Spinal Muscular Atrophy: Replacing Assumptions with Understanding

SMA may affect a person’s ability to sit, stand, walk, swallow, cough or breathe. However, its effects, severity and age of onset vary considerably.

Here are some important facts everyone should know.

Myth: SMA affects intelligence

Fact: SMA primarily affects motor neurons and muscle movement, not intelligence.

People living with SMA learn, think, communicate, form relationships and pursue education and careers. Some individuals may use assistive technology to write, speak, study or work, but needing physical support should never be mistaken for a lack of understanding or ability.

Myth: SMA looks the same in everyone

Fact: SMA exists across a broad spectrum.

Symptoms can begin before birth, in infancy, during childhood or in adulthood. One person may need extensive respiratory and mobility support, while another may walk independently and experience milder weakness.

Even people with the same clinical type can have different symptoms, abilities and care needs. A diagnosis alone does not tell someone’s entire story.

Myth: SMA is a form of muscular dystrophy

Fact: Both conditions can cause muscle weakness, but they are not the same.

In SMA, the primary problem begins with motor neurons, the nerve cells that send movement instructions to muscles. When these neurons stop functioning properly, the muscles they control weaken.

Most cases are caused by changes in the SMN1 gene, which prevent the body from producing enough survival motor neuron (SMN) protein.

Myth: Nothing can be done to treat SMA

Fact: Treatment has changed dramatically.

For many years, SMA care focused mainly on managing symptoms and complications. Today, disease-modifying therapies can address the underlying shortage of SMN protein.

Current treatment approaches include:

• Medicines that help the backup SMN2 gene produce more functional SMN protein
• Gene-replacement therapies that deliver a working copy of an SMN gene
• Supportive care such as respiratory care, nutritional support, physical and occupational therapy, orthopedic care, mobility equipment and assistive technology

Treatment is individualized. Eligibility, potential benefits and risks depend on factors including age, symptoms, genetic findings and overall health.

These treatments are not a universal cure, and they may not reverse damage that has already occurred. However, they can slow disease progression, preserve abilities and improve outcomes for many people.

Myth: Medical progress in SMA has been gradual

Fact: The treatment landscape has transformed in less than a decade.

• 2016: The FDA approved the first disease-modifying treatment for SMA.
• 2019: The first gene-replacement therapy was approved for eligible children younger than two.
• 2020: The first oral disease-modifying treatment became available.
• 2025: The FDA approved an additional gene-therapy option for eligible adults and children aged two and older.

This progress has shifted conversations about SMA from symptom management alone toward earlier intervention, longer-term care and new possibilities.

Myth: Doctors should wait for symptoms before treating SMA

Fact: Earlier diagnosis and treatment can be critical.

SMA can damage motor neurons before obvious weakness appears. Once those cells are lost, they may not be recoverable. For this reason, treatment is generally most effective when started as early as possible, sometimes before symptoms develop.

SMA was added to the United States Recommended Uniform Screening Panel in 2018. Newborn screening can identify babies who may have SMA so that confirmatory testing, specialist care and treatment discussions can begin promptly.

A screening result is not itself a diagnosis, but it can provide an essential early warning.

Myth: Medication is the only part of SMA care

Fact: Effective care often involves an entire team.

Depending on an individual’s needs, that team may include neurologists, pulmonologists, physical and occupational therapists, dietitians, orthopedic specialists, genetic counselors and mental-health professionals.

Accessible schools, workplaces, transportation and community spaces also play an important role in supporting independence and participation.

The most important fact:

SMA is part of a person’s life, but it does not define the whole person.

Awareness means learning the science, challenging stereotypes and listening to people with lived experience. It also means recognizing that two people with the same diagnosis may have very different needs, goals and perspectives.

This newsletter provides general educational information and is not a substitute for individualized medical advice.

Learn more from the National Institute of Neurological Disorders and Stroke, HRSA Newborn Screening Information Center and U.S. Food and Drug Administration.