Late Night, Unedited Musings on Synthesizing Secret Genomes
By now you have probably heard that a meeting took place this past week at Harvard to discuss large scale genome synthesis. The headline large genome to synthesize is, of course, that of humans. All 6 billion (duplex) bases, wrapped up in 23 pairs of chromosomes that display incredible architectural and functional complexity that we really don't understand very well just yet. So no one is going to be running off to the lab to crank out synthetic humans. That 6 billion bases, by the way, just for one genome, exceeds the total present global demand for synthetic DNA. This isn't happening tomorrow. In fact, synthesizing a human genome isn't going to happen for a long time.
But, if you believe the press coverage, nefarious scientists are planning pull a Frankenstein and "fabricate" a human genome in secret. Oh, shit! Burn some late night oil! Burn some books! Wait, better — burn some scientists! Not so much, actually. There are a several important points here. I'll take them in no particular order.
First, it's true, the meeting was held behind closed doors. It wasn't intended to be so, originally. The rationale given by the organizers for the change is that a manuscript on the topic is presently under review, and the editor of the journal considering the manuscript made it clear that it considers the entire topic under embargo until the paper is published. This put the organizers in a bit of a pickle. They decided the easiest way to comply with the editor's wishes (which were communicated to the authors well after the attendees had made travel plans) was to hold the meeting under rules even more strict than Chatham House until the paper is published. At that point, they plan to make a full record of the meeting available. It just isn't a big deal. If it sounds boring and stupid so far, it is. The word "secret" was only introduced into the conversation by a notable critic who, as best I can tell, perhaps misconstrued the language around the editor's requirement to respect the embargo. A requirement that is also boring and stupid. But, still, we are now stuck with "secret", and all the press and bloggers who weren't there are seeing Watergate headlines and fame. Still boring and stupid.
Next, It has been reported that there were no press at the meeting. However, I understand that there were several reporters present. It has also been suggested that the press present were muzzled. This is a ridiculous claim if you know anything about reporters. They've simply been asked to respect the embargo, which so far they are doing, just like they do with every other embargo. (Note to self, and to readers: do not piss off reporters. Do not accuse them of being simpletons or shills. Avoid this at all costs. All reporters are brilliant and write like Hemingway and/or Shakespeare and/or Oliver Morton / Helen Branswell / Philip Ball / Carl Zimmer / Erica Check-Hayden. Especially that one over there. You know who I mean. Just sayin'.)
How do I know all this? You can take a guess, but my response is also covered by the embargo.
Moving on: I was invited to the meeting in question, but could not attend. I've checked the various associated correspondence, and there's nothing about keeping it "secret". In fact, the whole frickin' point of coupling the meeting to a serious, peer-reviewed paper on the topic was to open up the conversation with the public as broadly as possible. (How do you miss that unsubtle point, except by trying?) The paper was supposed to come out before, or, at the latest, at the same time as the meeting. Or, um, maybe just a little bit after? But, whoops. Surprise! Academic publishing can be slow and/or manipulated/politicized. Not that this happened here. Anyway, get over it. (Also: Editors! And, reviewers! And, how many times will I say "this is the last time!")
(Psst: an aside. Science should be open. Biology, in particular, should be done in the public view and should be discussed in the open. I've said and written this in public on many occasions. I won't bore you with the references. [Hint: right here.] But that doesn't mean that every conversation you have should be subject to review by the peanut gallery right now. Think of it like a marriage/domestic partnership. You are part of society; you have a role and a responsibility, especially if you have children. But that doesn't mean you publicize your pillow talk. That would be deeply foolish and would inevitably prevent you from having honest conversations with your spouse. You need privacy to work on your thinking and relationships. Science: same thing. Critics: fuck off back to that sewery rag in — wait, what was I saying about not pissing off reporters?)
Is this really a controversy? Or is it merely a controversy because somebody said it is? Plenty of people are weighing in who weren't there or, undoubtedly worse from their perspective, weren't invited and didn't know it was happening. So I wonder if this is more about drawing attention to those doing the shouting. That is probably unfair, this being an academic discussion, full of academics.
Secondly (am I just on secondly?), the supposed ethical issues. Despite what you may read, there is no rush. No human genome, nor any human chromosome, will be synthesized for some time to come. Make no mistake about how hard a technical challenge this is. While we have some success in hand at synthesizing yeast chromosomes, and while that project certainly serves as some sort of model for other genomes, the chromatin in multicellular organisms has proven more challenging to understand or build. Consequently, any near-term progress made in synthesizing human chromosomes is going to teach us a great deal about biology, about disease, and about what makes humans different from other animals. It is still going to take a long time. There isn't any real pressing ethical issue to be had here, yet. Building the ubermench comes later. You can be sure, however, that any federally funded project to build the ubermench will come with a ~2% set aside to pay for plenty of bioethics studies. And that's a good thing. It will happen.
