Disorders of H2O2 generation

Best Pract Res Clin Endocrinol Metab. 2017 Mar;31(2):225-240. doi: 10.1016/j.beem.2017.04.006. Epub 2017 May 10.


After the identification of thyroid H2O2 generation system (DUOX) and of its maturation factors (DUOXA), defects in DUOX2 and/or DUOXA2 were rapidly recognized as the possible cause of congenital hypothyroidism (CH) due to thyroid dyshormonogenesis. The present Review reports data on the prevalence of DUOX2 mutations, which is variable among different series but invariably high, pointing to DUOX2 defects as one of the leading causes of dyshormonogenesis. Differently, DUOXA defects seem to be rarely involved in the pathogenesis of CH. Genotype-phenotype correlations are also reported, highlighting the great intra- and inter-familial phenotype variability which appears to be a constant feature of the defects in the H2O2 generation systems. Finally, the hypotheses to explain the phenotypic variability of the DUOX2/A2 mutations are discussed, such as the existence of other H2O2 generating systems, the age variability in thyroid hormones requirements, the differences in ethnicity, in iodine intake, and in the methodological approaches.

Keywords: DUOX; DUOXA; congenital hypothyroidism; dyshormonogenesis.

Publication types

  • Review

MeSH terms

  • Congenital Hypothyroidism / drug therapy
  • Congenital Hypothyroidism / epidemiology
  • Congenital Hypothyroidism / genetics
  • Congenital Hypothyroidism / metabolism*
  • Dual Oxidases / genetics
  • Dual Oxidases / metabolism*
  • Gene Frequency
  • Genetic Heterogeneity
  • Humans
  • Hydrogen Peroxide / metabolism*
  • Membrane Proteins / genetics
  • Membrane Proteins / metabolism*
  • Mutation
  • Phenotype
  • Prevalence
  • Thyroid Hormones / metabolism
  • Thyroid Hormones / therapeutic use


  • DUOXA2 protein, human
  • Membrane Proteins
  • Thyroid Hormones
  • Hydrogen Peroxide
  • Dual Oxidases
  • DUOX2 protein, human