“Humans are almost unimaginably complex, but have scarcely more genes than a fruitfly or a worm. The human genome comprises about 99% ‘junk DNA’ — genetic code that is not used to make the protein building blocks of life. Junk DNA accumulates in organisms’ genomes simply because it is good at accumulating.Genes that do code for proteins may recruit some or all of this junk DNA to regulate when, where and how much they are expressed. Something has to instruct genes to team up to produce complex structures such as hearts and kidneys.
Regulation is how we can have over 98.5% similarity to chimpanzees in the sequences of our coding genes, yet differ so utterly from them.
The huge quantity of junk DNA in the genomes of most complex organisms may act as a vast digital regulatory mechanism.
The emergence of digital regulation derived from unused stretches of junk DNA may have precipitated the transition from single cells to complex multicellular organisms.”
Rise of the digital machine Mark Pagel
Nature 452, 699 (10 April 2008) | doi:10.1038/452699a; Published online 9 April 2008