Methods: We undertook a narrative synthesis of the literature focusing on the MED subunits most commonly associated with neurological disorders, including MED1, MED8, MED11, MED12/MED12L, MED13/MED13L, MED14, MED17, MED20, MED23, MED25, MED27, and CDK8. The gene discussed is MED27; the disease is nervous system disorder.