Overview
Steinert myotonic dystrophy, also known as myotonic dystrophy type 1 (DM1) or Steinert disease, is the most common form of adult-onset muscular dystrophy. It is caused by an abnormal expansion of a CTG trinucleotide repeat in the DMPK gene on chromosome 19q13.3. The number of repeats correlates broadly with disease severity and age of onset, and the expansion tends to increase across generations, a phenomenon known as genetic anticipation. Myotonic dystrophy type 1 is a multisystem disorder. The hallmark features include progressive skeletal muscle weakness and wasting (particularly affecting the face, neck, and distal limbs), myotonia (difficulty relaxing muscles after contraction), and cataracts. The disease also commonly affects the heart, causing conduction defects and arrhythmias that can be life-threatening. Other frequently involved systems include the endocrine system (insulin resistance, hypogonadism, thyroid dysfunction), the gastrointestinal tract (dysphagia, constipation), the central nervous system (excessive daytime sleepiness, cognitive impairment, apathy), and the respiratory system (respiratory muscle weakness, sleep-disordered breathing). A severe congenital form can present at birth with profound hypotonia, respiratory failure, and intellectual disability. There is currently no cure or disease-modifying therapy for Steinert myotonic dystrophy. Management is supportive and multidisciplinary, focusing on surveillance and treatment of cardiac conduction abnormalities (which may require pacemaker or defibrillator implantation), management of myotonia with medications such as mexiletine, respiratory support including non-invasive ventilation, cataract surgery, endocrine management, and physical rehabilitation. Regular cardiac monitoring is essential due to the risk of sudden cardiac death. Several therapeutic approaches targeting the underlying RNA toxicity mechanism are under active clinical investigation.
Also known as:
Clinical phenotype terms— hover any for plain English:
Autosomal dominant
Passed on from just one parent; each child has about a 50% chance of inheriting it
Variable
Can begin at different ages, from infancy through adulthood
FDA & Trial Timeline
10 eventsZhenzhen Liu — NA
Sun Yat-Sen Memorial Hospital of Sun Yat-Sen University — PHASE2
Sichuan Baili Pharmaceutical Co., Ltd. — PHASE3
Vertex Pharmaceuticals Incorporated — PHASE2
Shanghai JMT-Bio Inc. — PHASE3
University of Valencia — NA
Sichuan Baili Pharmaceutical Co., Ltd. — PHASE3
Vertex Pharmaceuticals Incorporated — PHASE1, PHASE2
Jiangsu HengRui Medicine Co., Ltd. — PHASE3
Zheng Yabing — PHASE2
Data sourced from FDA regulatory filings and ClinicalTrials.gov. Updated periodically.
Treatments
No FDA-approved treatments are currently listed for Steinert myotonic dystrophy.
5 clinical trialsare actively recruiting — trials can provide access to cutting-edge therapies.
View clinical trials →Rare Disease Specialist
Rare Disease Specialist
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 Steinert myotonic dystrophy.
Community
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Start the conversation →Latest news about Steinert myotonic dystrophy
Disease timeline:
New recruiting trial: A Study of BL-M07D1 Versus T-DM1 in the Adjuvant Treatment of HER2-positive Breast Cancer With Residual Invasive Cancer After Neoadjuvant Therapy
A new clinical trial is recruiting patients for Steinert myotonic dystrophy
New recruiting trial: A Phase II Study of Tucatinib and Ado-trastuzumab Emtansine (T-DM1) in Patients With HER2-positive Metastatic Solid Tumors and Metastases to Brain (TUCATEMEB)
A new clinical trial is recruiting patients for Steinert myotonic dystrophy
New recruiting trial: Herombopag Treated T-DM1 Induced Platelet Reduction
A new clinical trial is recruiting patients for Steinert myotonic dystrophy
New recruiting trial: A Phase III, Active-Controlled Study of SHR-A1811 Versus Trastuzumab Emtansine (T-DM1) in HER2-Positive Primary Breast Cancer Participants With Residual Invasive Disease Following Neoadjuvant Therapy
A new clinical trial is recruiting patients for Steinert myotonic dystrophy
New recruiting trial: Adjuvant Therapy Choice for Non-pCR HER2 Positive Early Breast Cancer After Neoadjuvant Therapy
A new clinical trial is recruiting patients for Steinert myotonic dystrophy
New recruiting trial: ATEMPT 2.0: Adjuvant T-DM1 vs TH
A new clinical trial is recruiting patients for Steinert myotonic dystrophy
New recruiting trial: JSKN003 Versus Trastuzumab Emtansine (T-DM1) for HER2-Positive, Advanced Breast Cancer
A new clinical trial is recruiting patients for Steinert myotonic dystrophy
New recruiting trial: Tolerability and Efficacy of Adjuvant T-DM1 in Patients with HER2 Positive Breast Cancer After Incomplete Pathological Response to Neoadjuvant Chemotherapy Including Anti-HER2 Agents.
A new clinical trial is recruiting patients for Steinert myotonic dystrophy
New recruiting trial: Adjuvant Chemoradiation and Biomarkers of Response in High-risk Breast Cancer
A new clinical trial is recruiting patients for Steinert myotonic dystrophy
New recruiting trial: Trastuzumab Emtansine (T-DM1) in HER2-positive Breast Cancer Patients With Progressive Disease After TKIs or HP Therapy
A new clinical trial is recruiting patients for Steinert myotonic dystrophy
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.
Common questions about Steinert myotonic dystrophy
What is Steinert myotonic dystrophy?
Steinert myotonic dystrophy, also known as myotonic dystrophy type 1 (DM1) or Steinert disease, is the most common form of adult-onset muscular dystrophy. It is caused by an abnormal expansion of a CTG trinucleotide repeat in the DMPK gene on chromosome 19q13.3. The number of repeats correlates broadly with disease severity and age of onset, and the expansion tends to increase across generations, a phenomenon known as genetic anticipation. Myotonic dystrophy type 1 is a multisystem disorder. The hallmark features include progressive skeletal muscle weakness and wasting (particularly affecting
How is Steinert myotonic dystrophy inherited?
Steinert myotonic dystrophy follows a autosomal dominant inheritance pattern. Genetic counseling can help families understand recurrence risk and testing options.
Are there clinical trials for Steinert myotonic dystrophy?
Yes — 5 recruiting clinical trials are currently listed for Steinert myotonic dystrophy on UniteRare. See the clinical trials section on this page for phase, sponsor, and site details sourced from ClinicalTrials.gov.
Which specialists treat Steinert myotonic dystrophy?
25 specialists and care centers treating Steinert myotonic dystrophy are listed on UniteRare, sourced from ClinicalTrials.gov principal investigators, published research, and the NPPES NPI registry.