DAT promoter methylation state was elevated in AD patients (mean=15.30±5.14% s.d.)compared with HCs (mean=12.13±3.24% Welch’s t46.7=2.76, P=0.008; Figure 1a), and predicted DAQ craving in AD patients (r2=0.14, P=0.024), but not in HCs (r2=0.043, P=0.427). This evidence concerns the gene SLC6A3 and Alzheimer disease.