A paper published in a recent edition Science magazine (VOL 325, pages 928 to 929) 21 August: focuses on progress in the area of Synthetic Biology. As the name implies, Synthetic Biology involves the generation of organisms that have not emerged from evolution but rather they are designed by scientists to achieve particular goals. There are two general approaches that can be involved in Synthetic Biology: in the first the DNA of an organism that has the potential to carry out a series of reactions that will give a new product that is useful or valuable, is trimmed down such that all functions that are not needed for the reactions of interest are removed from the organism. This mini gene set can be viewed as the result of an artificially accelerated process of evolution towards achieving a particular goal. The alternative is to design the organisms DNA content that is needed for a defined goal/product and then make a new organism de novo.
This may seem like an esoteric topic that is of interest scientists only, but my reason for blogging on it is because it could have very major consequences. One target that has been suggested for Synthetic Biology is to make a new organism that would be much more efficient than those that occur in nature, at fixing sunlight and hence providing a much needed new source of renewable energy. It is too early to enter into discussions on the relative merits of solar panels or organisms that trap the energy, but it does help formulate why this debate is important. The progress that has been made to date (particularly by Craig Venter who was a major force in sequencing the human genome) have shown that the DNA of an existing organism can be synthetically generated and introduced in to an envelope of a non-functioning organism to show that the synthetically generated organism can perform in the same way as the original natural organism. If that is possible then it is equally possible to make derivatives of this that have other sequences that maybe obtained from diverse organisms and to place them all in the same “envelope”. The task of getting the new DNA to divide was, as usual, more complex than had been anticipated originally but in the recent paper in Science, this problem has now been solved building on thousands of man years of research that leads to an understanding of how DNA divides in different organisms.
A robotic approach to generating novel DNA with improved functionality to perform a particular task has also been reported upon by George Church and his colleagues and the combination of the specific design of a DNA sequence, and clever mechanisms to have a high throughput of variations on what was available in nature and the possibility of getting this DNA to perform in a manner expected of any other organism has now all come together.
It should be recognised that the Synthetic Biology potential is dependent upon and follows intellectually from the understanding of nature that comes from the Systems Biology approach. It is also worthwhile pointing out that the research that has been performed to date has involved micro-organisms and that funding for research in microbiology has frequently been questioned by those who think that there is a very linear connection between research and the impact on human health which would lead to research being performed only on higher organisms or on human cells.
The promise and excitement of Synthetic Biology has to be balanced by a concern that has been well flagged in advance. Obviously, any time that a new organism is generated in a laboratory there are unknowns about the consequences if freely released into the environment. This is an extension of the standard discussion on the release of genetically modified organisms except that the scale of the unknown is significantly greater in Synthetic Biology as it’s not just one gene that is altered but the whole DNA content of an organism. The need to handle such organisms with great attention and to ensure that they do not enter in to the environment is obvious and must be firmly adhered to. The risk involved is not of the same order as the clearly defined inevitable negative consequences of nuclear radiation, but there is an unknown aspect in the new organisms that has to be recognised as a risk that has to be treated.
On balance therefore there is progress and a challenge simultaneously and of course that is what happens with all scientific advances.