Background: Allergy is regarded as a multifactorial condition that its onset and severity are influenced by both genetic and environmental factors. Hence, identification of genetic factors involved in allergic rhinitis development and its related phenotypes is a major task in understanding the genetic background of allergic rhinitis. This study was designed to examine the association between IL-18 -607 A/C promoter polymorphism on chromosome 11q22 and allergic rhinitis.

Materials and Methods: In this analytic study, genomic DNA was obtained from the blood samples of 293 patients with allergic rhinitis and 218 healthy controls by standard phenol chloroform method. The IL-18/-607 A/C polymorphism was analyzed by polymerase chain reaction and restriction fragment length polymorphism (PCR-RFLP) analysis. To analyze the association between genotypes and alleles and the disease in the case group compared with the control group, X2 test was used.

Results: The frequency of the AC genotype of the IL-18/-607 A/C gene polymorphism was significantly greater in allergic rhinitis patients than in controls (p<0.05). By comparing the frequency of AA genotype with other genotypes, OR was calculated as 2.03.

Conclusion: The results suggest that IL-18/-607 A/C polymorphism gene may be one of the factors participating in the pathogenesis of AR or its intermediary phenotypes.