ITS2 for the identification of Calliphoridae (Diptera: Calliphoridae) of forensic importance in Colombia

• Published in: Acta biológica colombiana 2016-09, Vol.21 (3), p.543-553
• Main Authors: Edison R. Lea-Charris, Martha Wolff, Lyda R. Castro
• Format: Article
• Language: eng ; spa
• Subjects: códigos de barra genéticos; enzimas de restricción; genoma nuclear; intervalo post-mortem
• ISSN: 0120-548X; 1900-1649
• DOI: 10.15446/abc.v21n3.55085

Forensic entomology is a discipline that uses insects to obtain useful information for the determination of the postmortem interval (PMI). Flies of the family Calliphoridae are extensively used for this purpose, however, the identification of these flies can be difficult when the individual is not an adult or when it is incomplete. In the present work, we tested the utility of the ITS2 region of the nuclear genome for the identification of Calliphoridae species in Colombia using three approaches: comparing genetic distances using the barcoding methodology, with a phylogenetic reconstruction, and with PCR-RFLPs. We sequenced 520 bp in 44 individuals belonging to 16 species of califorids. Intraspecific and interspecific distance values were calculated using the K2P model. The intraspecific distance values ranged between 0 and 0.252 %, while the interspecific distance values ranged between 3.6 and 18.9 %, indicating that this gene can be used as a genetic barcode for the identification of species of the Calliphoridae family. Both the Neighbour-Joining and Bayesian analyses recovered 90 % of the genera as monophyletic, with pp values between 0.89 and 1. Blepharicnema splendens was always recovered within the Lucilia genera. Based on the obtained sequences we used the NEBCutter application to identify four restriction enzymes that cut in a differential way and generated useful patterns for the identification of the species. The enzymes were successfully tested and confirmed the utility of this technique as a fast way to identify species of Calliphoridae in Colombia.