Polymorphic Analysis Based On MHC-DQA1 And MHC-DQB1 Gene In Different-altitude Area Of Rhesus Macaque

Rhesus macaque(Macaca mulatta)belongs to national second-class protected animals and important primate model animals.Accordingly,the research for its wild population genetic information does not only benefit to comprehensive analyze the history and survival of population evolution,but also to provide some guidance for future scientific biology research to provide patterns of animals with more definite genetic background information,on the basis of protection.Rhesus macaque major histocompatibility complex(MHC),also known as Mamu,polymorphism level has important implications on the immune function ability to adapt to the environment.In this study,it counts the distribution of Mamu-DQA1 and DQB1 gene alleles from five wild populations via clone and DNA-seq;then preliminary grasps the genetic polymorphism of MHC gene in each region.This study provides the basis for the study for MHC gene evolution mechanism of the Macaca mulatta in China.The primary results of this study are as follows:1)In this study,it obtains MHC-DQA1 gene 417 effective sequences and 42 alleles,Mamu-DQB1 gene 374 effective sequences and 34 alleles by separately cloning and sequencing.Among them,31 Mamu-DQA1 alleles and 18 Mamu-DQB1 alleles were found for the first time.2)There are 156 nucleotides mutation sites and 47 amino acid mutations from 42 Mamu-DQA1 alleles,accounting for 62.65%and 58.00%of the total analysis sites respectively.While Mamu-DQB1 alleles have 91 nucleotides mutation sites and 47 amino acid mutations,accounting for 33.70%and 53.41%respectively.The results indicate that mutation happened in multiple sites of DQA1 and DQB1 genes.In addition,the presence of multiple alleles and the gene recombination were both found in Mamu-DQA1 and DQB1 genes exon2,and the alleles frequencies have big difference in the five populations.Based on the research hereinbefore,Mamu-DQA1 and DQB1 genes are highly polymorphic.3)Our study respectively found nine Mamu-DQA1/DQB1 identical shared alleles among Mamu,Mafa and Mane.At the same time,the phylogenetic trees show that three species alleses staggered distribution and aggregate into branches through lineages.In addition,by selection pressure analysis,the synonymous and nonsynonymous substitution values were both similar.Thus,it verify that,with the evolution of Mamu,balance selection is one of the main mechanisms in maintainingits polymorphism.4)The genetic differentiation analyze shows that gene flow values of Mamu-DQA1 and DQB1 genes were greater than 1 in each pair,and all Macaca mulattas populations have no reproductive isolation.While there are some differences in the degree of differentiation among the five populations,in which the population in Tibet are the most significant.Analysis of the genetic variation in five regions' populations showed that intraspecific variation dominated the two genes.5)The results of this study show that there are differences in allele types,detection frequency and genetic differentiation of Mamu-DQAl and DQB1 genes exon2.It may be due to each environment differencin elevation,pathogens,microbes and so on,which make every site under differents election pressure.