Therapeutics. Epigenetic drugs may enable extremely precise gene- or gene domain–specific
targeting, possibly even reaching an unprecedented level of target specificity. However, the issue
of off-target effects may be completely different with methylome-targeted pharmacological agents.
This is because, to a first approximation (with a few exceptions in the immune system and germline),
every cell in a particular individual has the same genome. Different cell types have different
epigenomes (including different cytosine methylation patterns), but the underlying genome in