Genetic variations in MMP9 and MMP13 contribute to tooth agenesis in a Brazilian population.

We investigated the association between polymorphisms in the MMP2 (rs243865), MMP9 (rs17576), and MMP13 (rs2252070) genes with tooth agenesis in humans. Two hundred eighty-five unrelated individuals (202 controls without tooth agenesis and 83 cases with tooth agenesis) were evaluated in a cross-sectional single-center study. The study participants were recruited through the Pediatric Dental Clinics of the Federal University of Rio de Janeiro, Brazil. Genotyping of the selected polymorphisms for MMPs was carried out by real-time PCR using the Taqman assay method from genomic DNA isolated from buccal epithelial cells of all the studied individuals. There was no significant association of MMP2 genotype or allele distribution with tooth agenesis or its absence. For MMP9, a significant difference in allele frequency was evident between the two groups (P = 0.05). With regard to the affected side, there was a significant difference between unilateral tooth agenesis and the control group in the distribution of MMP9 (P = 0.05). Also, there was a significant difference in MMP9 distribution between tooth agenesis in the maxilla and control individuals (P = 0.03). The genotype distribution of MMP13 differed significantly between the group with unilateral tooth agenesis and the controls (P = 0.01). Our findings provide evidence that MMP9 and MMP13 may be involved in tooth agenesis.