Does IL-18 Promoter Gene Polymorphisms Increase Risk of Multiple Sclerosis

Multiple sclerosis (MS) is an inflammatory and degenerative disease of the central myelin, which can lead to a significant disability. The aim of this study was to investigate IL-18 gene polymorphisms in multiple sclerosis patients referring to Shahrekord health centers. Materials and Methods: This case-control study was carried out on 57 relapsing remitting multiple sclerosis (RRMS) patients and 57 healthy individuals as control group in Shahrekord university of medical sciences. Blood samples were collected and DNA was extractedby salting out method. The alleles of each of the IL-18 genes polymorphisms were determined using a specific two-stage allele polymerase chain reaction. All PCR reactions were carried out in a mix volume of 25 μl. PCR was performed for rs187238 and rs1946518 andthe PCR products were analyzed on 2% agarose gel stained with ethidium bromide. Collected data were analyzed by SPSS software. Results: Among the studied patients, 69.3% were female and 30.7% were male. The frequency of GG, CC, and GC genotypes for IL-18- 137 gene was 61.4%, 12.3% and 26.3%, respectively, in MS patients versus 54.4%, 8.8% and 36.8% in the control group (P> 0.05). Frequency of AA, AC and CCgenotypes for IL-18-607 gene was 21.1%, 38.6% and 40.4% in patients with MS and 17.5%, 38.6% and 43.9% in the control group (P> 0.05). All possible genotypes were detected in the control group, while CC / CC and GC / CC genotypes were not observed in patients withMS. There was no significant difference in the frequency of combined genotypes between patients with MS and control group (P> 0.05). Conclusion: There was no significant difference in distribution of genotypes and alleles of IL18-137 and IL18-607 genes as well as theircombined genotypes. Also, similar studies on different ethnic populations can help to clarify the association between IL-18 polymorphisms and MS disease.