Pharmacogenomics of Acute Asthma: The β2-Adrenergic Receptor Gene as a Model for Future Therapy

Asthma is a complex heterozygous multifactorial condition with variability in clinical features and response to treatment, likely related to interactions between genetics and environmental exposures. Pharmacogenomic research seeks to identify and elucidate relationships between genetic variation and therapeutic response. Multiple studies have examined genetic variation in the β2-adrenergic receptor gene and association with asthma phenotypes. Results suggest that single-nucleotide polymorphisms in this gene are associated with greater bronchodilation acutely after albuterol, worse pulmonary function over time with daily albuterol use, and tachyphylaxis to albuterol with chronic use. Although these results are intriguing, there are limitations of individual studies and discrepancies among their results that currently preclude broad conclusions and widespread application of genetic testing to guide therapy. This review will discuss these studies and the role that asthma pharmacogenomic research may play in the development of tailored acute asthma treatment regimens.