Character based identification system for Elasmobranchs for conservation and forensic applications

The term Elasmobranchs or Chondrichthyans refer to the group of marine organisms include sharks, skates, rays and chimeras. Due to high demand most of the Elasmobranch species depleted drastically in recent years. Being the apex predators in the marine environment most of the Chondrichthyan species are vulnerable with some risk of extinction. Accurate identification of species is prerequisite for conservation and management of these declining resources. In this context, character-based identification methods are of immense use which classify specimen to species using classification rules that compactly characterized species in terms of key diagnostic nucleotides in the selected gene sequences. In the present study, a total of 82 species of elasmobranches distributed in Indian waters is taken as the target group. A total of 20-30 mitochondrial CO1 sequences of each species were downloaded and modified. Using the BLOG2.0 software, species specific diagnostic nucleotides were identified for the selected group of species. Based on identified diagnostic nucleotide sites, species-specific probes with a length range of 23-30 bp were designed. These probes could be useful in detecting species of interest in customized microarrays (DNA chip). The technique is a powerful tool to obtain a significant amount of accurate information quickly and conveniently and could be used for forensic applications and conservation of elasmobranches in Indian waters.