基于线粒体基因的杂色山雀中国大陆种群遗传多样性研究

The Genetic Diversity Research of Parus Varius in China's Mainland Based on Mitochondrial Gene

杂色山雀(Parus varius)为东亚特有鸟类、分布呈片段化.为了深入了解杂色山雀中国大陆各地理种群遗传水平现状,分析了杂色山雀8个地方种群49个样本的线粒体Cytb基因全序列(1143bp)和部分ND5基因序列(957 bp),所测样品全长共2.1 kb.结果显示:T、C、A、G碱基的平均含量分别为21.5%、37.4%、28.9%、12.2%,A+T含量(50.4%)略高于G+C含量(49.6%);发现17个变异位点,其中单变异位点为7个,简约信息位点数为10个;检测到14个单倍型,8个地方种群共享一个单倍型(Hap-1),说明这个单倍型是个较古老的单倍型,也反映了这几个群体间的分化是不显著的.5个种群的单倍型多样性为0.822 39,核苷酸多样性为0.000 82,平均核苷酸差异数为4.663 83,总体上看,杂色山雀具有较低的单倍型多样性和核苷酸多样性.五个种群的Nm值为5.282 21～17.336 45,Fst值为0.002 07～0.086 47,构建的系统发生树和TCS网络图进一步分析表明杂色山雀遗传多样性较低、基因交流非常频繁、种群间的分化不显著.中性检验显示偏离中性期望值,表明种群在进化的过程中出现过群体急速扩张事件.

Parus varius(Paridae Passeriformes) is one of the species with obvious rupture and narrow distribution,which only distributed in east Asia.To better understand the genetic variation level of different geographic group of Parus varius in China's Mainland,we analyzed the whole mitochondrial Cytb gene sequence(1143bp) and part of the ND5 gene sequence(957bp) in fortynine samples among eight geographic populations.The average length of tested samples is about2100 base pairs.Our result show that the base content for T,C,A and G bases were 21.5%,37.4%,28.9%,12.2%,respectively.The base content for A + T(50.4%) was a little more than that of G + C bases(49.6%).We found 17 genetic variation sites in which the single variation sites were 7 and parsimony-informative sites were 10.Moreover,14 haplotypes were detected,eight geographic populations share the same haplotype(Hap-1),which indicates this haplotype is an ancient one,reflecting that the genetic differentiation among them was not significant.The nucleotide diversity and the haplotype diversity of five geographic groups were 0.822 39 and0.000 82,respectively.The average number of nucleotide differences of them is 4.663 83.Overall,Parus varius has a lower haplotype diversity and nucleotide diversity.The Nm value of five geographic groups is 5.282 21 ～ 17.336 45 and the Fst value of them is 0.002 07 ～ 0.086 47.The results of phylogenetic and TCS network analysis further indicated that the genetic diversity of Parus varius was lower,gene flow of Parus varius was very frequent and the differentiation among the populations was not significant.The result of neutral test was deviated from neutral mutation,which could confer that the population expansion had ever happened in Parus varius evolution history.