关键词: MHC, DRB3.2基因, 核苷酸序列, 同源性分析

Abstract: Objective To study the homology of MHC-DRB3.2 gene in human beings and some laboratory animals.Methods Cattle genomic DNA was used as the template to amplify DRB3.2 gene fragment by PCR and the products of PCR were sequenced.The DRB3.2 gene fragment of other laboratory animals,including human beings,macaque,sheep,goat and swine were down loaded from GenBank,and base compositions,homology and molecular evolution trees were analysis by DNAMAN software.Results DRB3.2 gene fragment in all those species mentioned above were 267 base pairs and the gene hasn't any deletion or insertion.There is no significant difference in the base contents of A,T,G,C and G+C among those animal species.As for certain special animal,the content of G was the highest and T was the lowest,the content of G+C was obviously higher than that of A+T.The homology between human beings and macaque,sheep,goat,cattle and swine were 91.8%,82.8%,82.4%,81.3% and 81.6%,respectively.Conclusion The nucleotide sequence homology of DRB3.2 gene shares a high sequence identity in different species;macaque plays a very important role in studies of human diseases,and it could not be replaced by other laboratory animals.DRB3.2 gene is an ideal genetic marker for organic evolution and phylogeny analysis.

Key words: MHC, DRB3.2 gene, Nucleotide sequences, Homology analysis