It's life, Jim, but as we know it

Deconstructing Craig Venter's latest creation

Bill Hanage 21 October 2007

Stripped down: tiny bacteria recreated in the lab

Is this really synthetic life? Let’s leave that to the philosophers.

Bloody hell, Craig Venter has done it again. The man responsible for the first genome sequencing project, that of the bacteria Haemophilus influenzae, and a large part of the force behind the sequencing of the human genome – indeed, his genome, is now claiming to have created artificial life.

Venter is a divisive figure, acclaimed and condemned in roughly equal measure by the public, most of whom still have no idea who he is. A failing, one might say, it is his lifetime’s work to correct. Among scientists he attracts a somewhat different response. Yes, there are a fair few who will claim to detest him and his oh-so-flashy approach to science. But many wonder what the fuss is about.

Take the latest great Venter discovery. This morning, I awoke to discover that my paper was plastered with images of the man declaiming that he has created a new life form, together with an ‘exclusive’, not to mention fawning, interview (do read it, it’s hilarious: in the first paragraph the interviewer gets off on seeing a Petri dish).

OK, I think. New life form. Wow. Presumably it’s not a Pegasus or centaur or something similarly flashy and impossible. Maybe it’s something smaller, like a nematode, or a bacterium.

Bingo! It’s the last. Mycoplasma genitalium has the distinction of having the smallest genome we know about which is compatible with independent life. It is really tiny. Its genome is completely stripped down to the absolute minimum required to get along.

Hang on. It existed before, didn’t it? It even has a name. Well, yes. But what Venter has done is synthesise a modified M. genitalium genome, by removing those genes which are not absolutely essential and can be supplanted by growth media. Any biologist will know how easy it is to make a string of DNA. Generally you email a company and it arrives in the post a few days later, assuming they’re not on strike. But these are not long stretches of DNA. This is the major difference between the companies which produce DNA to order and Team Venter. Venter’s DNA is bigger. And here size certainly does matter. Even though the modified M genitalium has a tiny genome, it is still way larger than the stuff you order over the net.

But DNA on its own is not alive, so why the claims that this is a new synthetic organism? Well, apparently, if it is injected into a cell which was robbed of its own DNA, the replication machinery will kick off and start making copies of the stuff which was injected into it. Will this then be ‘synthetic’? Let’s leave that to the philosophers. I’m a bit underwhelmed by this. Had Venter developed a new enzyme say, which could break down plastic, I’d be well impressed. But all he seems to have done is make a really, really big DNA synthesiser to produce a really, really big chunk of DNA to order. In fact it is as if a person ordered “a set of car parts, assembled them into a car and then claimed to have invented the car”, as Nick Gay says in the Guardian. Nicely put.

Given that we have had Bacterial Artificial Chromosomes for yonks, I fail to see why this latest claim has generated any excitement at all. I’d say the first new life forms were in fact created decades ago by the first people to transform the bacterial lab strain E. coli with plasmids encoding functions which did not currently exist in nature. That was a bigger leap than the ability to make a vast DNA molecule, which even being generous, is a triumph of technology rather than understanding. More recently, some enterprising souls scared the living daylights out of many (including US Homeland Security) by ordering the necessaries to make a polio virus through the post.

So why is Venter there on the front page of the Guardian? I venture that the man is a masterful and inveterate self-publicist, with an eye for things other people are doing quietly out of the public eye and the ability to do something similar, in such a way that it attracts public attention. The human genome was largely sequenced by publicly funded organisations, but Venter has made sure that his is the name indelibly associated with it. I am not without admiration for the man: sometimes in science people have a habit of telling you what you can’t do rather than what you can. And it is darned refreshing to come across someone who tears up that rule book and chucks it overboard.

In fact, one could argue that Venter does something to redress one of the great injustices of science. The people we remember are usually those who come up with some new insight, a new way of looking at the world. Probably the best example in Venter’s own field of molecular biology would be Francis Crick. But such leaps are built on the technological advances of others, who get to share in the limelight rarely, if at all. In Venter we see this turned upside-down. The triumph of the lab technician told to sequence millions of base pairs who shrugs and gets on with it.

Except that this argument ignores the more queasy aspects of the genomic science he has done so much to bring into life, such as patenting genes (he is even suggesting patenting his ‘new’ organism). And I rather doubt that he would welcome the comparison above. Reading interviews with him like those in the Guardian, which are full of grandiose claims of what the new ‘advance’ heralds (most of which have only the faintest connection with it), modesty is not the first word that leaps to mind. And personally, for all the flood of data Venter and those like him have unleashed on the world, I’m still waiting for a Crick type figure to come along and make sense of it all.

Andrew Brown relates in The Darwin Wars that the late geneticist John Maynard Smith, when asked to comment on the then fashionable complexity theory of Stuart Kaufmann, is reputed to have replied “absolute fucking crap. But crap with good PR.” I don’t think that Venter’s work is crap. But I sure as hell recognise the advantage of a good PR machine. Clearly he does too.