ALOX5 and asthma: In a six-month clinical trial of montelukast therapy in patients with asthma, in which 80% of European Caucasians and 47% of African Americans, carried five tandem repeats of the ALOX5 promoter sp1 tandem repeat polymorphism, European Caucasian participants carrying a variant number (either 2, 3, 4, 6, or 7) repeats of the ALOX5 promoter on one allele had a 73% reduction in the risk of having one or more asthma exacerbations compared with homozygotes for the five repeat alleles [115].