Scientists have created a bacterium with the new smallest genome, containing a tiny 473 genes. Why is this important, and why should we care?
Researchers led by Craig Venter, perhaps best known for his contribution to the first sequencing of a human genome, have reported in Science that they have designed a 531 kilobase genome and introduced it into a synthetic bacterium. This is a huge reduction on the efforts in 2010 that produced a 1079 kb genome based on a Mycoplasma species. By way of comparison, the E. coli bacterial genome stands at over 4 Mb. This synthetic organism, dubbed JCV-syn3.0, has 149 genes whose function is reportedly unknown, a relatively high proportion.
On the face of it, this announcement may seem of little significance. After all, bacteria containing a synthetic genome have already been generated. Yes the size is considerably smaller, but with over 30% of genes present having an unknown function it gives the feeling of a job half done – how much further can the size be reduced once we know what role they play?
From another, ethical, perspective, is this ‘playing God’? As a Christian scientist, I feel reasonably comfortable in answering no, no more so than introducing ‘foreign’ DNA to lab strains of E. coli is. It may not be natural, but how natural are the all manner of modern dog breeds? Does it make it more okay just because the breeders are working with phenotype, the visible characteristics, rather than genotype? I think not. Science needs progression and if fiddling with synthetic genomes is that progression then this work should be applauded.
The real asset of this work is, in my opinion, its reflection of the fundamental importance that science plays in society. The opportunities to do something ‘just because’ – just because it’s interesting, just because you wonder if you can, just because it hasn’t been done before. It’s this viewpoint that to me sets science apart from other disciplines in that it keeps alive that curious inner child, the one who wants to ask the awkward questions that no one knows the answers to. So keep on going, Venter – I’ll be keeping a close eye on what you come up with next.