Investigation of the Relationship between the Multidrug Resistance 1 Gene Polymorphisms and Bronchodilator Response in COPD

Abstract

Objective: Chronic obstructive pulmonary disease (COPD) is described as partially reversible airflow limitation. P-glycoprotein (P-gp/MDR1), encoded by the Multidrug Resistance 1 (MDR1) gene, is regarded as a protective component for the respiratory tract and is present in tracheobronchial epithelium and lung parenchyma, and removes particles from cells and protects against various xenobiotics. Polymorphisms of MDR1 gene and the alteration in the expression of P-gp are considered to have a negative effect on the severity of COPD pathogenesis and treatment efficacy. We aimed to investigate the relationship of the MDR1 gene polymorphisms with reversibility in COPD patients. Materials and Methods: The MDR1 polymorphisms, specifically the 3435C>T and 2677A/G variations, were analyzed in 90 COPD patients. Results: 15 of the 90 COPD patients had positive reversibility tests. 2677TT (p=0.044) and 3435TT (p=0.003) alleles related to positive reversibility tests. There were no significant differences in the distribution of the MDR1 C3435 alleles and the G2677 alleles (p> 0.05). Conclusion: COPD patients with the TT allele have a higher rate of early reversibility positivity; this suggests that those carrying the allele may respond better to bronchodilator therapy. These markers could help to distinguish COPD patients who respond better to ss2-agonists or who may not benefit much and, therefore, need different drugs.