Cytokine gene polymorphism (interleukin-1β +3954, Interleukin-6 [-597/-174] and tumor necrosis factor-α -308) in chronic periodontitis with and without type 2 diabetes mellitus.

BACKGROUND Pro-inflammatory cytokine gene polymorphisms are potential candidates for susceptibility for both type 2 diabetes mellitus (DM) and chronic periodontitis (CHP). This study explored the association of interleukin-1 beta (IL-1 β) +3954, interleukin-6 (IL-6) -597/-174 and tumor necrosis factor-alpha (TNF-α) -308 single nucleotide polymorphisms in CHP with and without type 2 DM in Malayalam speaking subjects of Dravidian ethnicity. MATERIALS AND METHODS This case control study consisted of 51 chronic periodontitis with type 2 diabetes mellitus (CHPDM) and 51 CHP patients as cases and 51 healthy subjects as controls. Polymorphisms were identified by polymerase chain reaction amplification followed by restriction enzyme digestion and gel electrophoresis. RESULTS IL-1 β (+3954) TT genotype and T allele were significantly associated with CHPDM group when compared with CHP (P = 0.001), whereas CC genotype and allele C was higher in CHP subjects (P = 0.001). For IL-6 (-597) frequency of genotype GA/AA (P = 0.04) and allele A (P = 0.01) was lower in CHPDM group, and for TNF-α -308 the frequency of genotype GA (P = 0.01) and allele A (P = 0.01) was higher in CHP subjects when compared with controls. CONCLUSIONS In Malayalam speaking Dravidian population, IL-6 (-597) genotype GA/AA and allele A appears to be protective for CHP with type 2 DM. Allele C of IL-1 β +3954 and allele A of TNF-α -308 appears to be risk factors for CHP individuals.