Junk DNA Is Useless, Says Carnivorous Plant

We've been told time and time again how vital our DNA is, yet new evidence may just showcase how insignificant a vast majority of it is, thanks to one carnivorous plant.

Only around two percent of our DNA consists of so-called "genes" which code proteins and other essential processes for our biological livelihood. The rest of our DNA is dubbed "junk" - useless bits of coding that serve no purpose to the naked eye. Scientists sequencing the bladderwort plant, however, found that the plant had eliminated most of this junk DNA, keeping only what's necessary.

"The big story is that only 3 percent of the bladderwort's genetic material is so-called 'junk' DNA," study co-author Victor Albert from the University of Buffalo in New York said.

"Somehow, this plant has purged most of what makes up plant genomes. What that says is that you can have a perfectly good multicellular plant with lots of different cells, organs, tissue types and flowers, and you can do it without the junk. Junk is not needed."

The bladderwort plant genome is the smallest ever sequenced from a complex, multicellular plant, with only around 40 million base pairs. Other tiny plants such as the lily can have up to 80 billion base pairs. The bladderwort's only-what's-necessary attitude sheds even more light on the uselessness of certain parts of DNA.

Scientists are still puzzled, however, about the role of junk DNA. While some theorize that evolutionary stresses might have made the bladderwort shed useless DNA, there's still the question of what exactly is junk DNA's role in the genome. 

"Nobody's really known what junk DNA does or doesn't do," Albert told LiveScience.

"At least for a plant, junk DNA really is just junk - it's not required."

You can read the full published study in the journal Nature.