Pharmacogenomics of -Agonists in Asthma

2) there is great controversy among clinicians as to the toxicity and appropriate 

A total of 13 polymorphisms in the gene and its transcriptional regulator beta-upstream peptide (BUP) have been identified [73]. Three closely linked polymorphisms, two coding block SNPs at amino acid positions 16 and 27, and a SNP in the BUP were found to be common (i.e., allele frequency 0.15) in the general Caucasian population [74, 75]. 

Although initial studies suggested a relationship between the Gly 16 polymorphism and increased risk of severe asthma [76] and increased airways responsiveness [77], subsequent associations with asthma, allergy and airways responsiveness have been inconsistent [74, 76-81]. 

The in vitro data and the results from this clinical trial were synthesized in a so-called dynamic model of receptor kinetics by Liggett [72]. According to this theory, Gly/Gly homozygous individuals are already down-regulated as a result of exposure to endogenous catecholamines. Thus, the recurring exogenous exposure to 

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