Disease Directory Bethlem Myopathy
Neuromuscular

Bethlem Myopathy

Also known as: COL6-related myopathy, benign congenital myopathy

Prevalence

Less than 1 in 100,000

Onset

Birth to early childhood; symptoms may be subtle initially

Type

Autosomal dominant (occasionally recessive)

Gene

COL6A1, COL6A2, COL6A3

About Bethlem Myopathy

Bethlem Myopathy is the milder end of the COL6-related myopathy spectrum, caused by heterozygous mutations in one of the three collagen VI genes (COL6A1, COL6A2, or COL6A3). It presents with proximal muscle weakness, joint hyperlaxity in infancy transitioning to contractures in older patients, and characteristic skin changes including follicular hyperkeratosis and keloid scarring. The condition is slowly progressive but most patients remain ambulatory throughout life.

Common Clinical Features

Proximal limb muscle weakness Finger flexion contractures and elbow flexion contractures Joint hyperlaxity in infancy Follicular hyperkeratosis (rough bumpy skin over extensor surfaces) Slowly progressive loss of walking distance Mildly elevated or normal serum creatine kinase Rigid spine in some cases

Clinical Trial Eligibility Tips

What to know before applying to Bethlem Myopathy trials.

COL6-related trials often enrol both Bethlem and Ullrich patients on a spectrum basis — confirm whether your trial distinguishes between subtypes or uses COL6 mutation status alone

Skin biopsy for collagen VI immunofluorescence and fibroblast culture studies may be requested as biomarker endpoints alongside genetic confirmation

Six-minute walk test and hand-held dynamometry are standard endpoints; formal physiotherapy assessment prior to application is advisable

Patient Resources

Patient Organization

Cure CMD (Congenital Muscular Dystrophy)

Visit website ↗

Natural History Registry

CMDIR (Congenital Muscular Dystrophy International Registry)

Join registry ↗

Orphanet

European reference resource for rare diseases (ORPHA:610)

View on Orphanet ↗

NORD

National Organization for Rare Disorders

Search NORD ↗

Find recruiting Bethlem Myopathy trials

Search 500,000+ studies from ClinicalTrials.gov, filtered for Bethlem Myopathy. Updated daily.

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