MTM1
Chr XXLRmyotubularin 1
Also known as: CNM, CNMX, MTMX, XLMTM
This gene encodes a dual-specificity phosphatase that dephosphorylates both phosphotyrosine and phosphoserine residues and is required for muscle cell differentiation. Mutations cause X-linked myotubular myopathy (also called X-linked centronuclear myopathy), inherited in an X-linked recessive pattern. The pathogenic mechanism involves disrupted muscle fiber maturation and organization due to loss of phosphatase function.
Definitive — sufficient evidence for diagnostic panels
Population Genetics & Constraint
gnomAD v4 — loss-of-function & missense intolerance
Highly LoF-intolerant (top ~10% of genes)
Moderately missense-constrained (top ~2.5%)
ClinVar Variant Classifications
0 submitted variants in ClinVar
Protein Context — Lollipop Plot
MTM1 · protein map & ClinVar variants
Showing all ClinVar variants across the protein. Search a specific variant to highlight its position.
3D Protein StructureAlphaFold
External Resources
Links to major genomics databases and tools
Clinical Trials
Active and recruiting trials from ClinicalTrials.gov
Study of ASP2957 in Male Participants With X-linked Myotubular Myopathy Who Need Ventilators
RECRUITINGA Study of AT132 in Young Children With X-Linked Myotubular Myopathy (XLMTM)
ACTIVE NOT RECRUITINGA Study to Check Liver Health in Boys With XLMTM, a Serious Genetic Muscle Condition
RECRUITINGMyotubular and Centronuclear Myopathy Patient Registry
RECRUITINGExternal Resources
Links to major genomics databases and tools