Genetic Diversity And Genetic Differentiation Of Elaphe Schrenckii And Elaphe Anomala Based On Mitochondrial DNA

Elaphe schrenckii and Elaphe anomala belong to Elaphe,Colubridae,Serpentes,Squamata,Diapsida,Reptilia.E.schrenckii is mainly distributed in Heilongjiang Province and Jilin Province in China.It is also distributed in the eastern mountains of Liaoning Province and is the southernmost limit.It is distributed in Siberia of Russia and Korea abroad;E.anomala is mainly distributed in the north of the Yangtze River in China,and is also found in the Yangtze River basin.Inner Mongolia is the northernmost limit of its distribution,while abroad is mainly distributed in Korea.They overlap and distribute in Liaoning Province of China and Korea.At present,studies on population genetic diversity and genetic differentiation of E.schrenckii and E.anomala has not been fully carried out.A total of 55 samples from 16 populations of E.schrenckii and E.anomala in northeastern China were collected,and the genetic diversity and population genetic structure of E.schrenckii and E.anomala were studied by sequencing the Mitochondrial DNA cytochrome b and 12S ribosomal RNA two-gene sequence.The haplotype diversity?h?and nucleotide diversity???of the whole population of E.schrenckii were 0.538 and 0.00042,respectively.The whole population of E.anomala also showed relatively high haplotype diversity and relatively low nucleotide diversity,with 0.581 of haplotype diversity?h?and0.00051 of nucleotide diversity???,slightly higher than E.schrenckii.5 variance sites were found in 21 two-gene sequences of E.schrenckii,and 5 haplotypes were defined with 3unique haplotypes.There were 11 variance sites in 34 two-gene sequences of E.anomala,and10 haplotypes were defined with 8 unique haplotypes.There were shared haplotypes between both snakes in their populations.The base-to-base transition and transversion ratio of two snakes were 214.567 and 1.148,respectively;The genetic distances between populations were0⁰.00099,0⁰.00119,and the average genetic distances were 0.00041 and 0.00055,respectively.Phylogenetic tree based on two-gene sequences divided them into two branches.In addition,the genetic differentiation index(F_ST)and gene flow?Nm?indicated that there were different degrees of genetic differentiation among populations.The lower genetic distance value?GD?indicated that the genetic variation among populations is small.The molecular variance analysis?AMOVA?showed that overall population divergent variation of E.schrenckii and E.anomala were both occurred within populations.The neutral test analysis and mismatch distribution analysis suggested that the size of the population of the E.schrenckii and E.anomala was relatively stable,no large-scale expansion was detected in the near future.During the collection of E.schrenckii and E.anomala,it was found that the number of wild populations of the two snakes had shown a downward trend.The habitat structure of the two snakes is single and some habitats are seriously damaged by environmental pollution,climate change and human activities.It has become an urgent problem to study and analyze the genetic diversity of the existing populations of E.schrenckii and E.anomala,and to carry out effective protection accordingly.