Our DNA is the blueprint to "building" our bodies and adjustments to the blueprint can be made by epigenetic marks. These marks are DNA modifications that do not change the underlying genetic code but include extra information on top of it, which can eventually be inherited. Epigenetic marks regulate gene expression and suppress transposons (also known as "jumping genes") that can threaten the integrity of one's genome. Dr. Irina Arkhipova, senior scientists in the Marine Biological Laboratory's Josephine Bay Paul Center, shares a bacteria named bdelloid rotifers, found in small freshwater animals, has been discovered to contain a novel epigenetic mark. This was measured to have happened about sixty million years ago. "This discovery marks the first time that a horizontally transferred gene has been shown to reshape the gene regulatory system in a eukaryote" says Kenney, author of the article. According to Dr. Arkhipova, horizontally transferred genes are known to preferentially be operational genes and not regulatory. In my opinion, this event is fascinating- how a single, horizontally transferred gene can form a whole new regulatory system, when the existing regulatory systems are already complicated. A piece of bacterial DNA and eukaryotic DNA become joined in the bdelloid rotifers' genome and they form a functional enzyme.