150Multiple Epiphyseal Dysplasia (MED) (多發性骨骺發育不全症)
151Multiple Pituitary Hormome Deficiency (MPHD) / Anterior Pituitary Hypoplasia (腦下垂體發育不全症)
152Multiple Sclerosis (MS) (多發性硬化症)
153Multiple System Atrophy (MSA) - Pakinsonian Subtype (多重系統退化症-非典型巴金森症)
154Multiple System Atrophy (MSA) - Type C (多重系統退化症-C型)
155Myasthenia Gravis (MG) (重症肌無力症)
156Myhre Syndrome (Myhre綜合症)