The association and correlation of genetic polymorphism of the Interleukin-1β (+3954) gene and its respective cytokine IL-1β in saliva with periodontal disease in Pakistani population.

Objectives: Interleukin-1β is an inflammatory mediator and polymorphism at locus +3954 has effects on the production of inflammatory cytokines resulting in the development of periodontal diseases that has been proved in different populations, while its association in Pakistani Population was un discovered. The aim of this study was to assess the association of Interleukin-1β (+3954) gene polymorphism and to analyze the levels of salivary Pro Inflammatory Cytokine IL-1β with chronic periodontitis in a Pakistani population.
Methods: This case control study was conducted in Dow University of Health Sciences, Karachi, Pakistan. After clinical examination and consent, blood and saliva was collected as per protocol. Genomic DNA extracted from the blood was amplified using conventional PCR with specific primer flanking the locus +3954 of IL-1β. Sanger sequencing of PCR products in order to check the polymorphism was carried out, results were investigated with MEGA 7 software. Electropherograms were visually inspected to check the polymorphism and genotype were investigated using the reference sequence. Salivary cytokine levels of IL-1β were analyzed with enzyme-linked immunosorbent assay (ELISA). SPSS 17 was used for Data analysis P-values < 0.05 was considered as significant.
Results:
There were statistically significant differences between Cases and Controls regarding clinical parameters (p < 0.05). A significant difference was also observed in the allelic frequencies between the two groups, showing high prevalence of C allele in healthy individuals and T alleles were significantly higher in Patients (Pearson X²= 18.68, P= <0.001). Homozygous genotype CC was found significantly higher in Healthy Individuals and TT genotype revealed a significant association with the diseased (Pearson X²= 19.83, P< 0.001).
Higher levels of salivary cytokine IL-1β was observed in patients as compared to the healthy individual and significant correlation have been observed with single nucleotide polymorphism of IL-Iβ +3954 and salivary cytokine levels.
Conclusions: SNP of IL-Iβ +3954 could be a risk factor of chronic periodontitis in Pakistani population. Significant differences in the salivary cytokine levels can be used as a biomarker for periodontitis.