Going down with the ship

jtotheizzoe:

Consider this a scientific NEWS FLASH.

Today in the journal Science, a very big claim was put forth about the central dogma of molecular biology. It has been accepted for a long time that the DNA that encodes genes is transcribed into RNA, and that RNA is read out into proteins. Occasionally, RNA can be read back into DNA, but other than that, this is the accepted order of, well, everything. 

The just-released research found that in human cells, there are quite a lot of RNA messages floating around (and proteins made from them) that don’t match the sequence of their DNA. The exact copying of RNA, while there is no specific reason it has to be that way, has been something that people have found no reason to doubt. Until now.

Specifically, the team from the University of Pennsylvania found that in almost a third of the genes in the samples studied, comprising over 10,000 examples, there were “RNA-DNA Differences” (RDDs). Some of the RDDs could have arisen from known RNA-editing enzymes, which have been known to exist for a while, but this doesn’t explain all of them. They also went to great care to make sure the techniques they used to sequence them weren’t to blame for the differences. Most importantly, the errors weren’t random … they were shared among different people studied, of all ages and backgrounds.

So the bottom line? Until we have reason to doubt their results, it appears that some mysterious process is causing these RDDs and providing an extra means for variation in proteins that could cause disease or just act slightly differently. If you thought the genome was complicated, looks like the transcriptome just opened Pandora’s box.

Here’s the paper (subsp. required, prolly). And Nature has a nice, long, detailed analysis. More to come as it develops …

(photo via flickr)

Just when we think we know everything…