Short answer · Medically reviewed summary · Last updated: 2026-05-08
Freeman Sheldon Syndrome is an extremely rare genetic disorder, with fewer than 100 cases documented in medical literature worldwide, though this number likely underestimates the true prevalence due to frequent underdiagnosis. It is classified as an ultra-rare condition, and while the exact global incidence remains unknown, it is known to affect males and females equally across all ethnic groups. Is Freeman Sheldon Syndrome considered a rare disease? Yes, Freeman Sheldon Syndrome is classified as an ultra-rare condition.
What is the prevalence of Freeman Sheldon Syndrome?
Prevalence of Freeman Sheldon Syndrome: how many people are affected worldwide, differences by sex and region, with sources.
Freeman Sheldon Syndrome is an extremely rare genetic disorder, with fewer than 100 cases documented in medical literature worldwide, though this number likely underestimates the true prevalence due to frequent underdiagnosis. It is classified as an ultra-rare condition, and while the exact global incidence remains unknown, it is known to affect males and females equally across all ethnic groups.
Is Freeman Sheldon Syndrome considered a rare disease?
Yes, Freeman Sheldon Syndrome is classified as an ultra-rare condition. Because it is a form of distal arthrogryposis, it is often underdiagnosed or misidentified, making it difficult for researchers to establish precise global prevalence statistics. Currently, our DiseaseMaps.org community includes 32 people with Freeman Sheldon Syndrome, providing a vital, real-world perspective that highlights how rare this condition truly is in the general population.
What are the key epidemiological characteristics of Freeman Sheldon Syndrome?
Understanding the distribution of Freeman Sheldon Syndrome involves looking at several clinical factors:
- Gender Distribution: There is no documented predilection for one sex; Freeman Sheldon Syndrome affects males and females with equal frequency.
- Age of Onset: This is a congenital condition, meaning symptoms are present at birth (pediatric onset), and the condition persists throughout the patient's lifespan.
- Geographic/Ethnic Variation: No specific geographic or ethnic clusters have been identified; cases appear to be distributed globally.
- Diagnostic Challenges: Many individuals may go undiagnosed due to the subtle nature of some clinical features or confusion with other types of arthrogryposis.
How is Freeman Sheldon Syndrome inherited?
Freeman Sheldon Syndrome is typically caused by mutations in the MYH3 gene. It can be inherited in an autosomal dominant pattern, though many cases occur as "de novo" (spontaneous) mutations where neither parent carries the gene. Because it is so rare, accurate genetic counseling is essential for families navigating a diagnosis of Freeman Sheldon Syndrome.
Next steps
- Consult with a clinical geneticist to confirm a diagnosis through molecular genetic testing.
- Join the Freeman Sheldon Syndrome community on DiseaseMaps.org to connect with others sharing similar experiences.
- Maintain regular follow-ups with a multidisciplinary team, including orthopedic surgeons and speech pathologists.
Medical disclaimer: This information is for educational purposes and should not replace professional medical advice, diagnosis, or treatment.
References
- Orphanet: Freeman-Sheldon syndrome (ORPHA:323)
- NIH GARD: Freeman-Sheldon syndrome
- OMIM: Freeman-Sheldon Syndrome (Entry #193700)
- National Organization for Rare Disorders (NORD): Freeman-Sheldon Syndrome
