Inhaled corticosteroids are used by millions of asthma patients every day. However, as with all treatments to control asthma, there is marked patient-to-patient variability in the response to treatment. New research published today in the New England Journal of Medicine (NEJM) has identified a genetic variant associated with the response to inhaled corticosteroids [1]. Investigators have found that asthma patients who have two copies of a specific gene variant responded only one-third as well to steroid inhalers as those with two copies of the regular gene.