FAMILIAL RESEMBLANCE FOR IMMUNOGLOBULIN LEVELS

The familial resemblance for immunoglobulin A, D, E, G, and M levels w as investigated with family data collected in Canada and the U.S., ent ertaining bath 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 l evels. Whereas there have been several reports suggesting a major gene determinant for IgE levels, including that from our own Canadian stud y, analysis of the U.S. sample suggested that a multifactorial compone nt parsimoniously explained the observed familial resemblance.