Dominantly inherited peroneal muscular atrophy (hereditary motor and sensory neuropathy type I) in infancy and childhood.

A detailed clinical and electrodiagnostic study has been undertaken of demyelinating polyneuropathy in 14 children (9 male, 5 female) from 11 sibships and their parents. The onset of symptoms was before the age of 2 years in 12 of the 14 children, and the condition in all cases was nonprogressive or very slowly progressive. In each case one of the parents had a slow motor nerve conduction velocity. Five of the 11 affected parents were completely asymptomatic. Electrodiagnostic studies in both parents of all children with demyelinating peripheral neuropathy are thus important to identify the dominantly inherited form of the disease.