利用微卫星标记对文蛤4个壳色花纹品系的遗传分析

利用9个微卫星位点对文蛤红壳(RS)、黑斑(BS)、细纹(TC)、暗纹(DF)4个壳色花纹品系共120个个体进行遗传差异分析。结果共检测到105个等位基因,每个位点平均观察等位基因数为11.7个,其中WG07位点等位基因数最多(21个),WG11位点最少(7个)。每个品系均具有特异等位基因类型,不同品系中相同微卫星位点的等位基因分布规律不同。4个文蛤品系的观测杂合度、期望杂合度和多态信息含量变异范围分别为0.110～1.000、0.486～0.867、0.433～0.834,均属高度多态性位点。Hardy-Weinberg平衡的卡方检测发现,大多数位点偏离平衡状态;聚类分析表明,4个品系间存在较明显的遗传差异,TC品系与其它品系的遗传距离最大,DF品系和RS品系的遗传距离相对较小。

Genetic analysis among four strains of different shell colors and decorative patterns of Meretrix meretrix using microsatellite markers

Genetic variation of four strains of Meretrix meretrix, thin checkered(TC),black spot(BS),dark fringe(DF)and red shell(RS)was studied.Thirty randomly selected individuals from each strain and nine polymorphic microsatellite loci were used for genetic analysis.A total of 105 alleles were identified, the most alleles were 21(WG07)and the least locus were 7(WG11).The distribution of the alleles for the same loci was different in different strains and specific allele types were detected in each strains.All the microsatellites were highly polymorphic,and various genetic variability measures,including observed heterozygosity(0.486 to 0.867), expected heterozygosity(0.110 to 1.000), and polymorphism information content(0.433 to 0.834),Chi-square tests showed that most of the cases in four strains deviated from Hardy-Weinberg equilibrium.Pairwise F_ST ranged from 0.005 to 0.269.Genetic distances among strains ranged from 0.052 0 to 0.098 0.The results of cluster analysis indicated that TC strain had higher genetic difference than other strains,then was BS strain,and the genetic variation between DF and RS strains was relatively lower.