Norman-Roberts syndrome: clinical and molecular studies.

We report on a 7-year-old boy with microcephaly, bitemporal hollowing, low sloping forehead, slightly prominent occiput, widely set eyes, broad and prominent nasal bridge, and severe postnatal growth deficiency. Hypertonia, hyperreflexia, seizures, and profound mental retardation were also present. Brain MRI documented partial agyric cortex with patchy pachygyria, colpocephaly, and hypoplasia of corpus callosum and brain stem, which is consistent with the diagnosis of lissencephaly type I grade 2. On the basis of his phenotypic appearance the patient is considered to have the Norman-Roberts syndrome. Molecular studies, performed by means of in situ hybridization and DNA probe analysis, did not demonstrate deletion in the Miller-Dieker/isolated Lissencephaly critical region on the short arm of chromosome 17.