Genetic analyses of pyloric stenosis suggesting a specific maternal effect.

Data on pyloric stenosis are analysed by multiple threshold methods that incorporate the sex effect. The polygenic model of inheritance is rejected; the single major locus model can only account for 37% of the cases having a genetic aetiology, requiring an environmental effect to account for the remainder of the cases. A maternal-fetal interaction for gastrin production and sensitivity is postulated to explain all the existing data.

Inborn errors of metabolism in the Maritimes, with special reference to maple-syrup-urine disease and Fabry's disease.

1. The study of inborn errors of metabolism in man is of wide, general relevance to human biology and medicine, because these derangements are unique human models for the study of the sequence of normal metabolic events and their dependence upon genetic control. These disorders constitute naturally occurring mutations in man; as such, they afford the same opportunity for major contributions to human biology that bacterial mutants provide for molecular biology.

Extensions to pedigree analysis. III. Variance components by the scoring method.

The classic variance components for simple polygenic traits - additive, dominance, and environmental variance - have traditionally been estimated from sample covariances between first-degree relatives. If data is gathered on pedigrees, this statistical procedure wastes information. Recently Elston & Stewart suggested an alternative likelihood procedure that uses all the information in a set of pedigrees.

Application of the lod method to the detection of linkage between a quantitative trait and a qualitative marker: a simulation experiment.

Simulation experiments were performed to assess the power of the lod method for detecting linkage between a quantitative trait and a qualitative marker. Using family data on the Amy2-Duffy linkage, it was found that linkage detection is feasible in certain limited circumstances. The same qualitative data yielded no evidence for a significant difference in male and female recombination fractions.

Mesoridazine and human sleep.

1 Mesoridazine, a phenothiazine of short half-life, and potentially useful as an hypnotic, has here been investigated using volunteers of late middle age. 2 The electrophsiological recording of all-night sleep was studied in seven subjects for a 7-week period during which ther received mesoridazine (10 mg nightly) for 3 weeks. The drug reduced the frequency of transitions into wakefulness and stage 1 (drowsiness) and reduced the time spent in stage 1; there was a withdrawal rebound.

Failure to correct the metabolic defect by renal allotransplantion in Fabry's disease.

Plasma neutral glycolipid levels and plasma and leukocyte alpha-galactosidase activities were measured serially before and after renal allotransplantation in two men, aged 47 and 45 years, with renal failure due to Fabry's disease. The patients were followed posttransplantation for 92 and 64 weeks, respectively. No significant elevation of plasma or leukocyte alpha-galactosidase activities above levels in untreated men with Fabry's disease or decrease in the levels of trihexosyl ceramide was observed in either patient.

Estimation of polygenic recurrence risk for cleft lip and palate.

Data on cleft lip with or without cleft palate are utilized to evaluate a new method for estimating recurrence risk under the polygenic threshold model. The influence of critical factors on the accuracy of the estimated risks are evaluated. The model is relatively sensitive to the estimate of heritability employed and relatively robust to the population prevalence estimate and to family size.

Does anaemia increase the risks to the fetus caused by smoking in pregnancy?

A significantly greater rise in carboxyhaemoglobin concentration in response to smoking a single cigarette was shown in pregnant (3-9% increase) as opposed to non-pregnant (2-1% increase) women. This was more pronounced when anaemia was present (5-0% increase) and appeared to be inversely related to the haemoglobin concentration. We suggest that the risks to the fetus may be particularly increased when anaemia complicates pregnancy in women who smoke cigarettes.

Arrhythmias in the coronary-care unit. I. Physiologic bases of ectopic beats.

Ectopic beats appearing in the wake of an acute myocardial infarction are best explained with a fundamental knowledge of myocardial cellular electrophysiology. When the physician or nurse has knowledge of the electrical events of intracellular recordings then normal as well as abnormal states of automaticity and conductivity are better understood.

Mitotic association patterns of nucleolar organizing chromosomes in the mouse.

Following the report of localization of nucleolar organizer regions to chromosome pairs 15, 18, and 19 of the mouse, a study was undertaken to test these chromosomes for association during mitotic metaphase. Cells from sevel strains of mice were analyzed, and no strong evidence was found for any significant association patterns.