Manhattan plot of the association results across the ADH gene region. The ADH gene locations are shown in the bottom track of this plot generated by loading the PLINK results into IGV. The black rectangle highlights SNP rs991316, which exhibits a much higher significance than the other SNPs in the ADH gene region. No minor allele frequency cutoff was applied. Abbreviations: ALCDep3 = alcohol dependence as defined by DSM-III-R guidelines; ALCDep4 = alcohol dependence as defined by DSM-IV guidelines; ALCDep_Cluster = DSM-IV alcohol dependence within 1 year clustering.