What do you have in common with E. coli, a brachiosaurus, and Jesus? The language in which genetic code is written. There are only four letters: referred to as G, C, A, and T, corresponding to four different molecules known as nucleotides. Different combinations of these letters in strands of DNA lead to the wide variety of genomes that have existed in Earth's 3.5 billion year history of supporting life. These, and only these, letters have existed in the genetic code of everything that has ever lived...until now.
Scientists have created two new 'letters' for the genetic code: 'X' and 'Y', chemical compounds that do not exist in "nature". Think of the seemingly boundless diversity - the depths of which we haven't even begun to plumb - of forms of life that exist on Earth that use only 4 genetic letters in their genetic alphabet. Now, imagine the exponential increase in complexity, possibility, and diversity if extra letters are added to that alphabet. It's mind-blowing. It is postulated that the new additions could allow access to up to 200 amino acids (all proteins currently in nature are built using only 20!).
The scientists I refer to went even further: they constructed a synthetic strand of DNA using the new nucleotides and essentially created a new life form based on the code. That's right: the future is now, and alien forms of life are invading. In fact, we are creating them.
Cue the excitement and self-congratulatory remarks; cue the wonder at all that Science has achieved for us.... in the midst of the fanfare, I hear a deeply ominous strain. It alarms me that humans have taken it upon themselves to create new forms of life when they have such a poor and patchy understanding of existing forms; we don't even fully know why creatures sleep or dream or how memory works. As usual, technology far outstrips the ethical frameworks it necessitates...
My feelings on the discovery in short (too late)? Impressive. And scary.
The study, published in the journal Nature, is the first time that scientists have managed to produce a genetically modified microbe that is able to function and replicate with a different genetic code to the one that is thought to have existed ever since life first started to evolve on Earth more than 3.5 billion years ago.