Spinal muscular atrophy (SMA) is a genetic disease affecting the central nervous system, peripheral nervous system, and voluntary muscle movement (skeletal muscle). Most of the nerve cells that control muscles are located in the spinal cord, which accounts for the word spinal in the name of the disease.SMA is muscular because its primary effect is on muscles, which don’t receive signals from ...

SMA linked to chromosome 5 (SMN-related), types 0-4 In spinal muscular atrophy (SMA) types 0 through 4, symptoms vary on a continuum from severe to mild based on how much functional SMN protein there is in the nerve cells called motor neurons. (“SMN” stands for survival of motor neuron.) The more SMN protein there is, the later in life symptoms begin and the milder the course of the ...

What causes spinal muscular atrophy (SMA)? SMA is characterized by the loss of motor neurons, nerve cells in the spinal cord. It is classified as a motor neuron disease. What are the genetic causes of SMA? The most common form of SMA (types 1-4) is caused by a defect (mutation) in the SMN1 gene on chromosome 5. (People have two SMN1 genes — one on each chromosome 5). In 94% of all SMA cases ...

SMA linked to chromosome 5 Spinal muscular atrophy (SMA) types 1 through 4 all result from a single known cause — a deficiency of a protein called SMN, which stands for "survival of motor neuron." Deficiency of SMN protein occurs when a mutation (flaw) is present in both copies of the SMN1 gene — one on each chromosome 5. Normally, most of the proteins made from SMN1 genes is full-length ...

MDA is the #1 health nonprofit advancing research, care and advocacy for people living with muscular dystrophy, ... For more information, visit MDA Celebrates FDA Approval of Zolgensma for Treatment of Spinal Muscular Atrophy in Pediatric Patients. In August 2020, the FDA approved risdiplam (brand name Evrysdi*) for the treatment of SMA in ...

The Muscular Dystrophy Association celebrates this new more accessible treatment option for people living with SMA. New York, Wednesday, February 12, 2025 — The Muscular Dystrophy Association (MDA) today celebrates the decision by the US Food and Drug Administration (FDA) to grant approval of a risdiplam (Evrysdi) in tablet form, marking a significant advancement in the treatment of spinal ...

The first steps in diagnosis of a neuromuscular disease are usually an in-office physical examination and family history, with some simple tests to distinguish spinal muscular atrophy (SMA) from similar conditions (such as muscular dystrophy). Muscle weakness and hypotonia should be the first signs that raise suspicion for SMA in babies. Other signs can help to confirm the diagnosis, such as a ...

Spinal muscular atrophy (SMA) is a genetic neuromuscular disorder . affecting approximately . 1 in 10,000. live births. It is estimated to affect roughly . 10,000 children and adults. in the United States, and about . 1 in every 50 Americans. is a genetic carrier. The disease can affect infants and adults of any race or gender. SMA is ...

Spinal-bulbar muscular atrophy (SBMA) is a genetic disorder in which loss of motor neurons — nerve cells in the spinal cord and brainstem — affects the Shop the MDA store for your limited edition 75th anniversary merchandise ... The Muscular Dystrophy Association (MDA) is a qualified 501(c)(3) tax-exempt organization. ©2025, Muscular ...

MDA is the #1 health nonprofit advancing research, care and advocacy for people living with muscular dystrophy, ALS, and related neuromuscular diseases. ... The rare nature of progressive muscle disease like muscular dystrophies, spinal muscular atrophy, ALS, and Pompe, coupled with corresponding gaps in public awareness and scientific ...