The associations between rs1229984 and maternal characteristics known to be generally related to alcohol drinking were analyzed to empirically assess the specificity of the rs1229984-alcohol intake association. For maternal socio-economic status or education, smoking habits, BMI and age at delivery there is no evidence of association; nor is there any association with alcohol drinking behavior of the partner (Supplementary Material, Table S4). Similarly, since drinking cessation in the first trimester may be due to symptoms of nausea and various food aversions experienced in early pregnancy, we looked at these in association with rs1229984 genotype. There is little evidence of association with nausea or developing aversion to any of the following: coffee, tea, colas or cigarettes (Supplementary Material, Table S5).
