Microsatellite DNA Variation in Sandbar Sharks (Carcharhinus plumbeus) from the Gulf of Mexico and Mid-Atlantic Bight

Abstract

Three polymorphic DNA microsatellite loci were developed in the sandbar shark (Carcharhinus plumbeus) and used to test the hypothesis that sharks from the midAtlantic Bight and western Gulf of Mexico comprise a single genetic stock. No significant differences in microsatellite allele frequencies were detected, a finding consistent with the null hypothesis. Polymorphic microsatellite loci appear to be scarce in sandbar sharks relative to other fish species. The three loci examined in this study had relatively low levels of heterozygosity, most likely attributable to the small number of dinucleotide repeat units per locus. T HE sandbar shark (Carcharhinus plumbeus) is