from the genetic polymorphisms within breeds and 7.936% was caused by the difference among breeds in China.