title: Morphological analyses and a novel de novo DLX3 mutation associated with tricho-dento-osseous syndrome in a Chinese family.
abstract: Tricho-dento-osseous (TDO) syndrome, an autosomal-dominant disorder, affects the morphological appearance of the tooth enamel, hair, and bone. Previous studies have confirmed that mutations in the DLX3 gene are responsible for TDO. In this study, we describe a Chinese patient with the typical traits of TDO - kinky hair, enamel hypoplasia, skull and jaw bones thickening, and sclerosis. Unfortunately, as a result of excessive attrition, we were unable to assess taurodontism. Examination of the tooth ground section showed a thin layer of enamel with no rods on the patient's tooth and abnormalities in Tomes' granular layer and the dentinal tubules. Scanning electron microscopy and energy-dispersive X-ray spectroscopy of the tooth enamel showed significant differences between the patient and the control individuals. A hair sample from the patient observed under a laser-scanning microscope showed longitudinal grooves in the hair shaft. Dual-energy X-ray absorptiometry measurement showed that the bone mineral density values of the patient's bones was much higher than normal. Finally, genetic analysis revealed a novel de novo missense mutation c.533A>G (p.Q178R) in the conserved homeodomain of the DLX3 gene. This DLX3 mutation is the sixth causative mutation for TDO to be identified so far.
authors.affiliation: Department of Prosthodontics, Peking University School and Hospital of Stomatology, Beijing, China.
authors.forename: Yue
authors.initials: Y
authors.lastname: Li
authors.affiliation: Department of Prosthodontics, Peking University School and Hospital of Stomatology, Beijing, China.
authors.forename: Dong
authors.initials: D
authors.lastname: Han
authors.affiliation: Department of Prosthodontics, Peking University School and Hospital of Stomatology, Beijing, China.
authors.forename: Hao
authors.initials: H
authors.lastname: Zhang
authors.affiliation: Department of Prosthodontics, Peking University School and Hospital of Stomatology, Beijing, China.
authors.forename: Haochen
authors.initials: H
authors.lastname: Liu
authors.affiliation: Department of Prosthodontics, Peking University School and Hospital of Stomatology, Beijing, China.
authors.forename: Singwai
authors.initials: S
authors.lastname: Wong
authors.affiliation: Department of Prosthodontics, Peking University School and Hospital of Stomatology, Beijing, China.
authors.forename: Na
authors.initials: N
authors.lastname: Zhao
authors.affiliation: The 4th Dental Division, Peking University School and Hospital of Stomatology, Beijing, China.
authors.forename: Lixin
authors.initials: L
authors.lastname: Qiu
authors.affiliation: Department of Prosthodontics, Peking University School and Hospital of Stomatology, Beijing, China.
authors.forename: Hailan
authors.initials: H
authors.lastname: Feng
mesh_terms: D015502:Absorptiometry, Photon; D000225:Adenine; D000328:Adult; D015519:Bone Density / Q000502:physiology; D002681:China; D017124:Conserved Sequence / Q000235:genetics; D019465:Craniofacial Abnormalities / Q000235:genetics* / Q000473:pathology; D003743:Dental Enamel / Q000002:abnormalities / Q000648:ultrastructure; D003744:Dental Enamel Hypoplasia / Q000235:genetics* / Q000473:pathology; D003804:Dentin / Q000002:abnormalities; D005091:Exons / Q000235:genetics; D005260:Female; D006147:Guanine; D006197:Hair / Q000002:abnormalities / Q000648:ultrastructure; D006201:Hair Diseases / Q000235:genetics* / Q000473:pathology; D018398:Homeodomain Proteins / Q000235:genetics*; D006801:Humans; D021621:Imaging, Three-Dimensional; D007438:Introns / Q000235:genetics; D018613:Microscopy, Confocal; D008855:Microscopy, Electron, Scanning; D020125:Mutation, Missense / Q000235:genetics*; D013052:Spectrometry, X-Ray Emission; D014157:Transcription Factors / Q000235:genetics*
chemical_list: C088334:Distal-less homeobox proteins; D018398:Homeodomain Proteins; D014157:Transcription Factors; D006147:Guanine; D000225:Adenine
keywords: DLX3; enamel hypoplasia; jaw bones thickening; kinky hair; tricho-dento-osseous syndrome