PURPOSE: To investigate the radiologic characteristics of the clinical progressive encephalopathy with edema, hypsarrhythmia, and optic atrophy (PEHO) symptom complex. This complex is nonspecific, but within this syndrome, a subgroup with a defined neuropathologic phenotype and apparently autosomal recessive inheritance exists. METHODS: Brain CT or MR studies were performed on 21 patients with the clinical PEHO syndrome. Their previous neuroradiologic studies were re-evaluated. RESULTS: Twelve patients (group A) showed uniform changes with early progressive brain atrophy accentuated infratentorially, and abnormal myelination. The gyral pattern was normal. Brain atrophy of nine patients (group B) differed by being less progressive, supra- rather than infratentorial, and often combined with abnormal gyral formation. CONCLUSIONS: Postmortem studies permitted correlation of radiographic and morphologic findings in three cases. Two autopsied group A patients were compatible with the true PEHO syndrome, while one group B patient was incompatible. Group A seems to correspond to the core group of the PEHO syndrome. During a patient's life, a suggestive diagnosis of the true PEHO syndrome is thus feasible, although neuropathologic studies are needed for a conclusive diagnosis.

Brain Diseases↗

PubMedDate not supplied

Refined mapping of the Cohen syndrome gene by linkage disequilibrium.

The Cohen syndrome is a rare autosomal recessively inherited disorder. Contrary to many case reports published elsewhere, the phenotype is uniform in Finland including nonprogressive mental and motor retardation, typical dysmorphic features, granulocytopenia and marked ophthalmological changes. By linkage analysis in five Finnish multiplex nuclear families, the COH1 locus for the Cohen syndrome was recently assigned to a 10-cM region between loci D8S270 and D8S521 on the long arm of chromosome 8. Here we present results of linkage disequilibrium and haplotype analysis in an extended panel of 16 Finnish COH1 families using new markers localized in the COH1 region. By inferring historical recombinations in conserved haplotypes the COH1 gene was assigned in the region of marker loci D8S1808, D8S1762 and D8S546. Calculations of genetic distances based on linkage disequilibrium suggest that the most likely localization of COH1 is in the immediate vicinity of marker locus D8S1762. Haplotype analysis suggests the occurrence of one main COH1 mutation and possibly one or two rare ones in Finland. This information will be useful in the positional cloning of the gene.

Abnormalities, Multiple↗