2种兼用型牛BoLA-DQB·exon2基因的多态性与乳房炎的相关性

Analysis of polymorphisms of BoLA-DQB·exon2 and the association between the gene and mastitis in two dual-purpose cattle

【目的】探讨牛主要组织相容性复合物基因第二外显子(BoLA-DQB.exon2)的多态性与乳房炎发生的关系。【方法】采用PCR-SSCP分子标记技术,检测84头中国西门塔尔牛和130头三河牛BoLA-DQB.exon2基因的多态性,并用体细胞记数法检测乳房炎的感染情况,应用GLM模型分析BoLA-DQB.exon2的多态性与奶牛乳房炎的相关性。【结果】BolA-DQB.exon2的基因型及等位基因频率在感染乳房炎牛和健康牛之间分布差异显著(P<0.05)。在感染乳房炎的中国西门塔尔牛中,EE基因型、E等位基因频率最高,在健康的中国西门塔尔牛中,AA基因型、A等位基因频率最高;在感染乳房炎的三河牛中,DD基因型、D等位基因频率最高,而在健康的三河牛中,EE基因型、E等位基因频率最高。【结论】BolA-DQB.exon2多态性与牛乳房炎的发生存在关联,但这种关联在两个品种中的表现不同。

【Objective】 This study is to investigate the association between Bovine Lymphocyte Antigen-DQB gene polymorphism and mastitis.【Method】 The genotypes of DQB gene polymorphism（DQB at exon 2） of 84 Chinese Simmental cattle（13 infected with mastitis,71 healthy ones） and 130 Sanhe cattle（37 infected with mastitis,93 healthy ones） were determined by polymerase chain reaction-single strand conformation polymorphism analysis to compare if there were any differences between mastitis cattle and healthy ones of the same species as to the frequency distribution of genotypes and alleles.【Result】 The frequencies of DQB·exon2 genotypes and alleles were different between mastitis cattle and healthy ones（P〈0.05）.The frequencies of EE genotypes and E alleles were the highest in Chinese Simmental infected with mastitis,while the AA genotypes and A alleles were the highest in healthy Chinese Simmental.In addition,the frequencies of DD genotypes and D alleles were the highest in Sanhe cattle with mastitis,while the EE genotypes and E alleles were the highest in the healthy Sanhe cattle.【Conclusion】 The polymorphism of BolA-DQB·exon2 is associated with mastitis,but the association is different in the 2 species mentioned above.