Team:KULeuven/Ethics/Concerns/Defining

Synthetic biology: concerns and issues
What is synthetic biology? How different is it from recombinant technology? Can it already be safely implemented? And if not, which extra precautions have to be taken into account? In this chapter, we will try to answer these questions. Furthermore, our attempt will provoke ethical questions and questions about issues of human practice.

Defining Synthetic Biology
Synthetic biology is one of the most audacious and controversial scientific ideas of the twenty-first century. The rise of synthetic biology brought a whole shift within the biological sciences. Scientists no longer confine themselves to the reading of DNA, but instead start to create new artificial DNA-codes. Tom Knight, research scientist at MIT, describes this difference as following. "A biologist goes into the lab, studies a system and finds that it is far more complex than anyone suspected. He’s delighted, he can spend a lot of time exploring that complexity and writing papers about it. An engineer goes into the lab and makes the same finding. His response is: “How can I get rid of this?” (1)." In “Leven Maken, Maatschappelijke reflectie op de opkomst van synthetische biologie” (2),the approaches towards synthetic biology are divided into two broad classes. On the one hand there is the bottom-up approach and on the other one there is the top-down point of view.

Bottom-up approach
It is possible to take any part of life, torn apart into pieces, and then creating more and more complex systems from them. This methodology is called the bottom-up approach. The BioBrick initiative, and everything that comes with it, is clearly an example of this approach. As the iGEM contest is about using these BioBricks, this bottom-up approach will be our major focus in the rest of this discussion.

Top-down approach
The particular vision of hierarchical biological reductionists assume that everything in life, especially the living nature, can be reduced to physical processes, which, on their turn, can be described mathematically. This way, it tries to tear apart different parts of nature, which can then be torn further apart, and torn apart and so on, until one reaches the molecular, physical or mathematical level. One of the examples of this approach is the minimal genome project carried out by Craig Venter and others (3). One of Venter’s studies focuses on building a sort of cellular chassis. They want to create an entire genome that forms a base for simple cellular life. A cell with a minimal genome would be an excellent scaffolding for further study. By reducing the complexity of biological systems and processes in cells, one can make cellular pathways more predictable and better controllable.

Another example of top-down synthetic biology was something that catches the eye: synthetic DNA analogs. The Herdewijn research group at the Katholieke Universiteit Leuven for instance, is very much involved in this. They are trying to find the possibilities of creating a parallel nature out of synthetic DNA. This synthetic DNA is different from the commonly known DNA forms in that it uses the same bases, but a different backbone. Mostly this is done by changing the hexofuranose sugar to another kind of ring or ring-like structure. Then, this material is tested for its ability to use normal DNA polymerase (4). They are also looking for modified polymerases that can specifically read their synthetic kind of DNA.