BACKGROUND AND OBJECTIVES: A recent study has demonstrated a possible involvement of leukotriene C4 synthase (LTC4S) gene polymorphism in ASA-intolerant asthma (AIA) in a Polish population, while no significances were noted in other populations. To investigate the role of genetic polymorphism in AIA development, we screened single nucleotide polymorphisms (SNPs) for the key enzymes involved in arachidonate metabolism, and cysteinyl leukotriene receptor 1 (CYSLTR1) in a larger scale of Korean population with AIA. MATERIALS AND METHODS: 93 AIA and 181 ASA-tolerant asthma (ATA) patients, and 123 normal controls (NC) were enrolled. Single base extension method was applied for genotyping of SNPs in 5-lipoxygenase (ALOX5, -1708G>A, 21C>T, 270G>A, 1728G>A), ALOX5 activating protein (FLAP, 218A>G), cyclooxygenase 2 (COX2, -162C>G, 10T>G, 228G>A), LTC4S (-444A>C), and CYSLTR1 (927T>C). Haplotype analyses for ALOX5 were performed as well. RESULTS: There were no significant differences in allele and genotype frequencies of the SNPs among the three groups (p>0.05). However, the frequency of ALOX5-ht1[G-C-G-A] containing genotype in the AIA group was significantly higher than those of the ATA group (p=0.01, OR =5.0, 95%CI=1.54-17.9) and the normal controls (p=0.03, OR=4.5, 95%CI=1.1-18.4) with a dominant model. CONCLUSION: These results suggest a lack of association between FLAP, COX2, LTC4S, and CYSLTR1 gene polymorphisms, and AIA phenotype in Korean population. However, a possible involvement of ALOX5-ht1[G-C-G-A] in AIA development was suggested.