Diagnosis of SARS-CoV-2 infection. PCR competitor?
The roots of the idea for this method lie in a discovery that won the 2020 Nobel Prize in Chemistry. The prize itself was awarded for a genome editing technique called CRISPR / Cas9. It would seem, what does this have to do with the diagnosis of SARS-CoV-2 infection? Not entirely straightforward, but it does. The fact is that the “genomic scissors” – the Cas9 enzyme, which can be precisely directed to certain points of DNA with the help of “RNA conductors” – has “relatives”. One of them is the Cas13a enzyme. It, like Cas9, can be “directed” to the desired point in the genome, but not DNA, but RNA. Moreover, the RNA target for Cas13a must be single-stranded. This is exactly what the genomes of most RNA viruses are.
Well, well, Cas13a in combination with RNA conductors can be “directed” to certain regions of the RNA genome of the virus (in our case, SARS-CoV-2). The enzyme endonuclease will cut the viral RNA at this point. What’s next? How can this be used to detect a virus? There won’t be more viral RNA. And the essence of PCR and all other methods for amplifying nucleic acids is an avalanche-like copying of target molecules. This determines their ultra-high sensitivity. How to provide hypersensitivity without amplification of viral genomes?Поділитися цим: