XNA is Synthetic, Stronger DNAAs if science wasn’t terrifying enough by itself, scientists have created an artificial form of DNA that is, simply put, better than its natural equivalent. Research has shown that XNA is capable of reproducing just like DNA is, but that it is stronger and more resistant to damage.
Yeah, we’re all doomed.
All organisms have a strand of instructions that code what they are. Those instructions are called DNA. All known organisms have DNA and RNA based on the same basic components.
But not XNA. XNA has had one of the components replaced with another. The X stands for “xeno,” which, in one of its definitions, means “alien.” The deoxyribose and ribose sugar groups in DNA and RNA, respectively, have been replaced. There are many different replacements used, and all are structurally interchangeable with what they replace. But the replacements also change how the XNA behaves.
A research team has managed to create various types of XNA. Using clever engineering tricks, they have even managed to make the DNA reproduce, though it does this by temporarily creating analogous DNA. This process is even fairly accurate, with LNA having a 95% correct transcription rate and CeNA having a 99.6% correct transcription rate. With those numbers, it is possible for evolution to occur. Why? Because evolution is all about being able to carry information from one generation to the next. The higher the correct transcription rate is, the more information can be transferred from generation to generation.
Of course, the team tested this. Using guided evolution, the team aimed to make their XNA capable of binding to traditional RNA or proteins. Their success means that XNA could, in theory, work in artificial organisms.
Why Make XNA?Part of the quest of XNA is to find a simpler set of instructions that might have existed before DNA. DNA is amazingly complex, after all, so it would have been easier for life to evolve with a simpler structure.
Beyond that inquisitive research, however, XNA can be built to resist cellular processes that destroy DNA. The research team conducting the experiments at Cambridge, led by Philipp Holliger and Vitor Pinheiro, was looking to make nucleic acid treatments last longer.
"Overall, this leads to high cost and a high failure rate for potential therapies - there is still only a single licenced [nucleic acid-based] drug on the market (Macugen)”said Pinhero. The solution, they decided, was artificial XNA. Because XNA is so new, the body has trouble degrading it. That means that treatments can last much, much longer.
Finally, XNA could make the creation of fully synthetic organisms easier. Synthetic organisms, made from scratch with a custom strand of DNA, have long been a dream. But they are also insanely difficult to make. It was only recently that we managed to make an artificial organism off of an existing blueprint. XNA could be the key, though Pinhero says that such lifeforms are still a ways off. To do so, XNA would need to be able to replicate without any normal biological elements. That won’t happen for quite a while.
But this work does mark a major step in the right direction. With XNA as the base, we might see artificial organisms within a few decades.