OBJECTIVETo determine whether genetic polymorphisms of beta2-adrenergic receptor gene affect asthma susceptibility and play a role in disease regulation.

METHODSOne hundred and sixty-six unrelated childhood asthma cases and 32 families with 192 samples were studied. The polymorphisms at amino acid positions 16, 27, 164 and nucleic acid residue 523 were genotyped by polymerase chain reaction-restriction endonuclease digestion.

RESULTSThe amino acid 164 Thr/Ile variant was seen only in the heterozygote form, and it occurred with a frequency of 3% which is similar to the published results among Caucasians. There were significant differences in the allele frequencies of the other 3 polymorphisms between Chinese and the published results among Caucasians (P<0.001). No polymorphism was found to be associated with total serum IgE, the number of positive prick skin test and FEV1. No significant association was noted between either the arginine-glycine 16 or the glutamine-glutamate 27 polymorphisms and the airway responsiveness to beta2-agonists in childhood asthma cases.

CONCLUSIONIn this study population, the authors were unable to confirm that the polymorphism of beta2-adrenergic receptor gene is a crucial factor of the susceptibility to asthma and a major genetic determinant of different clinical status.