Compatative Gonomics Identification Of Wild Boars In China And Genetic Diversity Analysis

Wild boar is an important resource of mammals,has important economic value.The purpose of this study is to fully reveal the genetic diversity of wild boars in China by using high-throughput deep sequencing and to evaluate the molecular characteristics of the main excellent traits.The results would help to fill the gap of unclear wild boar population in our country and provide the basis of population genetics and theoretical guidance.Conclusions presented in this thesis can be summarized as follows:A total of 226 SNP(0.014 SNPs/bp)were identified in 38 wild boars in whole genome sequence of mitochondria DNA,including 33 SNPs(0.028 SNPs/bp)in D-loop region.Based on different geographical populations,the 38 wild boars could be divided into nine groups,including Sumatra,Europe,Japan,Shanxi,Sichuan,Hunan,Jiangxi,Zhejiang and Inner Mongolia.For the analysis of GC content in whole genome sequence of mitochondria DNA in each group,the GC contents were not much changed,34.7%for A,26.2%for C,13.3%for G and 25.8%for T,respectively.For the D-loop region,compared to whole genome sequence of mitochondria DNA,A content reduced 1%and G content raised 1%.The analysis of phylogenetic tree and PCA show that there was significantly divided into two groups between European group and Asian group.It indicates that the two groups were independent evolution.On the other hand,seven different geographical populations in China could be divided into three subspecies(Mongolian,Sichuan-Shanxi,and South China wild boar).The results of nucleotide diversity analysis showed that the genetic distance were smaller(average π is 0.0022;range from 0.00024 to 0.0037)amongst the wild boars in China.However,there was large nucleotide diversity(average is 0.0049;range from 0.0044 to 0.0052)between European group and Chinese group.Sumatra and Japan groups were average 0.0025 nucleotide diversity compared to Chinese group.It indicates that comparing to Sumatra and Japanese wild boars,the European ones have large nucleotide diversity with Chinese wild boars.A total of 16306350 SNPs were found in 48 wild boars distributed in 16 geographic populations in China,including 20490 synonymous SNPs,involving 4020 genes,nonsynonymous SNP 10759,involving 2794 genes.By using NJ method analysis of wild boar based on IBS distance,the wild boars in China is divided into five populations,the northern population represented by Jilin and Inner Mongolia,the Sichuan-Shanxi population represented by Sichuan,Yunnan and Shanxi,the southern population represented by Zhejiang,Hubei,Fujian Province;mini-pig population represented by Wuzhishan,Luchuan,Bama Xiang pig and Vietnam wild boar,and Tibetan population represented by Tibet pig.Samples were analyzed using principal components(PCA)and STRUCTURE and the results were consistent with the NJ tree classificatio.