https://www.technologyreview.com/s/...eate-the-china-coronavirus-from-its-dna-code/
Biologists rush to re-create the China coronavirus from its DNA code
The world is watching with alarm as China struggles to contain a dangerous new virus, now being called SARS-CoV-2. It has quarantined entire cities, and the US has put a blanket ban on travellers who’ve been there.
Health officials are scrambling to understand how the virus is transmitted and how to treat patients.
But in one University of North Carolina lab, there’s a different race. Researchers are trying to create a copy of the virus. From scratch.
Led by Ralph Baric, an expert in coronaviruses—which get their name from the crown-shaped spike they use to enter human cells—the
North Carolina team expects to recreate the virus starting only from computer readouts of its genetic sequence posted online by Chinese labs last month.
The remarkable ability to “boot up” viruses from genetic instructions is made possible by companies that manufacture custom DNA molecules, such as Integrated DNA Technology, Twist Bioscience, and Atum. By ordering the right genes, which cost a few thousand dollars, and then stitching them together to create a copy of the coronavirus genome, it’s possible to inject the genetic material into cells and jump-start the virus to life.
The ability to make a lethal virus from mail-order DNA was first demonstrated 20 years ago. It’s enough of a bioterrorism concern that companies carefully monitor who is ordering which genes. But it’s also an important way to respond to a sudden outbreak, since synthetic virus recipes give researchers powerful ways to study treatments, vaccines, and how mutations could make it more dangerous.
When a synthetic virus is better than the real thing
Baric’s North Carolina lab, which specializes in engineering viruses, has previously butted heads with Washington agencies over the work, which has included synthesizing
new, never before seen coronaviruses that can infect mice. In 2014, the National Institutes of Health
froze funding to several labs, including Baric’s, over concerns that such research was too risky. The funding was later reinstated.
For the China virus, Baric said in a telephone interview, his team placed an order for matching DNA from a manufacturer last month. Their first step was to go online and look at genetic sequences of the virus. They then compared several available sequences, which differ slightly, and picked a “consensus” version to have manufactured.
Once Baric gets his DNA, something that could take a month, he plans to inject the genetic instructions into cells. If things go as planned, the cells should begin making actual infectious viral particles.
A image of cornaviruses present in the cells of the first US case of a new pneumonia-causing disease.
CDC
By rolling their own germs, scientists can get hold of viruses even if they can’t obtain them directly from a country, especially one that’s in the grip of an epidemic. Baric says so far samples of the live virus from patients have not been made widely available from China. “This is the future in terms of how the medical research community responds to a new threat,” says Baric.
The real virus and the synthetic one should be basically identical. But with the synthetic one, “we have a DNA copy that we can go back to over and over and over again, to make genetically identical viruses,” says Timothy Sheahan, a researcher at UNC who works with Baric.
Starting from these copies, scientists can remove genes, add others, and figure out things like what makes the germ spread and how it gains access to human cells. Sheahan wants to try
infecting mice with the virus and giving them various drugs to see what stops it.
Artificial copies may also help scientists keep up with the outbreak’s unpredictable path. “I worry this virus is going to mutate in the course of the epidemic, and this would allow me to study what effects those mutations have,” says Stanley Perlman, a microbiologist who works on coronaviruses at the University of Iowa. “The synthetic virus is just a substitute for the actual virus, but with the DNA clone you can manipulate it and find the weak points and develop a therapy.”
During past outbreaks, scientists would have had to wait months or years to get a look at the germ behind an outbreak. But with SARS-CoV-2 it took only weeks until its genetic sequence was posted online. Immediately, some scientists began analyzing the genetic data, comparing it to viruses from bats, snakes and pangolins; they concluded it could have begun circulating last November.
Biotech companies, governments, and universities also quickly started ordering physical copies of particular genes found in the virus. DNA manufacturers say they have been deluged with orders for virus parts, including those useful for verifying diagnostic tests and others needed to make potential vaccines.
“It’s been a pretty dramatic uptick, starting with the publication of the genome,” says Adam Clore, technical director of synthetic biology at IDT, based in Iowa, and one of the world’s largest sellers of DNA. “It’s high priority. There are a number of institutions that are devoting nearly all their energy working on detection or vaccines.”
Still, most researchers need only one or two genes from the virus to carry forward work on tests and vaccines. Baric’s lab in North Carolina is the only one in the US known to be trying to re-create the virus completely from ordered DNA parts.
How to keep deadly viruses out of the wrong hands
It was in the early 2000s that scientists first showed that synthetic DNA strands could be used to “resurrect” viruses just from their genetic code. A team in New York State
did it with polio, producing infectious material from DNA they ordered online.
The technology immediately created bio-weapon worries. What if terrorists used the technique to resurrect smallpox? That hasn’t happened, but it does mean that scourges like polio, smallpox—and now the Chinese coronavirus—cannot now ever be truly wiped out. Researchers at the US Centers for Disease Control and Prevention (CDC) drove that point home in 2005 when they
resurrected the influenza virus that killed tens of millions in 1918-1919.
To keep the technology out of the hands of evil-doers, companies that manufacture DNA banded together a few years ago to limit access to dangerous genes. The big US players have all agreed to compare incoming DNA orders to a database of about 60 lethal germs and toxins called “select agents” so that only authorized labs can ever obtain the DNA needed to resurrect them.