Interleukin-1 gene polymorphisms and periodontal status in a Spanish population

The aim of this study was to investigate the possible association between interleukin (IL)-1A (+4845) and/or IL-1B (+3954) gene polymorphisms and the onset and progression of chronic periodontal disease (PD), an issue that remains controversial. The relationship between IL-1β concentration in the gingival crevicular fluid (GCF) and disease activity was also evaluated. The study was performed on 25 individuals with no gingivitis or PD and on 25 subjects with active chronic PD. Two samples of GCF were obtained from each subject and IL-1β was determined by enzyme-linked immunoabsorbent assay. Blood samples (10 ml) were drawn from each subject to detect polymorphisms in IL-1A (+4845) and IL-1B (+3954) by polymerase chain reaction. Mean GCF IL-1β concentrations were higher in patients with active chronic PD compared to the control group. No significant association was found in either group between GCF IL-1β concentration and the presence of polymorphisms in IL-1A (+4845), IL-1B (+3954) or both genotypes. No significant difference was found in either group with regard to the presence of polymorphisms in IL-1A (+4845), IL-1B (+3954) or both genotypes (p=0.556). The concentration of IL-1β in GCF was almost 2-fold higher in patients with chronic PD than in the healthy individuals. The presence of polymorphisms in IL-1A (+4845) and/or IL-1B (+3954) genotypes is not associated with IL-1β overproduction in GCF and is not a risk factor for chronic PD. IL-1β is considered a suitable marker of the severity and progression of chronic PD. The presence of IL-1A (+4845) and/or IL-1B +3954 gene polymorphisms does not appear to be a risk factor for chronic PD. Therefore, the IL-1A (+4845) and/or IL-1B +3954 gene polymorphisms cannot be considered genetic markers of chronic PD. Moreover, these polymorphisms do not indicate an overproduction of IL-1β in GCF.