Table 1 Epigenetic mechanisms of genetic instability
Influence on repetitive elements | Epigenetic involvement | Molecular consequence |
|---|---|---|
Direct | Transcriptional repression of repetitive elements by DNA methylation | Prevents DNA damage produced by DNA secondary structures or homologous recombination |
Chromatin remodeling by DNMTs | Chromatin condensation reduces DNA exposure to mutagenic factors or processes | |
Involvement of DNMTs in DNA repair | DNMT1 interaction with the MMR machinery facilitates DNA repair | |
Indirect | Hypermethylation of DNA repair genes (i.e., MMR) | Reduced expression of genes required for genetic stability |