Leveraging Cas13a's trans -cleavage on RNA G-quadruplexes for amplification-free RNA detection.

In this study, we investigated Cas13a's efficacy in trans -cleaving RNA G-quadruplexes (rG4s) as an alternative to ssRNA reporters in CRISPR-Cas13a diagnostics. Our findings demonstrate enhanced efficiency due to the structural arrangement of rG4s. Implementing a simplified CRISPR-Cas13a system based on rG4, we identified SARS-CoV-2 infections in 25 patient samples within 1 hour without target pre-amplification.