Optimizing DNA yield from buccal swabs in the elderly: Attempts to promote buccal cell growth in culture

Participation in genetic studies is often limited by a volunteer's reluctance to donate blood samples. We wished to determine if alternate, less painful, methods to venipuncture could be used to collect cells to provide DNA for genotyping, and whether the cells could be grown in culture for extraction of DNA. Volunteers in the study were comprised of two groups. Nine individuals from a university campus were recruited to provide samples for initial experiments. A second group of 710 twins and singletons from North Carolina and of African-American descent were a part of an ongoing study of age-related traits and participated in collection of buccal swabs via the mail. A protocol was generated that maximizes the recovery of DNA from buccal swabs, which are easier to handle than saline rinses. The DNA recovered is stable over several years, allowing genotype tests at a future date. Attempts to encourage growth of buccal epithelial cells recovered from swabs in tissue culture proved unsuccessful. Buccal swabs work well for the collection of DNA, especially from nonclinic-based volunteers, and can be sent via the mail to the laboratory for DNA extraction. Thus, an inexpensive and efficient method exists for genetic studies of population-based samples.