The Epidemiology and Genetics of Atopic Allergy

STUDIES of atopic allergy (“ allergy ”) have provided new insight in defining the epidemiologic and genetic basis for the human immune response.^{1 , 2} Allergy is characterized by the development of antibody responses of a unique immunoglobulin — IgE³ — after exposure to inhaled, ingested, or injected antigens (usually termed “allergens ”). Under conditions of natural exposure to extremely low doses (usually less than 1 μg per year),⁴ atopic persons have IgE-antibody responses toward an array of environmental allergens present in pollens, fungal spores, animal danders, and similar substances. Synthesis of IgE is favored by natural immunization through inhalation, since antigens come directly into.  . .