There is, however, an ethical concern here that needs discussing. I care very deeply about getting this right, and about not screwing up the future of biology. As someone who has done multiple tours on bioethics projects in the U.S. and Europe, served as a scientific advisor to various other bioethics projects, and testified before the Presidential Commission on Bioethical Concerns (whew!), I find that many of these conversations are more about the ethicists than the bio. Sure, we need to have public conversations about how we use biology as a technology. It is a very powerful technology. I wrote a book about that. If only we had such involved and thorough ethical conversations about other powerful technologies. Then we would have more conversations about stuff. We would converse and say things, all democratic-like, and it would feel good. And there would be stuff, always more stuff to discuss. We would say the same things about that new stuff. That would be awesome, that stuff, those words. <dreamy sigh> You can quote me on that. <another dreamy sigh>
But on to the technical issues. As I wrote last month, I estimate that the global demand for synthetic DNA (sDNA) to be 4.8 billion bases worth of short oligos and ~1 billion worth of longer double-stranded (dsDNA), for not quite 6 Gigabases total. That, obviously, is the equivalent of a single human duplex genome. Most of that demand is from commercial projects that must return value within a few quarters, which biotech is now doing at eye-popping rates. Any synthetic human genome project is going to take many years, if not decades, and any commercial return is way, way off in the future. Even if the annual growth in commercial use of sDNA were 20% — which is isn't — this tells you, dear reader, that the commercial biotech use of synthetic DNA is never, ever, going to provide sufficient demand to scale up production to build many synthetic human genomes. Or possibly even a single human genome. The government might step in to provide a market to drive technology, just as it did for the human genome sequencing project, but my judgement is that the scale mismatch is so large as to be insurmountable. Even while sDNA is already a commodity, it has far more value in reprogramming crops and microbes with relatively small tweaks than it has in building synthetic human genomes. So if this story were only about existing use of biology as technology, you could go back to sleep.
But there is a use of DNA that might change this story, which is why we should be paying attention, even at this late hour on a Friday night.
DNA is, by far, the most sophisticated and densest information storage medium humans have ever come across. DNA can be used to store orders of magnitude more bits per gram than anything else humans have come up with. Moreover, the internet is expanding so rapidly that our need to archive data will soon outstrip existing technologies. If we continue down our current path, in coming decades we would need not only exponentially more magnetic tape, disk drives, or flash memory, but exponentially more factories to produce these storage media, and exponentially more warehouses to store them. Even if this is technically feasible it is economically implausible. But biology can provide a solution. DNA exceeds by many times even the theoretical capacity of magnetic tape or solid state storage.
A massive warehouse full of magnetic tapes might be replaced by an amount of DNA the size of a sugar cube. Moreover, while tape might last decades, and paper might last millennia, we have found intact DNA in animal carcasses that have spent three-quarters of a million years frozen in the Canadian tundra. Consequently, there is a push to combine our ability to read and write DNA with our accelerating need for more long-term information storage. Encoding and retrieval of text, photos, and video in DNA has already been demonstrated. (Yes, I am working on one of these projects, but I can't talk about it just yet. We're not even to the embargo stage.)
Governments and corporations alike have recognized the opportunity. Both are funding research to support the scaling up of infrastructure to synthesize and sequence DNA at sufficient rates.
For a “DNA drive” to compete with an archival tape drive today, it needs to be able to write ~2Gbits/sec, which is about 2 Gbases/sec. That is the equivalent of ~20 synthetic human genomes/min, or ~10K sHumans/day, if I must coin a unit of DNA synthesis to capture the magnitude of the change. Obviously this is likely to be in the form of either short ssDNA, or possibly medium-length ss- or dsDNA if enzymatic synthesis becomes a factor. If this sDNA were to be used to assemble genomes, it would first have to be assembled into genes, and then into synthetic chromosomes, a non trivial task. While this would be hard, and would to take a great deal of effort and PhD theses, it certainly isn't science fiction.
But here, finally, is the interesting bit: the volume of sDNA necessary to make DNA information storage work, and the necessary price point, would make possible any number of synthetic genome projects. That, dear reader, is definitely something that needs careful consideration by publics. And here I do not mean "the public", the 'them' opposed to scientists and engineers in the know and in the do (and in the doo-doo, just now), but rather the Latiny, rootier sense of "the people". There is no them, here, just us, all together. This is important.
The scale of the demand for DNA storage, and the price at which it must operate, will completely alter the economics of reading and writing genetic information, in the process marginalizing the use by existing multibillion-dollar biotech markets while at the same time massively expanding capabilities to reprogram life. This sort of pull on biotechnology from non-traditional applications will only increase with time. That means whatever conversation we think we are having about the calm and ethical development biological technologies is about to be completely inundated and overwhelmed by the relentless pull of global capitalism, beyond borders, probably beyond any control. Note that all the hullabaloo so far about synthetic human genomes, and even about CRISPR editing of embryos, etc., has been written by Western commentators, in Western press. But not everybody lives in the West, and vast resources are pushing development of biotechnology outside of the of West. And that is worth an extended public conversation.
So, to sum up, have fun with all the talk of secret genome synthesis. That's boring. I am going off the grid for the rest of the weekend to pester litoral invertebrates with my daughter. You are on your own for a couple of days. Reporters, you are all awesome, make of the above what you will. Also: you are all awesome. When I get back to the lab on Monday I will get right on with fabricating the ubermench for fun and profit. But — shhh — that's a secret.