beta(2)-adrenergic receptor polymorphisms affect airway responsiveness to salbutamol in asthmatics

We examined the beta(2)-adrenergic receptor (beta(2)AR) polymorphisms (Arg1 6 --> Gly, Gln27 --> Glu) and clinical status for 117 asthmatics. Airway re sponsiveness to methacholine and beta(2)-agonists was evaluated with Astogr aph(R). The atopic factors, pulmonary function test, and airway responsiven ess to methacholine did not differ significantly among the different beta(2 )AR genotypes. Asthmatics homozygous for Gly16 showed significantly lower a irway responsiveness to inhaled salbutamol than those heterozygous for Arg/ Gly16 or homozygous for Arg16. Asthmatics heterozygous for Gln/Glu27 had si gnificantly later asthma onsets than those homozygous for Gln27. These resu lts suggest that beta(2)AR poly morphisms play an important role in the air way responsiveness to inhaled beta(2)-agonist and the initial asthma onset.