Haematologica (May 2010)

Erythrocytosis associated with a novel missense mutation in the HIF2A gene

  • Richard van Wijk,
  • Scott Sutherland,
  • Annet C.W. Van Wesel,
  • Eric G. Huizinga,
  • Melanie J. Percy,
  • Marc Bierings,
  • Frank S. Lee

DOI
https://doi.org/10.3324/haematol.2009.017582
Journal volume & issue
Vol. 95, no. 5

Abstract

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The ERYTHROPOIETIN (EPO) gene is regulated by the transcription factor Hypoxia Inducible Factor-α (HIF-α). In this pathway, Prolyl Hydroxylase Domain protein 2 (PHD2) hydroxylates two prolyl residues in HIF-α, which in turn promotes HIF-α degradation by the von Hippel Lindau (VHL) protein. Evidence that HIF-2α is the important isoform for EPO regulation in humans comes from the recent observation that mutations in the HIF2A gene are associated with cases of erythrocytosis. We report here a new erythrocytosis-associated mutation, p.Asp539Glu, in the HIF2A gene. Similar to all reported cases, the affected residue is in close vicinity and C-terminal to the primary hydroxylation site in HIF-2α, Pro531. This mutation, however, is notable in producing a rather subtle amino acid substitution. Nonetheless, we find that this mutation compromises binding of HIF-2α to both PHD2 and VHL, and we propose that this mutation is the cause of erythrocytosis in this individual.