Artificial Bases Added to DNA

holy_calamity writes "Researchers have successfully added two 'unnatural' DNA letters to the code of life. They created two artificial base pairs that are treated as normal by an enzyme that replicates and fixes DNA inside cells. This raises the prospect of engineering life forms with genetic code not possible within nature, allowing new kinds of genetic engineering."

Comments

Artificial bases would have what effect?

[KublaiKhan]

We know what happens with the 'natural' bases--they indicate which amino acids are selected to produce which proteins.

I'm curious as to whether this will result in new kinds of proteins, or whether new amino acids will be required to be built, or what other effects might crop up.

It's interesting, don't get me wrong--but how -practical- is it?

Re:On the topic of "whatcouldpossiblygowrong"

[gnick]

Do we really only perceive biologists as madmen who want to do evil experients [sic] for the heck of it? No. But, even though I think that it's enormously cool what these folks did, the "whatcouldpossiblygowrong" tag seems appropriate here. While reading TFA, I couldn't help but think: "Scientists have created an unnatural but successfully replicating new genetic code? Did we just re-invent cancer?" Followed soon after by: "Cool!"

engineer tougher DNA

[smellsofbikes]

This could be really useful in the long-term: if we could substitute replacement codons that work with most of our existing DNA, it's one step to building really tough DNA. Right now, there are a lot of damage mechanisms like adjacent thymines linking resulting from exposure to chemicals or shortwave radiation, and replacement codons engineered to not be suseptible to these could make, say, protracted exposure to radiation outside the Earth's protective atmosphere more viable. Of course, then we'd have to engineer a whole set of enzymes to synthesize those new codons, which is an extremely hard project, but finding things that work as replacement base pairs, now, gives us time to study how they might fail and figure out what the best candidates are.

Re:engineer tougher DNA

[smellsofbikes]

I'm not in this field anymore so bear in mind my knowledge might be very dated.
Generally speaking, viruses that insert their DNA into eukaryotic DNA don't have a particular place that they do so: they get their DNA into the cell, and it then inserts itself randomly in some bit of exposed DNA. See, eukaryotic DNA is very tightly bound to accessory proteins that protect/maintain it and hold it in some sort of to my knowledge poorly understood large-scale organizational scheme that constitutes a chromosome, so it's not like you can get to just anywhere on the DNA, but the parts you CAN get to might not be consistent, depending on whether that particular DNA bit is being transcribed at the moment, or repaired, or what have you. So what happens is that viruses stick their DNA all *over* the place, and the vast majority of them are indeed in no-ops or unread/untranscribed sections and just sit there -- which is where all the endogenous retrovirus stuff we read about comes from. Complete replication of the DNA is rare -- it only happens when the cell needs to divide for some reason. Small-scale scanning and replication is very common because a cell's day-to-day enzyme turnover requires it. But that small scanning is less likely to hit the area where the virus DNA is because of the sheer size of the genome.
Eventually it'd be nice to migrate to a whole different genetic code and support enzymes, because then viruses would be instantly nonviable, but that's a long, long ways off. However, this research is the first step: if we had a wholly different DNA, and re-engineered the enzymes that make transfer RNA, which convert the messages read from DNA into protein, we could retain all the protein-handling enzymes we have, and everything they make, and 'only' swap out the DNA and RNA suite. That's still an enormous problem, but it's like 0.01% of the problem of trying to engineer new proteins and a whole metabolism based on them.

Genetic engineering WILL get scary

[Tablizer]

Even if its banned in the US, *other* countries will eventually start experimenting and create a super-race that works 80-hour-weeks without fatigue. Then other countries are going to have to follow to compete, or be left in the dust.

Re:On the topic of "whatcouldpossiblygowrong"

[should_be_linear]

Why is it that every single article that references any scientific development in the fields of genetics or molecular biology gets the "whatcouldpossiblygowrong" tag on Slashdot?

Because here on /. we know for sure that manipulating firmware is generally bad idea?

Re:On the topic of "whatcouldpossiblygowrong"

[Genus Marmota]

Do we really only perceive biologists as madmen who want to do evil experients for the heck of it? As someone working in the field, I say "no." They're weirdos and nutballs quite similar to the geeks that post on Slashdot, except that they frequently work with wet stuff and usually have more formal training.

My paranoia (and I own it as paranoia) is not that some mad scientist will do evil experiments. It's that perfectly "normal" and "rational" citizens running a large corporation will fsck up the planet by using this kind of technology in a stupid way on an industrial scale. By, say, monocropping all the wheat grown in North America with some GMO strain that can eat Roundup for breakfast. Or something like that.

The Audience is a Harsh Mistress

[Valdrax]

The real question is when did the slashdot audience turn to such un-comical jackasses who feel the need to take everything so seriously? I get it, you're well off, you like science, you like to stay on slashdot because in your opinion it represents the more "successful" members of society. But then, maybe you're just an arrogant prick, and maybe we're just having fun. I think the real problem here, as Mannie taught Mike, is the difference between "Funny," "Not Funny," and "Funny Once." Like much geek humor, it seems that all the humor in the use of the tag on this article come from mindless repetition, and the joke has officially been beaten into the ground.

