The Curious Chemical Biology of Cytosine: Deamination, Methylation and Oxidation as Modulators of Genomic Potential
Enzymes that chemically modify cytosine introduce a physiologically important layer of complexity to the genome, beyond that seen in the primary sequence. Numerous modifications beyond cytosine methylation are now coming to the fore, including cytosine deamination, oxidation and demethylation. As life demands variety and adaptability, many other “accessory” functions must also be hard-wired into the genome.
Expanding the DNA alphabet: 'Extra' DNA base found to be stable in mammals 2
Researchers from the University of Cambridge and the Babraham Institute have found that a naturally occurring modified DNA base appears to be stably incorporated in the DNA of many mammalian tissues, possibly representing an expansion of the functional DNA alphabet.
DNAmod: the DNA modification database 3
DNAmod is an open-source database (http://dnamod.hoffmanlab.org) that catalogues DNA modifications and provides a single source to learn about their properties. DNAmod provides a web interface to easily browse and search through its modifications. The database annotates the chemical properties and structures of all curated modified DNA bases, and a much larger list of candidate chemical entities