Hippocampal tissue from 20 alcoholics and 19 controls, all of European background (6 females in each group), was obtained from the New South Wales Tissue Resource Centre at the University of Sydney, Australia (Sheedy et al., 2008). Supplemental Table S1 describes the samples used. Total RNA was extracted using TRIzol® Reagent (Invitrogen; Carlsbad, CA) following a modified protocol with twice as much TRIzol® per gram of tissue (Edenberg et al., 2005). RNA was further purified using the Qiagen RNeasy mini-kit (Qiagen; Valencia, CA). Quality of the RNA, determined using the Agilent Bioanalyzer (Agilent; Santa Clara, CA), did not significantly differ between the 2 groups (mean RIN 6.8, SD 1).
