Synthetic Life is Real, Now What?

Craig Venter is most famous for his role in the race to complete the sequence of the human genome. He led the Celera team, the private effort run in parallel to the federally sponsored initiative.  Since that project he has expanded his list of accomplishments to include “metagenomics” in which his team sampled marine life in the Sargasso sea and redefined our understanding of biodiversity. His recent book, “Life at the Speed of Light” describes another area, his work on synthetic life.

Even the term “synthetic life” is likely to evoke controversy and concern. Where the work to sequence existing genomes studied “life as we know it”, synthetic life approaches biology as an engineering exercise, “life as it could be”.

Well before the work described here, genetic engineering has been in practice for decades and has contributed to life-saving capabilities. Genes from one organism have been moved into other organisms to simplify the production of drugs, for example insulin. More controversial has been the addition of bacterial genes to common crops to develop genetically modified organisms (GMOs).  While many genetic engineering strategies have been successful, many have also failed because the production of complex proteins requires more than just the gene encoding the protein.

Against this backdrop, we learn about the progress to develop synthetic life in which an entire genome has been engineered using building blocks from naturally existing organisms. Venter provides an accessible historical background in which he reviews work in the 1800s to synthesize biological molecules, beginning with urea. He moves through the Miller-Urey experiment that demonstrated how biological molecules, including amino acids, could develop from less complex precursors. Later experiments in which short nucleotide sequences were assembled in vitro and in which viruses were assembled through increasingly sophisticated technologies are described in a concise yet purposeful account that prepares the reader for the advances of the Venter group.

“Speed of Light” alternates between these historic accounts and the steady progress of Venter’s team to develop a fully synthetic life form. The first major milestone of his group was the complete synthesis of the genome of an existing bacterium, Mycoplasma mycoides, and the successful insertion of that genome into the cells of a related species in which their genomes had been removed.  The methods developed for this exercise enable researchers to ask scientifically important questions such as, “what are the minimal genes necessary for life?”. Venter provides multiple suggestions for the potential societal benefits that synthetic life could offer, including new ways to develop antibiotics, less resource-intensive approaches to industry and numerous others.

While he clearly falls into the “this is important and should be allowable” camp, Venter acknowledges the ethical concerns raised by synthetic life. He takes great pains to describe the ethics consultations that he funded to demonstrate that their work took appropriate precautions and carefully considered the ethics.  Synthetic life has significant national security implications and these are addressed briefly. Venter also touches on the philosophical and religious concerns of this work.

The concluding chapter seems to go in an unnecessary direction, with a discussion of extraterrestrial life and other speculative topics. There is some precedent for this, as Francis Crick addresses panspermia in his book “Life Itself”.

The content, structure and flow of “Speed of Light” are designed to position Venter’s controversial work in the historic continuum of contemporary biological research and biotechnology development rather than as something that he and his group did “because they could”.

Whether you think that pursuing synthetic life is right or wrong, there have been major advances in this field in the past five years and synthetic life is now a reality.  Venter’s book provides a clear technical and historical background to inform discussion and debate about the merits and risks of this technology.