Linking Dental Arch Form and Body Mass Index via Genetic Variants within the Hippo Signaling Pathway

Hypothesis and Objective: Obesity and malocclusions are both problematic health conditions found throughout pediatric populations worldwide. We seek to determine whether a link exists between dental arch form and BMI via the genetic variants in the Hippo signaling pathway. Methods: Pre-treatment orthodontic records were collected from patients aged 7-17 years old (n=117). Digital dental models, height, and weight were analyzed. Body mass index was calculated: 703 x weight (lbs.) / [height (in)]2.3 DNA was extracted from saliva samples and amplicon sequencing was performed. Landmark Editor was used to digitally identify eighty coordinate landmarks on the maxillary and mandibular casts. Geometric morphometrics software, MorphoJ, was used to analyze shape variation of the casts. Results: For the phenotype data, Canonical Variate Analysis showed that there was a statistically significant association between wide mandibular arch form and obese BMI percentile (p=0.001). Principal Component Analysis also showed that the relationship between a wide mandibular arch phenotype for PC15 and obese BMI percentile was statistically significant (p=0.001). For the genotype-phenotype data, wide mandibular arch form phenotypes were associated with the following selected SNPs: rs13085791 on MST1, rs13205080 on LATS1, rs60842975 and rs6490637 on LATS2, rs4636447 and rs7522116 on FOXO6; and rs11758653 on TEAD3. Conclusion: While the maxillary arch did not show a significant relationship with BMI and the selected SNPs of genes along the Hippo signaling pathway, a wide mandibular arch phenotype was found to have a significant association with obese BMI and SNPs along the Hippo signaling pathway. Funding: AAOF. IRB/ACC protocol: 2017-1276.