Abstract: Objective Providing valuable information and references for standardization of Kunming mice by detecting and analyzing genetic profiles, genetic variation and genetic differentiation of Kunming mice populations. Methods 15 microsatellite markers were screened by a fluorescence-based semi-automated genotyping method for the 3 populations of Kunming mice, BJ(population of Kunming mice maintained at the Rodent Laboratory Animal Resources in Beijing),SH(population of Kunming mice maintained at the Rodent Laboratory Animal Resources, Shanghai branch) and F1(Hybrid population between SH and population from the First Biochemical-pharmaceutical Factory of Shanghai), and genetic variation of each population and genetic diversities between populations were evaluated. Results A total of 92 alleles were detected in the 3 populations, with 2～13 and mean 6.13 at each locus, and the mean unbiased expected heterozygosity was 0.5721, which implies that there is abundant genetic variation in the populations of Kunming mice. 61, 63 and 51 alleles were detected, and mean unbiased expected heterozygosity were 0.4923, 0.5177 and 0.4550 in population BJ, SH and F1, respectively. It suggested that slightly more polymorphisms were detected in population SH than in population BJ and less polymorphism were detected in population F1. The most, 43 shared alleles, were detected between population SH and F1, which suggested low genetic differentiation between them. 37 alleles were detected between population BJ and SH, and 32 alleles were detected between population BJ and F1, which suggested high genetic differentiation. Poor genetic differentiation was discovered between SH and F1 with the mean Fst being 0.0222 and Nei's unbiased measures of genetic distance estimates being 0.0279; moderate genetic differentiation was discovered between BJ and SH with the mean Fst being 0.1433 and Nei's unbiased measures of genetic distance estimates being 0.3881; large genetic differentiation was discovered between BJ and F1 with the mean Fst being 0.1667 and Nei's unbiased measures of genetic distance estimates being 0.4162. Population SH was clustered with population F1 firstly, which were clustered with population BJ then by UPGMA method. Conclusion Genetic profiles of 3 Kunming mice were identified by 15 microsatellite loci, and moderate or large genetic differences between populations from different keepers were validated, and loss of alleles should be avoided during hybridization between populations for standardization of Kunming mice. The present study could provide valuable information and references for establish standard population of Kunming mice and genetic monitoring for it.

Key words: Kunming mice, Microsatellite, Outbred colony, Genetics

摘要： 目的检测和分析我国主要昆明小鼠群体的遗传背景、遗传多样性及其遗传分离情况,为建立标准化昆明小鼠种群及其遗传背景建立和监测提供基础资料。方法应用筛选获得的15个微卫星标记及其荧光标记-半自动基因分型技术,对我国国家啮齿类实验动物种子中心(北京种群)、国家啮齿类实验动物种子中心上海分中心(上海种群)、国家啮齿类实验动物种子中心上海分中心与上海第一生化制药厂的融合F1代(融合种群)昆明小鼠种群进行遗传检测和分析,评估各群体的遗传背景、遗传多样性、群体间的遗传关系及进行品系融合后的遗传学变化。结果3个昆明小鼠种群在15个微卫星位点共检测到92个等位基因,每位点2～13个,平均6.13个;平均期望杂合度为0.5721,表明昆明小鼠具有较好的遗传多样性。北京种群、上海种群、融合种群分别检测到61、63、51个等位基因,其在15个微卫星位点的平均期望杂合度分别为0.4923、0.5177、0.4550,表明上海种群的遗传多样性略大于北京种群,融合种群的遗传多样性低于北京和上海种群。从等位基因组成上看,上海种群与融合种群共有基因数最多(43个),表明其较小的遗传差异;而北京种群和上海种群(37个)、北京种群和融合种群(32个)的共有基因数均明显少于上海种群和融合种群间的共有基因,表明北京种群和上海种群及融合种群间较大的遗传差异。群体间遗传变异分析表明,上海种群和融合种群间的遗传分化程度很弱,其Fst值为0.0222,遗传距离为0.0279;北京种群和上海种群遗传分化为中等,其Fst值为0.1433,遗传距离为0.3881;北京种群与融合种群间有较大遗传分化程度,其Fst值为0.1667,遗传距离为0.4162;根据Nei遗传距离进行UPGMA系统聚类表明上海种群和融合种群先聚为一类,再与北京种群聚为一类。结论利用15个微卫星标记,初步确定了3个昆明小鼠群体的遗传背景,从分子水平表明不同生产单位的昆明小鼠种群间具有中等或较大的遗传分化程度,种群融合过程中应采取适当措施避免封闭群遗传基因的丢失从而造成遗传多样性减少,研究结果为建立标准化昆明小鼠种群及其遗传背景建立和监测提供了基础资料。

关键词: 昆明小鼠, 微卫星, 封闭群