the -137G/C Polymorphism in Interleukin-18 Gene Promoter Contributes to Chronic Myeloid Leukemia Risk in Turkish Patients

Interleukin-18 (IL-18) is a cytokine which belongs to the interleukin-1 superfamily and secreted by various immune and non-immune cells. Evidence has shown that IL-18 has both anticancer and procancer effects. The aim of this study was to evaluate the relationship between -137G/C (rs187238) IL-18 gene polymorphism and susceptibility to chronic myelogenous leukemia(CML) in Turkish patients. The frequencies of polymorphism -137G/C were studied in thirty chronic myelogenous and thirty healthy individuals. The genotyping was performed by polymerase chain reaction and DNA sequencing analysis. Significant associations were detected between the IL-18 rs187238 (G/C) polymorphism and CML patients. A higher prevalence of the C allele was found in CML cases with respect to controls (p<0.05). The GC heterozygote and CC homozygote genotypes are associated with the risk of CML when compared with controls (OR, 1.9023; 95% CI, 0.6171-5.8636 for GC genotype and OR, 10.3585; 95% CI, 0.5326-201.4622 for CC genotype). These results indicate that individuals that are either heterozygote (GC) or homozygote for CC genotype are associated with the development of chronic myelogenous leukemia in Turkish population. Further large-scale studies combined with haplotype and expression analysis are required to validate the current findings.