SPINAL MUSCULAR ATROPHY (SMA) TREATMENT

Spinal muscular atrophy (SMA) is a genetic disease that affects the central nervous system, peripheral nervous system, and voluntary muscle movement, also known as skeletal muscle. A majority of the nerve cells that control muscles are located in the spinal cord, and when the patient’s muscles do not receive signals from those nerve cells, this results in their muscles getting smaller. The cause of spinal muscular atrophy is due to a missing gene that encodes the survival motor neuron (SMN) protein, which is critical to the health and survival of the nerve cells in the spinal cord responsible for muscle contraction (motor neurons).

SMA occurs in nearly 1 in 11,000 births in the United States. The age when SMA symptoms begin tends to correlate with the severity to which motor function is affected. For example, the earlier the age of onset, the greater the impact on the patient’s motor function. Children who display symptoms at birth or in infancy typically have the lowest level of functioning (Type 1). Later-onset SMA patients with a less severe type (Types 2 and 3, and in teens or adults, Type 4) generally tend to have higher levels of motor function. Newborn screening now includes SMA, which enables physicians to identify patients early on.