Moreover, the lymphocyte protein levels of proBDNF (t = 3.758, P = 0.001, Student’s t-test; Fig. 2a) and p75NTR (t = −2.610, P = 0.014, Student’s t-test; Fig. 2b) were significantly higher in the alcohol dependence group (n = 27) than in the control group (n = 45); while the protein level of sortilin (t = 0.706, P = 0.494, Student’s t-test; Fig. 2c) was not statistically significant between the two groups. This evidence concerns the gene SORT1 and alcohol dependence.