SLC6A4 and obsessive-compulsive disorder: Initial searches for common, disease-associated coding variation in SLC6A4 failed to indicate common coding variation that could be linked to neurobehavioral disorders including unipolar depression, bipolar disorder (Lesch et al., 1995) and obsessive-compulsive disorder (OCD; Altemus et al., 1996) with a single instance of a coding variant (Leu255Met) found among 67 subjects with major depression (Di Bella et al., 1996) or an additional 74 with OCD, and, due to its rarity and location distant from presumed functional domains, was not further characterized.