There are several low frequency variants of ALDH1A1 that have been nominally associated with alcoholism-related phenotypes, including ALDH1A*2, a 17 bp promoter deletion, and ALDH1A*3, a 3 bp promoter insertion5 that showed a weak trend toward association with alcoholism in African Americans (Spence et al., 2003). ALDH1A1*2 variant was reported to be associated with higher consumption and increased risk for AD among Trinidadians of Indian descent (Moore et al., 2007), but in Mission Indians it showed the opposite direction (Ehlers et al., 2004), and there was no association with drinking in young adult students of Asian background in the US (Otto et al., 2013). An uncommon intronic variant, rs8187974 was nominally associated with both DSM-IV AD and maxdrinks in European Americans (Sherva et al., 2009). Three SNPs were nominally associated with an alcohol consumption score factor in European American women (Agrawal et al., 2011), and several with problem drinking and AD in European populations (Lind et al., 2008). None have shown up in GWAS. Taken together, the evidence that variants affect AD or drinking behavior is weak.
