DOG ALLERGY, A MODEL FOR ALLERGY GENETICS

Experimental sensitization in dogs has revealed that the capacity to p roduce high levels of IgE against a variety of allergens (high IgE res ponders), an essential characteristic of the atopic state, is a geneti c trait inherited in a dominant manner. In high IgE responder dogs spo ntaneous development of IgE to inhaled allergens, such as house dust m ites, on the other hand, represents an apparent phenotype very similar to that observed in human atopic families. The full potential of the high IgE response gene appears to be fulfilled only under some conditi ons such as early and repeated exposition to allergens. It is therefor e quite possible that the true phenotype of human atopy would also be inherited in a dominant fashion but not constantly expressed. This wou ld explain why the increase in the prevalence of allergic diseases sta rted long before the environmental factors currently accused could hav e been at play. This hypothesis, which can be verified experimentally, has important implications for the future of allergy.