Studies on genetic diversity of Chinese mitten crab Eriocheir sinensis of Yangtze River system based on mitochondrial DNA control region

Abstract

Abstract We obtained mtDNA control region sequences of 102 E. sinensis individuals of 7 populations in Yangtze River system (Adults of E. sinensis in Huangmai, Poyang lake, Pengze, Anqing, Zhenjiang and the Yangtze estuary, juveniles of E. sinensis in Zhenjiang and the Yangtze estuary, abbreviated as HM, PY, PP, AQ, ZC, ZY and CY) and analysed their genetic diversity. The resulted showed that the complete sequences of control region was 515 bp. Total of 65 variation sites including 31 singleton polymorphic sites and 34 parsimony informative polymorphic sites were defined in the 102 individuals sampled of 7 populations, in which 60 haplotypes were detected. The haplotype diversity (Hd) was found to be 0.919±0.023, nucleotide diversity 0.01007±0.00081, the average nucleotide difference (K) 5.106. Genetic differentiation index (Fst) among populations was -0.0098 to 0.0983; genetic distance was 0.0067 to 0.0122; the genetic variation among populations accounts for only 3.3% of total variation. Mismatch distributions suggested that E. sinensis in the Yangtze River system had not experienced a rapid population expansion in the recent past. The results showed that genetic diversity level of E. sinensis in the Yangtze River system was high. The seven populations had not been formed geographic differentiation obviously and apomixes would occur between them.