studies of Asian populations but much more difficult in other populations (Li et al. 2011). However, a recent study in which the ADH1B*2 allele was genotyped in several thousand people of European ancestry showed a highly significant protective effect, comparable in magnitude to that in Asians (Bierut et al. 2012). Therefore, the exact population studied, the size of the study, and the exact trait studied all are important to consider when comparing results.
