Two novel EIF2S3 mutations associated with syndromic intellectual disability with severe microcephaly, growth retardation, and epilepsy

Am J Med Genet A. 2016 Nov;170(11):2927-2933. doi: 10.1002/ajmg.a.37792. Epub 2016 Jun 22.

Abstract

X-chromosome exome sequencing was performed to identify the genetic cause of syndromic intellectual disability in two unrelated families with suspected X-linked inheritance. In both families, affected males presented with severe intellectual disability, microcephaly, growth retardation, and epilepsy. A missense mutation (c.777T>G p.(Ile259Met)) and a frameshift mutation (c.1394_1397del p.(Ile465Serfs*4)) were identified in the EIF2S3 gene in the hemizygous state in affected patients, and in the heterozygous states female obligate carriers. A missense mutation in EIF2S3, coding for the gamma-subunit of the translation initiation factor eIF2, was reported once in a family presenting with similar clinical features. Morpholino-based knockdown of the zebrafish EIF2S3 ortholog (eif2s3) recapitulates the human microcephaly and short stature phenotype, supporting the pathogenicity of the identified variants. Our data confirm that EIF2S3 mutation is implicated in a rare, but recognizable, form of syndromic intellectual disability. © 2016 Wiley Periodicals, Inc.

Keywords: X-exome sequencing; X-linked intellectual disability; epilepsy; microcephaly; morpholino; zebrafish.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adolescent
  • Alleles
  • Amino Acid Sequence
  • Animals
  • Brain / pathology
  • Disease Models, Animal
  • Epilepsy / diagnosis
  • Epilepsy / genetics*
  • Eukaryotic Initiation Factor-2 / genetics*
  • Exome
  • Facies
  • Female
  • Gene Knockdown Techniques
  • Genes, X-Linked
  • Genetic Association Studies*
  • Genotype
  • Growth Disorders / diagnosis
  • Growth Disorders / genetics*
  • High-Throughput Nucleotide Sequencing
  • Humans
  • Intellectual Disability / diagnosis
  • Intellectual Disability / genetics*
  • Magnetic Resonance Imaging
  • Male
  • Microcephaly / diagnosis
  • Microcephaly / genetics*
  • Mutation*
  • Pedigree
  • Phenotype
  • Syndrome
  • Zebrafish

Substances

  • Eukaryotic Initiation Factor-2