小尾寒羊五个微卫星基因座遗传多态性研究

小尾寒羊是我国优良的地方绵羊品种，具有极高的繁殖力，平均每胎产羔2．6只。利用与绵羊高繁殖力主效基因Fec^B和FecX^1连锁的5个微卫星标记（OarAE101,BM1329,BMS2508,TGLA54t TGLA68)对244小尾寒羊母羊进行了遗传检测。用非变性（中性）聚丙烯酰胺凝胶电泳检测同卫星的PCR扩增产物，计算了5个同卫星基因座的等位基因频率，多态信息含量，基因纯合度和杂合度。在小尾寒羊中检测到BM1329有6个等位基因，片段大小为160－180bp,164bp等位基因频率最高（0．6320）；检测到OarAE101有9个等位基因，片段大小为97－135bp,97bp等位基因频率最高（0．7930）；检测到TGLA54有5个等位基因，片段大小为116－136bp,134bp等位基因频率最高（0．8500）；检测到TGLA68有2个等位基因，片段大小为98－100bp，2个等位基因频率相近，检测到BMS2508有6个等位基因，片段大小为93－115bp,99bp等位基因频率最高（0．4795）。BM1329，OarAE101,TGLA54,TGLA68,BMS2508的多态信息含量／基因纯合度／杂合度分别为0．4481／0．4840．0．5160，0．3516／0．6375／0．3625，0．2528／0．7326／0．2674，0．3733／0．5034／0．4966，0．5809／0．3581／0．6419。可见BMS2508的遗传变异最大，TGLA54的遗传变异最小。这些结果可为小尾寒羊种质特性研究提供分子基础数据。

Genetic Polymorphisms of Five Microsatellite Loci in Small Tail Han Sheep

Small Tail Han sheep is an excellent local sheep breed in China. Small Tail Han sheep had significant characteristics of high prolificacy. The lambing percentage averaged 260 percent in Small Tail Han sheep. The polymorphisms of 5 microsatellite loci OarAE 101, BM 1329, BMS 2508, TGLA 54 and TGLA 68 which were closely linked to the fecundity genes Fec B and FecX I in sheep were detected in 244 ewes of Small Tail Han sheep. The PCR amplified products of microsatellites were detected by non denatured (natural) polyacry lamide gel electrophoresis. Allele frequency, polymorphism information content, gene homogeneity and heterozygosity for 5 microsatellite loci were calculated. The number of alleles for BM 1329, OarAE 101, TGLA 54, TGLA 68 and BMS 2508 were 6, 9, 5, 2 and 6 in Small Tail Han sheep, respectively. The range of allele sizes for BM 1329, OarAE 101, TGLA 54, TGLA 68 and BMS 2508 were 160bp to 180bp, 97bp to 135bp, 116bp to 136bp, 98bp to 100bp, and 93bp to 115bp, respectively. The alleles of the greatest frequency for BM 1329, OarAE 101, TGLA 54 and BMS 2508 were 164bp,97bp,134bp and 99bp, respectively. Polymorphism information content/gene homogeneity/heterozygosity for BM 1329, OarAE 101, TGLA 54, TGLA 68 and BMS 2508 were 0.4481/0.4840/0.5160,0.3516/0.6375/0.3625,0.2528/0.7326/0.2674, 0.3733/ 0.5034 /0.4966 and 0.5809/0.3581/0.6419 in Small Tail Han sheep,respectively. The results revealed the greatest genetic variation in BMS2508 and the lowest in TGLA54.These results could provide, basic molecular data for the research on the germplasm characteristics of Small Tail Han sheep.