<i> <scp>COX</scp> ‐2 </i> gene polymorphisms and risk of chronic periodontitis: a case–control study and meta‐analysis
Cyclooxygenase-2 (COX-2) enzyme is a major mediator of inflammation in periodontitis, leading to loss of gingival tissues and alveolar bone supporting the teeth. Previous studies have explored the role of COX-2 polymorphisms with the risk of periodontitis in different ethnic groups; however, findings are inconsistent. So, we aimed to investigate the association of COX-2 polymorphisms (rs20417, rs689466, and rs5275) in susceptibility to chronic periodontitis (CP) in northern Indian population. Meta-analysis was also carried out to precisely estimate the effect of COX-2 polymorphisms in CP.Genotyping of COX-2 polymorphisms was carried out through PCR-RFLP in 200 CP cases and 200 controls. For risk estimation, binary logistic regression was applied using SPSS, version 15.0, while meta-analysis was carried using MIX 2.0 software.None of the COX-2 polymorphisms independently were associated with the risk of CP. Meta-analysis suggested a significant reduced risk of CP with rs5275+8473 C allele and rs20417 in Chinese population.No association was observed in any of the studied COX-2 polymorphisms with CP in North India. But, the study should be replicated in larger sample size to arrive at a definitive conclusion. Meta-analysis suggested a role of rs5275 COX-2 polymorphisms in susceptibility to overall CP, and on ethnic basis, rs20417 showed reduced risk of CP in Chinese population.