Use of Molecular Tools on Surveys of Genetic Variation and Population Structure in Three Species of Sharks

Download or read book Use of Molecular Tools on Surveys of Genetic Variation and Population Structure in Three Species of Sharks written by Andrey Leonardo F. Castro and published by . This book was released on 2009 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: ABSTRACT: Molecular tools, such as sequencing of the mitochondrial DNA Control Region (CR) and genotyping of highly variable nuclear microsatellites were applied to survey the genetic diversity, population structure and phylogeography of three shark species: the whale shark, Rhincodon typus; the bull shark, Carcharhinus leucas; and the nurse shark, Ginglymostoma cirratum. The highly migratory and pelagic whale shark exhibited the largest length variation yet reported for an elasmobranch CR (1143-1332 bp), and high haplotype (h = 0.974 +/- 0.008) and nucleotide diversities (pi=0.011 +/- 0.006). No geographical clustering of lineages was observed and the most common haplotype was distributed globally. The haplotype frequency, however, differed between the Atlantic and Indo-Pacific populations (AMOVA, phiST = 0.107, rho 0.001). For the bull shark, both mtDNA CR and five microsatellite loci were surveyed for animals from the Gulf of Mexico, the East coast of Florida and the Brazilian coast. Strong genetic structure was observed between the Brazilian and all northern populations for the CR (phiST0.8, rho