The Val66Met polymorphism at the BDNF gene does not influence Wisconsin Card Sorting Test results in children and adolescents with bipolar disorder.

Objectives: To assess the role of the Val66Met polymorphism at the brain-derived neurotrophic factor (BDNF) gene on the performance of children and adolescents with bipolar disorder [juvenile bipolar disorder (JBD)] on the Wisconsin Card Sorting Test (WCST).

Methods: Children and adolescents were assessed by the K-SADS-PL and a clinical evaluation for BD and comorbid conditions. Manic and depressive symptoms were assessed with the Young Mania Rating Scale and the Children Depression Rating Scale - Reviewed.