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The phenotype and genotype of PAX9 mutations causing tooth agenesis
Cailing Jiang1,2, Kang Yu1, Yihan Shen1
1The 2nd Dental Center, Shanghai Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, College of Stomatology, Shanghai Jiao Tong University, National Center for Stomatology, National Clinical Research Center for Oral Diseases, Shanghai Key Laboratory of Stomatology, Shanghai, China.
Objectives:
The purpose of this study was to identify associations between PAX9 mutations and clinical features of non-syndromic tooth agenesis patients.
Materials And Methods:
Non-syndromic tooth agenesis patients were found to have mutations by whole exome sequencing (WES). Additionally, conservation analysis and three-dimensional structure prediction were also applied to identify mutated proteins.
Results:
Eight non-syndromic tooth agenesis probands were identified with PAX9 mutations (c.C112T; C.131_134del; c.G151A; c.189delG; c.305delT; c.C365A; c.394delG; c.A679C). All of the probands were missing more than six teeth (oligodontia). The mutations (c.131_134del,p.R44fs; c.189delG,p.T63fs; c.305delT,p.I102fs and c.394delG,p.G123fs) caused premature termination of the PAX9 protein. The c.C112T(p.R38X) mutation created a truncated protein. Bioinformatic prediction demonstrated that the three missense mutations change the PAX9 structure suggesting the corresponding functional impairments.
Conclusions:
We reported that eight mutations of PAX9 caused non-syndromic tooth agenesis and analyzed the relationship between PAX9 mutations and non-syndromic tooth agenesis.
Clinical Relevance:
Our study revealed that PAX9 mutations might be the mutations most associated with non-syndromic tooth agenesis in humans, which greatly broadened the mutation spectrum of PAX9-related non-syndromic tooth agenesis.
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