There is severe intellectual disability, in combination with seizures. Motor development is usually severely delayed. Eye abnormalities include choroidal hypoplasia, retinal degeneration, optic nerve hypoplasia, severe myopia and glaucoma.
Muscle-eye-brain disease is caused by a fault in O-mannosyl glycan synthesis.
It is an inherited autosomal recessive disease with marked phenotypic variability. The founder mutation is in the Finnish population (POMGNT1 mutations are most common).
- cerebral hemispheres
- midline structures
- infratentorial structures
- cerebellar polymicrogyria +/- multiple subcortical cerebellar cysts
- cerebellar vermian and pontine hypoplasia
- malformed tectal plate, fused midbrain superior and inferior colliculi
Treatment and prognosis
No curative treatment is available. Management is supportive.