{"database":"GEO","file_versions":[{"headers":{"Content-Type":["application/json"]},"body":{"files":{"Other":["ftp://ftp.ncbi.nlm.nih.gov/geo/series/GSE297nnn/GSE297077/"]},"type":"primary"},"statusCode":"OK","statusCodeValue":200}],"scores":null,"additional":{"omics_type":["Genomics"],"species":["Arabidopsis thaliana"],"gds_type":["Genome binding/occupancy profiling by high throughput sequencing"],"full_dataset_link":["https://www.ncbi.nlm.nih.gov/geo/query/acc.cgi?acc=GSE297077"],"repository":["GEO"],"entry_type":["GSE"],"additional_accession":[]},"is_claimable":false,"name":"Mapping genetic modifiers of epimutation rates identifies VIM2/4 as dosage-sensitive negative regulators of CG methylation maintenance [ATAC-seq]","description":"Spontaneous epimutations—stochastic changes in cytosine methylation—can persist across generations in plants and are thought to contribute to phenotypic variation. Although epimutations are increasingly studied for their potential long-term effects, it remains unclear why their accumulation varies across genotypes. Here, we tracked DNA methylation across nine generations in ~400 mutation accumulation lineages derived from ~70 Arabidopsis Ler × Cvi recombinant inbred lines. Treating epimutation rates as quantitative molecular traits, we mapped a major QTL to a Cvi-derived deletion near VIM2 and VIM4, two genes involved in CG methylation (mCG) maintenance. We show that this deletion rapidly reduces genome-wide methylation to a lower steady-state and compromises mCG maintenance fidelity across generations, resulting in a ~1.5-fold increase in epimutation rates. Genotypes with elevated rates exhibited accelerated epigenetic drift and phenotypic divergence. Our findings support a punctuated-equilibrium model of mCG evolution, in which sudden disruptions to methylation homeostasis can destabilize epigenetic inheritance over longer time-scales.","dates":{"publication":"2026/07/18"},"accession":"GSE297077","cross_references":{"GSM":["GSM8983411","GSM8983410","GSM8983417","GSM8983416","GSM8983415","GSM8983414","GSM8983413","GSM8983412"],"GPL":["26208"],"GSE":["297077"],"taxon":["Arabidopsis thaliana"]}}