Evaluation of a rapid DNA process with the RapidHIT® ID system using a specialized cartridge for extracted and quantified human DNA

Abstract

The turn-around time of urgent crime scene DNA samples is often far longer than desired by law enforcement. Crime scene DNA sample processing involves both complex and routine processing steps. Simplification and integration of the routine steps would dramatically improve turn-around time and reduce the risk of operator contamination. Routine DNA extraction and quantitation is readily available. However, PCR amplification and electrophoretic analysis remain largely manual. Rapid DNA Analysis is a hands-free "swab in - profile out" process which consists of automated DNA extraction, amplification, separation, detection, and allele calling without human intervention. RapidHIT^® 200 and RapidHIT ID are rapid DNA systems developed by IntegenX (Pleasanton, CA) and validated for the use of buccal swabs. A new generation of the RapidHIT sample cartridge for RapidHIT ID has been designed and tested which allows the loading of extracted and quantified DNA. RapidHIT EXT sample cartridge allows a user to generate a forensic DNA profile from less than 250 pg of extracted and quantified DNA in less than 90 min with less than one-minute hands-on time. Once the sample is loaded in the RapidHIT EXT sample cartridge, a DNA profile is produced after amplification, detection and automated data analysis. We report on sensitivity, reproducibility, concordance, DNA mixtures and carryover for EXT sample cartridges pre-loaded with GlobalFiler^® Express and AmpFLSTR^® NGM SElect™ Express, (Thermo Fisher Scientific, Waltham, MA) STR chemistries. Purified and quantified DNA from mock crime scene samples were used to demonstrate the utility of these cartridges in an established forensic laboratory.

Keywords: AmpFLSTR(®) NGM SElect™ Express; GlobalFiler(®) Express; Rapid DNA; RapidHIT(®) ID; RapidLINK(®); STR.