IN THIS issue of the ARCHIVES, De Jonghe and colleagues1
describe a family with autosomal dominant hereditary motor and sensory neuropathy (HMSN). Whereas the proband had bilateral pes cavus, slight peroneal weakness, and loss of Achilles reflexes, 12 relatives had nerve conduction velocities (NCVs) in the demyelinative range but were without pes cavus or other neurologic findings. Nerve biopsy specimens in the proband showed segmental demyelination, remyelination, and considerable loss of large myelinated axons. Molecular genetic and linkage studies excluded all known HMSN loci.