Disease Directory Spinal Muscular Atrophy
Neuromuscular

Spinal Muscular Atrophy

Also known as: SMA

Prevalence

1 in 6,000–10,000 live births

Onset

Variable (birth to adulthood depending on type)

Type

Disease

Gene

SMN1

About Spinal Muscular Atrophy

Spinal muscular atrophy (SMA) is a genetic neuromuscular disorder caused by mutations in the SMN1 gene, leading to progressive loss of motor neurons in the spinal cord. It is one of the most common fatal genetic diseases of infancy. Types range from severe infantile-onset (Type 1) to adult-onset (Type 4). Disease-modifying treatments now exist: nusinersen (Spinraza), onasemnogene abeparvovec (Zolgensma), and risdiplam (Evrysdi). Clinical trials remain highly active, especially in gene therapy and next-generation SMN-targeting approaches.

Common Clinical Features

Progressive muscle weakness Loss of motor milestones Hypotonia (low muscle tone) Respiratory difficulties Scoliosis Feeding difficulties Absent deep tendon reflexes Joint contractures

Clinical Trial Eligibility Tips

What to know before applying to Spinal Muscular Atrophy trials.

The SMN1 gene test is the definitive diagnostic — ask your neurologist for genetic confirmation before enrolling in any trial.

SMA trials often stratify by SMN2 copy number — know your copy count as it affects eligibility for many studies.

Newborn screening for SMA is now available in many countries — pre-symptomatic treatment significantly improves outcomes.

Patient Resources

Patient Organization

Cure SMA

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Natural History Registry

SMA Patient Registry (TREAT-NMD)

Join registry ↗

Orphanet

European reference resource for rare diseases

View on Orphanet ↗

NORD

National Organization for Rare Disorders

Search NORD ↗

Find recruiting Spinal Muscular Atrophy trials

Search 500,000+ studies from ClinicalTrials.gov, filtered for Spinal Muscular Atrophy. Updated daily.

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