A novel mini-DNA barcoding assay to identify processed fins from internationally protected shark species

PLoS One. 2015 Feb 3;10(2):e0114844. doi: 10.1371/journal.pone.0114844. eCollection 2015.

Abstract

There is a growing need to identify shark products in trade, in part due to the recent listing of five commercially important species on the Appendices of the Convention on International Trade in Endangered Species (CITES; porbeagle, Lamna nasus, oceanic whitetip, Carcharhinus longimanus scalloped hammerhead, Sphyrna lewini, smooth hammerhead, S. zygaena and great hammerhead S. mokarran) in addition to three species listed in the early part of this century (whale, Rhincodon typus, basking, Cetorhinus maximus, and white, Carcharodon carcharias). Shark fins are traded internationally to supply the Asian dried seafood market, in which they are used to make the luxury dish shark fin soup. Shark fins usually enter international trade with their skin still intact and can be identified using morphological characters or standard DNA-barcoding approaches. Once they reach Asia and are traded in this region the skin is removed and they are treated with chemicals that eliminate many key diagnostic characters and degrade their DNA ("processed fins"). Here, we present a validated mini-barcode assay based on partial sequences of the cytochrome oxidase I gene that can reliably identify the processed fins of seven of the eight CITES listed shark species. We also demonstrate that the assay can even frequently identify the species or genus of origin of shark fin soup (31 out of 50 samples).

MeSH terms

  • Animal Fins*
  • Animals
  • Conservation of Natural Resources*
  • DNA Barcoding, Taxonomic / methods*
  • Endangered Species*
  • Food Handling*
  • Internationality
  • Sequence Analysis, DNA
  • Sharks / anatomy & histology
  • Sharks / classification*
  • Sharks / genetics*

Grants and funding

This research was funded by The Pew Charitable Trusts (Global Shark Campaign and Ocean Science Division), the Pew Fellowship Program and the Roe Foundation (to DDC). Genetic data were collected in the Field Museum's Pritzker Laboratory for Molecular Systematics and Evolution operated with support from the Pritzker Foundation. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.