Niranjan Saket K, Deb Sitangsu M, Kumar Subodh, Mitra Abhijit, Sharma Arjava, Sakaram Durgam, Naskar Soumen, Sharma Deepak, Sharma Sita R
Animal Genetics Division, Indian Veterinary Research Institute, Izatnagar, UP 243122, India.
Vet Immunol Immunopathol. 2010 Dec 1;138(3):206-12. doi: 10.1016/j.vetimm.2010.07.014. Epub 2010 Jul 30.
The genetic diversity of MHC class II DQ genes was investigated in riverine buffalo (Bubalus bubalis) by PCR-RFLP and sequencing. Highly variable regions (exons 2-3) of DQ genes were amplified from 152 buffaloes and genotyped by PCR-RFLP. Alleles identified by differential restriction patterns were sequenced for the characterization. PCR-RFLP was a rapid method to discriminate between DQA1 and duplicated DQA2 genes in buffalo, however, the method appeared to be inadequate for determining the more complicated DQB genotypes. A total of 7 and 10 alleles were identified for DQA and DQB loci, respectively. Nucleotide as well as amino acid variations among DQ alleles particularly at peptide binding regions were high. Such variations were as expected higher in DQB than DQA alleles. The phylogenetic analysis for both genes revealed the grouping of alleles into two major sub-groups with higher genetic divergence. High divergence among DQ allelic families and the isolation of two diverse DQA and DQB sequences from individual samples indicated duplication of DQ loci was similar in buffalo to other ruminants.
通过聚合酶链反应-限制性片段长度多态性分析（PCR-RFLP）和测序技术，对河流型水牛（Bubalus bubalis）主要组织相容性复合体II类DQ基因的遗传多样性进行了研究。从152头水牛中扩增出DQ基因的高变区（外显子2-3），并通过PCR-RFLP进行基因分型。对通过不同限制性模式鉴定出的等位基因进行测序以进行特征描述。PCR-RFLP是一种快速区分水牛DQA1基因和重复的DQA2基因的方法，然而，该方法似乎不足以确定更为复杂的DQB基因型。分别为DQA和DQB基因座鉴定出7个和10个等位基因。DQ等位基因之间的核苷酸以及氨基酸变异，尤其是在肽结合区域，变异程度很高。正如预期的那样，DQB等位基因的变异高于DQA等位基因。对这两个基因的系统发育分析显示，等位基因被分为两个主要亚组，遗传差异较大。DQ等位基因家族之间的高度差异以及从单个样本中分离出两种不同的DQA和DQB序列表明，水牛中DQ基因座的重复与其他反刍动物相似。
