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FDA Greenlights a CRISPR-Based Test to Diagnose Covid-19
The test gives a result within an hour

A test that can diagnose the coronavirus within an hour using the gene-editing technology known as CRISPR has received emergency use authorization from the U.S. Food and Drug Administration.
The test was developed by Sherlock Biosciences, a biotech company launched in March 2019 by CRISPR pioneer Feng Zhang, a researcher at MIT and the Broad Institute.
In recent years, CRISPR has been imagined as a way to treat all kinds of diseases because of its ability to precisely cut DNA. It does that by using a molecular guide that searches for and locks onto a particular DNA sequence. Once there, an enzyme attached to the guide cuts the DNA at the right spot.
The technology can be used to snip out sections of DNA or replace genetic sequences entirely. A handful of early-stage clinical trials are testing the technique to treat certain cancer, blood disorders, and a type of inherited blindness. But researchers have also been experimenting with CRISPR as a way to diagnose diseases.
Sherlock Biosciences’ test works by programming CRISPR’s molecular guide to detect the presence of a specific genetic signature — in this case, the genetic signature for SARS-CoV-2 — in a nasal or throat swab. When that’s found, the CRISPR enzyme is activated and releases a signal. The test gives a result in an hour and can be run on basic equipment that most labs already have. The company says its test provides true positive and true negatives with 100% accuracy in patient samples, though it has not published data on the claim yet.
“The promise of CRISPR has been talked about for years now,” Rahul Dhanda, CEO and co-founder of Sherlock Biosciences, said in an interview, “We’ve been able to take the steps necessary to show that that promise is real.”
Currently, most tests to diagnose Covid-19 relies on a method called polymerase chain reaction, or PCR, which works by amplifying a tiny amount of viral genetic material so that it can be detected. While it’s a highly accurate and reliable lab technique, it’s also rather slow. It can take six to eight hours to run.