Association between genetic variants and risk of obsessive-compulsive disorder.

Obsessive-compulsive disorder (OCD) is a complex multi-gene disorder. In the current study, we genotyped six single nucleotide polymorphisms (SNPs) within MOCOS, NINJ2 and AKT1 genes in a cohort of Iranian patients with this disorder and healthy controls. C allele of rs1057251 has been found to increase risk of OCD (OR (95% CI) =6.39 (4.64-8.79), P value <0.001). This SNP has been associated with risk of OCD in codominant model (OR (95% CI) = 69.53 (25.02-193.21) and 147 (34.2-631.75) for TC and CC genotypes, respectively, P value <0.0001). The rs1057251 was also associated with risk of OCD in dominant (OR (95% CI) = 72.87 (26.28-202.03), P value <0.0001), recessive (OR (95% CI) = 7.43 (2.49-22.19), P value =0.0002), overdominant (OR (95% CI) = 20.2 (11.1-36.76), P value <0.0001) and log-additive (OR (95% CI) = 20.87 (13.83-56.14), P value <0.0001) models. The rs3809263 within NINJ2 was also associated with risk of OCD. The A allele of this SNP has been found to confer risk of OCD (OR (95% CI) =3.28 (2.41-4.48), P value <0.001). This SNP was associated with risk of OCD in codominant (P value <0.0001), dominant (P value <0.0001), overdominant (OR (95% CI) = 9.28 (5.23-16.46), P value<0.0001) and log-additive (OR (95% CI) = 5.25 (3.4-8.1), P value <0.0001) models. Other SNPs were not associated with risk of OCD in any inheritance model. Taken together, rs1057251 and rs3809263 can be considered as risk loci for OCD in Iranian population.