New publication in "iScience"
Epigenome editing is the targeted epigenomic reprogramming of genomic loci using a so-called epieditor. Allele-specific DNA demethylation (ASD) refers to the targeted removal of DNA methylation in only one allele of a genomic locus. In this publication, we develop methods for ASD using an epieditor consisting of a sgRNA/dCas9 complex and the TET1 DNA demethyltransferase. We demonstrate the successful establishment of ASD in multiple genomic targets with high specificity, efficiency and stability. Targeted DNA demethylation subsequently led to a specific activation of the expression of the demethylated allele. This form of superspecific epigenome editing could find application in the treatment of imprinting diseases caused by incorrect genomic methylation.