Survey of the Genetic Diversity of Forensically Important Chrysomya (Diptera: Calliphoridae) from Egypt

• Published in: Journal of medical entomology 2015-05, Vol.52 (3), p.320-328
• Main Authors: Salem, Abeer M., Adham, Fatma K., Picard, Christine J.
• Format: Article
• Language: English
• Subjects: Animals; Blow fly; Cadaver; Calliphoridae; Chrysomya; Chrysomya albiceps; Chrysomya megacephala; COI; crime; cytochrome-c oxidase; Diptera; Diptera - classification; Diptera - genetics; Diptera - growth & development; DIRECT INJURY, MYIASIS, FORENSICS; DNA; DNA barcoding; Egypt; Electron Transport Complex IV - genetics; Electron Transport Complex IV - metabolism; forensic entomology; Forensic Pathology; genes; Genetic Variation; Haplotypes; Humans; immatures; insect larvae; Insect Proteins - genetics; Insect Proteins - metabolism; Larva - classification; Larva - genetics; Larva - growth & development; Minyas; Mitochondrial Proteins - genetics; Mitochondrial Proteins - metabolism; Molecular Sequence Data; phylogenetic analysis; Phylogeny; Polymerase Chain Reaction; Postmortem Changes; Sequence Analysis, DNA; species identification; surveys; topology
• ISSN: 0022-2585; 1938-2928
• DOI: 10.1093/jme/tjv013

Minimum postmortem interval estimations of a corpse using blow fly larvae in medicolegal investigations require correct identification and the application of appropriate developmental data of the identified fly species. Species identification of forensically relevant blow flies could be very difficult and time consuming when specimens are damaged or in the event of morphologically indistinguishable immature stages, which are most common at crime scenes. In response to this, an alternative, accurate determination of species may depend on sequencing and molecular techniques for identification. Chrysomyinae specimens (n = 158) belonging to three forensically important species [Chrysomya albiceps (Wiedemann), Chrysomya megacephala (F.), and Chrysomya marginalis (Wiedemann)] (Diptera: Calliphoridae) were collected from four locations in Egypt (Giza, Dayrout, Minya, and North Sinai) and sequenced across the mitochondrial cytochrome oxidase subunit I (COI) gene. Phylogenetic analyses using neighbor—joining, maximum likelihood and maximum parsimony methods resulted in the same topological structure and confirmed DNA based identification of all specimens. Interspecific divergence between pairs of species was 5.3% (C. marginalis—C. megacephala), 7% (C. albiceps—C. megacephala), and 8% (C. albiceps—C. marginalis). These divergences are sufficient to confirm the utility of cytochrome oxidase subunit I gene in the molecular identification of these flies in Egypt. Importantly, the maximum intraspecific divergence among individuals within a species was