鲮微卫星引物的鉴定及其适用性检验

利用4种鲤科鱼类的14对微卫星引物对西江流域一批野生鲮进行PCR扩增。将各扩增条带进行克隆测序,发现引物MFW1、MFW2、MFW15、MFW17、Cc7、Cc11、Bgon22扩增出的产物含有微卫星重复序列。进一步对鲮的微卫星位点MFW1、MFW2、Cc7重新设计引物,并将其分别命名为Cm1、Cm2、Cm3,新引物对鲮的扩增特异性增强。采用引物Cm1、Cm2、Cm3、Cc11、MFW15、MFW17、Bgon22对西江流域一批野生鲮进行引物适用性检验。结果表明,除引物MFW15、Cc11无多态性外,其余5对引物(Cm1、Cm2、Cm3、MFW17、Bgon22)在取样群体中扩增图谱带型丰富,随引物不同,各标记在群体中检测到的等位基因数为2到16个。各微卫星座位的期望杂合度(He)及观察杂合度(Ho)范围分别为0~0.9038和0~1,平均分别为0.6881(0.1819SD)和0.7772(0.1931SD)。座位连锁分析显示Cm1与Bgon22之间存在显著性水平连锁关系(P<0.05),其余各座位之间未检测到明显的连锁关系(P>0.05)。研究群体的遗传多样性指数平均为0.6823,多态性水平相对较高。以上结果表明,筛选获得的7个微卫星座位适于对鲮进行遗传多样性分析。

Identification of microsatellite DNA primers in mud carp Cirrhinus molitorella and applicability detection

A group of wild mud carp samples collected from Xijiang River was amplified by PCR using 14 pairs of microsatellite primers isolated from four species of Cyprinidae. The bands were cloned and then sequenced. The products of primer pairs MFW1, MFW2, MFW15, MFW17, Cc7, Cc11 and Bgon22 contained microsatellite sequences. The primers for loci MFW1, MFW2, and Cc7 were redesigned and named as Cm1, Cm2 and Cm3, respectively. The new primers gave more specific amplification in mud carp. The applicability of primer pairs Cm1, Cm2, Cm3, Cc7, MFW15, MFW17 and Bgon22 on wild mud carp samples from Xijiang River was explored, and the genetic diversity of the wild samples was analyzed. The results showed that the detected numbers of alleles within the samples for each primer pair ranged from 2 to 16. Except for the primer pairs MFW15,Cc11, the amplified profiles of the other five (Cm1, Cm2, Cm3, MFW17 and Bgon22) showed high polymorphism.The range of observed heterozygosities and expected heterozygosities were from 0 to 1 (Ho) and 0 to 0.9038(He) with an average of 0.7772(SD=0.1931)and 0.6881(SD=0.1819),respectively.Significant (P<0.05)linkage disequilibrium(LD) exhibited in the sample only between locus Cm1 and Bgon22. The average genetic diversity of the samples was 0.6823, showing the level of polymorphism within the samples was high relatively. This study showed that the seven primer pairs of microsatellite locis screened were suitable for genetic diversity analysis of mud carp.