斑点叉尾线粒体DNA控制区结构和群体遗传多样性分析  

Structure of mitochondrial DNA control region and population genetic diversity analysis of channel catfish(Ictalurus punctatus)

作　　者：秦钦[1] 许志强[1] 边文冀[1] 王明华[1] 蔡永祥[1] 葛家春[1] 

机构地区：[1]江苏省淡水水产研究所,南京210017

出　　处：《淡水渔业》2011年第4期50-54,共5页Freshwater Fisheries

基　　金：江苏省科技厅项目(BE2008382-1);江苏省水产三项工程项目(P2009-16);全国水产技术推广专项项目

摘　　要：经克隆测序获得了我国5个批次引进的40尾斑点叉尾(Ictalurus punctatus)群体的线粒体控制区全序列,研究控制区序列结构和群体遗传变异。结果显示:比对长度包括906个位点,共有变异位点28个,简约信息位点21个。通过与GenBank中其它鱼类的mtDNA控制区序列进行结构分析,将斑点叉尾的控制区分为终止序列区、中央保守区和保守序列区3个区域;并找到了一系列保守序列:包括终止相关序列TAS,中央保守区的CSB-F、CSB-E、CSB-D和保守序列区的CSB-1、CSB-2、CSB-3。样本总体遗传多样性指数较高,40尾个体含有25个单倍型,其总体单倍型多样性指数(H)为0.92051,总体核苷酸多样性指数(π)为0.00553。各群体遗传多样性分析结果表明,2001群体(2001年出生的群体,下类同)的单倍型多样性指数最高(0.92857),1997群体最低(0.78571)。各群体间的遗传距离较小,其中1999群体与2003群体及2004群体间的遗传距离最大(0.008),1997群体与2001群体间的遗传距离最小(0.003)。1999群体的内部遗传距离较大(0.007),1997群体的内部遗传距离最小(0.003)。5个群体的总体遗传分化指数为0.1075(P<0.001),其中大部分遗传变异存在于各地理群体内部(89.25%),存在于群体间的遗传变异较小(10.75%)。The 40 complete mitochondrial DNA control region sequences of channel catfish（Ictalurus punctatus） from 5 populations introduced into China were sequenced.The structure of the mitochondrial DNA control region sequence and the genetic diversity were studied.The result of sequence alignment showed that there were 28 region variation positions and 21 parsimony informative sites in 906 sites.The mtDNA control region could be partitioned into three domains,i.e.the termination associated sequence domain,the central conserved sequence domain and the conserved sequence block domain;the extended termination associated sequence（ETAS）,three conserved blocks（CSB-F,CSB-E,CSB-D） in the central conserved sequence block domain and three conserved sequence blocks（CSB1,CSB2,CSB3） in the conserved sequence block domain were successfully identified according to their homology to those of other fishes.The genetic diversity index of the total samples was high.25 haplotypes were detected among the 40 samples,with haplotype diversity index（H） of 0.92051 and nucleotide diversity index（π） of 0.00553.Haplotype diversity index of 2001 population（i.e.population that was born in 2001） was the highest（0.92857） and that of 1997 population was the lowest（0.78571） among the 5 populations.The genetic distance between the populations of 1999 and 2003 or 2004 were the farthest（0.008）,and that of 1997 and 2001 was the nearest.The genetic distance within the 1999 population（0.007） was the farthest and that of 1997 population was the nearest.Analysis of molecular variance（AMOVA） showed that genetic differentiation index of all the five populations was 0.1075（P0.001）,of which the majority（89.25%） existed within the population,and the rest existed among the 5 populations（10.75%）.

关 键 词：斑点叉尾(Ictalurus punctatus) 线粒体DNA控制区 遗传多样性 

分 类 号：S917.4[农业科学—水产科学] Q953.5[生物学—动物学]