Why Do Humans Have Less DNA Than This Flower?
More DNA means more complexity, right? Scientists say not necessarily! Why is that the case?
That we only use about 10 percent of our brain is a myth that's been thoroughly busted, but here's one that stands up: On average, humans only use about 8 percent of our DNA.
As Julian Huguet explains in this DNews episode, researchers in the United States recently designed a synthetic cell that's able to survive and replicate with the absolute minimum number of genes. The tiny li'l feller -- "minimal bacterial cell Syn3.0" in official parlance -- is believed to be the smallest life form on the planet, DNA-wise.
The research, published in the journal Science, underlines a fact long known to biologists: Organisms can live and replicate without all of their DNA. In fact, we Earth creatures can get by without massive chunks of it.
Some interesting numbers: All the cells in your body have 23 pairs of long DNA sequences called chromosomes. Those strands are made up of about 3 billion "base pairs" -- the building blocks of DNA. More base pairs doesn't necessarily mean a more complex organism, however. The flower Paris japonica, for instance, has more than 150 billion base pairs.
It's not the size of the DNA, it's how you use it. Much of the DNA information we're carrying around, on the cellular level, is leftover baggage from the process of evolution. According to some estimates, around 92 percent of the human genome is essentially unused junk DNA.
Of the 8 percent we do use, 1 percent is coding proteins, and 7 percent is telling that first 1 percent what to do and when.
These aren't consensus numbers, mind you, and the math gets weird. Depending on how you define your terms, some researchers believe that as much as 80 percent of our DNA may serve some kind of purpose. But even going that direction, around 60 million base pairs appear to be just tagging along for the evolutionary ride.
So the next time mom suggests you're not living up to your potential, remind her that she's finding fault on the cellular level, and that's just not fair.
Discovery News: World's Oldest Known DNA Discovered