小尾寒羊遗传共适应的初步研究

Preliminary Study on Genetic Co-adaptation of Small-tailed Han Sheep

以中心产区小尾寒羊编码碱性磷酸酶(Alp)、酯酶(Ary-Es)、亮氨酸氨肽酶(Lap)、血红蛋白β链(Hb-β)、苹果酸脱氢酶(ME)、过氧化氢酶(Cat)6个多态结构基因座上的频率分布为研究对象,进行遗传共适应分析,结果表明:(1)显隐性-显隐性和显隐性-共显性组合座位均处于遗传平衡状态,共显性-共显性组合座位中ME/Cat处于遗传不平衡状态;(2)Hb-β/ME座位间遗传共适应起着与连锁不平衡相反的作用;ME/Cat座位间遗传共适应的独立作用造成其遗传不平衡;(3)遗传不平衡系数、连锁不平衡系数和配子间遗传共适应概率与x2适合性检验结果相一致。

Genetic co-adaptation of Small-tailed Han sheep in central area of habitat was studied on the basis of 6 polymorphic structural gene loci encoding alkaline phosphatase (Alp), arylesterase (Ary-Es), leucine aminopeptidase (Lap), hemoglobin-β(Hb-β), malate dehydrogenase (ME) and catalase (Cat). The results were as follows: (1) Combination loci in the models of dominance-dominance and dominance-Co-dominance were all in the condition of genetic equilibrium, while combination loci ME/Cat in the model of co-dominance-co-dominance was in the state of genetic disequilibrium. (2) Genetic co-adaptation acted against linkage disequilibrium between Hb-β and ME loci, the single action of genetic co-adaptation between ME and Cat caused its genetic disequilibrium. (3) The coefficients of genetic disequilibrium, linkage disequilibrium and the probability of genetic co-adaptation between gametes corresponded to the conclusions drown from chi-squared tests of goodness-of-fit.