The Validation of the RapidHIT ID System for Human Identification

Forensic scientists have routinely employed short tandem repeat (STR) typing as a means to identify or exclude individuals that may have left biological evidence at crime scenes. Despite developments in automation of STR typing workflow, the work is time consuming and requires the expertise and resources of a dedicated forensic genetics laboratory. Rapid DNA technology offers a simple, 90-minute swab-to-profile approach to generate STR profiles, requiring minimal training and expertise to operate the system. Use of Rapid DNA technology in the field has been met with some success in identifying victims of natural disasters and determining familial relationships. As Rapid DNA continues to be developed and implemented, validation studies are necessary to ensure the quality of analyses performed by Rapid DNA instruments. A series of studies in accordance with SWGDAM guidelines were designed to test different performance measures of the RapidHIT ID System for Human Identification (Thermo Fisher Scientific). Blood and buccal samples at varying amounts of DNA were collected and subsequently analyzed using the RapidHIT instrument to identify optimal DNA input amounts. Concordance between RapidHIT and capillary electrophoresis-generated profiles served to demonstrate comparability to the current standard in STR typing. Sample retrieval and re-analysis through Rapid DNA technology or other typing methods were tested as this workflow can be useful in both a practical and laboratory setting. The results from this study provide opportunities for protocol and user guide revisions, software improvements, and highlighting parts of instrumentation that can be improved for future models.