| Institution: | 1. https://orcid.org/0000-0001-9841-0881;2. Center of Excellence in Medical Genetics Research, Chiang Mai University, Chiang Mai, Thailand;3. Division of Pediatric Dentistry, Department of Orthodontics and Pediatric Dentistry, Faculty of Dentistry, Chiang Mai University, Chiang Mai, Thailand;4. Dentaland Clinic, Chiang Mai, Thailand;5. Piranit N. Kantaputra, D.D.S., M.S., Division of Pediatric Dentistry, Department of Orthodontics and Pediatric Dentistry, Faculty of Dentistry, Chiang Mai University, Chiang Mai 50200, Thailand.;6. Department of Neurosurgery, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania;7. Department of Orthopaedic Surgery, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania;8. Department of Clinical Sciences and Advanced Medicine, School of Veterinary Medicine, University of Pennsylvania, Philadelphia, Pennsylvania;9. Department of Pediatrics, College of Medicine, Rangsit University, Bangkok, Thailand;10. Division of Genetics, Queen Sirikit National Institute of Child Health, Department of Medical Services, Ministry of Public Health, Bangkok, Thailand;11. Department of Periodontics, School of Dental Medicine, University of Pennsylvania, Philadelphia, Pennsylvania;12. Department of Pediatric Genetics, Amrita Institute of Medical Sciences & Research Centre, AIMS Ponekkara PO, Cochin, Kerala, India;13. Jomthong Hospital, Chiang Mai, Thailand;14. Saraburi Provincial Health Office, Saraburi, Thailand;15. Center for Medical Genomics, Bangkok, Thailand;16. School of Chemistry, Institute of Science, and Center for Biomolecular Structure, Function and Application, Suranaree University of Technology, Nakhon Ratchasima, Thailand;17. Laboratory of Biochemistry, Chulabhorn Research Institute, Bangkok, Thailand;18. Children's Rare Disease Institute, Washington, District of Columbia |
| Abstract: | Mucopolysaccharidosis Type VII (MPS7, also called β‐glucuronidase deficiency or Sly syndrome; MIM 253220) is an extremely rare autosomal recessive lysosomal storage disease, caused by mutations in the GUSB gene. β‐glucuronidase (GUSB) is a lysosomal hydrolase involved in the stepwise degradation of glucuronic acid‐containing glycosaminoglycans (GAGs). Patients affected with MPS VII are not able to completely degrade glucuronic acid‐containing GAGs, including chondroitin 4‐sulfate, chondroitin 6‐sulfate, dermatan sulfate, and heparan sulfate. The accumulation of these GAGs in lysosomes of various tissues leads to cellular and organ dysfunctions. Characteristic features of MPS VII include short stature, macrocephaly, hirsutism, coarse facies, hearing loss, cloudy cornea, short neck, valvular cardiac defects, hepatosplenomegaly, and dysostosis multiplex. Oral manifestations in patients affected with MPS VII have never been reported. Oral manifestations observed in three patients consist of wide root canal spaces, taurodontism, hyperplastic dental follicles, malposition of unerupted permanent molars, and failure of tooth eruption with malformed roots. The unusual skeletal features of the patients include maxillary hypoplasia, hypoplastic midface, long mandibular length, mandibular prognathism, hypoplastic and aplastic mandibular condyles, absence of the dens of the second cervical vertebra, and erosion of the cortex of the lower border of mandibles. Dogs affected with MPS VII had anterior and posterior open bite, maxillary hypoplasia, premolar crowding, and mandibular prognathism. Unlike patients with MPS VII, the dogs had unremarkable mandibular condyles. This is the first report of oral manifestations in patients affected with MPS VII. |
