CYP2C19 and major depressive disorder: Current evidence from large genome-wide association studies (GWAS) does not support a causal or enrichment association between CYP2D6 or CYP2C19 variants and psychiatric disorders such as major depressive disorder (MDD) or anxiety disorders (Taylor et al., 2020; Sun et al., 2025; Flint, 2023; Friligkou et al., 2024).