What are some diseases characterized by progressive loss of the axonal myelin sheath?
Multiple sclerosis is a severe disease caused by progressive destruction of the myelin sheath in the central nervous system. The Guillain-Barré disease is because of destruction of the myelin sheath in the peripheral nervous system caused by autoimmunity (attack by the own immune system). The genetic deficiency in the formation or preservation of the myelin sheath is an X-linked inheritance known as adrenoleukodystrophy. The movie "Lorenzo's Oil" featured a boy with this disease and his father's dramatic search for treatment.