Study limitations included the risk of population stratification associated with the case-control design, use of psychiatrically unscreened blood donors as the control group, reduced sample size of participants with certain OCD subphenotypes and tested polymorphisms limited to 3' UTR and exon 13 of GRIN2B.
Although preliminary and requiring replication in larger samples, these results provide evidence that GRIN2B may be associated with susceptibility to OCD.