Human Saliva and Dried Saliva Spots as Source of DNA for PCR based HLA Typing using a Combination of Taq DNA Polymerase and AccuPrimeTaq Polymerase

Genomic DNA extracted from human saliva samples showed high inter-subject variations in DNA yield, compelling the need to explore a methodology for the accurate quantitation of the extracted genomic DNA. Quantitative assessment of DNA extracted from saliva was achieved using human coagulation factor XIII as an internal control for subsequent downstream applications of amplification of human leucocyte antigen (HLA) genes by PCR. The PCR signals for the HLA target genes, namely, HLA-A, -B, -C , DPB1, DQB1, and DRB1 of exons 2 and 3, improved greatly with the use of a combination of Taq DNA polymerase and AccuPrimeTaq DNA polymerase.  We also describe a new method of using dried saliva spots (DSS) as an alternate source of genomic DNA for HLA typing. PCR-based typing of DNA from human saliva offers a potential method for HLA typing and amplification, and typing of DNA, thus presented, could be applied in forensic science to saliva samples recovered from crime scenes.