Bioengineering Life – A Human Endeavor
Daniel Sprockett (formerly of ‘Just 10% Human’) broadens his scope to look at scientific issues and stories more generally in ‘Shot of Science.’ This week, he shows us bioengineering is far from a modern phenomena. In fact, we’ve been doing it for 12,000 years.
This is because Louise is the first human being ever born using in vitro fertilization, or IVF. Australia’s first IVF baby, Candice Reed, recently turned 33. Since their births, IVF has helped millions of infertile couples conceive, with over 100,000 babies born using IVF in Australia and New Zealand alone. Louise and Candice’s milestone birthdays often reason for religious groups to renew their controversial opposition to IVF and other modern family-planning methods, with their most common rallying cry being that such techniques are “playing god.”
Personally, I’ve never really understood this denouncement. The people that claim that medical techniques like IVF are “playing god” are often the same people that strive to live their life based on their god’s example, right? So in what sense is “playing god” negative? Since I am not religious myself, I won’t belabor this point. But with the frequency that this criticism is lobbed at scientific research areas ranging from cosmology to molecular biology, surely someone among the devout has noticed this incongruity.
In my own field, I most often hear that scientists are “playing god” when we use techniques to bioengineer an organism. In its essence though, bioengineering is simply anything that influences life that is independent of natural selection or stochastic processes. Granted, I’ve seen the same science-fiction movies that you have, so I understand why the term “bioengineering” might have an odious ring to it. (Jurassic Park, anyone? Frankenstein’s monster? Or perhaps even…Icarus?) But the truth is, humans have been bioengineering life to suite their needs ever since the Neolithic Revolution began around 12,000 years ago. By simply regulating which plants or animals are allowed to contribute to future generations, Neolithic bioengineers have drastically changed the forms and functions of many of our most familiar plants and animals.
For example, rudimentary artificial selection has shaped a single ancestral plant species, Brassica oleracea, into the well-know vegetables broccoli, cauliflower, cabbage, kale, Brussels sprouts, and kohlrabi. The wild common ancestor of all of these was probably first domesticated by the ancient Greeks. Sweet corn is another great example. Teosinte, corn’s grassy ancestor, still grows wild in parts of Central America. But in its non-domesticated state, corn more closely resembles wheat then the sweet, juicy, golden kernels that you can buy at The Rocks Market in Sydney.
If the genetics of our modern crops have been rough-hewn from their wild ancestors through artificial selection, the tools of modern molecular biology are more akin to a surgeon’s scalpel. Hundreds of scientists have contributed to this field, but no one has wielded that scalpel more deftly than Craig Venter.
Craig Venter first rose to prominence in 1992, when he founded The Institute for Genomic Research (TIGR), which later became part of the J. Craig Venter Institute (JCVI). Just three years into its existence, TIGR made headlines by becoming the first research group to sequence the complete genome of a free-living organism, the bacterium Haemophilus influenza. Then in 1998, Venter founded Celera Genomics, a privately held company that worked in conjunction with the publicly funded Human Genome Project to publish the first (more-or-less) complete sequence of the human genome in 2001.
Since that time, Venter and his team have continued to make enormous strides in bioengineering, and shown no signs of slowing down. They announced in 2008 that they had assembled the 582,970 base pair long genome of the bacterium Mycoplasma genitalium, built from artificially synthesized DNA. That might sound like a big genome, but M. genitalium was chosen specifically because it has the smallest genome ever found in a bacterium. The group took the next leap just two years later, when they successfully inserted an artificial synthetic genome of the bacterial species Mycoplasma mycoides (nearly twice of the size of M. genitalium) into a cell from the closely related species Mycoplasma capricolum that had had its genome deleted. This hybrid cell was considered by some to be the world’s first artificial life, but others contend that it doesn’t count, as the genome of the donor species already exists in nature. This isn’t exactly true, since the inserted artificial genome also included some added distinguishing “watermarks,” including the names of investigators, a web address, and a few famous quotations, including one from Nobel Prize winning physicist, Richard Feynman:
What I cannot build, I cannot understand.
This controversy is all a matter of semantics in my view, but the point will soon be moot anyway, since Venter stands poised to announce his latest advancement: a bacterial cell controlled by a completely artificial genome of human design that they’re calling Mycoplasma laboratorium. Just last week, Venter told Business Week:
We’re trying to design a basic life form—the minimal criteria for life. It’s very hard to do it because roughly 10 percent of the genes are of completely unknown function. All we know is if we take them out of the cell, the cell dies. So we’re dealing with the limitations of biology. If we start with this minimal synthetic cell that we’re designing and building now, you could recapitulate all biology by adding components to that cell. In theory, we could eventually get to humans by adding enough components to that genome.
Going after a stripped-down version of a genome has many advantages. First of all, it represents the simplest version of a very complex system. This can decrease the amount of resources needed to studying the system in general. Secondly, eliminating genes with unknown or incompletely described functions reduces the chance that the cell will behave in unanticipated (and potentially dangerous) ways when they are transferred to new environments. If the new artificial bacterium ever escaped the lab, it would likely be quickly degraded by environmental microbes. These microbes have had the advantage of a few billion years of evolution by natural selection, after all.
Finally, and most importantly, the minimal genome provides us a stripped down chassis to customise. Researchers could design genetic modules to be inserted into the genome, giving it expanded functionality. A recent profile of Venter in the New York Times suggests that his latest business endeavor, Synthetic Genomes Inc. (SGI), has been focused on engineering algae that can produce biofuels from carbon captured from traditional industrial sources:
To that end, SGI had recently purchased an 81-acre parcel of land about 150 miles away, right beside the Salton Sea, where it can begin to cultivate its most successful strains (of algae). The site, he added, also sits near a geothermal power plant, which doesn’t burn fossil fuels but does release carbon dioxide from underground. Venter was already in discussion with the plant’s owner to divert its carbon emissions into the algae. It was possible that, within months, his algae would be turning pollution into food and oil.
The burgeoning field of synthetic biology holds vast amount of promise, and will open up a myriad of potential medicinal, environmental, and industrial applications. Concerns about its safety, ethics, and regulation need to be addressed through rational discourse and an appreciation for where each new advancements stands in the larger arc of biological research and scientific advancement. Bioengineering is nothing new – we’ve just recently developed the tools to become much better at it.
Daniel Sprockett is a researcher at the Case Western Reserve University School of Medicine in Cleveland, Ohio. He currently resides in Double Bay with his wife, Andrea, while she completes a Master’s of International Public Health at the University of Sydney. Dan will return to the United States in September, when he begins his PhD in Microbiology and Immunology at Stanford University.
Read more of Daniel’s articles here.
(Top image from Chase Clark)