中文摘要：

目的：实验通过MCH-DRB3基因来探讨卡拉库尔羊的遗传多态性,为绵羊遗传资源的合理利用及保护提供理论基础和科学依据。方法：采用PCR-Clone测序方法首次对卡拉库尔羊的MHC-DRB3基因的第二外显子进行分子遗传多态性检测与分析。结果：总共检测出35种单倍型,总的单倍型多样度（Hd）为0.958,核苷酸多样性（Pi）为0.05786,平均核苷酸差异数（k）为16.49062,简约信息多态位点数为54。卡拉库尔羊MHC-DRB3基因的氨基酸序列的氨基酸组成进行分析可知含量最多的氨基酸是精氨酸（Arg）,平均含量为12.9%,含量最低的氨基酸是蛋氨酸（Met）,平均含量为0.018%。结论：从以上参数可以看出卡拉库尔羊具有很高的遗传多样性。

英文摘要：

Objective：MHC is a chromosomal region consisting of a group of closely linked loci which are highly polymorphic,and plays a central role in the immune system.This study was designed to investigate the polymorphism of MHC-DRB3 in domestic sheep breed named kalakuer sheep and by analyzing its polymorphism to provide theoretical and scientific evidence for local sheep management and usage.Method：MHC-DRB3 gene exon 2 in Kalakuer sheep was analyzed by polymerase chain reaction with clone sequencing method（PCR-Clone sequencing）.Result：MHC-DRB3 gene is highly diverted in kalakuer sheep,35 haplotypes were detected.Haplotype（gene） diversity（Hd）is 0.958,Nucleotide diversity（per site） Pi 0.05786,Average number of nucleotide differences（k）16.49062,among all haplotypes,total of 61 variable sites were found,among them Parsimony informative sites were 54.It is known from the analysis of amino acid that among all amino acids the most abundant amino acids are arginine（Arg）,the average content of 12.9%,the lowest content of amino acids is methionine（Met）,the average content of 0.018%.Conclusion：All these mentioned above indicates that Kalakuer sheep has very diversed polymorphism.