Genetic Diversity Of Y Chromosome Specific Gene(Zfy1,Zfy2) In Chinese House Mouse

House mouse(Mus musculus),belonging to Rodentia,Muridae,Mus,is a kind of human commensals,which widely distributes all over the world.Both the wild populations of house mice and various laboratory strains have been widely used in biological or biomedical studies.Due to its strict paternal inheritance,the evolutionary history of Y chromosome has always been one of the important research topics in speciation field.ZFY genes,important male-specific genes on Y chromosome,play important roles in spermatogenesis and sperm development.The sequence characteristics and population genetic structure of ZFY genes are of great value for us to understand the evolutionary mechanisms of male-specific genes on Y chromosome.In this thesis,we amplified,sequenced the Zfy1 and Zfy2 genes,and analyzed the genetic diversity and population structure of all obtained sequences.Totally,we got 251 Zfy1 fragments(561 bp in length)from 21 localities and 251 Zfy2 segments(583 bp in length)from 21 localities.The results showed that: 1)the average base compositions of Zfy1/Zfy2 were slightly different(A: 25.1%/28.2%,T: 39.6%/36.1%,G: 20.7%/20.6%,C: 14.6%/15.1%);a total of 25/24 variation sites(V)and 29/28 haplotypes(H)were defined in all 251 fragments of two genes.2)the genetic diversity of Zfy1/Zfy2 in different geographic populations were very different(haplotype diversity,Hd = 0.874-0.280 / 1.000-0.182;nucleotide diversity,? = 0.01007-0.00072 / 0.00287-0.00058),but the average genetic diversity of two genes were low(Hd = 0.465/0.627;? = 0.00228/0.00182);3)for both genes,there was no significant nucleotides difference between different populations(nucleotide difference value,Dxy= 0.00000-0.01090 / 0.00000-0.00558)and the genetic distance between different populations were small(0.00000-0.00872 / 0.00000-0.00561);most of the sequence variations(92.83% / 92.81%)existed within population(AMOVA analysis);4)phylogenetic trees including all haplotypes of Zfy1/Zfy2 sequences showed neither clear specific clade nor obvious geographical clusters of haplotypes.All above results indicated that the Zfy1/Zfy2 genes of Chinese house mice were conservative in the evolutionary process,and the genetic differentiation among different geographical populations was small.Previous investigations based on mitochondrial gene markers showed that Chinese house mice including two subspecies(M.m.musculus and M.m.castaneus)and the Yangtze River was the distribution boundary of two subspecies.The inconsistent results from mitochondrial gene markers and male specific genes indicated that maternal divergence and paternal divergence would be asynchronous during species evolution.Our study provided important data for exploring the evolutionary mechanism of paternal genetic markers in Chinese house mice.