Why are some psychiatric illnesses, like anxiety and depression, on the increase? Could conditions, like attention deficit hyperactivity disorder, or ADHD, confer an evolutionary advantage? And is it ethical to screen babies for future brain conditions? We report from the Cambridge Neuroscience Seminar.
Certainly in fiction, some mental disorders are portrayed as conferring an "advantage", at least to some individuals.
I dont see how that could work/help (re: O.P. - Could genetic tests help diagnose people who are at risk of developing psychiatric conditions and catch them before they are ill?)
Point taken, however the thread I was replying to (the original heading before the two were merged) was specifically;