Interleukin-1b gene polymorphism and its association with chronic periodontitis in South Indian population

Abstract

Interleukin-1 beta (IL-1b) is a potent inflammatory mediator and an important polymorphism in the locus +3954 (C/T) of the human IL1B gene has been shown to affect the levels of this cytokine. This functional polymorphism has been associated with the establishment of inflammatory diseases, including periodontal disease, in European, Asian and North American populations. The aim of this study was to investigate the association between the IL1B (+3954) gene polymorphism and the occurrence of different clinical forms of periodontitis in South Indian population. This study employed a cross-sectional design involving individuals from the State of Tamil Nadu in the Southern region of India. Genomic DNA was obtained from 5 ml of venous blood and amplified using the polymerase chain reaction (PCR) with specific primers flanking the locus +3954 of IL1B. PCR products were submitted to restriction endonuclease digestion and analyzed by polyacrylamide gel electrophoresis, to distinguish alleles T and C of the IL1B gene, allowing for the determination of the genotypes and detection of the polymorphism. The chronic periodontitis group displayed a higher percentage of the T allele (28%) than C allele (8.7%). Our data suggested that the polymorphism in the locus +3954 of IL1B gene could be a risk factor for chronic periodontitis in South Indian population. Key words: Gene polymorphism, interleukin 1 beta, periodontitis, allele.