A novel mutation in NFKBIA/IKBA results in a degradation-resistant N-truncated protein and is associated with ectodermal dysplasia with immunodeficiency

Hum Mutat. 2008 Jun;29(6):861-8. doi: 10.1002/humu.20740.


Alterations in nuclear factor kappa B (NF-kappaB) essential modulator (NEMO; HUGO-approved symbol IKBKG) underlie most cases of ectodermal dysplasia with immune deficiency (EDI), a human disorder characterized by anhidrosis with diminished immunity. EDI has also been associated with a single heterozygous mutation at position Ser32 of the NF-kappaB inhibitor IkappaBalpha, one of two phosphorylation sites that are essential for targeting IkappaBalpha for proteasomal degradation and hence for activation of NF-kappaB. We report a novel heterozygous nonsense mutation in the IKBA (HUGO-approved symbol, NFKBIA) gene of a 1-year-old male child with EDI that introduces a premature termination codon at position Glu14. An in-frame methionine downstream of the nonsense mutation allows for reinitiation of translation. The resulting N-terminally truncated protein lacks both serine phosphorylation sites and inhibits NF-kappaB signaling by functioning as a dominant negative on NF-kappaB activity in lymphocytes and monocytes. These findings support the scanning model for translation initiation in eukaryotes and confirm the critical role of the NF-kappaB in the human immune response.

Publication types

  • Case Reports

MeSH terms

  • Amino Acid Sequence
  • Codon, Nonsense*
  • Ectodermal Dysplasia / genetics*
  • Humans
  • I-kappa B Kinase / chemistry
  • I-kappa B Kinase / genetics
  • I-kappa B Proteins / genetics*
  • Immunologic Deficiency Syndromes / genetics*
  • Infant
  • Male
  • Molecular Sequence Data
  • NF-KappaB Inhibitor alpha
  • NF-kappa B / immunology
  • Protein Biosynthesis
  • T-Lymphocytes / immunology


  • Codon, Nonsense
  • I-kappa B Proteins
  • NF-kappa B
  • NFKBIA protein, human
  • NF-KappaB Inhibitor alpha
  • I-kappa B Kinase