Mitochondrial DNA restriction fragment length polymorphism analysis of weakfish (Cynoscion regalis) stock structure along the mid-Atlantic coast

To determine the genetic basis of intraspecifc population structure within the weakfish, cynoscion regalis, a total of 376 individuals was collected from four geographic sites along the midAtlantic coast of the United states for two success! ve years. Restriction fragment length polymorphism analysis of weakfish mitochondrial DNA with six restriction endonucleases demonstrated a low level of intraspecific mtDNA variation. The common restriction genotype occurred at a frequency of 0.88 to 0.95 in all samples, and there was no significant heterogeneity found in the frequency of occurrence of the combined rare variants among the samples. Furthermore, the temporal and spatial distribution of the rare variant genotypes is indicative of high levels of gene flow between the samples. These results strongly suggest that weakfish along the mid-Atlantic coast share a common gene pool