Subject(s)
Amelogenesis Imperfecta/complications , Amelogenesis Imperfecta/diagnosis , Asthma/complications , Asthma/diagnosis , Heart Defects, Congenital/complications , Heart Defects, Congenital/diagnosis , Nephrocalcinosis/complications , Nephrocalcinosis/diagnosis , Amelogenesis Imperfecta/drug therapy , Asthma/drug therapy , Biomarkers , Child , Echocardiography, Doppler, Color , Heart Defects, Congenital/drug therapy , Humans , Male , Morocco , Nephrocalcinosis/drug therapy , Phenotype , Radiography , Tomography, X-Ray ComputedABSTRACT
BACKGROUND: Orodental diseases include several clinically and genetically heterogeneous disorders that can present in isolation or as part of a genetic syndrome. Due to the vast number of genes implicated in these disorders, establishing a molecular diagnosis can be challenging. We aimed to develop a targeted next-generation sequencing (NGS) assay to diagnose mutations and potentially identify novel genes mutated in this group of disorders. METHODS: We designed an NGS gene panel that targets 585 known and candidate genes in orodental disease. We screened a cohort of 101 unrelated patients without a molecular diagnosis referred to the Reference Centre for Oro-Dental Manifestations of Rare Diseases, Strasbourg, France, for a variety of orodental disorders including isolated and syndromic amelogenesis imperfecta (AI), isolated and syndromic selective tooth agenesis (STHAG), isolated and syndromic dentinogenesis imperfecta, isolated dentin dysplasia, otodental dysplasia and primary failure of tooth eruption. RESULTS: We discovered 21 novel pathogenic variants and identified the causative mutation in 39 unrelated patients in known genes (overall diagnostic rate: 39%). Among the largest subcohorts of patients with isolated AI (50 unrelated patients) and isolated STHAG (21 unrelated patients), we had a definitive diagnosis in 14 (27%) and 15 cases (71%), respectively. Surprisingly, COL17A1 mutations accounted for the majority of autosomal-dominant AI cases. CONCLUSIONS: We have developed a novel targeted NGS assay for the efficient molecular diagnosis of a wide variety of orodental diseases. Furthermore, our panel will contribute to better understanding the contribution of these genes to orodental disease. TRIAL REGISTRATION NUMBERS: NCT01746121 and NCT02397824.
Subject(s)
High-Throughput Nucleotide Sequencing/methods , Mutation , Tooth Abnormalities/genetics , Amelogenesis Imperfecta/genetics , Autoantigens/genetics , Chromosome Deletion , Chromosome Disorders/genetics , Chromosomes, Human, Pair 11/genetics , Cohort Studies , Coloboma/genetics , Dentin Dysplasia/genetics , France , Hearing Loss, Sensorineural/genetics , Humans , Non-Fibrillar Collagens/genetics , Reproducibility of Results , Collagen Type XVIIABSTRACT
INTRODUCTION: Amelogenesis imperfecta is an inherited disease characterized by generalized structural abnormalities of the enamel on all teeth, including both primary and permanent dentition. To the best of our knowledge, this is the first case report of a rare association of amelogenesis imperfecta, platyspondyly, and bicytopenia. CASE PRESENTATION: A 5-year-old Moroccan boy was examined in the Centre for Dental Consultation and Treatment, Faculty of Dentistry, Rabat. He was a child of consanguineous parents (first degree). The child failed to thrive (-4 standard deviation score) and displayed delayed overall development. A dental examination revealed a hypoplastic amelogenesis imperfecta with a bacterial biofilm deposit on tooth surfaces. A complete blood count revealed bicytopenia (normocytic-normochromic anemia with thrombocytopenia). A radiographic examination of the spinal column showed a deviation of the spine in the frontal plane in the form of thoracolumbar scoliosis. The interpedicular distance was not expanded; but a mild platyspondyly exists, especially pronounced in T11 and T12. CONCLUSIONS: No other family members presented amelogenesis imperfecta, bicytopenia, or platyspondyly. The consanguineous marriage suggested an autosomal recessive mode of inheritance. Further studies are necessary to clarify the genetic defect producing this syndrome, and the symptomatic associations of amelogenesis imperfecta, platyspondyly and bicytopenia.
