Identification of forensically important sarcophagidae (diptera) based on partial mitochondrial cytochrome oxidase i and II genes

摘要

Entomological evidence is of great importance in forensic cases for postmortem interval calculation. The use of Sarcophagidae (Diptera) for postmortem interval estimation is limited because morphological determination is often hampered because of similar characteristics in the larval, pupal, and even adult stage. To make the species identification more accurate and reliable, DNA-based identification is considered. In this study, we assessed the use of partial mitochondrial cytochrome oxidase I and II genes for discrimination of forensically important Sarcophagidae from Egypt and China [Sarcophaga argyrostoma (Robineau-Desvoidy), Sarcophaga dux (Thomson), Sarcophaga albiceps (Meigen), and Wohlfahrtia nuba (Wiedemann)]. This region was amplified using polymerase chain reaction followed by direct sequencing of the amplification products and using restriction enzymes HinfI and MfeI. Nucleotide sequence divergences were calculated using the Kimura 2-parameter distance model, and a neighbor-joining phylogenetic tree was generated. All examined specimens were assigned to the correct species. Combinations of the restriction enzymes HinfI and MfeI provide different restriction fragment length polymorphism profiles even among 3 sympatric species that belong to the Sarcophaga genus. Therefore, this study demonstrates that the studied partial mitochondrial cytochrome oxidase I and II genes were found to be instrumental for the molecular identification of these forensically important flesh fly species.