the Carter effect. This has been reported for several complex traits (Kruse et al. 2012; Kantarci et al. 2006). Fourth, we performed a sex-stratified genetic correlation analysis with other traits which may play a role in OCD development (e.g. brain volumes), are sexually-differentiated (e.g. autism, Tourette syndrome, attention deficit hyperactivity disorder, etc.), or are known to show differences in comorbidity between males and females with OCD (e.g. smoking, eating disorders, and reproductive behavior). Here, we present the first genome-wide assessment of the sex-specific genetic architecture of OCD utilizing the largest OCD dataset currently available. We also provide best practices for sex-stratified analysis which can be adopted in future studies of OCD and other phenotypes.
