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New Letters Added To the Genetic Alphabet
An anonymous reader writes with this excerpt from Quanta Magazine: [A]fter decades of work, [organic chemist Steven] Benner's team has synthesized artificially enhanced DNA that functions much like ordinary DNA, if not better. In two papers published in the Journal of the American Chemical Society last month, the researchers have shown that two synthetic nucleotides called P and Z fit seamlessly into DNA's helical structure, maintaining the natural shape of DNA. Moreover, DNA sequences incorporating these letters can evolve just like traditional DNA, a first for an expanded genetic alphabet.
In fact, the article continues, these new nucleotides can actually outperform their natural counterparts: "When challenged to evolve a segment that selectively binds to cancer cells, DNA sequences using P and Z did better than those without."
That's all I've got to say on the subject - even if I knew much about it the likely outcomes are speculative. Though not the predictable protests.
This is at least a bit over a year old.
Nature had a good publication on this a bit (same research group) over a year ago.
http://www.nature.com/news/fir...
For every problem, there is at least one solution that is simple, neat, and wrong.
Why didn't nature evolve these better letters?
it's alive.
It is not clear how the new nucleotides act when transcribing proteins but assuming its at least as efficient as the 4 letter code it could be a very interesting option for artificial viruses. A virus engineered to be totally dependent on the new nucleotides could be used much more safely even inside humans where there is no supply of them, they could infect the cells, produce proteins and a huge immune response but not a single copy of their genetic material could be produced. Also in a controlled environment they would thrive (cheap production?) but without P-Z no danger of new virus production so safety would not need to be as strict.
Applications on real organisms probably will take much longer time, but the simplicity of virus would make it a natural first step.
They've changed the genome from a 2 bit computer to a 3 bit computer. In theory they should be faster than us. But only over generations.
Never trust a man in a blue trench coat, Never drive a car when you're dead
This is how Zombies get made, just saying..
They say the new DNA outperforms the standard DNA in evolving to meet the researcher's criteria. That means it changes more easily. In other words, it's less stable.
In most situations, what we want is stability. Nature needs some ability to mutate and evolve, but considering that the wrong mutations result in cancer and death, too high of a mutation rate leads to failure. I suspect this is particularly true in long-lived larger organisms.
Of course we did not evolve wheels neither. Almost all animals above worms are torii topologically. (The digestive tract is the hole in the ring). There is one bacteria that has a free spinning flagellum. So nature started on that kind of disjoint topology, but could not scale it beyond bacteria. Two symbiotic animals one providing a wheel with shaft and another providing the bearing, together could have formed a wheeled animal. But that never happened, there is no path in the fitness landscape to achieve that configuration. Is it something fundamental like this that prevented six letter DNA
Or, more prosaically, the drawbacks outweigh the benefits. After all computers use binary not tertiary numbers. The four letter DNA is technically a binary system. Two pairs. So even if this thing escapes the laboratory it won't thrive in the wild and wipe out all the present forms of life Comforting if it is so.
sed -e 's/Chuck Norris/Rajnikant/g' joke > fact
...by sequencing cancer.
now we need to go OSS in diesel cars
They we could a genetic allele XYZZY! No doubt to be found in a maze of twisty little passages, all alike... :-)
This can be used as an escape character for example to embed information interpreted by something else with additional capability.
Maybe there can be medical chemicals that come with their own environmental data, "subtyping" ordinary cells to contain additional information that accompanies artificially added functionality. With such bookkeeping one could have virtually unlimited medical power controlled by "visit each cell only once" mechanisms instead of deploying weak incremental sauce to avoid thrashing everything.
Maybe this can allow for the introduction of an entirely orthogonal molecular namespace, enabling a clean, total, online/hot rewrite of an organisms entire biologial functionallity.
Maybe it can allow for embedding a level of translation into each cell that essentially decrypts encrypted dna making an organism immune to all infection.
Maybe additional namespace and can be used to simply trigger subroutines in an additional interpretation layer that halts aging or even reversing it.
None of this shall be patentable.
We had this with ASCII, and with UCS-2! No new letters please! Think of the poor programmers out there who have to rewrite binary protocols to support your changes.
This is part of a broader DARPA driven effort to expand what biology is capable of.
The end goal is to be able to create new materials (better fuels, medicines, building materials, etc) using biology. This requires expanding the "toolkit" biology uses to incorporate biologically incompatible elements, chemicals and processes.
So, starting from the end: We want a better biofuel. To do that, we want proteins that can better incorporate inorganic catalysts and work at higher energies than existing biology. To do that, we need different amino acids and protein construction machinery. To do that, we want to expand DNA to code for these new amino acids.
This is a "good" DARPA project in that we're not able to do all of this yet. What this means is that technology is pushed forward significantly, and we're able to clearly identify the real challenges.
Have gnu, will travel.
Of course there will be protests. So many people are using software at home to manipulate their genes as 2-bit values. This is basically DRM, or at least until people go back and fix all their code, which might even be technically illegal for them to do. Fuck that! We need to take to the streets, now!
"Believe me!" -- Donald Trump
___
If we replaced our DNA and RNA with these new letters, and updated all our DNA and RNA related proteins to use those letters instead, we should be immune to any virus. Of course, I don't think we could actually pull off such a change since we'd have to change so many proteins as well.
Don't waste your vote! Vote for whoever you want, unless you live in a swing state it won't matter anyways
The 64 three letter codons specify 20 amino acids and punctuation. For some amino acids the third element of the codon doesn't matter or has couple redundancies. This suggest an earlier two element codon with 15 amino acids or less.
Which one is ready to go?
some how couldn't be bothered to put the chemical name and structures of P and Z in
some how omitted that this isn't the first pair of new nucleotides that work this way
some how omitted that all four are patented up the yin-yang and cost >$1K/gram in quantity
... here we come!
Have you ever thought about why accepting the mark of the beast was an irrevocable decision? If it was a stamp/tattoo, why couldn't you scratch it off? If it was a chip, why couldn't you dig it out?
On the other hand, if the mark was something that fundamentally modified your DNA and the thing on the forehead/hand was merely a sign of your acceptance, the one-way nature of the mark makes a lot more sense.
Look. All I want is that colour changing thing from cuttlefish, and to glow in the dark. Get back in the lab and let me know when it's ready. I'll pay the delivery boy at the door.
Love without logic is insanity. And vice versa.