Fears are generally excessive and misplaced. But it is up to us to explain this and why, not simply to carry on and ignore the people who ‘don’t get it’. This is not the beginning of the opportunities to make new and terribly dangerous bacteria. This was possible (and has been done) long ago by microbiologists working for multiple governments behind closed doors – and never has so much work been done that could underpin people doing terrible things than in recent years in the name of ‘biodefense’. Whatever horrible thing you might like to imagine as a plot for a thriller has quite probably already been done somewhere, if it is possible to do it. The people who have done this, and who might do so – are not the ‘synthetic biologists’. And, the only reassuring thing about all of this is that nobody has used these things – except to horribly contaminate a small Scottish island with anthrax.
It is true that the field is lacking in useful guidelines in some areas. The existing definitions of what is and what is not an organism with pathogenic potential to people is somewhat more fuzzy than most people will imagine. It is also true that ethical and safe practices seem to differ substantially between institutions, countries, and companies –some of which probably far exceed the standard in academia, and some of which do not. These things and others need to be addressed, though the hazard and risks are lower than what I have just said might make some people think.
The most reassuring thing about synthetic biology is the fact that it is design-led and inherently predictive as to outcome. In the past, many studies have been performed in which one or more random changes have been made to remove genes, change genes, and variously change biological systems –without the slightest clue about what the consequences would be. The use of this type of screening experiment has been wide-spread and addressed many different biological processes and organisms, and perhaps surprisingly nothing has gone horribly wrong (if we ignore the cancer researchers who mutated themselves and got cancer, and other local casualties).
In bioprocessing and other areas that used bacteria people would simply look for a strain that did the closest thing to what was wanted that they could find. The background knowledge of its other properties, gene content, behaviours, and the risks that it might present were close to none. Now, we work with highly characterized strains, for which we have knowledge on all of the genes that are present, and can look for and when useful specifically remove genes that make them safer than anything similar that occurs naturally. This increasing background knowledge should not be a source of complacency, because ‘reduced risk’ is not necessarily ‘no risk’ – but it is a substantial improvement on what has been done for many decades previously.
In synthetic biology the changes are targeted, specific, and deliberate. They are based upon knowledge-based design in which the components used are applied to result in a clearly intended function, and this is subsequently confirmed – and intended outcomes or unintended consequences are identified. There are not mixtures of hundreds or thousands of unknown changes to be assessed by a range of relevant and not relevant tests for whatever might have happened (like before). Now there are a few deliberate changes, which are tested with highly relevant assays. This is inherently a much more rational and safer approach.
Also, the synthetic biology process, especially using the ‘synthetic systems biology’ approach has further increased safety consequences because multiple changes are being made that combine to take an organism further and further away from what nature and evolution has created as the most viable and survivable biological solution. What an industrial or other designed solution seeks to develop is a ‘biological component’ for a process with a number of process-determined properties. Changing just one aspect of the central behaviour and metabolism of an organism is likely to reduce its fitness in other contexts – although with single or closely clustered changed this cannot be assumed. But, when it involves multiple changes the cumulative effect will almost inevitably be a progressively less and less naturally fit, and less and less risky in all ways – including within the wider natural environment, in which it would be unlikely to prosper and survive. Life has already generated the optimum solutions – in the wider world the synthetic organisms would be uncompetitive and very unlikely succeed.
This is not to say that it would not be possible to specifically engineer something with increased fitness potential. But this is not the typical synthetic biology objective, and should be considered (and if necessary) regulated as a special case if it was appropriate (for example, a mosquito engineered to compete with the malaria transmitting species – which is not what we do). Typically, the synthetic biology objective is to create a strain of something which makes a lot of something useful and valuable, which past a certain level is usually poisonous to the cell making it, and the better it gets at doing this engineered thing – the more unfit for normal life it becomes.