Triple Helix — Designing a New Molecule of Life 152
Anti-Globalism sends in this quote from Scientific American about attempts to synthesize molecules that function as well or better than the natural building blocks of life:
"A molecule that some researchers study in pursuit of this vision is peptide nucleic acid (PNA), which mimics the information-storing features of DNA and RNA but is built on a proteinlike backbone that is simpler and sturdier than their sugar-phosphate backbones. ... Many studies have demonstrated PNA's suitability for modifying gene expression, mostly in molecular test-tube experiments and in cell cultures. Studies in animals have begun, as has research on ways to transform PNA into drugs that can readily enter a person's cells from the bloodstream. ... Some scientists have suggested that PNAs or a very similar molecule may have formed the basis of an early kind of life at a time before proteins, DNA and RNA had evolved. Perhaps rather than creating novel life, artificial-life researchers will be re-creating our earliest ancestors."
Good (Score:2, Interesting)
PNA Too stable? (Score:5, Interesting)
Perhaps PNA is too stable, so that life forms based on it couldn't evolve through mutations quickly enough to adapt to changes.
Re:Binding Affinity (Score:4, Interesting)
That is, do DNA-based cells exposed to PNA stop being able to reproduce themselves? (DNA unzips, PNA wiggles in and binds, everything shuts down)
Re:Binding Affinity (Score:3, Interesting)
Re:Er. (Score:5, Interesting)
PNA might function better than DNA/RNA, but its cost (resources, time to create) is higher and couldn't be afforded by the first organisms.
By your logic humans who wouldn't survive a nuclear war are less efficient than roaches that would survive it.
Just, roaches will never start a nuclear war in the first place.
Re:Binding Affinity (Score:3, Interesting)
what could possible go wrong (Score:2, Interesting)
This deserves a "whatcouldpossiblygowrong" tag. They will end up developing some horrible new superbug that will kill us all or create some other horrible disease, or mess something up. When dealing with these sorts of things there are unintended consequences and the results can be disasterous. Manipulating genetics is far too dangerous in my opinion, especially since organisms self reproduce. We could end up contaminating our food supply or unleashing mutants that invade the world. It has already been shown that some genetically altered organisms cause kidney and liver damage and cancer, since these genes can escape into the environment reversing this damage can be nearly impossible. It has been shown that genetic engineering leads to totally unexpected, and often deadly results yeilding toxic foods and highly deformed organisms. This is due to the sheer complexity of the genetic system that we will never be able to understand, and that humans have evolved and developed to be able to process and utililize certain naturally occuring chemicals proteins, genetic engineering creates proteins which have never been consumed before and are well outside the normal limits of what would be produced by natural conception processes, as the food we have eaten for millions of years has been so, it is not surprising that these artificial synthetic foods are causing problems in peoples bodies. We are best staying with what our bodies are naturally adapted to handle over millions of years of evolution and away from risky frankenstienian experiments, and messing with or altering living things. Technology is great in your ipod, but i dont want it on my plate.
Re:Er. (Score:2, Interesting)
Which is better (from a selfish point of view)?
If your goal is to get off this rock quick, why wait until you've evolved and amassed enough science and tech to go into space (tanking the economy in the process) when you can just hitch a ride?
Earth-born bacteria that hitchhiked along with Mars rovers Spirit and Opportunity possibly are now living on Mars. We (humans) are not.
Re:Er. (Score:2, Interesting)
I completely agree that evolution doesn't mean 'progress' or things getting 'better'. Nevertheless, there unarguably has been a trend in the direction of more COMPLEX life forms over the entire period of evolution of life on earth. Not saying that More Complex means Better. However, More Complex generally suggests More Sophisticated, which, in the popular imagination at least, is perceived as 'better'.