Previous pandemics have taught us that rapid and readily available detection methods are important for effective public health responses. However, current SARS-CoV-2 detection methods often take hours or even days to produce results.
April 16,2020, University of California, San Francisco, Qiu Huayan and Mammoth Biosciences
The researchers report a test based on Crispr something Cas12 that can identify SARS-CoV-2 from RNA extracted from the respiratory swabs of vid-19 patients. The test, called the "SARS-CoV-2 DNA endoenzyme target Crispr trans-reporting system" (DETECTR) . The test takes a sample of RNA, transcribes it back into the DNA, and then amplifies it using a technique called isothermal amplification. The gene sequences of the SARS-CoV-2 envelope (e) and Nucleocapsid (N) are then detected by CRISPR something Cas12, which cuts the reporter molecules that confirm the presence of the virus. The authors tested the system on clinical samples from 36 COVID-19 patients and 42 other respiratory disease patients. Compared with RT-PCR used by the Centers for Disease Control and Prevention in the United States, the positive predictive accuracy was 95% and the negative predictive accuracy was 100% .
In contrast to RT-PCR, which typically takes several hours to detect and requires special equipment and a hot and cold cycle, the DETECTR has only two fixed operating temperatures and, after about 45 minutes, can act like a home pregnancy test, read the results on the visual read bar.