Face-Shape Genes Influencing Malocclusion
Presentation Category
Research
Introduction/Context/Diagnosis
Etiology of malocclusions and relative contributions of genetic and environmental factors have been a matter of debate in orthodontics for many years. Personalized orthodontic treatment and prevention strategies will constitute a big step forward in orthodontics. One of the first steps towards this paradigm shift would be identification of relationships between genotype and phenotype of malocclusions. Studies showed that many genes and environmental factors are collectively asserting their influence during formation of a phenotype. Despite this complexity, the study of etiology of malocclusions is fundamental for understanding of cellular processes underlying craniofacial growth and development of dental relations.
Methods/Treatment Plan
A review of literature was done using three search engines (PubMed, Scorpius, Google Scholar) and keywords: genotype, phenotype, craniofacial, genetics, genomic medicine, genotype–phenotype correlation, phenomics, Class I, II and III malocclusions, and face-shape genes. The search was run with no language restrictions and covered the 1980 – 2019 time period.
Results/Outcome
The search yielded 14 articles. Majority of studies focused on Class III malocclusion and showed linkage and association with a cluster of genes on chromosome 1 and chromosome 12. Studies on mandibular prognathism identified associations with genes located within the 1p22-p36 and 12q13-q24 loci. Genetic studies on Class II are less frequent. Studies on phenotypic diversity of Class II and Class III malocclusions showed differences in anterior-posterior (AP) position of the mandible compared to the cranial base, relative sizs of ramus and body of the mandible, vertical mandibular rotation, incisor angulation. With respect to genotype-phenotype interactions, several genes are known to play important roles in craniofacial development or in syndromes affecting the face: MAFB, PAX9, MIPOL1, ALX3, HDAC8, and PAX1. Such studies have converged to an important finding. Genes implicated in bone development (TGFB3, LTBP, IGF1, ENPP1, EVC, and EVC2), cartilage development (Matrilin-1 and COI2A1), muscle development (MYO1H and DUSP6) and tooth morphogenesis (EDA, XEDAR, and BMP2) may be putative candidates for development of jaw and tooth size discrepancies.
Significance/Conclusions
Phenotype-genotype correlation studies of malocclusions are greatly needed, as the knowledge gained from them will aid in our understanding of mechanisms responsible for development of human malocclusions and craniofacial anomalies. Comprehensive studies of gene variants and corresponding phenotypes may help to identify patients who would respond to orthopedic or orthodontic treatment favorably or adversely, thus making practice more rewarding for clinicians and more pleasant for patients.
Format
Event
Face-Shape Genes Influencing Malocclusion
Etiology of malocclusions and relative contributions of genetic and environmental factors have been a matter of debate in orthodontics for many years. Personalized orthodontic treatment and prevention strategies will constitute a big step forward in orthodontics. One of the first steps towards this paradigm shift would be identification of relationships between genotype and phenotype of malocclusions. Studies showed that many genes and environmental factors are collectively asserting their influence during formation of a phenotype. Despite this complexity, the study of etiology of malocclusions is fundamental for understanding of cellular processes underlying craniofacial growth and development of dental relations.
Comments/Acknowledgements
Key Words: genotype, phenotype, craniofacial, genetics, genomic medicine, genotype–phenotype correlation, phenomics, Class I, II and III malocclusions, face-shape genes