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Serum-immunoglobulin levels (IgG, IgM, IgA, IgD and IgE) have been studied in white and metis (Cree Indian) communities in Saskatchewan. The levels of IgG, IgA, IgD and IgE were higher in the metis than in the whites. Both IgG and IgM were higher in females than in males. IgG and IgA levels rose progressively with age. IgM levels rose rapidly during the first year to almost adult levels, and then fell gradually alter the age of 30. IgE levels also rose rapidly during the first 3 years of life, were higher on average in children than in adults, and fell to adult levels at puberty. Low levels of IgA were associated with high levels of IgG; they were not associated with tither high levels of IgE or an increase in the prevalence of asthma. [ABSTRACT FROM AUTHOR]

The familial resemblance for immunoglobulin A, D, E, G, and M levels was investigated with family data collected in Canada and the U.S., entertaining both multifactorial and single gene hypotheses. Significant familial effects were found for each of the immunoglobulins, and there was significant support for a major gene hypothesis for IgA and IgD levels. Whereas there have been several reports suggesting a major gene determinant for IgE levels, including that from our own Canadian study, analysis of the U.S. sample suggested that a multifactorial component parsimoniously explained the observed familial resemblance.

Levels of serum IgD have been measured in white and Metis (Cree Indian) communities in Saskatchewan. IgD levels in the Metis were, on average, 10 times as high as those in the white population. In both groups IgD levels rose rapidly to reach, by the age of two years, levels which did not differ significantly from those found in the adult. From the age of two to three years, levels in the populations remained relatively constant with time, although levels in any of individual may rise or fall over a three-year period by factors ranging from 10 to 20.

This study was carried out to determine whether respiratory disease in Saskatchewan grainhandlers was or was not due to hypersensitivity to grain dust. Sixty nonsmoking grainhandlers, half of whom had low FEV1/FVC ratios and half of whom had high, were studied. The findings in grainhandlers were compared with those in 30 age-matched, nonsmoking teachers. In the group of grainhandlers with low FEV1/FVC ratios, one had developed asthma associated with exposure to grain dust. The majority were healthy, had FEV1/FVC ratios of 70% or greater, and had less evidence of allergic respiratory disease than had age-matched teachers. The studies suggest that non-atopic, nonsmoking men can work in grain elevators without developing respiratory disability, though they may develop a small but significant increase in nonspecific bronchial reactivity to histamine.

Serum IgE levels have been measured over two to three years in 210 individuals. In one-fifth IgE levels remained remarkably constant, in one-quarter they rose and in half they fell. A rise was usually associated with the development of fresh atopic disease, exacerbation of established disease or dependence on symptomatic treatment. A fall was associated with a diminution in the severity of symptoms occurring spontaneously as a result of good environmental control or of appropriate immunotherapy. Sequential IgE levels provide confirmatory evidence of the success of either environmental control or of immunotherapy.

A service has been developed in Saskatchewan to make available the results of studies of human chromosomes, the material being forwarded to the laboratory by local transport facilities. During the first year of this project chromosome studies were requested for five doubtful cases of trisomy-21 (two were found to be normal) and for 20 definite cases of trisomy-21 in young patients (two had translocations but the parents of both these children had normal karyotypes). Eleven confirmed cases of Turner's syndrome, two of Klinefelter's syndrome, and one each of the D and E syndromes were also studied. The largest group for which studies were requested comprised 36 patients with mental retardation; only two abnormal karyotypes were encountered in this group.