Arg16gly polymorphism of the beta2-adrenoceptor gene (ADRBeta2) as a susceptibility factor for nasal polyposis

Background: Nasal polyposis is probably a multifactorial disease, but so far, no genetic susceptibility factor has been identified. The observed associations between the ADRB2 arg16gly polymorphism and asthma-related phenotypes as well as those between nasal polyposis and asthma have prompted us to evaluate the potential involvement of this polymorphism in sinonasal polyposis. Methods: We enrolled in our study, 56 patients and 47 sex- and age-matched controls. Genomic DNA from cases and controls was extracted and genotype was assessed by a polymerase chain reaction amplification/Nco I digestion assay. Statistical analysis was performed using JMP software (version 5.1). Results: The "number of arg alleles" is significantly higher in cases than in controls (p = 0.0386 at t-test; substantially confirmed by nonparametric tests, p = 0.0396 by Wilcoxon/Kruskal-Wallis tests). Conclusion: Although results of this study are preliminary because of the small size of the sample, the arg16 allele seems to be associated with an increased risk of sinonasal polyposis suggesting ADRB2 as a susceptibility gene. This finding, if confirmed, would have a clinical value in helping to assess the genetic risk for sinonasal polyposis thus opening new perspectives for the study of molecular factors underlying the development of nasal polyps.