An autosomal dominant striatonigral degeneration is present in a family of Portuguese ancestry numbering in excess of 329 persons in eight generations. The illness begins in the second, third, or fourth decade, and progresses for about 15 years with parkinsonian rigidity, spasticity, spastic dysarthria, and abnormalities of eye movement. Neuropathologic findings are severe neuronal loss and astrocytic gliosis in the corpus striatum and substantia nigra, with a moderate neuronal loss in the dentate nucleus of the cerebellum and nucleus ruber of the midbrain. This is a new genetic entity, distinct from other autosomal dominant neurologic disorders such as nigrospinodentatal degeneration, olivopontocerebellar degeneration, dystonia musculorum deformans, Machado's disease, and Huntington's disease.

Submicroscopic deletions involving chromosome 1q43-q44 result in cognitive impairment, microcephaly, growth restriction, dysmorphic features, and variable involvement of other organ systems. A consistently observed feature in patients with this deletion are the corpus callosal abnormalities (CCAs), ranging from thinning and hypoplasia to complete agenesis. Previous studies attempting to delineate the critical region for CCAs have yielded inconsistent results. We conducted a detailed clinical and molecular characterization of seven patients with deletions of chromosome 1q43-q44. Using array comparative genomic hybridization, we mapped the size, extent, and genomic content of these deletions. Four patients had CCAs, and shared the smallest region of overlap that contains only three protein coding genes, CEP170, SDCCAG8, and ZNF238. One patient with a small deletion involving SDCCAG8 and AKT3, and another patient with an intragenic deletion of AKT3 did not have any CCA, implying that the loss of these two genes is unlikely to be the cause of CCA. CEP170 is expressed extensively in the brain, and encodes for a protein that is a component of the centrosomal complex. ZNF238 is involved in control of neuronal progenitor cells and survival of cortical neurons. Our results rule out the involvement of AKT3, and implicate CEP170 and/or ZNF238 as novel genes causative for CCA in patients with a terminal 1q deletion.

Propionic acidemia can present as a pure neurologic disease without acute episodes of massive ketoacidosis. Hyperammonemia may occur after infancy in some patients, presenting as Reye syndrome.

Holoprosencephaly (HPE) is a common malformation of the developing forebrain and midface characterized by incomplete penetrance and variable expressivity. Familial HPE has been reported in many families with autosomal dominant inheritance in some and apparent autosomal recessive inheritance in others. We have examined 125 individuals from nine families with autosomal dominant HPE. Expression in gene carriers varied from alobar HPE and cyclopia through microforms such as microcephaly or single central incisor to normal phenotype. We performed linkage studies by either Southern blot or polymerase chain reaction analyses with DNA markers (D7S22, D7S550, and D7S483) that are deleted from some patients with sporadic HPE and flank a translocation breakpoint in 7q36 associated with HPE. The strongest support for linkage was with D7S22, which was linked with no recombination to autosomal dominant HPE in eight of nine families with a combined logarithm of odds score of 6.4 with an affecteds-only model-free analysis and 8.2 with a reducedpenetrance model and all phenotypes. Close linkage to this region could be excluded in one family, and there was significant evidence of genetic heterogeneity. These results show that a gene for autosomal dominant HPE is located in a chromosomal region (7q36) known to be involved in sporadic HPE with visible cytogenetic deletions. They also demonstrate genetic heterogeneity in familial HPE. We hypothesize that mutations of a gene in 7q36, designated HPE3, are responsible for both sporadic HPE and a majority of families with autosomal dominant HPE.

