NR3C1 and major depressive disorder: Further, single nucleotide polymorphisms and expression levels of the genes encoding GR (NR3C1) and MR (NR3C2) have been associated with depression (Webster et al., 2002; van Rossum et al., 2006; Klok et al., 2011a,b; Medina et al., 2013; Qi et al., 2013).