Study of genetic variability of the Blue Shark Prionace glauca (Linnaeus, 1758)

The Blue Shark (Prionace glauca, Linnaeus, 1758) is one of the most abundant sharks in the epipelagic zone (0-200 m) and its population is distributed in oceans of tropical and temperate climate. Currently, these animals have been considered predatory fishing target and are classified as low-risk or near-endangered, according to the Red List of International Union for the Conservation Nature (IUCN). Aiming study conservation aspects of the specie, the purpose of this study is verifying the occurrence of population under-structuring in Prionace glauca. This study was started by analysis of control region of mitochondrial DNA sequences of 254 Prionace glauca individuals, obtained from the Genbank database, as well as new sequences obtained from laboratory. The second step, sequencing of another 16 individuals of the same specie was made and added to the database for a new comparison. From the current results, we can verify that there are haplotypic difference in individuals of the same species, indicating that they belong to distinct lineages. The difference observed between haplotypes indicates that there is a great migratory potential of this specie. This study will be extended with a larger number of samples and the inclusion of nuclear markers, aiming at a better understanding of the processes that act at the population level.