Type 2 Diabetes (T2D) alters CYP activities in an isoform-dependent manner: CYP2C19, CYP2B6, and CYP3A4 activities are reduced by 1.5–2-fold, whereas other isoforms may be unaffected or slightly increased (Gravel et al., 2019). The gene discussed is CYP2C19; the disease is type 2 diabetes mellitus.