Study On The Relationship Between The Promoter SNP Of IL-18 And Type 2 Diabetes Mellitus In Han Population In Zhu Hai

Objective:In this study,we investigated single nucleotide polymorphism(SNPs) frequency distribution of interleukin 18(IL-18) gene for Type 2 diabetes mellitus(T2DM) patients and normal controls and identify the association of two SNP sites of IL-18 with T2DM of Han population in zhuhai.In the same time,we detected the level of serum IL-18 of patents and controls to observe the change of IL-18 level in T2DM,and investigated association of serum IL-18 and IL-18 gene SNP. Methods:SNP of IL-18 gene promoter at position-137C/G and-607C/A inl01patients with T2DM and105 normal controls were detected by using the technology of polymerase chain reaction-restriction fragment length polymorphism(PCR-RFLP).The frequency of allele and genotype were compared between patients and controls. Serum IL-18 level of the two group were detected by applying ELISA method. Results:1.The average serum IL-18 level of the case group (296.29±141.23pg/ml) is significantly higher than that of the control group (239.68±95.23 pg/ml).There was statistical difference between the two groups.2.The mutation at the position of-607C/A in the promoter of IL-18 gene had three genotypes:CC,AA,C/A.There was no statistical difference of the frequency of genotypes and alleles of-607C/A between the case group and the control group(P>0.05).3.The mutation at the site of-137G/C in the promoter of IL-18 gene had also three genotypes:GG,CC,G/C. There was statistical difference of the genotypes between the case group and the control group (χ2=9.809, P=0.011).The frequency of G allele in the case group was higher than the control group (χ2=7.261,P=0.007). The relative risk analysis of allele of developing T2DM indicated G allele was 2.33 times to the C allele (OR=2.33,95%CI=1.259-4.311).4. The serum IL-18 level of GG genotype of the-137site (307.37±143.05pg/ml) was higher than G/C+CC genotype (221.31±104.23pg/ml) in the case group and there was statistical difference between them.Conclusion:1.Compare with the control group, the serum IL-18 level was high in the case group.2. The site-137G/C of the promoter of IL-18 gene probably correlated with genetic predisposition of T2DM among the Han population in zhuhai of China. G allele was possible the one of risk factors of T2DM.3.The patients of T2DM had a high level of serum IL-18,and there was statistical difference of the serum IL-18 level between the-137GG genotype of the case group and the control group.The serum IL-18 level of-137 GG genotype was significantly higher than G/C+CC genotype in the case group.