Disorder of O-mannosylglycan synthesis

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Overview

Disorder of O-mannosylglycan synthesis is a group of rare genetic conditions that affect how the body builds certain sugar chains (called O-mannosylglycans) on proteins. These sugar chains are especially important for a protein called alpha-dystroglycan, which helps connect muscle cells to the surrounding tissue and plays a key role in brain development. When these sugar chains are not made properly, the protein cannot do its job, leading to a range of problems mainly affecting the muscles, brain, and eyes. This group of disorders is sometimes referred to as dystroglycanopathies. The severity can vary widely. In the most severe forms, babies are born with significant brain malformations (such as cobblestone lissencephaly), severe muscle weakness, and eye abnormalities. Milder forms may present later in childhood or even adulthood with progressive muscle weakness resembling limb-girdle muscular dystrophy, with little or no brain involvement. There is currently no cure for these conditions. Treatment focuses on managing symptoms, which may include physical therapy to maintain mobility, respiratory support if breathing muscles are affected, seizure medications if epilepsy develops, and surgical interventions for eye problems or orthopedic complications. A team of specialists is typically needed to provide comprehensive care. Research into gene therapy and other targeted treatments is ongoing but not yet available as standard care.

Key symptoms:

Muscle weakness, especially in the hips and shouldersLow muscle tone (floppy baby)Delayed motor milestones like sitting and walkingIntellectual disability or learning difficultiesSeizures or epilepsyEye abnormalities such as nearsightedness or retinal problemsBrain malformations visible on MRIDifficulty breathing due to weak respiratory musclesElevated creatine kinase levels in blood testsJoint stiffness or contracturesDifficulty swallowing or feeding problems in infancyScoliosis or curved spineHeart problems in some casesSpeech delaysProgressive loss of ability to walk

Inheritance

Autosomal recessive

Passed on when both parents carry the same gene change; often skips generations

Age of Onset

Variable

Can begin at different ages, from infancy through adulthood

Orphanet ↗NORD ↗

Treatments

No FDA-approved treatments are currently listed for Disorder of O-mannosylglycan synthesis.

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No actively recruiting trials found for Disorder of O-mannosylglycan synthesis at this time.

New trials open frequently. Follow this disease to get notified.

Search ClinicalTrials.gov ↗Join the Disorder of O-mannosylglycan synthesis community →

No specialists are currently listed for Disorder of O-mannosylglycan synthesis.

View NORD Rare Disease Centers ↗Undiagnosed Disease Network ↗

Treatment Centers

8 centers
🏥 NORD

Baylor College of Medicine Rare Disease Center

Baylor College of Medicine

📍 Houston, TX

🏥 NORD

Stanford Medicine Rare Disease Center

Stanford Medicine

📍 Stanford, CA

🔬 UDN

NIH Clinical Center Undiagnosed Diseases Program

National Institutes of Health

📍 Bethesda, MD

🔬 UDN

UCLA UDN Clinical Site

UCLA Health

📍 Los Angeles, CA

🔬 UDN

Baylor College of Medicine UDN Clinical Site

Baylor College of Medicine

📍 Houston, TX

🔬 UDN

Harvard/MGH UDN Clinical Site

Massachusetts General Hospital

📍 Boston, MA

🏥 NORD

Mayo Clinic Center for Individualized Medicine

Mayo Clinic

📍 Rochester, MN

👤 Mayo Clinic Center for Individualized Medicine

🏥 NORD

UCLA Rare Disease Day Program

UCLA Health

📍 Los Angeles, CA

Travel Grants

No travel grants are currently matched to Disorder of O-mannosylglycan synthesis.

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Community

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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 specific gene is affected in my child, and what does that mean for the expected disease course?,How often should we have follow-up appointments with each specialist?,What signs of breathing problems should I watch for, and when should I seek emergency care?,Are there any clinical trials or experimental treatments available for this specific type?,What therapies (physical, occupational, speech) should we start now to get the best outcomes?,Should other family members be tested to see if they carry the gene mutation?,What resources or support groups are available for families dealing with this condition?

Common questions about Disorder of O-mannosylglycan synthesis

What is Disorder of O-mannosylglycan synthesis?

Disorder of O-mannosylglycan synthesis is a group of rare genetic conditions that affect how the body builds certain sugar chains (called O-mannosylglycans) on proteins. These sugar chains are especially important for a protein called alpha-dystroglycan, which helps connect muscle cells to the surrounding tissue and plays a key role in brain development. When these sugar chains are not made properly, the protein cannot do its job, leading to a range of problems mainly affecting the muscles, brain, and eyes. This group of disorders is sometimes referred to as dystroglycanopathies. The severity

How is Disorder of O-mannosylglycan synthesis inherited?

Disorder of O-mannosylglycan synthesis follows a autosomal recessive inheritance pattern. Genetic counseling can help families understand recurrence risk and testing options.