Genetic variant of HTR2A associates with risk of impulse control and repetitive behaviors in Parkinson's disease

Objectives: To determine the role of a serotonin 2A receptor gene (=HTR2A) variant in the development of impulse control and repetitive behaviors in Parkinson's disease. Methods: We performed a genetic association analysis to a cohort of 404 Korean patients with Parkinson's disease who had been enrolled in a previous study. Presence of impulse control and repetitive behaviors was screened using modified version of Minnesota Impulsive Disorders Interview and genotyping for HTR2A c.102T > C was performed using the TaqMan assay. Results: The T allele, which is presumably linked to higher receptor expression, was marginally associated with impulse control and repetitive behaviors in Parkinson's disease; the genetic influence was significantly enhanced in the lower levodopa-equivalent-dose group, increasing the risk by 2.8 and 6.9 times in CT and TT carriers, respectively (p-trend = 0.011). There was no significant interaction between the c.102T > C variant and clinical risk variables such as sex, age at onset, total daily levodopa-equivalent-dose, use of dopamine agonist and daily dose of dopamine agonist. Conclusion: Our data support a possible contribution of genetic variation in the HTR2A to the susceptibility to impulse control and repetitive behaviors in Parkinson's disease. (C) 2011 Elsevier Ltd. All rights reserved.