We report on a family with an apparently X-linked neuromuscular disease. Electrophysiologic tests and electron microscopic studies are consistent with the diagnosis of hereditary motor sensory neuropathy type II (HMSN-II), one form of Charcot-Marie-Tooth disease. The manner of inheritance, the observation that males are severely affected from infancy, and the frequent association of deafness and/or mental retardation with the neuromuscular disorder are not usual for HMSN-II and suggest that this family may have a previously undescribed genetic disorder. The peripheral neuropathy did not appear to be linked to the Xg blood group. Minor abnormalities of sensory nerve conduction, electromyography, and hearing were separately identified in female relatives in this family, but were not consistent enough to be useful in the identification of carriers for this gene.

Brainstem auditory evoked potentials (BAEP) were studied in 93 newborns (49 preterm and 44 fullterm) admitted to the neonatal intensive care unit. One group of 42 infants (28-42 wk CA) were considered at low risk for perinatal complications and served to establish the normal ranges of the BAEP parameters (wave I peak latency and wave I-V interwave interval). Two groups of high risk infants were studied during or shortly following clinically significant hyperbilirubinemia (31 infants) or hypoxemia (20 infants). Though statistically significant BAEP abnormalities were found in the high risk infants, these consisted predominantly of wave I latency prolongations in hypoxemic infants (p less than 0.05) indicating dysfunction in peripheral auditory processes. No significant increases in the wave I-V interval (central conduction time) were found in the high risk infants to suggest central auditory dysfunction in the brainstem. These findings are discussed in relation to previous studies of hyperbilirubinemic and hypoxemic infants.