Lack of association of apolipoprotein E polymorphism in obsessive-compulsive disorder

Obsessive-compulsive disorder (OCD) could be considered a neurodevelopmental disorder, from several lines of evidence. One of the most widely studied genes in these disorders is the apolipoprotein E gene, particularly allele 4. We analyzed for association among patients with OCD versus normal controls and cognitively impaired patients. There were no significant differences between OCD probands compared with population controls. However, the cognitively impaired group showed a higher frequency of allele apolipoprotein E gene compared with normal controls and patients with OCD.