Over the last couple of days, you might have heard about the "duon" — a "second" genetic code that's being hyped as a radical new "breakthrough" in science.
Based solely on the number of words I've put in quotations here, you can probably guess that the actual news doesn't really match the hype.
I'm going to keep this as short as possible, mainly because, from what I can tell, this duon news doesn't deserve a whole lot of your time and attention. But, basically, it boils down to this: Your DNA contains the information that creates proteins. It also contains the information that regulates which genes get expressed and how proteins get made. A recent press release, announcing the findings of an article published in the journal Science, has presented this dual function as something mind-blowingly new. It's not. That doesn't mean there's nothing new being presented in the paper. It's just that the stuff that's new isn't really out-of-this-world-omg-everything-changes, nor is what's actually new the same as the stuff being presented as new. Alex Riley of Bacteria to Bonobos explains:
Researchers from the University of Washington have found that these regulatory regions are commonly found within the protein-coding regions themselves. It was previously believed that these two regions of DNA – regulatory and protein-coding – were spatially separated: transcription factors bound to regions upstream of the protein-coding sequence (known as an “exon”). Imagine a length of rope with bands of blue and yellow. The different colours are analogous to this simplified arrangement of regulatory sequences and axons: Blue, yellow, yellow, yellow = regulatory region, protein-coding, protein-coding, protein-coding This compartmentalised arrangement of regulatory region followed by exons (as the image above shows) was what I was taught as an undergraduate.
...Even the finding that these regulatory regions are embedded within protein-coding sequences is nothing new; they have been discovered in several studies since 1995. The main conclusions of this new study by Dr. John Stamatoyannopoulos and his colleagues is that these regions are more pervasively contained within coding-sequences than previously believed – 87% of genes (from the 81 cell types investigated) contained them. (And, perhaps they have coined the term “duons” for these genes – I’m not sure.)
Essentially, this study adds some color to a painting we've already seen. But the press release is trying to sell it as the discovery of an entirely new painting. And that is annoying a lot of scientists and science writers who cover the field of genetics regularly.
You can read more at Emily Willingham's Forbes blog (be sure to check out the comments, as well).