Internal validation of the RapidHIT^® ID system

Area of Science:

• Forensic Science
• Genetics
• Molecular Biology

Background:

• Traditional forensic DNA analysis relies on skilled geneticists and dedicated labs for short tandem repeat (STR) profiling.
• Increased demand for DNA profiling, including arrestees, necessitates efficient and accessible methods.
• The Rapid DNA (RDNA) platform, RapidHIT ID, provides a fully automated solution for rapid DNA profiling.

Purpose of the Study:

• To validate the performance and limitations of the RapidHIT ID platform for forensic DNA analysis.
• To assess the reliability and concordance of STR profiles generated by the RDNA system.
• To determine the suitability of the RapidHIT ID for deployment in non-laboratory environments.

Main Methods:

• Internal validation studies using four early-production RapidHIT ID units.
• Analysis of reference buccal swabs for short tandem repeat (STR) profiling.
• Evaluation of the impact of inhibitors and substrate on typing success.
• Assessment of contamination and system failure recovery.

Main Results:

• Reliable and concordant STR profiles were consistently obtained from reference buccal swabs.
• No contamination was observed during the validation studies.
• The first-pass success rate was 72%, increasing to 90% with manual interpretation.
• Inhibitors did not affect typing, but substrate type impacted success.

Conclusions:

• The RapidHIT ID system is a robust and reliable tool for generating complete STR profiles.
• The platform can be utilized in forensic DNA typing laboratories or decentralized settings by trained personnel.
• The system's ability to re-analyze samples in case of failure enhances its efficiency and reduces sample consumption.