Severe infantile encephalomyopathy caused by a mutation in COX6B1, a nucleus-encoded subunit of cytochrome c oxidase

Am J Hum Genet. 2008 Jun;82(6):1281-9. doi: 10.1016/j.ajhg.2008.05.002. Epub 2008 May 22.


Cytochrome c oxidase (COX) deficiency, one of the most common respiratory-chain defects in humans, has been associated with mutations in either mitochondrial DNA genes or nucleus-encoded proteins that are not part in but promote the biogenesis of COX. Mutations of nucleus-encoded structural subunits were sought for but never found in COX-defective patients, leading to the conjecture that they may be incompatible with extra-uterine survival. We report a disease-associated mutation in one such subunit, COX6B1. Nuclear-encoded COX genes should be reconsidered and included in the diagnostic mutational screening of human disorders related to COX deficiency.

Publication types

  • Case Reports
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Amino Acid Sequence
  • Amino Acid Substitution
  • Base Sequence
  • Brain / pathology
  • Brain Diseases, Metabolic, Inborn / enzymology*
  • Brain Diseases, Metabolic, Inborn / genetics*
  • Brain Diseases, Metabolic, Inborn / pathology
  • Cell Nucleus / enzymology
  • Cell Nucleus / genetics
  • Child
  • Cytochrome-c Oxidase Deficiency / enzymology*
  • Cytochrome-c Oxidase Deficiency / genetics*
  • Cytochrome-c Oxidase Deficiency / pathology
  • Electron Transport Complex IV / chemistry
  • Electron Transport Complex IV / genetics*
  • Female
  • Genetic Complementation Test
  • Haplotypes
  • HeLa Cells
  • Humans
  • Infant
  • Magnetic Resonance Imaging
  • Male
  • Models, Molecular
  • Molecular Sequence Data
  • Pedigree
  • Point Mutation*
  • Protein Conformation
  • RNA Interference
  • Sequence Homology, Amino Acid


  • COX6B1 protein, human
  • Electron Transport Complex IV