The immunopathology and genetics of asthma.

The definition of asthma and its related phenotypes is problematic because multiple factors are involved in its development. Asthma is thought to be a complex chronic inflammatory disorder of the airways resulting in symptoms of coughing, wheezing, and shortness of breath associated with evidence of bronchial reversibility and/or hyperreactivity. The ultimate clinical picture involves a variety of cellular and noncellular factors and multiple pathways, all of which are influenced by genetic and environmental factors. This article provides an overview of the characteristics and pathogenesis of asthma and atopy, as well as of genetic research underway to determine the major genes likely involved. These genes may interact with each other as well as with environmental variables that may influence the immune response.