Plus, let's face it -- there are articles where the tag is wonderfully appropriate as ironic snark, but this one isn't it. I mean, it's great for articles like this one about mass production of micro fission reactors or this one about the proposed future of military robots. Sometimes, it's funny when the very proposition of something going wrong is itself funny like with an article on a robot controlled by a monkey's brain.

However, dangers and recklessness involved in this project are next to nil. There's no irony and clever cynicism here. There's just the mindless misapplication of an overdone meme in a manner that makes Slashdot look like a bunch of technology fearing idiots. So yeah. While I don't think it's worth getting so worked up about, it is a stupidly applied tag and a failed attempt at humor.

Re:In regards to "been done before"

[philspear]

I've never heard of them being used for anti-viral applications. I've always heard of them being used in anti-cancer drugs. DNA has existed for a very long time, the reason it uses the same 5 nucleotides exclusively is because of stability issues. Obviously, you're going to want your genome to not fall apart, or rather to fall apart as little as possible while still being able to be replicated and read off of. The double helix and diploidy are additional ways to ensure stability and error correcting abilities, but even with all that, you still get lots of DNA breaks each day. I can't remember the order of magnitude right now, but it's quite a bit. The 4 usual nucleotides for genomic DNA (ACGT) are the most stable without gumming up the process. I've heard of several artificial nucleotides though that will incorporate into cells synthesizing new DNA (which cancer cells do) but they decrease genomic stability. Cancer cells DNA is often even more fragile than our DNA, so adding things like BrdU (I think it stands for bromodeoxyuridine, which cells mistake for thymidine) will selectively be taken up by cancer cells and will hopefully push their genomes over the edge to falling apart. BrdU can also be used as a way to specifically identify proliferating cells within organisms. Fully differentiated cells don't synthesize new DNA, so if you add in BrdU, it will only show up in cells that are still cycling (like adult stem cells). There are antibodies that specifically recognize BrdU, and you can detect those antibodies using secondary fluorescent antibodies. The result is that in tissue cross sections, proliferating cells will glow. Its unfortunate that the article is so blurby. I'm thinking though that the researchers don't know exactly how this DNA will be translated or will affect genomic stability. The real difference is that these bases will be copied, wheras BrdU and others won't. I'm very interested to know if these base pairs will copy as themselves (IE, the artificial base pair will be maintained in progeny cells) or if they will be paired with a normal base and the artifical one will be lost in progeny cells. If it's maintained, that would be very useful.

Re:Gene manipulation

[rholland356]

You have conflated cross-breeding with the work being done by these scientists. They have not just moved around bits of DNA, they have concocted a means for introducing new components into the DNA code. This becomes essentially life that is alien to Earth biology.

Combine this with work going on to introduce organisms that use proteins and enzymes that are beyond the range of all of earth's current life forms, and you have the basis for creating life that is impervious to all known biological agents.

So, while few of us fear Angus beef or white-shelled eggs, many of us fear pandemics of viruses that will kill hundreds of millions, maybe billions, and if engineered with these new components, might be unstoppable.

Re:On the topic of "whatcouldpossiblygowrong"

[xstonedogx]

I've been a frequent Slashdot contributer for 10 years and for some fucking reason not only can I not moderate, I cannot add tags.

I'm not sure what you're talking about. I didn't look through them all to see if any are more recent, but you tagged something as recently as Monday. Glancing through your tags, I have actually seen some of your tags up there; so it doesn't seem to be a matter of the tags not showing up. Is it that it just doesn't work sometimes? I've had that happen.

Right or wrong, with tags like "who cares", "thievingcunts", and "slownewsdaymeansdumbasfuck", it wouldn't surprise me if your 'tag karma' (or an arbitrary decision on the part of an editor) prevented you from tagging articles or from those tags showing up.

As for moderating, I'm with you. Excellent karma, frequent meta-moderation, and regular posting (in the past anyway) seemed to be a fast track to never having moderator points again for me.

Any Tool = Practical

[pragma_x]

The largest ramification I can think of is that using artifical base-pairs for DNA would lead to easier identification of engineered life in "the wild". This could be something as simple as a repeated "NOP" sequence that identifies the part and manufacturuer like a serial number, by way of frequency and sequence of these artifical protiens.

Things could even go as far as to impose government controls on engineered organisms, forcing such identification mechanisms for forensics purposes. This would be handy since you'd never mistake the engineered protiens for anything natural. It would also have serious patent control implications, as tracing the linage of a "pirated hybrid organism" would be possible.

Artifical base pairs could also help with more exotic DNA-based tools that only communicate in and amongst themselves, thereby side-stepping any natural DNA machinery about. This would be useful for medical purposes, or even to harden the engineered organism against swapping DNA with it's wild/natural ancestor types. For instance: any swap with a wild bacterium could be set to have a high likelyhood of killing both would-be hybrids.

Another set of possibilities is along the lines of bettering mother nature: to have a set of DNA-like building blocks that are more robust and capable than the natural ones. Better radiation endurance, for one, sticks out in my mind as a potentially useful attribute. I'm sure there's other tricks protiens can be taught.

As for side-effects: who knows. We might get another branch off the tree of life out of this, or sound the march towards post-humanism, or we might just get a bunch of really fragile microbes suitable for only the most niche of engineering and science tasks.