Since genetic variants in WNT/ -catenin signaling, including I LRP5 i , I LRP6 i , and I WLS i were implicated in mesiodens,[1] we hypothesized that genetic variants in DKK1, an inhibitor of WNT/ -catenin signaling, might be associated with the mesiodens phenotype as well. Keywords: mesiodens; supernumerary tooth; taurodontism; WNT signaling EN mesiodens supernumerary tooth taurodontism WNT signaling 714 716 3 05/03/23 20230601 NES 230601 A mutation in DKK1 gene leads to inhibitory DKK1 function, over-activation of WNT/ -catenin signaling, disruptive development of dental epithelium, and subsequent mesiodens formation. It is hypothesized that the increased inhibition by the DKK1 mutant protein, as shown by TOPFLASH reporter assay, disrupted WNT- -catenin signaling and resulted in mesiodens and taurodontism. [Extracted from the article]