Exchange of subtelomeric regions between chromosomes 4q and 10q reverts the FSHD genotype and phenotype

Sci Adv. 2024 May 3;10(18):eadl1922. doi: 10.1126/sciadv.adl1922. Epub 2024 May 1.

Abstract

The most common form of facioscapulohumeral dystrophy (FSHD1) is caused by a partial loss of the D4Z4 macrosatellite repeat array in the subtelomeric region of chromosome 4. Patients with FSHD1 typically carry 1 to 10 D4Z4 repeats, whereas nonaffected individuals have 11 to 150 repeats. The ~150-kilobyte subtelomeric region of the chromosome 10q exhibits a ~99% sequence identity to the 4q, including the D4Z4 array. Nevertheless, contractions of the chr10 array do not cause FSHD or any known disease, as in most people D4Z4 array on chr10 is flanked by the nonfunctional polyadenylation signal, not permitting the DUX4 expression. Here, we attempted to correct the FSHD genotype by a CRISPR-Cas9-induced exchange of the chr4 and chr10 subtelomeric regions. We demonstrated that the induced t(4;10) translocation can generate recombinant genotypes translated into improved FSHD phenotype. FSHD myoblasts with the t(4;10) exhibited reduced expression of the DUX4 targets, restored PAX7 target expression, reduced sensitivity to oxidative stress, and improved differentiation capacity.

Publication types

  • Research Support, Non-U.S. Gov't
  • Research Support, N.I.H., Extramural

MeSH terms

  • CRISPR-Cas Systems
  • Chromosomes, Human, Pair 10* / genetics
  • Chromosomes, Human, Pair 4* / genetics
  • Genotype*
  • Homeodomain Proteins* / genetics
  • Homeodomain Proteins* / metabolism
  • Humans
  • Muscular Dystrophy, Facioscapulohumeral* / genetics
  • Myoblasts / metabolism
  • PAX7 Transcription Factor / genetics
  • PAX7 Transcription Factor / metabolism
  • Phenotype*
  • Telomere* / genetics
  • Telomere* / metabolism
  • Translocation, Genetic

Substances

  • DUX4L1 protein, human
  • Homeodomain Proteins
  • PAX7 protein, human
  • PAX7 Transcription Factor

Supplementary concepts

  • Facioscapulohumeral muscular dystrophy 1a