ADRB2 polymorphisms and asthma susceptibility: transmission disequilibrium test and meta-analysis.

Background: The beta(2)-adrenergic receptor (ADRB2) is the most common adrenergic receptor in the lung, and associations between ADRB2 polymorphisms and intermediate phenotypes of asthma have been reported. Four missense polymorphisms (Arg16Gly, Gln27Glu, Val34Met, and Thr164Ile) and one polymorphism in the 5' leader cistron of the ADRB2 messenger RNA has been identified. In vitro studies have shown that these missense polymorphisms can affect ADRB2 function.