SEROTONIN TRANSPORTER AND SEASONAL-VARIATION IN BLOOD SEROTONIN IN FAMILIES WITH OBSESSIVE-COMPULSIVE DISORDER

The serotonin transporter (HTT) is a candidate gene for obsessive-comp ulsive disorder (OCD) that has been associated with anxiety-related tr aits. The long (l) and short (s) variants of the HTT promoter have dif ferent transcriptional efficiencies. HTT promoter genotype and blood 5 -HT concentration were examined in 70 subjects from 20 families ascert ained through children and adolescents with a DSM-III-R diagnosis of O CD. The HTT promoter variant had a significant effect on blood 5-HT co ntent. Subjects with the l/l and l/s genotypes had significantly highe r blood 5-HT levels than did those with the s/s genotype. There was a significant interaction between HTT promoter genotype and seasonal var iation in blood 5-HT content, with significant seasonal differences in 5-HT occurring only in the subjects with the l/l genotype. Further st udies of the regulation of HTT gene expression are indicated. (C) 1998 American College of Neuropsychopharmacology. Published by Elsevier Sc ience Inc.