DNA from buccal swabs recruited by mail: Evaluation of storage effects on long-term stability and suitability for multiplex polymerase chain reaction genotyping

We provide details of an inexpensive and rapid method for extraction of DNA from buccal swabs (including samples received through the mail) and from a range of other tissue samples. The procedure we have developed provides amounts of DNA adequate for several thousand polymerase chain reactions (PCRs), and we have validated its potential for long-term storage. Samples stored for >4 years are of comparable concentration and provide as robust PCR templates as those tested immediately after extraction. The availability of this technology is of considerable significance in planning DNA banks from population collections and cohorts.