Smith-Lemli-Opitz syndrome (SLOS) is an autosomal recessive disorder characterized by a defect in cholesterol biosynthesis, associated with mental retardation and multisystem structural abnormalities. This study investigated the prevalence of congenital CNS abnormalities by MRI in a large series of patients with SLOS and the correlation of the clinical and biochemical findings with the results of MRI and 1H MRS. Eighteen patients were studied; all underwent MRI of the brain, and 16 had 1H MRS of the cerebral white matter. The ratios choline:NAA, lipid:NAA, and lipid:choline metabolite were found to be correlated with the clinical degree of disease severity, serum total sterol ratios (cholesterol/cholesterol + 7-dehydrocholesterol + 8-dehydrocholesterol) and in two cases with the effect of cholesterol therapy. Abnormal CNS findings were noted in five patients, including callosal abnormalities (n = 4), Dandy-Walker variant (n = 1), and arachnoid cyst (n = 1). Holoprosencephaly was noted in one patient with a prevalence of 6%. Choline:NAA was elevated in seven patients. There was a statistically significant positive correlation between the lipid:choline ratio and the serum cholesterol precursor, 8-dehydrocholesterol. In two patients 1H MRS demonstrated abnormally elevated lipids prior to cholesterol therapy, which improved on therapy. The use of MRI and 1H MRS is an effective way to demonstrate brain structural abnormalities in patients with SLOS and may prove to be an effective method for the assessment of the effects of cholesterol replacement therapy in the brain.

SUMMARY The clinical phenotype in Lesch‐Nyhan disease has been analyzed in 19 patients studied in hospital. In each case the diagnosis was made on the basis of inactivity of the enzyme hypoxanthine guanine phosphoribosyltransferase in erythrocyte lysates. All had RÉSUMÉ La maladie de Lesch‐Nyhan: revue d'une expérience clinique chez 19 sujets ZUSAMMENFASSUNG Lesch‐Nyhan Syndrom: eine Zusammenfassung der klinischen Erfahrungen mit 19 Patienten An 19 Patienten, die im Krankenhaus behandelt wurden, wurde der klinische Phänotyp des Lesch‐Nyhan Syndroms analysiert. Die Diagnose wurde in jedem Fall durch den Inaktivitätsnachweis des Enzyms Hypoxanthinguaninphosphoribosyltransferase im Erythrocytenlysat gestellt. Alle Patienten hatten eine Hyperuricaemie und bei den meisten Fällen wurde als erster Hinweis der ‘orangefarbene Sand’ in der Windel angegeben. Alle hatten ein selbstzerstörerisches Verhalten, das charakteristischste war das Kauen an Fingernägeln und Lippen. Neurologisch wurde bei allen eine Spastik und unwillkürliche choreoathetoide Bewegungen gefunden. Alle mit einer Ausnahme hatten einen erniedrigten Intelligenzquotienten. RESUMEN Enfermedad de Lesch‐Nyhan: revision y experiencia clinica con 19 pacientes Se analizó el fenotipo clinico en la enfermedad de Lesch‐Nyhan en 19 pacientes hospitalizados. En cada caso el diagnóstico se hizo basándose en la inactividad del enzima hipoxantina guanina fosforibosiltransferasa en eritrocitos lisados. Todos tenian hiperuricemia y la presencia de ‘arena naranja’ en el pañal fue una observación prominente precoz. Todos tenian un comportamiento automutilante, siendo la forma más caracteristica el morderse los dedos o los labios. Todos tenian el sindrome neurológico de espasticidad y movimientos involuntarios coreoatetósicos. Todos, excepto un caso, tenian una inteligencia por debajo de la normal.

No abstract

Two infants are described with congenital cutis laxa. They represent two distinct disorders. In the first, congenital cutis laxa is associated with a generalized disorder of elastic tissue in which there may be diaphragmatic or other hernias, diverticula of the gastrointestinal or urinary tract and infantile emphysema. The disease is fatal often within the first year. In the second, congenital cutis laxa is associated with widely patent anterior fontanel, a variety of malformations, and retarded growth and development. Recognition of these distinct syndromes in the newborn period and their recessive inheritance permit realistic discussion of the prognosis which is very different from the benign dominant forms of cutis laxa.