DNA Mismatch Repair and its Role in Huntington’s Disease

• Published in: Journal of Huntington's disease Vol. 10; no. 1; pp. 75 - 94
• Main Authors: Iyer, Ravi R., Pluciennik, Anna
• Format: Journal Article
• Language: English
• Published: London, England SAGE Publications 01.01.2021; Sage Publications Ltd; IOS Press
• Subjects: Chromosome rearrangements; Deoxyribonucleic acid; DNA; DNA biosynthesis; DNA damage; DNA repair; Genomes; Huntington's disease; Huntingtons disease; Mismatch repair; Neurodegenerative diseases; Polyglutamine; Review; Trinucleotide repeat diseases; Trinucleotide repeats; neurodegeneration; somatic expansion; Huntington’s disease; triplet repeat instability; DNA structures; DNA mismatch repair
• ISSN: 1879-6397; 1879-6397; 1879-6400
• DOI: 10.3233/JHD-200438

DNA mismatch repair (MMR) is a highly conserved genome stabilizing pathway that corrects DNA replication errors, limits chromosomal rearrangements, and mediates the cellular response to many types of DNA damage. Counterintuitively, MMR is also involved in the generation of mutations, as evidenced by its role in causing somatic triplet repeat expansion in Huntington’s disease (HD) and other neurodegenerative disorders. In this review, we discuss the current state of mechanistic knowledge of MMR and review the roles of key enzymes in this pathway. We also present the evidence for mutagenic function of MMR in CAG repeat expansion and consider mechanistic hypotheses that have been proposed. Understanding the role of MMR in CAG expansion may shed light on potential avenues for therapeutic intervention in HD.