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A Novel De Novo SP6 Mutation Causes Severe Hypoplastic Amelogenesis Imperfecta

ABSTRACT: Amelogenesis imperfecta (AI) is a heterogeneous group of rare genetic disorders affecting tooth enamel formation. Here we report an identification of a novel de novo missense mutation [c.817_818delinsAT, p.(Ala273Met)] in the SP6 gene, causing non-syndromic autosomal dominant AI. This is the second paper on amelogenesis imperfecta caused by SP6 mutation. Interestingly the identified mutation in this study is a 2-bp variant at the same nucleotide positions as the first report, but with AT instead of AA insertion. Clinical phenotype was much more severe compared to the previous report, and western blot showed an extremely decreased level of mutant protein compared to the wild-type, even though the mRNA level was similar.

SUBMITTER: Kim YJ

PROVIDER: S-EPMC7996877 | biostudies-literature | 2021 Feb

REPOSITORIES: biostudies-literature

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A Novel De Novo SP6 Mutation Causes Severe Hypoplastic Amelogenesis Imperfecta

Kim Youn Jung YJ Lee Yejin Y Zhang Hong H Song Ji-Soo JS Hu Jan C-C JC Simmer James P JP Kim Jung-Wook JW

Genes 20210226 3

Amelogenesis imperfecta (AI) is a heterogeneous group of rare genetic disorders affecting tooth enamel formation. Here we report an identification of a novel de novo missense mutation [c.817_818delinsAT, p.(Ala273Met)] in the SP6 gene, causing non-syndromic autosomal dominant AI. This is the second paper on amelogenesis imperfecta caused by SP6 mutation. Interestingly the identified mutation in this study is a 2-bp variant at the same nucleotide positions as the first report, but w ...[more]

PMID: 33652941

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