随机留种下闭锁群体近交系数和基因杂合度的世代变化  

Changes of Inbreeding Coefficient and Genic Heterozygosity in Closed Population under Random Selection

作　　者：鲁绍雄[1] 毛华明[1] 鲁立刚[1] 连林生[1] 

机构地区：[1]云南农业大学动物科学技术学院,昆明650201

出　　处：《中国畜牧兽医》2010年第5期151-154,共4页China Animal Husbandry & Veterinary Medicine

基　　金：国家863计划重点项目(2008AA101001)

摘　　要：在假定不发生基因突变、群体间无个体迁移的情况下,采用MonteCarlo计算机模拟方法模拟了不同群体规模、性别比例和初始基因频率下闭锁群体近交系数和基因杂合度的变化。10个双等位基因座位分别位于10条不同的常染色体上,群体内实行随机留种,随机交配,世代不重叠,且每代参与繁殖的个体数相同。模拟试验共进行了50个世代,100次重复。结果表明,群体规模较大、公畜数较多时,群体近交系数上升缓慢,基因杂合度较高;当初始基因频率处于中等水平时,群体内可保持较高的基因杂合度;群体规模太小、公畜比例过低及基因的初始频率过低或过高,均不利于群体内遗传多样性的保持。Monte Carlo computer simulation was used to determine the changes of inbreeding coefficients and genic heterozygosities in closed populations under different population sizes,male-female ratios and initial gene frequencies,which assumed that there was no gene mutation and individual immigration between populations. 10 bi-allelic gene loci were assumed on 10 different autosomes. Random selection and mating was implemented in all generations,the generation was non-overlapping and the numbers of breeding animals were kept equal in each generation. The simulation experiment had been carried out for 50 generations and 100 replications. The results showed that the smaller inbreeding increments and higher genic heterozygosity were gained for larger size population and more males; and the higher heterozygosity had been kept under medium level initial gene frequency. It was harmful for the maintaining of the within-population genetic diversity for smaller population,fewer males and lower or higher initial gene frequency.

关 键 词：闭锁群体 随机留种 近交系数 基因杂合度 计算机模拟 

分 类 号：S813[农业科学—畜牧学]