Forensic entomology applies insect evidence to legal problems such as the estimation of minimum postmortem interval (mPMI). For this purpose, knowledge of the insect fauna that are attracted to human cadavers in each geographic region is a prerequisite. Despite many studies investigating the insect fauna attracted to meat, there has been no survey of the entomofauna on human cadavers in the East Asian temperate climate zone, particularly in Korea. Therefore, this study reports the entomofauna collected from medicolegal autopsies in northeastern Seoul and its suburbs. Insect samples were collected from 35 medicolegal autopsies in 2010, 2011, and 2013. Molecular and morphological methods were utilized for taxonomic identification. Among 1398 individual samples belonging to 3 orders, 13 families, 18 genera, and 32 species, the dominant family and species were Calliphoridae and Lucilia sericata, respectively. Despite its limited scale, this study provides a snapshot of the general entomofauna that are attracted to human cadavers in this region.

Sarcophaga peregrina (flesh fly) is a frequently found fly species in Palaearctic, Oriental, and Australasian regions that can be used to estimate minimal postmortem intervals important for forensic investigations. Despite its forensic importance, the genome information of S. peregrina has not been fully described. Therefore, we generated a comprehensive gene expression dataset using RNA sequencing and carried out de novo assembly to characterize the S. peregrina transcriptome. We obtained precise sequence information for RNA transcripts using two different methods. Based on primary sequence information, we identified sets of assembled unigenes and predicted coding sequences. Functional annotation of the aligned unigenes was performed using the UniProt, Gene Ontology, and Kyoto Encyclopedia of Genes and Genomes databases. As a result, 26,580,352 and 83,221 raw reads were obtained using the Illumina MiSeq and Pacbio RS II Iso-Seq sequencing applications, respectively. From these reads, 55,730 contigs were successfully annotated. The present study provides the resulting genome information of S. peregrina, which is valuable for forensic applications.

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To estimate the postmortem interval (PMI) by using entomological evidence, species identification of forensically important flies is mandatory. However, the traditional species identification method, which relies on the key morphological features of adult flies, is not always available to investigators and has limitations to the immature samples. Because of these limitations, species identification using DNA sequences has long been an issue in the field of forensic entomology. In this review, I have briefly described the basic principles of molecular species identification and phylogenetic analysis and their applications in forensic entomology. I also recommend an experimental and statistical method to identify unknown fly samples obtained from the field.

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In the present study, the complete mitochondrial genome of a blowfly Calliphora nigribarbis has been sequenced and analyzed. The length of complete the mitochondrial genome is 16,279 bp, with 39.50% A, 13.20% C, 9.30% G, and 38.0% T nucleotide distribution. The complete mitochondrial genome consists of 13 protein-coding genes, 22 transfer RNAs, and 2 ribosomal RNAs likewise the most metazoan mitochondrial genomes. Furthermore, phylogenetic relationships of C. nigribarbis in the subfamily Calliphorinae investigated. The results suggested that C. vomitoria is the most related species to C. nigribarbis and the genus Calliphora is not monophyletic. This study provides the first complete mitochondrial genome sequence for the species.

Estimation of postmortem interval (PMI) is paramount in modern forensic investigation. After the disappearance of the early postmortem phenomena conventionally used to estimate PMI, entomologic evidence provides important indicators for PMI estimation. The age of the oldest fly larvae or pupae can be estimated to pinpoint the time of oviposition, which is considered the minimum PMI (PMImin). The development rate of insects is usually temperature dependent and species specific. Therefore, species identification is mandatory for PMImin estimation using entomological evidence. The classical morphological identification method cannot be applied when specimens are damaged or have not yet matured. To overcome this limitation, some investigators employ molecular identification using mitochondrial cytochrome c oxidase subunit I (COI) nucleotide sequences. The molecular identification method commonly uses Sanger's nucleotide sequencing and molecular phylogeny, which are complex and time consuming and constitute another obstacle for forensic investigators. In this study, instead of using conventional Sanger's nucleotide sequencing, single-nucleotide polymorphisms (SNPs) in the COI gene region, which are unique between fly species, were selected and targeted for single-base extension (SBE) technology. These SNPs were genotyped using a SNaPshot® kit. Eleven Calliphoridae and seven Sarcophagidae species were covered. To validate this genotyping, fly DNA samples (103 adults, 84 larvae, and 4 pupae) previously confirmed by DNA barcoding were used. This method worked quickly with minimal DNA, providing a potential alternative to conventional DNA barcoding. Consisting of only a few simple electropherogram peaks, the results were more straightforward compared with those of the conventional DNA barcoding produced by Sanger's nucleotide sequencing.

Identification of insect species is an important task in forensic entomology. For more convenient species identification, the nucleotide sequences of cytochrome c oxidase subunit I (COI) gene have been widely utilized. We analyzed full-length COI nucleotide sequences of 10 Muscidae and 6 Sarcophagidae fly species collected in Korea. After DNA extraction from collected flies, PCR amplification and automatic sequencing of the whole COI sequence were performed. Obtained sequences were analyzed for a phylogenetic tree and a distance matrix. Our data showed very low intraspecific sequence distances and species-level monophylies. However, sequence comparison with previously reported sequences revealed a few inconsistencies or paraphylies requiring further investigation. To the best of our knowledge, this study is the first report of COI nucleotide sequences from Hydrotaea occulta, Muscina angustifrons, Muscina pascuorum, Ophyra leucostoma, Sarcophaga haemorrhoidalis, Sarcophaga harpax, and Phaonia aureola.