| Phenotype details |
newborn period general muscular hypotonia, facial weakness, muscle tendon reflexes absent, motor development delayed, never gained head control; 1y-feeding problems due to weak suck required gavage feeding; MRI cranial 4y-normal except mildly enlarged CSF space; serum CK-levels normal; 5y-muscle biopsy fiber-type 1 atrophy; 10y-myopathic facies, highly arched palate, severe distal muscle weakness, generalized muscle atrophy, scoliosis, ankle contractures, severely retarded motor and mental development; not able to stand, sit, eat, or drink without support; no speech; early brainstem evoked potentials could not be elicited, otoacoustic emissions normal; neurography showed combined axonal and demyelinating motor neuropathy |