IEMbase 0352: POMT1-related muscular dystrophy-dystroglycanopathy
Scope
| Field | Value |
|---|---|
| IEMbase ID | 352 |
| Nosology | 18.2.01.06 |
| Gene | POMT1 |
| External IDs | OMIM:236670; OMIM:613555; OMIM:609308; ORPHA:86812 |
| Generated mapping | UNMAPPED; low candidate Dystroglycanopathy.yaml |
| Candidate DisMech targets | Dystroglycanopathy.yaml#MDDG1/POMT1 |
| Review date | 2026-07-07 |
IEMbase phenotype signal
IEMbase represents POMT1-CDG/muscular dystrophy-dystroglycanopathy type A1, type B1, and type C1, an autosomal recessive O-mannosylation disorder. Characteristic rows include buphthalmos, cataract, increased creatine kinase, glaucoma, megalocornea, microphthalmia, pigmentary retinopathy, psychomotor delay, normal sialotransferrins, and Walker-Warburg syndrome.
Additional clinical rows include corpus callosum agenesis on MRI, cerebellar abnormalities, cerebral cortical malformations, cobblestone lissencephaly, dysmorphic features, encephalocele, epilepsy, exophthalmia, fatal evolution before 1 year, hydrocephalus, and muscular dystrophy. Biochemical rows include creatine kinase, matriglycan-specific monoclonal antibody, and sialotransferrins. No treatment rows are present.
DisMech phenotype coverage
The generated UNMAPPED status is a false negative. DisMech has a Dystroglycanopathy file that explicitly covers muscular dystrophy-dystroglycanopathy types A/B/C and the POMT1/MDDG1 subtype. Local mechanism describes defective O-mannosyl glycosylation of alpha-dystroglycan, with POMT1 catalyzing the first O-mannosylation step and producing the full severity spectrum from Walker-Warburg syndrome to limb-girdle muscular dystrophy.
Local coverage includes muscular dystrophy, proximal weakness, neonatal hypotonia, elevated serum CK, cobblestone lissencephaly, intellectual disability, retinal dysplasia, hydrocephalus, seizures, reduced alpha-dystroglycan glycosylation, reduced laminin binding, supportive rehabilitation, genetic counseling, and emerging ribitol/AAV therapeutic context.
Concordance and completeness
Judgement: false negative; resolve to the local dystroglycanopathy POMT1 subtype.
The resources agree on POMT1 identity, autosomal recessive inheritance, O-mannosylation/alpha-dystroglycan biology, Walker-Warburg/type A severe spectrum, muscular dystrophy, elevated CK, cobblestone/cortical brain malformations, hydrocephalus, seizures, ocular involvement, psychomotor delay, and early lethality in the severe end.
Curation actions
- Map this record to
Dystroglycanopathy.yaml, specifically the POMT1/MDDG1 subtype context. - Consider future enrichment with buphthalmos, megalocornea, microphthalmia, cataract, glaucoma, pigmentary retinopathy, corpus callosum agenesis, encephalocele, fatal-before-1-year wording, and matriglycan antibody testing after source verification.
- Treat absent IEMbase treatment rows as incomplete IEMbase coverage rather than a contradiction of local supportive and investigational therapy context.