Serotonin transporter promoter polymorphism is associated with executive function impairments in patients with obsessive compulsive disorder

© 2016 Informa UK Limited, trading as Taylor & Francis Group.Abstract: Objective: In the present study, we investigate the association between the 5-HTTLPR polymorphism and executive functions in a sample of patients with obsessive compulsive disorder (OCD). Method: A total of 98 unmedicated patients diagnosed with OCD according to DSM-IV criteria and 80 healthy controls were included in this study. The genotype frequencies of 5-HTTLPR polymorphism were compared in OCD and healthy control groups. The four subgroups of OCD and healthy control participants, determined according to having LaLa genotype (high expressing) or S- and/or Lg alleles (low expressing), were also compared using neuropsychological tests of executive functions. Results: The frequency of SLa genotype of 5-HTTLPR polymorphism was found to be higher in patients with OCD compared with healthy controls. The mean scores of conceptual level responses of the Wisconsin Card Sorting Test (WCST) were significantly lower in the OCD-high-expressing subgroup compared with the low-expressing control group. The mean scores of the number of moves of the Tower of London were found to be significantly higher in the OCD-high-expressing subgroup, compared with the high-expressing subgroup of healthy controls. Conclusion: Our findings suggest that the high-expressing variant may be associated with lower performance on some abstraction and planning measures in OCD patients