N Intarak1, T Theerapanon2, C Ittiwut3,4, K Suphapeetiporn3,4, T Porntaveetus1, V Shotelersuk3,4. 1. Craniofacial Genetics and Stem Cells Research Group, Department of Physiology, Faculty of Dentistry, Chulalongkorn University, Bangkok, Thailand. 2. Excellence Center in Regenerative Dentistry, Faculty of Dentistry, Chulalongkorn University, Bangkok, Thailand. 3. Center of Excellence for Medical Genetics, Department of Pediatrics, Faculty of Medicine, Chulalongkorn University, Bangkok, Thailand. 4. Excellence Center for Medical Genetics, King Chulalongkorn Memorial Hospital, The Thai Red Cross Society, Bangkok, Thailand.
Abstract
OBJECTIVE: To identify orodental characteristics and genetic aetiology of a family affected with non-syndromic orodental anomalies. SUBJECTS AND METHODS: Physical and oral features were characterised. DNA was collected from an affected Thai family. Whole-exome sequencing was employed to identify the pathogenic variants associated with inherited orodental anomalies. The presence of the identified mutation was confirmed by Sanger sequencing. RESULTS: We observed unique orodental manifestations including oligodontia, retained primary teeth, taurodont molars, peg-shaped maxillary central incisors, high attached frenum with nodule and midline diastema in the proband and her mother. Mutation analyses revealed a novel heterozygous frameshift deletion, c.573_574delCA, p.L193QfsX5, in exon 5 of PITX2A in affected family members. The amino acid alterations, localised in the transcriptional activation domain 2 in the C-terminus of PITX2, were evolutionarily conserved. Mutations in PITX2 have been associated with autosomal-dominant Axenfeld-Rieger syndrome and non-syndromic eye abnormalities, but never been found to cause isolated oral anomalies. CONCLUSIONS: This study for the first time demonstrates that the PITX2 mutation could lead to non-syndromic orodental anomalies in humans. We propose that the specific location in the C-terminal domain of PITX2 is exclusively necessary for tooth development.
OBJECTIVE: To identify orodental characteristics and genetic aetiology of a family affected with non-syndromic orodental anomalies. SUBJECTS AND METHODS: Physical and oral features were characterised. DNA was collected from an affected Thai family. Whole-exome sequencing was employed to identify the pathogenic variants associated with inherited orodental anomalies. The presence of the identified mutation was confirmed by Sanger sequencing. RESULTS: We observed unique orodental manifestations including oligodontia, retained primary teeth, taurodont molars, peg-shaped maxillary central incisors, high attached frenum with nodule and midline diastema in the proband and her mother. Mutation analyses revealed a novel heterozygous frameshift deletion, c.573_574delCA, p.L193QfsX5, in exon 5 of PITX2A in affected family members. The amino acid alterations, localised in the transcriptional activation domain 2 in the C-terminus of PITX2, were evolutionarily conserved. Mutations in PITX2 have been associated with autosomal-dominant Axenfeld-Rieger syndrome and non-syndromic eye abnormalities, but never been found to cause isolated oral anomalies. CONCLUSIONS: This study for the first time demonstrates that the PITX2 mutation could lead to non-syndromic orodental anomalies in humans. We propose that the specific location in the C-terminal domain of PITX2 is exclusively necessary for tooth development.
Authors: Valeria Lo Faro; Sorath N Siddiqui; Muhammad I Khan; Cristina Villanueva-Mendoza; Vianney Cortés-González; Nomdo Jansonius; Arthur A B Bergen; Shazia Micheal Journal: Mol Genet Genomic Med Date: 2020-05-13 Impact factor: 2.183