SLC6A3 and Alzheimer disease: Moreover, peripheral DAT promoter methylation state may merit further investigation as a potential biomarker in AD patients as it (1) was greater in AD patients versus HCs, (2) was a predictor of alcohol craving in AD patients, (3) showed a trend towards predicting relapse 1 year after abstinence and (4) was associated with amygdala cue reactivity in patients with low depression scores.