ABSTRACT
The childhood-onset spinal muscular atrophies (SMAs) describe a heterogeneous group of disorders that selectively affect the alpha motoneuron. We have shown that chronic childhood-onset SMA (SMA II and III) maps to a single locus on chromosome 5q. Acute SMA (SMA Type I/Werdnig-Hoffmann/severe/infantile) is the main cause of heritable infant mortality. Mapping the acute SMA locus by conventional methods is complicated by the rapidly fatal course of the disease and its recessive mode of inheritance. We present here the typing of four inbred acute-SMA families with DNA markers on chromosome 5q and analysis of these together with acute families from our previous study to demonstrate genetic homogeneity between the acute and chronic forms of SMA. The data indicate that the acute SMA locus maps to chromosome 5q11.2-13.3. Two families seem unlinked to 5q markers, raising the possibility of genetic heterogeneity or disease misclassification within the acute and chronic family sets.
Subject(s)
Muscular Atrophy, Spinal/genetics , Spinal Muscular Atrophies of Childhood/genetics , Acute Disease , Chromosome Mapping , Chromosomes, Human, Pair 5 , Chronic Disease , Genetic Linkage , Humans , Pedigree , Polymorphism, Restriction Fragment LengthABSTRACT
Between April 1980 and March 1986, 19 infants underwent cerebrospinal fluid (CSF) shunting procedures for post-haemorrhagic ventricular dilatation at the Hammersmith Hospital, London. A total of 58 shunt-related procedures have been performed on these children. The major perioperative complication was seizure activity (eight children). Postoperative complications included infection (12 shunts) and blockage (29 shunts). Prophylactic antibiotics failed to prevent shunt infection. The likelihood of the first shunt failing was significantly reduced by greater weight of the infant and lower CSF protein at surgery. Long-term outcome was poor: three have died and another four are quadriplegic with severe mental retardation. Only four children are developmentally normal. These outcomes cannot be related to the shunt surgery or its complications, but correlate best with pre-operative parenchymal brain-lesions, as shown on ultrasound scans.
Subject(s)
Cerebral Hemorrhage/surgery , Cerebrospinal Fluid Shunts , Hydrocephalus/surgery , Infant, Premature, Diseases/surgery , Postoperative Complications/etiology , Child Development , Follow-Up Studies , Heart Atria , Humans , Infant , Infant, Newborn , Peritoneum , ReoperationABSTRACT
Hair samples were analyzed for mercury in 942 persons living in either one of two coastal areas of the United Kingdom who reported above average fish consumption. A duplicate diet study group was selected from the 942 individual's who had elevated concentrations of mercury in their hair. The study group's fish consumption averaged 0.36 kg/person . wk during the duplicate diet. Concentration of total mercury in the blood of the study group ranged from 1.1 to 42.3 micrograms/L with an arithmetic mean of 8.8 micrograms/L. The linear curve fitted to the data on the concentration of total mercury in blood vs. mercury intake was similar to that observed in a previous study made in the United Kingdom, but different from that observed in other studies. The results from the present study indicate that people in the United Kingdom are unlikely to be adversely affected by the presence of methylmercury in the fish they consume.
