Comparative Study of Five Commercially Available Saliva Collection Kits for DNA Extraction

Background: Obtaining DNA samples through saliva samples is becoming more common, and more companies are responding to this demand with saliva collection/DNA extraction kits. Methods: The University of Pittsburgh's School of Dental Medicine maintains a DNA bank, which our lab helps direct. While we have always used Oragene (DNAGenotek, Kanata, Canada) kits to collect samples in the past, we recently compared 5 alternative kits/methods in an effort to reduce costs while maintaining quality. The kits/methods were: Norgen (Norgen Biotek Corp., Thorold, Canada), Stratec (Stratec Biomedical, Birkenfeld, Germany), DNAgard (Biomatrica, San Diego, CA, USA), Oasis (Oasis Diagnostics, Vancouver, WA, USA), and an in-house protocol for DNA extraction from whole saliva. We compared 7 protocols for extracting DNA from saliva using 5 commercially available kits. We primarily looked at total DNA yield, but also considered cost, ease of sample collection, and complexity of extraction protocol. Results: When compared to the Oragene kits, only Norgen and Startec had comparable DNA yields (30 mu g or more). Oasis was the easiest to use in terms of sample collection. Conclusions: When compared to our whole saliva DNA extraction protocol, all kits had higher yields, shorter extraction time, and easier protocols.