【摘要】 目的:对藏绵羊β-乳球蛋白(β-Lg)基因序列进行克隆和多态性分析,为藏绵羊资源的利用提供依据。方法:提取基因组DNA,采用PCR方法克隆β-Lg部分基因序列;分别利用PCR-RFLP和高效液相色谱法检测β-Lg基因和蛋白多态性。结果:藏绵羊β-Lg与普通绵羊类似,存在A、B两种遗传变异体,A变异体的基因频率为0.818(n=22);HPLC能很好地分离β-Lg的A、B两种遗传变异体,A的表型频率分别为0.700;β-Lg为杂合型的藏绵羊中,大多数个体乳中的A变异体表达量低于B变异体。结论:藏绵羊β-Lg基因与普通绵羊存在一些差异,有两种变异体,并且其在乳中的相对表达量不同。更多还原

【Abstract】 Objective:The β-lactoglobulin(β-Lg) gene of Tibetan sheep was cloned and its polymorphisms were investigated in order to provide data for its utilization.Method:Genomic DNA was extracted and PCR was employed to clone the partial sequence of β-Lg;Polymorphisms of β-Lg gene and protein were detected by PCR-RFLP and HPLC,respectively.Result:Two genetic variants(A and B) were detected in Tibetan sheep similar to the two common variants in other sheep breeds.The gene frequency of A was 0.818(n=22);The variants were separated perfectly by HPLC.The variant A frequency was 0.700.The expression of variant B is higher than A in most individuals with AB genotype of β-Lg.Conclusion:There existed some differences of β-Lg gene between Tibetan sheep and sheep.Tibetan sheep exhibits two genetic variants of β-Lg with different expression levels in milk.更多还原