5-HTTLPR moderates the relation between changes in depressive and bulimic symptoms in adolescent girls: a longitudinal study.

OBJECTIVE Depression and bulimia both are associated with low serotonin levels. We examined whether the serotonin transporter gene (5-HTTLPR) moderates the relation between depressive and bulimic symptoms over time. METHOD Fifty adolescent girls with no current or past Axis I disorder were genotyped for the 5-HTTLPR gene. Twice, 6 months apart, participants completed self-report measures of depressive symptoms and bulimic symptoms. RESULTS The association between change in depressive symptoms and change in bulimic symptoms over time was significantly stronger in girls who are homozygous for the short 5-HTTLPR allele than for girls with at least one long allele. DISCUSSION This finding is consistent with previous studies documenting a relation between depressive and bulimic symptoms in adolescents. Few studies, however, considered the possible role of serotonin linking both disorders. Gaining a better understanding of developmental effects of low serotonin could help to identify high-risk individuals and provide effective prevention and intervention.