Table of Contents
ISRN Pulmonology
Volume 2013 (2013), Article ID 280843, 6 pages
http://dx.doi.org/10.1155/2013/280843
Clinical Study

Polymorphism of Beta2-Adrenoceptor and Regular Use of Formoterol in Asthma: Preliminary Results

1Unità di Pneumologia, Università Cattolica S. Cuore, Largo A. Gemelli 8, 00168 Roma, Italy
2Department of Genetics, Catholic University, Largo A. Gemelli 8, 00168 Roma, Italy
3Department of Geriatrics, Campus Biomedico University, via Álvaro del Portillo 21, 00128 Roma, Italy

Received 20 February 2013; Accepted 11 March 2013

Academic Editors: Y. Dobashi and Y. Rojanasakul

Copyright © 2013 Leonello Fuso et al. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

Abstract

Polymorphism at codon 16 of the beta2-adrenoceptor (beta2-AR) affects the responsiveness to salmeterol in asthmatics. Data concerning formoterol are more controversial in the literature. The aim of this study was to verify whether homozygous for arginine-16 (ArgArg16) and homozygous for glycine-16 (GlyGly16) genotypes differently influence the long-term responsiveness to formoterol. Twenty-nine patients with mild-to-moderate asthma, in stable clinical conditions, underwent genotyping at codon 16 of the beta2-AR by RFLP-PCR assay. The effects of a 4-week monotherapy with formoterol (12 μg BID) were tested on the peak expiratory flow (PEF) variability and the forced expiratory volume in 1 sec (FEV1) slope of the dose-response curve to salbutamol. Variability in PEF significantly increased during the 4-week treatment period in 14 patients with GlyGly16, but not in 15 patients with ArgArg16 and ArgGly16 . The FEV1 slope of the dose-response curve to salbutamol decreased after the 4-week treatment period in GlyGly16, but not in pooled ArgArg16 and ArgGly16 patients. This study provides preliminary evidence that tolerance to formoterol develops more frequently in asthmatics with GlyGly16 genotype. If confirmed in a larger population, this finding might be useful in choosing the bronchodilator therapy on the basis of genetic polymorphism of the beta2-AR.