Overview
Polyglucosan body myopathy type 1 (PGBM1) is a very rare inherited muscle disease caused by problems with how the body stores and processes glycogen, a form of sugar used for energy. In this condition, abnormal clumps of a substance called polyglucosan accumulate inside muscle cells. These clumps damage the muscle fibers over time, leading to progressive muscle weakness. The disease is caused by mutations in the GYG1 gene, which provides instructions for making a protein called glycogenin-1 that plays a key role in starting the process of building glycogen molecules. Patients with PGBM1 typically develop slowly worsening muscle weakness, often affecting the legs and arms. Some people may also experience exercise intolerance, meaning they tire more easily during physical activity. In some cases, the heart muscle can also be affected, leading to a condition called cardiomyopathy. The severity and age of onset can vary between individuals, but symptoms usually begin in adulthood. There is currently no cure for polyglucosan body myopathy type 1. Treatment focuses on managing symptoms and maintaining quality of life. This may include physical therapy to preserve muscle strength and mobility, cardiac monitoring if the heart is involved, and supportive care from a team of specialists. Research into this condition is ongoing, and understanding of the disease continues to grow as more cases are identified.
Also known as:
Key symptoms:
Progressive muscle weakness in the arms and legsDifficulty walking or climbing stairsExercise intolerance and easy fatigueMuscle wasting over timeHeart muscle problems (cardiomyopathy)Difficulty lifting objectsReduced stamina during physical activityMuscle stiffness or crampingTrouble with balanceShortness of breath with exertion if the heart is affected
Autosomal recessive
Passed on when both parents carry the same gene change; often skips generations
Adult
Begins in adulthood (age 18 or older)
Treatments
No FDA-approved treatments are currently listed for Polyglucosan body myopathy type 1.
View clinical trials →Clinical Trials
View all trials with filters →No actively recruiting trials found for Polyglucosan body myopathy type 1 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 Polyglucosan body myopathy type 1.
Community
No community posts yet. Be the first to share your experience with Polyglucosan body myopathy type 1.
Start the conversation →Latest news about Polyglucosan body myopathy type 1
No recent news articles for Polyglucosan body myopathy type 1.
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.How severe is my condition based on the genetic testing and biopsy results?,Is my heart affected, and how often should I have cardiac check-ups?,What kind of physical therapy or exercise program is safe and beneficial for me?,Are there any clinical trials or research studies I could participate in?,What signs of worsening should I watch for and when should I seek urgent care?,Should my family members be tested for carrier status?,What assistive devices or accommodations might help me maintain independence?
Common questions about Polyglucosan body myopathy type 1
What is Polyglucosan body myopathy type 1?
Polyglucosan body myopathy type 1 (PGBM1) is a very rare inherited muscle disease caused by problems with how the body stores and processes glycogen, a form of sugar used for energy. In this condition, abnormal clumps of a substance called polyglucosan accumulate inside muscle cells. These clumps damage the muscle fibers over time, leading to progressive muscle weakness. The disease is caused by mutations in the GYG1 gene, which provides instructions for making a protein called glycogenin-1 that plays a key role in starting the process of building glycogen molecules. Patients with PGBM1 typic
How is Polyglucosan body myopathy type 1 inherited?
Polyglucosan body myopathy type 1 follows a autosomal recessive inheritance pattern. Genetic counseling can help families understand recurrence risk and testing options.
At what age does Polyglucosan body myopathy type 1 typically begin?
Typical onset of Polyglucosan body myopathy type 1 is adult. Age of onset can vary across affected individuals.
Which specialists treat Polyglucosan body myopathy type 1?
1 specialists and care centers treating Polyglucosan body myopathy type 1 are listed on UniteRare, sourced from ClinicalTrials.gov principal investigators, published research, and the NPPES NPI registry.