Numerous hurdles will confront synthetic biotechnology as the field expands. The creation of deadly super-bugs is an issue that has been raised since the first genetically engineered cells were created. We have avoided biological Armageddon up to now because the number and types of foreign genes inserted into cells and organisms has been carefully controlled—not by law, but through commercial expediency. The likelihood that such problems will arise in the future increases as researchers focus more on systems vs. single genes. The possibility becomes more real for completely artificial life, although Dr. Venter might disagree.
For the time being, synthetic biology faces more practical issues related to the constant evolution of cells and microorganisms. “It’s impossible to overlook this, to trust engineered living systems not to change over time,” says Dr. Campbell. “The big difference between bioengineering and electrical or mechanical engineering is organisms that undergo selection pressures, that continue to evolve even though that evolution is not part of our plan.”
Campbell cited a study that found that 10% of the time, knockout yeast strains spontaneously undergo gene deletions and duplications that were not designed into the organisms. Another paper found that the live BGC tuberculosis vaccine had been changing unnoticed since the 1960s. If simple organisms can evolve with no apparent evolutionary pressures, systems-wide manipulations may be prone to even greater diversity over time. The potential implications for cells and organisms used in biomanufacturing, particularly over many years, are worth considering.