The metabolic genophenotypes of the CYP enzymes CYP2D6, CYP2C19, and CYP2C9 can be classified as normal metabolizer (NM), intermediate metabolizer (IM), poor metabolizer (PM), or ultra-rapid metabolizer (UM), and patients with AD who were classified as NMs or IMs responded significantly better to current treatments for depression and anxiety than those who were classified as PMs or UMs [41]. The gene discussed is CYP2C19; the disease is major depressive disorder.