Journal of Genetic Medicine

Korean Society of Medical Genetics and Genomics (대한의학유전학회)
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Smith-Kingsmore syndrome: The first report of a Korean patient with the MTOR germline mutation c.5395G>A p.(Glu1799Lys)

  • Lee, Dohwan (Department of Pediatrics, Nowon Eulji Medical Center, Eulji University) ;
  • Jang, Ja-Hyun (GC Genome) ;
  • Lee, Cha Gon (Department of Pediatrics, Nowon Eulji Medical Center, Eulji University)
  • Received : 2018.11.26
  • Accepted : 2019.01.02
  • Published : 2019.06.30
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Abstract

Smith-Kingsmore syndrome (SKS; OMIM 616638), also known as macrocephaly-intellectual disability-neurodevelopmental disorder-small thorax syndrome (MINDS; ORPHA 457485), is a rare autosomal dominant disorder, the prevalence of which is not known. It is caused by a heterozygous germline mutation in MTOR (OMIM 601231). Ten different MTOR germline mutations in 27 individuals have been reported in the medical literature to date. These were all gain-of-function missense variants, and about half of the 27 individuals had c.5395G>A p.(Glu1799Lys) in MTOR. Here, I report for the first time a Korean patient with the heterozygous germline mutation c.5395G>A p.(Glu1799Lys) in MTOR. It was found to be a de novo mutation, which was identified by whole-exome sequencing and confirmed by Sanger sequencing. The patient showed typical clinical features of SKS, including macrocephaly/megalencephaly; moderate intellectual disability; seizures; behavioral problems; and facial dysmorphic features of curly hair, frontal bossing, midface hypoplasia, and hypertelorism.

Keywords

References

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