It is an iconic scene in the original Jurassic Park film in which Jeff Goldblum’s character, Ian Malcolm, is having dinner with the park’s creator, John Hammond (actor Richard Attenborough). As Hammond is bragging about his team’s success in building a dinosaur from the bottom up, Malcolm stops him with his provocative statement, “Yeah, but your scientists were so preoccupied with whether or not they could, they didn’t stop to think if they should.” In origin of life research, this is the ethical question of the day: should we create life in the lab? However, before we can even ask the question “should we” we have to ask the question “can we?” Researchers have been hard at work in their attempt to create life in the lab ever since the Miller-Urey experiment in the 1950s, and they have had some amazing successes. This article is not an attempt to put statistical probabilities on the possibility of science creating life, nor to provide an in-depth scientific analysis of the biochemistry involved in the process. Rather my goal is to take a birds-eye-view of what steps are necessary to create life, its inherent problems, and if science is successful in its venture, what conclusions can be drawn.
At this point, science is far from building a T-Rex. And since building life is such a monumental task, researchers have focused on what is needed to build the simplest life form: the individual cell. However, if science has taught us anything over the past 60 years, building a single cell is no simple task either. So, what is all needed to build a functioning cell? While there is a full laundry list of parts and systems necessary to build a simple cell, there are four primary things which are necessary for life:
- Macromolecules such as proteins, RNA and DNA.
- A boundary membrane to encapsulate these macromolecules.
- Metabolic processes.
- Replication.
For now, we will ignore the origin of the building blocks of life (amino acids, nucleobases, sugars, and fatty acids) and move on to where science is in assembling these building blocks into a macromolecule such as a protein. To date, science has accomplished much. “Synthetic biologists have been able to modify separately the genetic code in E. coli, yeast, and mammal cells so that more than thirty non-natural amino acids are incorporated into proteins produced by the cell’s machinery.”[1] This means that researchers are now able to produce never before existing proteins “with chemical capabilities that extend well beyond what is currently possible with the twenty naturally occurring amino acids.”[2] Chemistry professor, Floyd Romesberg gives an excellent TED Talk on expanding the genetic code. And if researchers can make new proteins, what are the challenges to making a boundary membrane that can isolate the biomolecules and their functions from the outside environment?
Without a boundary membrane, life could not keep its chemical makeup separate from its surroundings, and life could not exist. A cell membrane is composed of a single phospholipid bilayer (unilamellar). Membrane biophysicists have succeeded in creating cell membrane-like vesicles (liposomes) with an internal cavity. Origin of life researcher, Jack Szostak, and his team have even succeeded in encapsulating a protein inside such a vesicle.[3] However, there are a few problems. First, apart from an already existing cell membrane, purified phospholipids do not spontaneously form a single phospholipid bilayer. Rather, they form multiple bilayer sheets (multilamellar) or spherical structures which resemble an onion. This means that researchers must force purified phospholipids to do what they do not do naturally, and “under a unique set of conditions”[4] (fatty acid concentrations and water temperature, pH and salt content). And once produced, they do not last. “Currently, no method has been developed that can form stable, long-lasting vesicles.”[5] So now that researchers have been successful in manufacturing a boundary membrane and encapsulating a biomolecule, what about the metabolic functions which drive the cells processes.
Life cannot exist without metabolic processes that convert organic materials into usable energy, assist in the transport of biomolecules and to respond to their environment, to name a few. Once again, researchers have had some success in hijacking existing metabolic processes and force them to produce a desired result. Once such example is a process which produces C5 to C8 aliphatic alcohols, which are more like gasoline, to overcome the shortcomings of ethanol (which is a C2 alcohol). “This work opens up the possibility of using bioengineering of metabolic pathways in microbes as a way to generate alternative sources of energy.”[6] So now that we have macromolecules, a boundary membrane, and metabolic processes, all that is left is the problem of replication.
Like the others, replication is critical to life. If there is no replication, there is no passing on of genetic material. Researchers have not had near the success in this category as they have had with the others, mostly just hypothesizing about the origin of the first self-replicating molecules. However, researchers have succeeded in creating RNA molecules which can copy other RNA molecules. Unfortunately, these RNAs are incapable of duplicating themselves.[7]
The scientific advance of the past sixty years has been nothing short of spectacular, from the manufacture of synthetic human insulin which has saved the lives of millions, to the discovery of oil-eating bacteria that have the potential to clean up oil spills. However, how close is science to creating life in the lab? In some ways, they have been successful in the fact that they have created life forms that did not exist previously. But this is a far cry from creating life from scratch. Biochemist, Fazale Rana, explains, “when [they] succeed, they will not have made life from ‘scratch.’ Instead, they will have merely remodeled an existing life-form to generate a novel creature.”[8] So, what does all of this scientific advance show us? First, our list for life was highly abbreviated; we did not even discuss the necessity of enzymes, homochirality and the permeability of the cell membrane to name a few. In addition, all of these systems are interdependent, creating the chicken and egg phenomenon; all are needed simultaneously for life to exist. Therefore, the problems associated with creating life from scratch are far more complex than what I have shown here.
What I have shown is amazing progress, conducted by thousands of brilliant scientists at the top of their fields building progressively on the successes of those prior to them. This advance occurred via sixty-plus years of long hours of painstaking lab work, using the most advanced technology of our day, with nearly unlimited monetary resources. And yet, we have barely put a dent in what it takes to create life.
But even if we do succeed in creating life, we will simply have proven the overwhelming intelligence that is required. And if intelligence is required now, why would we ever conclude it was not required the first time life appeared on planet earth? Why would we conclude that a mindless process could accomplish such a feat? Is such a conclusion even logical?
[1] Fazale Rana, Creating Life in the Lab (Grand Rapids, MI: Baker Books 2011), 62.
[2] Lartigue et al., “Creation of a Bacterial Cell.”
[4] Fazale Rana, The Cell’s Design: How Chemistry Reveals the Creator’s Artistry (Grand Rapids: Baker Books, 2008), 229.
[5] Rana, Creating Life, 76.
[6] Ibid., 56.
[7] https://www.sciencemag.org/news/2016/08/newly-made-rna-strand-bolsters-ideas-about-how-life-earth-began
[8] Rana, Creating Life, 46.
Dan Hoelscher