The higher enzyme activity encoded by the polymorphisms ADH1B*2 (Arg48His, rs1229984), ADH1B*3 (Arg370Cys, rs2066702), and the ADH1C*1 haplotype (Arg272Ile350) enables more rapid conversion of ethanol to acetaldehyde, thereby also resulting in the flushing syndrome and also being protective against excessive alcohol consumption and alcoholism [22,23]. Carriers of both the ADH1B*2 and ALDH2*2 alleles have a particularly severe flushing response [22].
