4个肉用绵羊品种微卫星标记的多态性与系统发育分析

利用10个微卫星座位对4个肉用绵羊品种进行遗传检测,计算出了各品种的平均杂合度、平均多态信息含量及品种间的遗传距离,并进行了系统发育分析。结果表明:10个微卫星座位上共检测到了107个等位基因,等位基因数在5~13个之间。各基因座位多态信息含量为0.498 5~0.890 4,均表现出了高度多态性。各基因座位杂合度较高,为0.563 0~0.899 5,说明肉用绵羊品种有着较丰富的遗传多样性。4个肉用绵羊品种间的遗传距离相对较远,萨福克羊和陶赛特羊先聚在一起,他们之间的遗传距离最近,为0.345 25,然后与夏洛来羊聚在一起,最后与中国美利奴羊聚在一起,中国美利奴羊与夏洛来羊之间的遗传距离最远,为0.516 39。研究结果对我国肉用绵羊资源的评估、保存和预测杂种优势具有一定的指导意义。

Analysis on phylogenetic relationship and genetic polymorphism using microsatellite DNA markers in four meat sheep breeds

The polymorphism of 10 microsatellites was analysed in four meat sheep breeds. Allele frequencies, effective number of alleles, heterozygosity, polymorphism information content, genetic distance were calculated for all microsatellites in each groups and phylogenetic was analysed as well. A total of 107 alleles were detected from ten microsatellit loci and the number of alleles observed at a locus varied between five and thirteen. All microsatellite loci were highly polymorphic, with the PIC ranging from 0. 498 5 to 0. 890 4. All populations showed high levels of heterozygosity with the lowest value of 0. 563 0 and the highest value of 0. 899 5. The genetic distance were far in four meat sheep. The Suffolk and Dorset sheep were first grouped together with the nearest genetic distance of 0. 345 25, and then together with Charolais, finally together with Chinese Merino. The genetic distance between Chinese Merino and Charolais was the farest of 0. 516 39. The results could be useful as an initial guide in evaluating the level of genetic variation, developing conservation strategies and predicting heterosis.