Charcot Marie Tooth Disease Type 1A
Charcot Marie Tooth (CMT) disease is a group of inherited, progressive and chronic disorders that affect the peripheral nervous system.
CMT type 1A (CMT1A), the most common form of CMT (70%-80% of all CMT1), is a demyelinating peripheral neuropathy caused by the duplication of the PMP22 (peripheral myelin protein) gene on Chromosome 17 leading to the abnormal structure and function of the myelin sheath. It is characterized by distal muscle wasting and weakness, foot deformities, and severe slowing of nerve conduction that effects more than 100,000 people in Europe and the U.S.
The disease is generally slowly progressive with individuals experiencing weakness and atrophy of the muscles of the lower legs beginning in adolescence; later experiencing hand weakness, sensory loss, and foot and leg problems. CMT1A patients usually become symptomatic between age five and 25 years, with <5% of individuals requiring wheelchair dependence. No curative or symptomatic medications have been approved and current treatment options principally consists of supportive care, occupational therapy and surgery.
Duchenne Muscular Dystrophy
Duchenne muscular dystrophy (DMD) is a fatal X-linked progressive degenerative disease caused by mutations in the dystrophin gene that causes progressive muscle weakness, usually leading to death in early adulthood.
DMD is the most common neuromuscular disease of childhood and affects approximately 1 in 3,500 to 5,000 live male births, approximately 15,000 boys are living with the disease in the United States alone and over 200,000 worldwide. Duchenne patients lose muscle function from an early age, motor developmental milestones are delayed in childhood generally leading to wheelchair dependency before their teenage years, the need for assisted ventilation in late teens, and premature death in the third to fourth decade of life.