DNA by mail: an inexpensive and noninvasive method for collecting DNA samples from widely dispersed populations.

As specific genes are identified that are associated with behavior, it becomes increasingly important for behavioral geneticists to be able to incorporate these genes in their research. Rather than using blood, DNA can be extracted from cheek swabs, which makes it possible to obtain DNA inexpensively by mail from large, widely dispersed individuals. The purpose of this paper is to recommend this technique to the behavioral genetics community and to present results of our use of this technique to obtain DNA by mail for 114 2-year-olds and 116 adults.