"Methylated DNA" refers to DNA molecules that have undergone a chemical modification known as DNA methylation. In this process, a methyl group is added to the cytosine base of a DNA molecule, usually occurring at specific sites within the DNA sequence called CpG dinucleotides. DNA methylation is an essential epigenetic mechanism that can regulate gene expression and chromatin structure. Methylated DNA often leads to gene silencing, as it can inhibit the binding of transcription factors and other proteins required for gene activation. This modification is crucial for normal development, cellular differentiation, and the maintenance of cell identity, and it also plays a role in various diseases and biological processes.
