ARG1 and asthma: The authors found a significantassociation of the rs2781659*G allele of the ARG1 gene witha more pronounced bronchodilatation response, and the ARG1gene was proposed as a possible risk marker to determinethe effectiveness of asthma therapy (Litonjua et al., 2008).Vonk et al. (2010) found a significant decrease of bronchodilatationresponse to beta-2-agonists in asthma patients fromNetherlands with the rs2781667*TT genotype of the ARG1gene.