绵羊和山羊基于两种标记的遗传分化初步研究

THE PRELIMINARY STUDY OF GENETIC DIFFERENTIATION BASED ON TWO KINDS OF MARKERS IN TWO SHEEP AND GOATS POPULATIONS BY TWO KINDS MARKERS

对湖羊、同羊及长江三角洲白山羊的随机样本分别进行14个结构基因座和7个微卫星标记的遗传检测,比较由2种遗传标记获得的群体基因平均杂合度、多态信息含量及群体有效等位基因数,分别根椐2种类型的基因频率资料,计算3个群体问的标准遗传距离并加以比较。结果表明:由微卫星等位基因频率获得的群体基因平均杂合度、多态信息含量及有效等位基因数显著大于由结构基因座获得的,由结构基因座资料计算的3个群体间标准遗传距离为0.026 8-0.248 7,微卫星标记资料计算的3个群体间标准遗传距离为0.232 1-1.231 3,绵山羊群体间显著大于绵羊间。结构基因座和微卫星标记一致揭示了3群体内的遗传变异程度由大到小依次为同羊、湖羊、长江三角洲白山羊;微卫星标记较结构基因座标记更能表达近缘种间进化趋异水平;可将FCB11、MAF33、AE101、FCB128及FCB304位点作为研究绵山羊近缘种间遗传分化的标志性位点。

The genetic examinations on 14 structural loci and 7 microsatellite markers were carried out using random samples in two sheep populations including Hu sheep (Hu), Tong sheep (Tong) and Yantse River Delta white goats (YRD). Means of heterozygosity (H), polymorphism information content (PIC) and effective number of alleles (Ne) were calculated based on the two types of genetic markers data. The standard genetic distances among the 3 populations based on the two types of gene frequency were calculated and compared. The results showed that among the 3 populations , the H, PIC and Ne based on 7 microsatellite markers were greater than on structural loci. The standard genetic distances based on structural loci among 3 populations were within 0. 026 8 ?0. 248 7, and the standard genetic distances based on microsatellite markers were 0. 232 1-1. 231 3. The study revealed that structural loci and microsatellite markers reflected the genetic variation of the 3 populations consistently: Tong>Hu>YRD. Differentiation on evolution between related species or interpopulations could be expressed more effectively by microsatellite markers than structural markers. Microsatellite loci OarFCBll, MAF33, OarAEl0l, OarFCB128 and OarFCB304 could therefore serve as representative loci for research on genetic differentiation between sheep and goats.