Although the labeling of MAO-B-inhibitors in the FORTA list appears to be somewhat drastic, they should be used with circumspection in geriatric PD patients because of the potential interactions, their limitation in the liver (all MAO-B-inhibitors) and renal dysfunction (selegiline), and the risk of other adverse effects (e.g. ulcers for selegiline) (Glavin et al. 1986; Anttila et al. 2005; Klietz et al. 2019). The gene discussed is MAOB; the disease is Parkinson disease.