i-908ee2a82946f9a9f0e80ea06b5285f6-XNA-thumb-300x351-44255.pngAn interesting paper in BioEssays last month looks at the potential future of xenobiology, totally orthologous biological systems made out of synthetic nucleotide and amino acid bases, new cells that use XNA instead of DNA. The author, Markus Schmidt, argues that while the design of such systems current poses a difficult technological challenge to researchers in synthetic biology, that xenobiological systems will enable a "genetic firewall" between natural and designed organisms, creating a built-in measure of biosafety.

This is something I've argued for before, in reference to creating new genetic reading systems for cells, so that even if DNA was passed between organisms, a natural organism would read the synthetic gene as genetic gibberish. Schmidt takes the discussion much further, pointing out that even though there will be a genetic firewall, synthetic organisms will likely be able to still interact with natural organisms at a chemical and ecosystem level, passing chemicals back and forth in the environment. This kind of interaction is something that has to be thoroughly considered in the design of new biologies, and may turn out to be difficult to predict in practice.

New biologies will also likely have a huge impact on how we think about life. Schmidt ends his essay on an interesting and complicated note--how will designed xenobiology affect our worldview, our notion of life?

The history of science shows several changes to our worldviews, altering our folk-based narratives to more scientifically inspired (semi-)rational approaches. In this context, science has inflicted a series of disappointments and disillusions to our folk-based beliefs, such as: the earth is not the center of the Universe, men and apes share the same ancestors, or that emotions and thinking is correlated to a neurological substrate. The promoters of these ideas were often attacked by those trying to keep the intellectual status quo. Xenobiology could easily trigger the next paradigm change in the way we understand nature and life. Just as the Earth lost its place as the center of the universe, or men lost its unique status in the animal world, our natural world could lose its unique status as being synonymous with ''life.'' But as with all other paradigm changes, concepts that better explain the world around us cannot be ignored for long.

If a new genetic paradigm built out of synthetic chemicals instead of naturally occurring DNA bases was designed, would it affect your sense of self? DNA's centrality to living systems on Earth is by no means a sign that DNA is the only genetic molecule that life can be based on, or that there even needs to be a genetic molecule at all. Manipulating and designing new kinds living systems will tell us a lot about what it means for something to be alive, but it shouldn't make life on Earth any less important or fascinating to us as people.

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New life being being made with XNA would cause no greater damage to my sense of self than a computer being able to beat me at chess (or its being able to beat grand champions etc).

Thanks for the heads up, it should work now!

And that's a really interesting analogy that I hadn't really thought about in this context. I agree that computers doing "human things" doesn't make people less human, and in the same vein that having something we make be "alive" doesn't make us less alive. The tensions and interactions between people, computers, and now synthetic biology is really interesting and important for a historical and a design perspective on new technologies.

I love the modified version of Haeckel's tree!
While Schmidt rightfully notes that science has dispelled a lot of illusions of grandeur that humans had before, it also seems to feed our egos (a lot).
We bend environments to our will, we develop spacecraft to travel between the stars and now we might even spark the creation of new life. One could argue that we are becoming more and more like the gods of ancient myths, thanks to science.

In regards to the 'genetic firewall', I must qoute the immortal Ian Malcom: Life finds a way.

Why not use the same DNA and amino acids, but in the opposite chirality? We would theoretically be able to make an exact parallel without the possibility of genetic interaction. Do you know if anyone has tried this?

As a side note, it might be cool to be able to call your experiment Sinister Life, although that might lead into some unfortunate PR problems.

XNA life would not affect my sense of self-identity at all. However, if XNA life proved more robust than conventional DNA life, I would be interested in using some kind of XNA stem cell technology to transition my body from DNA based cells to XNA based ones, providing the transition does not seriously alter my memories and emotions.

I think many people will be interested in such personal upgrades if it offers greater robustness, resistance to disease, not to mention elimination of aging. I think this transition process would be a big business opportunity. We need this sort of think to live off world anyways (once we get out into space).

... and may turn out to be difficult to predict in practice.

If there's some sort of blog understatement competition going on, Christina Agapakis just won it.

kurt9 @ # 6: ... providing the transition does not seriously alter my memories and emotions.

And how could it not? Let's imagine-for-sake-of-discussion that every tissue and organ is toned up flawlessly by XNACorp products: glands will pump out more hormones and receptors will react to them more, guaranteed to give anyone a memorable internal roller-coaster ride. So the CyborgCo autodoc will have to program your endocrine system until you can manage it autonomously, and that dumps you right back into what you (say you) want to avoid.

By Pierce R. Butler (not verified) on 20 Apr 2010 #permalink

If a new genetic paradigm built out of synthetic chemicals instead of naturally occurring DNA bases was designed, would it affect your sense of self?

It would intensify my self-image as a member of a species likely to be extinct, or close to it, in a few more generations. Otherwise, awesome dude!

By Pierce R. Butler (not verified) on 20 Apr 2010 #permalink

The development of synthetic living organisms is hardly a problem for me; I am the result of a great deal of interaction between the human and non-human, and for that matter, the inorganic world. My one concern is that, like the physicists who built and fired the first fission bomb, we are performing experiments in a knowledge vacuum. Monsanto was surprised to discover that the genes from GMO plants transferred themselves in the field to non-GMO plants. Obviously, some serious experimentation under very strict protocols would have to be pursued before any possible exposure could possibly occur. Remember Brewster's corollary to Murphy's Law: Murphy was an optimist.

By Robert Hopkins (not verified) on 24 Jun 2010 #permalink