An explorative study on the interaction of cyclin-dependent kinase inhibitor 2B antisense RNA 1 (CDKN2B-AS1/ANRIL) gene polymorphism with obesity on periodontitis among Norwegian adults

Objective ANRIL is a pleiotropic gene with a strong link to periodontitis. ANRIL gene variant rs1537373 is associated with altered CDKN2B gene expression, which is linked to obesity. In this explorative, cross-sectional population-based study, we aimed to investigate the hypothesis that ANRIL (rs1537373) T>G may be associated with periodontitis through interactions, focusing on rs1537373×obesity interaction. Methods Genotyping for ANRIL (rs1537373), and clinical and periodontal examination were performed in 3554 participants (aged 40-93 years, 52% women) from the seventh survey of the Tromsø Study (2015-2016), Norway. We defined periodontitis stage based on radiographic bone loss (2018 AAP/EFP classification). Results The individual association between rs1537373 and periodontitis, as well as multiplicative and additive interactions between rs1537373 and age, sex, smoking, and obesity on periodontitis under a recessive model were studied. We found multiplicative and additive interactions between rs1537373 and obesity. When compared with GT/TT genotype and no obesity, GG genotype and obesity was associated with higher odds for periodontitis stage III-IV (OR=2.47, 95%CI=1.48-4.12, p=0.001; relative excess risk due to interaction=1.51, 95%CI=0.26-2.77, p=0.018; attributable proportion due to interaction=0.61; 95%CI=0.35-0.87, p<0.001). Conclusion Our findings suggest that rs1537373 GG genotype and obesity were jointly associated with periodontitis stage III-IV in this Norwegian population.