BMAL1 and major depressive disorder: Genetic polymorphisms for Arntl have been associated with alcohol consumption, increased risk of alcohol use disorder, and alcohol use disorder with comorbid MDD or bipolar disorder (Kovanen et al., 2010; Sjoholm et al., 2010; Partonen, 2015; Banach et al., 2018), indicating increased ARNTL expression may reflect core genetic factors associated with SUD.