None of the other substance dependence covariates displayed statistically significant association with rs13273442. Alcohol dependence is common in the European American subjects (37.8%, N=1298), and hence we expect this meta-analysis to be well powered to detect association to this substance. The European ancestry meta-analysis estimated OR for alcohol, adjusted for all other substances, is a modest 1.05 (p=0.59), and the odds ratios point estimates in the different studies range from protective (0.82 for FSCD) to risk (1.31 for COGA). Similarly, there is no clear genetic contribution to cocaine or marijuana dependence (OR=1.17 and 0.87, respectively), but the power to detect an association for these substances is reduced due to the smaller number of dependence diagnoses (16.8% (N=578) and 15.8% (N=541), respectively).
