The functional (−1171 5A→6A) polymorphisms of matrix metalloproteinase 3 gene as a risk factor for oral submucous fibrosis among male areca users

Background: Insertion/deletion (−1171 5A→6A) polymorphisms in the promoter region of matrix metalloproteinase 3 ( MMP3 ) gene result in different transcriptional activities. MMP3 is able to degrade collagens types II, V, IX, and X, and other extracellular matrix. The functional promoter polymorphism of MMP3 has been related to the susceptibility in some inflammatory diseases and metastasis of cancers. Methods: Oral submucous fibrosis (OSF) and oral squamous cell carcinoma (OSCC) are prevalent among Asian areca users. In this study, genomic DNA obtained from the blood of OSCC ( n = 150), OSF ( n = 71), and control non‐diseased areca user ( n = 98) in male were subjected to polymerase chain reaction (PCR)‐based genotyping of MMP3 . Results: The 5A genotype in MMP3 promoter was observed more frequently in OSF group than in control group ( P = 0.01). No significant difference was noted between OSCC and control groups on the 5A genotype frequency ( P = 0.18). No association was found between 5A genotype in MMP3 promoter and site or lymph node metastasis and stage of OSCC. Conclusion: The results indicated that the 5A genotype of MMP3 promoter was associated with the risk of OSF but not OSCC.