Identification Blow Fly Species in Korea by Mitochondrial DNA 'Barcodes' / 대한법의학회지

Recently many forensic scientists are trying to use the DNA 'barcode' region (upstream portion of mitochondrial cytochrome oxidase subunit I) to identify the species of forensically important fly species. We have analyzed to compare their sequences of the 'barcode' region for twelve blow fly species[A. grahami, C.lata, C. vicina, H.ligurriens, L. ampullaceal, L. Caesar, L. illustris, P. sericata, P. regina, T. calliphoroides, C. megacephala, C. pinguis] collected from the rural and urban regions in Korea. Intra- and interspecies sequence divergences were calculated as 0~0.9% and 0.9~11.4%, respectively. Phylogenetic trees were drawn with Mega 3.1 and Network 4.20 programs. The result illustrates that each genus is grouped as monophyletic group except for T. calliphoroides and all the same species were monophyletic group. This suggests that the 'Barcode' region of COI gene could be a marker for identification of necrophagous blow fly species. But the two closely related species, L.illustris and L.caesar show little differences from each other. Therefore more individuals of these species should be examined for population study.

Comparison of Mitochondrial Cytochrome Oxidase Subunit I (CO I) Sequences of Five Blow Fly Species in Korea / 대한법의학회지

In criminal investigations, the accurate identification of specimens must be a vary important procedure in the estimation of post-mortem interval(PMI) using insect specimens. However, the morphological-based identification method has many limitations, as species identification for immature stages of many species being difficult or impossible, and more convenient methods are needed to identify necrophagopus fly species. So, many authors have proposed DNA-based methods for identifying fly specimen because of identifying all life stages of carrion flies. In this study, we sequenced a part of mitochondrial cytochrome oxodase subunit I (COI) for each five blow fly species [Hemipyrellia ligurriens, Lucilia illustris, Phaenicia sericata, Chrysomya. megacephala, Chrysomya pinguis] collected from the rural and urban regions in Korea, and compared 400 nucleotides of one species with those of another species. Percent similarity of sequence compared was highest value between Ch. pinguis and Ch. megacephala (97.8%), and lowest one between H. ligurriens and Ch. pinguis(89.2%). Maximun intraspecific variation was observed in L. illustris (0.5%). In conclusion, the experimental results indicate that sequence analyses of more necrophagous flies collected from various regions of Korea should be performed to construct a database of mitochondrial CO I of necrophagous fly species.