Genetic variability of swimming crab based on PCR-RFLP analysis of mitochondrial DNA D-loop region

摘要

Restriction fragment length polymorphism analysis was performed on Polymerase Chain Reaction amplified DNA fragments containing the D-loop region of swimming crab Portunus trituberculatus mitochondrial DNA (mtDNA). A total of 234 individuals consisting of eight populations around Japan were surveyed with four restriction endonucleases (Dra I, Hinc II, Mbo I and PshB I), yielding a total of 28 composite haplotypes. Within population of haplotypic diversity (h) and nucleotide diversity (pi) were ranging from 0.403 (Miyagi) to 0.903 (Okayama) and from 0.0020 (Miyagi) to 0.0101 (Shizuoka), respectively. The Miyagi population was highly distinct from all other populatons. The homogeneity test by a chi-square randomization analysis demonstrated significant differences between Miyagi population and all the other six populations examined, and between Kumamoto and other two populations, Sizuoka and Okayama. The dendrogram clustering based on nucleotide divergence between populations, showed no clusteringgroup of georaphical cline. Significance of hapolotype diversity (h) and nucleotide diversity (pi) values obtained of swimming crab populations in the present study were discussed together with the data in mud crabs, differences in the genetic diversitybetween the mtDNA whole region and D-loop region, and the effects of stocking of artificially propagated larvae to the genetic composition of local populations in the swimming crab.