Dr. Venter is a biology guru. Not only his team, together with the US government, was the first to sequence the human genome, but (in 2010) they had managed to create what had been called the first synthetic life form. At the time, the visionary team had assembled a synthetic chromosome (called JCVI-syn1.0) from scratch based on the organism Mycoplasma mycoides and transplanted it into the receptive cellular environment of the organism Mycoplasma capricolum, forcing it to change into a new species controlled only by the synthetic genome and able to self-replicate. Venter had described it as the first self-replicating species on the planet whose parents is a computer.
During their experiments, one big question had surfaced: how much of the genes of an organism are really necessary for life? What would a minimal genome, stripped away of all his non-strictly necessary components look like? Venter and colleagues had no doubt: this was to be their next challenge.
In the past few years, the researchers used their in-house technique for whole-genome design and synthesis to reduce the JCVI-syn1.0 initial genome from 1079 to 531 kilobases, corresponding to only 473 genes (and now called JCVI-syn3.0). When the JCVI-syn3.0 was transplanted into a viable cell, it produced polymorphic colonies similar to the one of the original JCVI-syn1.0 genome.
During their effort, the scientists discovered something important: those 473 genes are not all essential, but some can be classified as quasi-essential. These last ones are not critical for viability, but nonetheless need to be included in the genome to allow for a robust growth of the organism: a trade-off between genome size and growth rate. The organism also contains 149 genes whose functions remain unknown.
This makes for an incredible advancement in the understanding of how life works at the molecular level. The Venter team has once again managed to shake the pillars of biology, and thanks to their work, the world is now gifted with a novel platform that will be useful to continue the investigation of the core functions of life and the exploration of whole-genome design.
1. Hutchison, C. A. et al. Design and synthesis of a minimal bacterial genome. Science 351, aad6253-aad6253 (2016).
2. Gibson, D. G. et al. Creation of a Bacterial Cell Controlled by a Chemically Synthesized Genome. Science 329, 52-56 (2010).
3. Venter, J. C. The Sequence of the Human Genome. Science 291, 1304-1351 (2001).