Dads who aren't.

This article cites a study conducted by researcher Mark Bellis and his colleagues at Liverpool John Moores University, Great Britain, and published in the "Journal of Epidemiology and Community Health." Bellis says it is increasingly likely that such results will spill out by accident as genetic tests for predisposition to disease spread and through the increasing use of DNA evidence in courts. Adding to the problem is the rise of commercial DNA testing to resolve paternity disputes.