ALOX5 promoter genotype and response to montelukast in moderate persistent asthma

Summary Background It was hypothesized that asthmatic patients with mutant alleles in the leukotriene pathway should not respond to leukotriene receptor antagonists and the concept of a tailored treatment is increasingly supported. Methods Sixty-one patients (mean age 24.9 years, range 14–52) with moderate persistent asthma were clinical and immunological assess prior and after a 6-month treatment with montelukast. Tandem repeat polymorphisms were genotyped in the promoter (−147 to −176) of 5-lipoxygenase gene (ALOX5). Results Thirty-two patients (52.5%) were homozygous for the five repeats allele; 17 (27.9%) were heterozygous (4/5 repeats) and 12 (19.7%) were homozygous for 4/4 repeats. After the montelukast treatment decrease number of asthma exacerbations, improvement of FEV 1 and decreased use of β 2 agonists was observed in patients with 5/5 or 4/5 repeats. Conversely, the patients with 4/4 repeats genotype did not modify these data after treatment. Conclusions It was confirmed that ALOX5 promoter polymorphisms have a clear influence in montelukast response in atopic moderate persistent asthma patients. The genetic study could identify those patients most likely to respond to montelukast.