A dynamic trinucleotide repeat (TNR) expansion in the DMD gene

Mol Cell Probes. 2016 Aug;30(4):254-260. doi: 10.1016/j.mcp.2016.07.001. Epub 2016 Jul 12.

Abstract

Dystrophinopathies are allelic X-linked myopathies caused by large deletions/duplications or small lesions along the DMD gene. An unexpected dynamic trinucleotide (GAA) expansion, ranging from ∼59 to 82 pure GAA repeats, within the DMD intron 62, was revealed to segregate through three family generations. From the pedigree, two female patients were referred for DMD investigation due to chronic myopathy and a muscle biopsy compatible with dystrophinopathy. As the size of the GAA repeat is limited to 11-33 within the general population our findings may provide a novel insight towards a Trinucleotide Repeat Expansion. Whether this TNR has an impact on the reported phenotype remains to be resolved.

Keywords: BMD; DMD; Dystrophin; Manifesting carriers; Trinucleotide expansion.

Publication types

  • Case Reports
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adolescent
  • Adult
  • Base Sequence
  • Child
  • DNA Methylation / genetics
  • Dystrophin / chemistry
  • Dystrophin / genetics*
  • Female
  • Humans
  • Male
  • Muscular Dystrophy, Duchenne / genetics
  • Pedigree
  • Trinucleotide Repeats / genetics*

Substances

  • DMD protein, human
  • Dystrophin