Overview
Myosin storage myopathy (also called hyaline body myopathy) is a rare inherited muscle disease caused by changes in a gene that makes a protein called myosin, which is essential for muscle movement. In this condition, abnormal clumps of myosin build up inside muscle fibers, forming structures called hyaline bodies. These deposits damage the muscle cells over time and prevent them from working properly. The disease mainly affects the skeletal muscles — the muscles you use to move your body. Most people experience slowly progressive muscle weakness, especially in the shoulders, upper arms, and hips. Some individuals also develop breathing difficulties because the muscles that support the lungs can be affected. Heart muscle involvement has been reported in some cases, though it is less common. Symptoms can appear at any age, from infancy to adulthood, and the severity varies widely even within the same family. There is currently no cure for myosin storage myopathy. Treatment focuses on managing symptoms, maintaining mobility through physical therapy, and monitoring breathing and heart function. With careful management, many people can maintain a good quality of life for many years.
Also known as:
Key symptoms:
Slowly worsening muscle weakness, especially in the shoulders and hipsDifficulty lifting arms above the headTrouble climbing stairs or rising from a chairWasting (shrinking) of affected muscles over timeShortness of breath or difficulty breathing, especially when lying downFatigue with everyday activitiesDrooping of the eyelids (ptosis) in some casesDifficulty swallowing in some casesCurved spine (scoliosis) in some individualsFoot deformities such as high archesHeart rhythm problems or weakened heart muscle in some casesReduced exercise tolerance
Variable
Can be inherited in different ways depending on the underlying gene
Variable
Can begin at different ages, from infancy through adulthood
Treatments
No FDA-approved treatments are currently listed for Myosin storage myopathy.
View clinical trials →Clinical Trials
View all trials with filters →No actively recruiting trials found for Myosin storage myopathy at this time.
New trials open frequently. Follow this disease to get notified.
Treatment Centers
8 centersBaylor College of Medicine Rare Disease Center ↗
Baylor College of Medicine
📍 Houston, TX
🏥 NORDStanford Medicine Rare Disease Center ↗
Stanford Medicine
📍 Stanford, CA
🔬 UDNNIH Clinical Center Undiagnosed Diseases Program ↗
National Institutes of Health
📍 Bethesda, MD
🔬 UDNUCLA UDN Clinical Site ↗
UCLA Health
📍 Los Angeles, CA
🔬 UDNBaylor College of Medicine UDN Clinical Site ↗
Baylor College of Medicine
📍 Houston, TX
🔬 UDNHarvard/MGH UDN Clinical Site ↗
Massachusetts General Hospital
📍 Boston, MA
🏥 NORDMayo Clinic Center for Individualized Medicine ↗
Mayo Clinic
📍 Rochester, MN
👤 Mayo Clinic Center for Individualized Medicine
🏥 NORDUCLA Rare Disease Day Program ↗
UCLA Health
📍 Los Angeles, CA
Travel Grants
No travel grants are currently matched to Myosin storage myopathy.
Community
No community posts yet. Be the first to share your experience with Myosin storage myopathy.
Start the conversation →Latest news about Myosin storage myopathy
No recent news articles for Myosin storage myopathy.
Follow this condition to be notified when news becomes available.
Caregiver Resources
NORD Caregiver Resources
Support, advocacy, and financial assistance for caregivers of rare disease patients.
Mental Health Support
Rare disease caregiving can be isolating. Connect with counseling and peer support.
Family & Caregiver Grants
Financial assistance programs specifically for caregivers of rare disease patients.
Social Security Disability
Learn how rare disease patients may qualify for SSDI/SSI benefits.
Questions for your doctor
Bring these to your next appointment
- Q1.Which muscles are most likely to be affected in my case, and how quickly might the weakness progress?,Do I need breathing tests or heart monitoring, and how often should these be done?,Should my family members be tested for the MYH7 gene change?,What physical therapy program would be most helpful for me right now?,Are there any clinical trials or research studies I might be eligible for?,At what point might I need breathing support, and what does that look like?,Are there any activities or exercises I should avoid to protect my muscles?
Common questions about Myosin storage myopathy
What is Myosin storage myopathy?
Myosin storage myopathy (also called hyaline body myopathy) is a rare inherited muscle disease caused by changes in a gene that makes a protein called myosin, which is essential for muscle movement. In this condition, abnormal clumps of myosin build up inside muscle fibers, forming structures called hyaline bodies. These deposits damage the muscle cells over time and prevent them from working properly. The disease mainly affects the skeletal muscles — the muscles you use to move your body. Most people experience slowly progressive muscle weakness, especially in the shoulders, upper arms, and
Which specialists treat Myosin storage myopathy?
1 specialists and care centers treating Myosin storage myopathy are listed on UniteRare, sourced from ClinicalTrials.gov principal investigators, published research, and the NPPES NPI registry.