MSH2 is not required for either maintenance of DNA methylation or repeat contraction at the FMR1 locus in fragile X syndrome or the FXN locus in Friedreich's ataxia.

ABSTRACT:

Background

Repeat-induced epigenetic changes are observed in many repeat expansion disorders (REDs). These changes result in transcriptional deficits and/or silencing of the associated gene. MSH2, a mismatch repair protein that is required for repeat expansion in the REDs, has been implicated in the maintenance of DNA methylation seen in the region upstream of the expanded CTG repeats at the DMPK locus in myotonic dystrophy type 1 (DM1). Here, we investigated the role of MSH2 in aberrant DNA methylation in two additional REDs, fragile X syndrome (FXS) that is caused by a CGG repeat expansion in the 5' untranslated region (UTR) of the Fragile X Messenger Ribonucleoprotein 1 (FMR1) gene, and Friedreich's ataxia (FRDA) that is caused by a GAA repeat expansion in intron 1 of the fratax

SUBMITTER: Grant-Bier J 

PROVIDER: S-EPMC12036138 | biostudies-literature | 2025 Apr

REPOSITORIES: biostudies-literature