By sampling individuals with OCD from the Swedish population, as well as a larger sample of unaffected (control) individuals, we were able to address these questions. Our analyses of over 2000 individuals diagnosed with OCD and twofold more unaffected individuals, each genotyped across their genome via > 400,000 SNPs, yielded an OCD heritability estimate of 29% (SE=4%), a robust estimate (Table 3).
