BIOLOGY AND GENETICS OF ATOPIC DISEASE

Several immunological disorders including allergic rhinitis, bronchial asthma, atopic dermatitis, food allergies, urticaria, nonhereditary a ngioedema, systemic anaphylaxis, and allergic conjunctivitis are assoc iated with a positive family history, and share a positive response in the Prausnitz-Kuster (wheal and flare) reaction. Studies have shown t hat 20-30% of the population has a strong genetic predisposition for t his condition, termed atopy, whose hallmark is a greatly elevated seru m IgE concentration. A great deal is known about the cellular interact ions that mediate the sensitization, immediate and fate-phase reaction s that follow encounters with allergen, as well as about the cell surf ace and signaling events that result in mediator release from inflamma tory cells. Less is known of the genes that confer genetic predisposit ion for atopy; however, a worldwide effort to identify atopy genes is making significant progress.