Pharmacogenetic Testing After a Simple DNA Isolation Method on Buccal Swab Samples

Abstract

To evaluate whether the quality and quantity of DNA isolated from noninvasively obtained buccal swab (BS) samples, using the previously described isolation method for dried blood spot (DBS) samples was satisfactory. From 25 healthy volunteers, DBS samples were obtained by the capillary finger prick method and BS samples were obtained by rubbing a sterile, dry cotton swab against the inside of their cheek. Thereafter, DNA was isolated. In addition, the quantity of the obtained DNA was measured and melting curve analyses for both sampling methods were performed to establish the quality of the obtained DNA from both the DBS and BS samples. The derivative melting curves of the DNA samples obtained from the capillary blood and BS were comparable and highly reproducible. The mean DNA concentrations measured were 16.0 ng/microl (12.6-19.4 ng/microl) and 70.2 ng/microl (57.3-83.1 ng/microl), respectively, for the DBS and BS samples (p < 0.001). The DBS DNA isolation method appeared to be extremely useful to discriminate between genotypes. This expands the possibilities of this quick and easy DNA isolation procedure. In particular, the noninvasive BS sampling method appeared to be a good alternative to invasive sampling methods.