The polymorphisms of ADRB2 gene might be related to asthma, mainly dueto being associated with increased airway sensitivity.8 Bronchial hyper-responsiveness is one of the main characteristics of asthmaand may be triggered by several factors, including exercise.29 The study carried out by Fukui et al.30 showed that individuals with increased responsiveness tomethacholine challenge test had a polymorphism at codon 16. This evidence concerns the gene ADRB2 and asthma.