Assessment of Human DNA and Y-DNA Quantity in Blow Fly Larvae Cultured on Human Blood: Evaluation of Utility for Identification and Forensic Reporting in Sexual Offense Cases

Background/Objectives: Forensic entomology remains an underutilized discipline within forensic medicine, particularly in Poland, where it is primarily applied to post-mortem interval (PMI) estimation. Recent studies indicate that insect-derived material may also hold value in the identification of human remains. Methods: In this pilot study, we assess whether blow fly larvae fed on human blood retain amplifiable human DNA, including Y-DNA. Larvae were reared on blood obtained from four volunteers and collected at the third instar stage seven days after oviposition. Human DNA quantification, degradation assessment, and STR/Y-STR profiling were performed. Results: Despite the deliberately small, exploratory sample size, all larval samples yielded complete and concordant STR and, where applicable, Y-STR profiles matching the respective reference donors. Conclusions: These preliminary findings indicate the potential utility of larvae as an alternative biological substrate in forensic contexts, particularly when conventional tissues are unavailable or degraded. However, the results should be interpreted cautiously and require validation in larger, systematically controlled studies before any routine forensic application can be recommended.