Fluoride Action Network



  • This study firstly aimed to establish the presence of these SNVs in AMELX, ODAM and MMP20, to determine their association with dental fluorosis in a population exposed to different concentrations of fluorine in the drinking water.
  • In our population, with high levels of fluoride in drinking water, exists differences in the susceptibility and severity of dental fluorosis.
  • MMP20 gene variation was present in the study group with high exposure to fluoride in the drinking water and associated with the less severe phenotypes of DF; thus, this SNV may be considered a marker of lesser DF susceptibility.

Objective: Dental fluorosis (DF) is a dental development disorder caused by chronic fluoride overconsumption. There are differences in the susceptibility to and severity of DF in studied populations. The objective of the present study was to determine if single-nucleotide variations (SNVs) in the genes Amelogenin (AMELX), Odontogenic Ameloblast Associated (ODAM) and Matrix Metalloproteinase 20 (MMP20) are associated with DF by evaluating the relationship between variations in these genes and the degree of DF severity.

Subjects and methods: Schoolchildren from two regions of Durango State and Mexico City, Mexico, were studied. The DF phenotype was determined using the Thylstrup and Fejerskov (TF) index. DNA was obtained from the buccal mucosa of each participant, and the presence of the variations rs946252 in AMELX, rs1514392 in ODAM and rs1784418 in MMP20 was determined by bidirectional DNA sequencing.

Results: A total of 180 DNA samples from 30 schoolchildren from 2 areas of Durango State were sequenced and analyzed. Differences in the severity of DF were found between the study areas (p = 0.006). SNVs in theMMP20 gene were present in 76.9 % of the participants in the high fluoride concentration and lower DF severity area.

Conclusion: AMELX and ODAM variations was not different between the two populations with respect to DF severity; however, the presence of rs1784418 differed between phenotypes with regard to susceptibility to DF. Therefore, MMP20 might be related to the various phenotypes of DF and may serve as a protective marker.

*Original abstract online at https://www.sciencedirect.com/science/article/pii/S0003996919308556