Abstract
Periodontitis is a complex multifactorial inflammatory disease, and its genetic basis has been studied. The Interleukin-1 beta (IL-1β) is a crucial proinflammatory mediator in the pathogenesis of periodontitis with high polymorphism. This study aimed to investigate whether the rs1143634 genetic variant of the IL-1β gene is associated with an increased risk for periodontitis. For this purpose, genotyping of the IL-1β rs1143634 polymorphism was performed using the polymerase chain reaction-restriction fragment length polymorphism method on 90 patients within the age range of 35-60 years old. They were divided into two groups: 64 periodontitis cases (stage 3 and 4 periodontitis according to 2017 classification) and 26 racially matched healthy cases as the control group. Fisher's exact test showed a significant decrease in TT homozygous genotype in periodontitis cases, compared to the control group (P=0.018), suggesting that this genotype is a protective factor in the test population. Allele frequency showed an elevated odd ratio (1.24) and increased risk for periodontitis in subjects with allele C and reduced odd ratio (0.81) and reduced risk for periodontitis in subjects with allele T. Allele T of IL-1β rs1143634 polymorphism could be a protective factor, while Allele C of this polymorphism could be a risk factor for periodontitis in the studied Iraqi population.