Slashdot Mirror
Artificial DNA Replicates and 'Evolves'
ananyo writes "Scientists have demonstrated that several lab-made variants of DNA can store and transmit information much like the genuine article. DNA is made up of nucleic acid bases — labelled A, C, G and T — on a backbone made of phosphates and the sugar deoxyribose. The artificial polymers, dubbed XNAs, carry the normal genetic 'alphabet' on a backbone made using different sugars. The researchers engineered enzymes that transcribed DNA into the various XNAs, then back into new DNA strands. Faithful genetic transmission over successive DNA-to-XNA cycles allowed researchers to select for only those XNAs that attached to certain target proteins from a pool of random samples — a process akin to evolution over multiple generations (abstract). The research confirms for the first time that replication, heredity and evolution can take place in artificial DNA-like molecules."
The ability to "breed" chemicals that bond to specific proteins sounds like it could cure a boatload of previously incurable diseases. I'm not sure that is what the researchers are going for, but to me, this sounds like "miracle cure" type stuff.
Bacteria/virus/tumor cells/prions go in, perfectly tailored antibody components come out. Attach some highly reactive oxides/chlorides and you have a targeted antibiotic. At least that's how the science fiction version of this would go.
You need a certain degree of faithfulness: if you lose too much information each transcription, there's no selection. I think geneticists have math for this that I'm not perfeclty versed in, but if you, say, lose 50% of your genome each generation, the increased chance that the next generation gets your good genes is negligible compared to the chance that they would have received that gene randomly. The news here is that they got transcription good enough to "evolve" their XNA, that is a high enough proportion of each generation was viable that they could be cycled through to the next population.