ET Comment – Has Dr Venter created artificial life?
Announcing his ‘creation’ of the first synthetic life-form, geneticist Craig Venter declared on 20 May 2010: ‘This is the first synthetic cell that’s been made, and we call it synthetic because the cell is totally derived from a synthetic chromosome, made with four bottles of chemicals on a chemical synthesiser, starting with information in a computer’.
Without denying his scientific achievement, Dr Venter’s claim contains more spin than a tornado. Were it not for the fact that he details elsewhere what he actually has accomplished, his statement would be a total fib.
I wouldn’t start from here
Asked directions by a passing motorist, a country yokel scratched his head and answered, ‘If I were going there, I wouldn’t start from here’. Exactly. If Venter really had started with ‘information in a computer’ his experiment would have gone nowhere.
But, of course, he really started from an existing life form, the bacterium M. mycoides (GM12), whose DNA (‘genome’) sequence he simply recorded as ‘information in a computer’. Some genuinely synthetic segments were, however, added as ‘watermarks’ to distinguish the ‘synthetic’ genome from natural DNA.
This information was used to grow short lengths of the GM12 genome, which were then stitched together by inserting them into living yeast cells, where they recombined into complete chromosomes. (This was actually a three-stage process involving yeast cells and the bacterium E. coli).
Finally, after overcoming several difficulties, the ‘synthetic’ chromosome was transplanted into a different (though related) bacterium M. Capricolum, where it replaced that bacterium’s own DNA and gave rise to a self-replicating organism.
Tinkering with existing life-forms
This was a complex procedure requiring (1) the use of one natural bacterium as the source of the genetic information; (2) a yeast cell host to splice DNA fragments together into an ‘intermediate’ DNA; (3) multiplication of this DNA within a second live bacterium (E. coli); (4) a second yeast cell host to finalise the assembly of the ‘synthetic’ DNA; and (5) the transplantation of this DNA into its final host, a third live bacterium that closely resembles the original. This final host bacterium then reproduced – driven by its own cellular machinery that owed nothing to the implanted ‘synthetic’ DNA.
It is true that with successive generations this reproductive molecular machinery will eventually be built using proteins encoded by the new ‘synthetic’ DNA, but this involves no significant changes in the machinery itself.
It is rather like replacing the mechanical parts of a car one by one with equivalent components supplied by a different manufacturer. If the new parts were not functionally identical to those they replaced the car wouldn’t work, and nor would the bacteria in the experiment!
What Craig Venter has done, therefore, is not to create artificial life but to tinker with existing natural life. His work differs in no essential way from the genetic engineering that is already widely practised.
The origin of life
All this, of course, has a bearing on the origin of life – a subject I discuss at length (and in a layman-friendly manner) in my recent book Who made God? (see chapters 12-14). There is space here for just a single quote. With a modicum of prescience, I referred there to Craig Venter’s work thus:
‘Dr Venter’s chemicaltour de force demonstrates that to produce a meaningful string of DNA requires a lot of hard work by highly skilled and intelligent chemists. No one suggests that he and his team simply poured the necessary chemical ingredients into a cake mixer, set it on automatic and took a vacation. And that is just to copy an existing DNA molecule.
‘To create the first such molecule from scratch would, I suggest, have required an infinitely greater input of intelligence. It simply isn’t good enough to claim that the cake mixer actually will produce a “life-giving miracle” as long as you run it for a thousand million years or so before you bake the cake. Yet that, in effect, is what the atheist is compelled to claim’.
Professor Andrews’ book Who made God? Searching for a theory of everythingis published by EP Books (304 pp, hardback, £9.99) and is obtainable from bookshops and on-line.