CRISPR-AsCas12a Efficiently Corrects a GPR143 Intronic Mutation in Induced Pluripotent Stem Cells from an Ocular Albinism Patient

CRISPR J. 2022 Jun;5(3):457-471. doi: 10.1089/crispr.2021.0110.

Abstract

Mutations in the GPR143 gene cause X-linked ocular albinism type 1 (OA1), a disease that severely impairs vision. We recently generated induced pluripotent stem cells (iPSCs) from skin fibroblasts of an OA1 patient carrying a point mutation in intron 7 of GPR143. This mutation activates a new splice site causing the incorporation of a pseudoexon. In this study, we present a high-performance CRISPR-Cas ribonucleoprotein strategy to permanently correct the GPR143 mutation in these patient-derived iPSCs. Interestingly, the two single-guide RNAs available for SpCas9 did not allow the cleavage of the target region. In contrast, the cleavage achieved with the CRISPR-AsCas12a system promoted homology-directed repair at a high rate. The CRISPR-AsCas12a-mediated correction did not alter iPSC pluripotency or genetic stability, nor did it result in off-target events. Moreover, we highlight that the disruption of the pathological splice site caused by CRISPR-AsCas12a-mediated insertions/deletions also rescued the normal splicing of GPR143 and its expression level.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Albinism, Ocular* / genetics
  • Albinism, Ocular* / metabolism
  • Albinism, Ocular* / pathology
  • CRISPR-Cas Systems / genetics
  • Eye Proteins / genetics
  • Eye Proteins / metabolism
  • Gene Editing
  • Humans
  • Induced Pluripotent Stem Cells* / metabolism
  • Membrane Glycoproteins / genetics
  • Membrane Glycoproteins / metabolism
  • Mutation

Substances

  • Eye Proteins
  • GPR143 protein, human
  • Membrane Glycoproteins

Supplementary concepts

  • Ocular Albinism type 1