Haplotype Diversity,Genetic Differentiation and Population Expansion of Haemaphysalis longicornis Isolated from Different Districts
[Objective]This study was aimed to explore the haplotype diversity(Hd),genetic differentiation and population expansion of Haemaphysalis longicornis(H.longicornis)collected from Liuyang and Xinyang districts,so as to provide data support and theoretical basis for subsequent research on the population genetic structure of H.longicornis.[Method]A total of 30 H.longicornis were used as samples in this study.The sequences of cox1 and nad5 genes were amplified by PCR,and were then sequenced.The haplotype diversity of H.longicornis from two districts were analyzed using Clustal X,Dnasp 5.0 and Network 4.6 software.The genetic differentiation and population expansion of H.longicornis from two districts were analyzed by Dnasp 5.0 and Arlequin version 3.0 softwares.[Result]There were 4 mutational sites and 5 haplotypes(A1-A5,Hd=0.3609)in the sequence of cox1 gene(776 bp),and the gene differentiation coefficient(Gst),fixation index(Fst)and gene flow(Nm)of cox1 gene were-0.0154,-0.019 and-26.82,respectively.There were 33 mutational sites and 17 haplotypes(B1-B17,Hd=0.9402)in the sequence of nad5 gene(519 bp),the Gst,Fst and Nm of nad5 gene were 0.0316,0.0503 and 9.44,respectively.There were 37 mutational sites and 20 haplotypes(C1-C20,Hd=0.9563)in the sequence of cox1+nad5 gene(1 295 bp),the Gst,Fst and Nm of the combined gene were 0.0184,0.0451 and 10.59,respectively.All results indicated that H.longicornis from Liuyang and Xinyang districts didn't appear genetic differentiation.In the population expansion analysis of H.longicornis using cox1,nad5 and cox1+nad5 gene sequences,it was found that H.longicornis from Liuyang and Xinyang districts experienced multiple population expansions.[Conclusion]H.longicornis from Liuyang and Xinyang districts had low level of genetic variation and haplotype diversity,but there was higher frequency of gene exchange among individuals,no obvious genetic differentiation was found among H.longicornis individuals,and there were population expansions for H.longicornis from Liuyang and Xinyang districts.
万方数据
维普
