Microsatellite DNA Profiling in the Blue Shark Prionace glauca : Development and Potential Application for Population Studies.

he world-wide increase in shark fisheries is thought to be resulting in declining population numbers of many species. The blue shark ( Prionace glauca ), possibly the most abundant of the larger pelagic sharks, is no exception. In addition to a directed fishery, large numbers of blue sharks make up the bycatch in the tuna and swordfish fishery. Increased fishing pressure and inadequate management strategies have prompted concerns about the sustainable health of blue shark populations. The main reason for inadequate management measures is the paucity of information on population genetic structure and life history strategy for this species. Traditional methods used to gather this type of information such as allozyme electrophoresis and RFLP analysis of mitochondrial DNA have proved to be only of limited use due to the apparent low rate of molecular evolution in this and other shark species. Recently, microsatellite DNA profiling techniques have been proposed as an alternative source of highly informative molecular makers. This new class of markers has not yet been fully exploited for shark population studies. Here we report on the development of blue shark microsatellite markers from an enriched library. Their potential for blue shark population genetic studies with examples is also discussed.