Inverted tandem duplication generates a duplication deficiency of chromosome 8p.

An adult female with sever mental retardation and dysmorphic features is described. A de novo chromosomal aberration involving 8p was found. The karyotype was 46, XX, inv dup (8) (p12----p23.1). Dosage studies with the DNA probe D8S7, which is located at 8p23----8pter, showed that the patient was monosomic for this marker. Thus the de novo rearrangement generated a duplication-deficiency chromosome. The possible mechanisms of formation of this abnormal chromosome are discussed.

Infantile autism: an occasional manifestation of fragile (X) mental retardation.

Classical infantile autism occurs more frequently in males and has recently been noted in patients with the fragile (X) form of X-linked mental retardation (XLMR). In order to better understand this association and to determine whether fra(X) XLMR could account for the excess of autistic males, we investigated a group of institutionalized severely handicapped adults, 33 males and eight females, who were diagnosed as autistic using the DSM III diagnostic criteria of infantile autism. Chromosome studies using FUdR showed that three of the males had the Xq27 fragile site. We confirmed the association of autism and fra(X) XLMR, and showed that this extreme form of behaviour is part of the spectrum seen in the Martin-Bell syndrome. Two of the three autistic males with the Xq27 fragile site had a history of birth insults, which in combination with developmental deficits due to the fragile X gene, might have led to the behavioural disorder. Even though the fragile X cannot account for the excess of males with classical autism, it is an important X-linked factor in its cause. The diagnosis can allow more accurate counselling for this subset of autistic males.

Survival and spectrum of anomalies in the Meckel syndrome.

We present two sisters whose malformations (hydrocephalus, cystic dysplasia of the kidneys, polydactyly, and cleft palate) are consistent with a diagnosis of the Meckel syndrome. Diagnosis in case 1 was delayed because of two factors: 1) prolonged survival (28 mo), and 2) the absence of severe craniofacial malformations. These two factors may create difficulties in making this diagnosis and result in uncertainty regarding the medical prognosis of the infant and the genetic prognosis for the parents.

Krabbe's leukodystrophy without globoid cells.

Krabbe's infantile cerebral sclerosis with a prolonged course was present in a boy who became increasingly hypertonic during infancy and had an increased protein level in the spinal fluid. At 4 years he showed significant growth failure, profound mental retardation, spastic quadriplegia, bilateral optic atrophy, and depressed tendon reflexes. Conduction velocity in motor fibers of the median nerve had become progressively impaired. Autopsy at 5 years 10 months showed severe leukodystrophy with demyelination and gliosis. No stored breakdown products or globoid cells were seen in the brain. Galactosyl ceramide beta-galactosidase was virtually absent, and hardly any myelin was demonstrable on chemical and electron microscopic studies. The presence of globoid cells may not be essential for the pathologic diagnosis of Krabbe's leukodystrophy in the presence of appropriate enzyme deficiency.

Incidence of phenylketonuria in British Columbia, 1950-1971.

The incidence of PKU in British Columbia in the 1950-1971 period is 1/18,750 which corresponds to that found in two other Canadian studies.(2, 3) Evidence is presented which shows a trend toward a decline in incidence; however, this is not statistically significant. There is a preponderance of male cases in all age groups.

Experience with pericyazine in profoundly and severely retarded children.

The effectiveness of pericyazine in severe behavioural disorders was evaluated in 15 profoundly and severely retarded children. Pericyazine provided significant improvement in such parameters as co-operation, temper, purposeless activities, hyperactivity, communication and mood. It proved to be statistically superior to the minor tranquillizers in improving co-operation and helpfulness, temper, mood, the understanding of commands and table manners, and in reducing self-abusiveness and abusiveness to staff. The safety of this agent was confirmed and photosensitivity was not found to be associated with its use.