目的　为了探讨哮喘患者β2 肾上腺素能受体 (β2 AR)与哮喘的关系。方法　应用聚合酶链反应 (PCR)法 ,检测了 6 0例汉族哮喘患者和 6 0例正常汉族人β2 AR基因 5′端 2 34 bp片段。结果　无论是哮喘患者还是正常人均存在着β2 AR基因 5′端 2 34 bp的扩增片段。结论　哮喘的严重程度与β2 AR基因的缺失无关 ,哮喘患者对β2 AR激动剂反应性不佳也非β2 AR基因缺失所致。 Objective To investigate the relationship between β2 adrenergic receptor (β2 AR) and asthma in asthmatic patients. Methods Polymerase chain reaction (PCR) was used to detect the 2 34 bp fragment of 5’-end of β2 AR gene in 60 Han Chinese patients and 60 normal Hans. Results The 2 34 bp 5’-end amplified fragment of β2 AR gene existed in both asthmatic and normal subjects. Conclusion The severity of asthma is not related to the loss of β2 AR gene. The asthmatic patients are not responsive to β2 AR agonists and are also caused by the absence of β2 AR gene.