Smith‐Magenis syndrome (SMS) is a multiple congenital anomaly, mental retardation (MCA/MR) syndrome associated with deletion of chromosome 17 band p11.2. As part of a multi‐disciplinary clinical, cytogenetic, and molecular approach to SMS, detailed clinical studies including radiographic, neurologic, developmental, ophthalmologic, otolaryngologic, and audiologic evaluations were performed on 27 SMS patients. Significant findings include otolaryngologic abnormalities in 94%, eye abnormalities in 85%, sleep abnormalities (especially reduced REM sleep) in 75%, hearing impairment in 68% (approximately 65% conductive and 35% sensorineural), scoliosis in 65%, brain abnormalities (predominantly ventriculomegaly) in 52%, cardiac abnormalities in at least 37%, renal anomalies (especially duplication of the collecting system) in 35%, low thyroxine levels in 29%, low immunoglobulin levels in 23%, and forearm abnormalities in 16%. The measured IQ ranged between 20–78, most patients falling in the moderate range of mental retardation at 40–54, although several patients scored in the mild or borderline range. The frequency of these many abnormalities in SMS suggests that patients should be evaluated thoroughly for associated complications both at the time of diagnosis and at least annually thereafter. © 1996 Wiley‐Liss, Inc.

The authors review the cases of 116 infants treated consecutively for birth-related brachial plexus injuries. Twenty-eight infants with upper brachial plexus lesions who showed no neurological improvement by 4 months of age were selected for early surgical reconstruction (at a mean age of 5 months). Neurological improvement of the affected arm was observed in more than 90% (p < 0.05) of the children examined longer than 9 months after brachial plexus reconstruction. A conservatively managed control subgroup of 44 children, first examined at less than 3 months of age, demonstrated neurological improvement by 4 months of age and continued to show improvement at 1 year of age. Early surgical reconstruction is recommended for infants with birth-related upper brachial plexus injury who show no neurological improvement by the age of 4 months.

Charcot-Marie-Tooth disease type 1A (CMT1A) is the most common inherited peripheral neuropathy in humans, characterized electrophysiologically by decreased nerve conduction velocities (NCVs). CMT1A is associated with a large submicroscopic DNA duplication in proximal 17p. In this report we demonstrate that a patient with a cytogenetically visible duplication, dup(17)(p11.2p12), has decreased NCV. Molecular analysis demonstrated this patient was duplicated for all the DNA markers duplicated in CMT1A as well as markers both proximal and distal to the CMT1A duplication. These data support the hypothesis that the CMT1A phenotype can result from a gene dosage effect.