With the exception of a recent Australian twin study (23), no other study has explored the association between alcohol intake and variation across the ADH region beyond the classical ADH1B and ADH1C variants. Most of the evidence relating alcohol behavior to ADH variation in non-Asian populations comes from three fine-mapping studies limited to the alcoholism phenotype (37,52,59), whose results confirmed a role for variation in ADH1B (37,52,59), and suggested one for the ADH4 gene (37,52), replicating a previous study (60). The only data on ADH4 comparable with this study is an association signal for maximum number of drinks for rs3762894, independent of rs1229984 (23). We could not replicate this result when looking at binge drinking during pregnancy, however, a full comparison is hindered because effect estimates are not presented in the Australian publication (23).
