Youn Jung Kim1, Figen Seymen2, Jenny Kang3, Mine Koruyucu2, Nuray Tuloglu4, Sule Bayrak4, Elif Bahar Tuna2, Zang Hee Lee5, Teo Jeon Shin3, Hong-Keun Hyun3, Young-Jae Kim3, Sang-Hoon Lee3, Jan Hu6, James Simmer6, Jung-Wook Kim7,8. 1. Department of Molecular Genetics & Dental Research Institute, School of Dentistry, Seoul National University, Seoul, South Korea. 2. Department of Pedodontics, Faculty of Dentistry, Istanbul University, Istanbul, Turkey. 3. Department of Pediatric Dentistry & Dental Research Institute, School of Dentistry, Seoul National University, 275-1 Yongon-dong, Seoul, Chongno-gu, 110-768, South Korea. 4. Department of Pedodontics, Faculty of Dentistry, Eskisehir Osmangazi University, Eskisehir, Turkey. 5. Department of Cell and Developmental Biology & Dental Research Institute, School of Dentistry, Seoul National University, Seoul, South Korea. 6. Department of Biologic and Materials Sciences, University of Michigan Dental Research Lab, 1210 Eisenhower Place, Ann Arbor, MI, 48108, USA. 7. Department of Molecular Genetics & Dental Research Institute, School of Dentistry, Seoul National University, Seoul, South Korea. pedoman@snu.ac.kr. 8. Department of Pediatric Dentistry & Dental Research Institute, School of Dentistry, Seoul National University, 275-1 Yongon-dong, Seoul, Chongno-gu, 110-768, South Korea. pedoman@snu.ac.kr.
Abstract
OBJECTIVE: Amelogenesis imperfecta (AI) is a rare hereditary disorder affecting the quality and quantity of the tooth enamel. The purpose of this study was to identify the genetic etiology of hypoplastic AI families based on the candidate gene approach. MATERIALS AND METHODS: We recruited three Turkish families with hypoplastic AI and performed a candidate gene screening based on the characteristic clinical feature to find the pathogenic genetic etiology. RESULTS: The candidate gene sequencing of the LAMB3 gene for family 1 revealed a heterozygous nonsense mutation in the last exon [c.3431C > A, p.(Ser1144*)]. FAM20A gene sequencing for families 2 and 3 identified a homozygous deletion [c.34_35delCT, p.(Leu12Alafs*67)] and a homozygous deletion-insertion (c.1109 + 3_1109 + 7delinsTGGTC) mutation, respectively. CONCLUSION: The candidate gene approach can be successfully used to identify the genetic etiology of the AI in some cases with characteristic clinical features. CLINICAL RELEVANCE: Identification of the genetic etiology of the AI will help both the family members and dentist understand the nature of the disorder. Characteristic clinical feature can suggest possible genetic causes.
OBJECTIVE:Amelogenesis imperfecta (AI) is a rare hereditary disorder affecting the quality and quantity of the tooth enamel. The purpose of this study was to identify the genetic etiology of hypoplastic AI families based on the candidate gene approach. MATERIALS AND METHODS: We recruited three Turkish families with hypoplastic AI and performed a candidate gene screening based on the characteristic clinical feature to find the pathogenic genetic etiology. RESULTS: The candidate gene sequencing of the LAMB3 gene for family 1 revealed a heterozygous nonsense mutation in the last exon [c.3431C > A, p.(Ser1144*)]. FAM20A gene sequencing for families 2 and 3 identified a homozygous deletion [c.34_35delCT, p.(Leu12Alafs*67)] and a homozygous deletion-insertion (c.1109 + 3_1109 + 7delinsTGGTC) mutation, respectively. CONCLUSION: The candidate gene approach can be successfully used to identify the genetic etiology of the AI in some cases with characteristic clinical features. CLINICAL RELEVANCE: Identification of the genetic etiology of the AI will help both the family members and dentist understand the nature of the disorder. Characteristic clinical feature can suggest possible genetic causes.