广西和云南树鼩群体遗传多样性的比较分析

Comparison of the genetic diversity between Guangxi and Yunnan tree shrew populations(Tupaia belangeri chinensis)

目的比较分析我国广西、云南两个树鼩群体的遗传差异和分化程度,推动树鼩优良品系的培育和优化实验动物模型。方法提取广西和云南各32只树鼩的全血基因组DNA,分别采用9对荧光标记微卫星引物进行PCR扩增,通过毛细管电泳技术检测扩增片段,并利用POPGENE等软件比较两个树鼩群体的遗传相关指标。结果广西和云南两个树鼩群体平均期望杂合度(He)为0.703,平均多态信息含量(PIC)为0.725,Fis均值>0。CCBL1B、CCDC61、EDA1和OPA3四个位点表现为极显著偏离哈迪-温伯格平衡。两群体的遗传距离及无偏遗传距离分别为1.277和1.268,遗传相似系数约为0.28。遗传结构变异的分布情况显示61.57%的微卫星遗传变异来自于群体内部,38.43%存在于群体之间。STRUCTURE分析发现广西和云南树鼩为中缅树鼩群体的两个不同的亚种。结论广西和云南树鼩两个群体的遗传多样性都较丰富,两个群体间具有较大的遗传差异和分化程度,遗传变异主要来源于群体内部。

Objective To compare and analyze the genetic variation and differentiation of two tree shrew populations from Guangxi and Yunnan,to promote the breeding of fine strains of tree shrews and optimization of experimental animal models. Methods Sixty-four blood samples were collected and the gene DNA was extracted,32 from the Guangxi and 32 from Yunnan populations. PCR amplification products of the nine fluorescent labeling simple sequence repeat（ SSR） markers were detected by capillary electrophoresis technique and various bioinformatics software were used to analyze the genetic diversity of the two tree shrew populations（ Guangxi group and Yunnan group）. PCR amplification was performed using 9 fluorescent-labeled simple sequence repeat（ SSR） markers,the amplification products were detected by capillary electrophoresis technique,and various bioinformatics softwares such as Popgene were applied to analyze the genetic diversity of the two tree shrew populations. Results The average number of expected heterozygosity and polymorphism information content among the 9 microsatellite loci of Guangxi and Yunnan groups were 0. 703 and 0. 725,respectively. The mean value of Fis was 〉0 in both groups. The results of the tests on all the loci with Hardy-Weinberg equilibrium and linkage disequilibrium showed that four loci（ CCBL1 B,CCDC61,EDA1 and OPA3） in the two populations exhibited significant deviations（ P〈0. 001）. The study also found the genetic similarity between the two populations was 0. 28,while the genetic distance and unbiased genetic distance were 1. 277 and 1. 268,respectively. The results from AMOVA analysisshowed that 61. 57% of genetic variation occurred within populations and 38. 43% occurred among populations. Furthermore,structure analysis showed that the Guangxi and Yunnan populations studied in this study are divided into two single subspecies belonging to Tupaia belangeri. Conclusions Our results consistently indicate high genetic diversity of the two tree shrew populations,and their genetic variation is mainly of intra-populational origin.