Blood Advances (Jan 2017)

Gene-edited pseudogene resurrection corrects p47phox-deficient chronic granulomatous disease

  • Randall K. Merling,
  • Douglas B. Kuhns,
  • Colin L. Sweeney,
  • Xiaolin Wu,
  • Sandra Burkett,
  • Jessica Chu,
  • Janet Lee,
  • Sherry Koontz,
  • Giovanni Di Pasquale,
  • Sandra A. Afione,
  • John A. Chiorini,
  • Elizabeth M. Kang,
  • Uimook Choi,
  • Suk See De Ravin,
  • Harry L. Malech

DOI
https://doi.org/10.1182/bloodadvances.2016001214
Journal volume & issue
Vol. 1, no. 4
pp. 270 – 278

Abstract

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Abstract: Pseudogenes are duplicated genes with mutations rendering them nonfunctional. For single-gene disorders with homologous pseudogenes, the pseudogene might be a target for genetic correction. Autosomal-recessive p47phox-deficient chronic granulomatous disease (p47-CGD) is a life-threatening immune deficiency caused by mutations in NCF1, a gene with 2 pseudogenes, NCF1B and NCF1C. The most common NCF1 mutation, a GT deletion (ΔGT) at the start of exon 2 (>90% of alleles), is constitutive to NCF1B and NCF1C. NCF1 ΔGT results in premature termination, undetectable protein expression, and defective production of antimicrobial superoxide in neutrophils. We examined strategies for p47-CGD gene correction using engineered zinc-finger nucleases targeting the exon 2 ΔGT in induced pluripotent stem cells or CD34+ hematopoietic stem cells derived from p47-CGD patients. Correction of ΔGT in NCF1 pseudogenes restores oxidase function in p47-CGD, providing the first demonstration that targeted restoration of pseudogene function can correct a monogenic disorder.