Unraveling the Genetic Basis of Asthma and Allergic Diseases

effects contributed to asthma development.3 The genetic factor may account for 40% to 60% of variance in allergen specific IgE level, 30% in log eosinophil count and 30% to 60% in positive skin test to dust mite in etiology.4 The remainder of atopy and asthma etiology is therefore attributable to environmental variables and partly interactive gene-environment influences.In past decades, great efforts have been exerted in unraveling the genetic basis of asthma and allergic diseases.This review is intended to briefly summarize what have been done and achieved in discovering, confirming genes and genetic variants and current consensus on genetics of asthma. DISCOVERING GENE AND GENETIC VARIANTS OF ASTHMA AND ALLERGIC DISEASESSeveral strategies have been applied to identify genes and genetic variants that predispose to asthma and allergic diseases.These mainly include positional cloning, candidate gene approach, genome wide association study as depicted in Fig. 1. Positional cloningPositional cloning is a popular approach used to identify genes Review