Identification of the Interleukin-6 Polymorphism (-174) in the Saliva of Hemodialysis Patients

Background: Chronic Kidney Disease is prevalent in the general population and is associated  with high morbidity and mortality and its pathogenic mechanisms are related to pro-inflammatory cytokines, such as Interleukin 6 (IL-6). It is known that polymorphisms associated with IL-6 can trigger a different immune response in the individual and therefore be a determining factor in the progression of the disease. The idea of using saliva as an analysis matrix for diagnostic methods suggests that the methodology may be viable due to the easy way collection of these fluids and the amount of information in saliva molecular constituents. Aims: To identify the relationship between IL-6 polymorphism (-174) in dialysis patients using saliva. Methodology: 53 individuals were assessed, divided into a test group: 27 on hemodialysis; and a control group: 26 healthy individuals. Saliva samples were collected, DNA was extracted, and genotyping was performed using Real Time-Polymerase Chain Reaction (RT-PCR). For statistical analysis, the c2 was performed on categorical data. Results: The genotype frequency identified was 33.33% GC, 59.25% GG and 7.42% CC for the hemodialysis group and 19.23% GC, 50% GG and 30.77% CC for the healthy group(p=0.0806). Conclusion: It was possible to verify the presence of the IL-6 (-174) polymorphism in saliva. Nonetheless, the predominance of GG was not significant, corroborating with other studies, that also indicate no relation between IL-6 Polymorphism and CKD. In this study, it was not possible to correlate hemodialysis patients with the polymorphism studied, but more studies about this subject are necessary, mainly in countries with diverse population, as Brazil.