from Wiktionary, Creative Commons Attribution/Share-Alike License.
- noun organic chemistry Either of two isomeric
hydroxymethylderivatives of cytosine, but especially 5-hydroxymethylcytosine which functions as a basein certain specialized DNAs
from Wiktionary, Creative Commons Attribution/Share-Alike License
This makes hydroxymethylcytosine the seventh modified base in eukaryotic DNA-unless there are some that I don't know about.
Now Kriaucionis and Heintz (2009) have re-discovered hydroxymethylcytosine in mammalian DNA.
And we aren't told that the authors actually cite earlier work showing the presence of hydroxymethylcytosine in mammalian DNA.