Structure Analysis of Mitochondrial DNA Control Region Sequences and its Applications for the Study of Population Genetic Diversity of Acanthogobius ommaturus

Abstract

Acanthogobius ommaturus, which belongs to the family Gobiidae, is a euryhaline, demersal fish widely distributed in coastal areas, harbors, and estuaries of China, the Korean Peninsula, and Japan. A genetic analysis based on identification of the structure of mitochondrial DNA control region was carried out in the present study. As a result, the conservative structure, including termination sequence region, central conservative region CSB-E and CSB-D, as well as conservative sequence region CSB-1, CSB-2, and CSB-3, was determined. A total of 32 polymorphic sites were identified and 33 haplotypes were defined, of which only 9 were shared haplotypes. A high level of haplotype diversity (h = 0.923 ± 0.018) and low nucleotide diversity (π = 0.003 ± 0.002) were detected. In general, the genetic differentiation among ten populations was at a medium level. There was a distinct single peak in the nucleotide mismatch distribution, which confirms that A. ommaturus populations have experienced recent expansion. In this study, the control region structure of A. ommaturus was similar to that of most marine fishes; however, the tandem repeat sequence and the CSB-F sequence were not detected. In addition, most of the genetic variation in the control region occurred in the high-variation region.