Rapid Detection of SARS-CoV-2 Variants by Molecular Clamping Technology Based RT-qPCR

Abstract
Given the challenges that fast-changing SARS-CoV-2 variants have caused in terms of rapid spread and reduced vaccine efficacy, a rapid and cost-effective assay that can detect new and emerging variants is greatly needed worldwide. We have successfully applied the xenonucleic acid-based molecular-clamping technology to develop a multiplex RT-qPCR assay for SARS-CoV-2 multivariant detection. The assay was tested on 649 nasopharyngeal swab samples that were collected from California and Ohio. The assay was able to correctly identify all 36 Delta variant samples as it accurately detected D614G, T478K and L452R mutations. In addition, the assay was able to correctly identify all 34 Omicron samples by detecting K417N, T478K, N501Y and D614G mutations. This technique reliably detects a variety of variants and has an analytical sensitivity of 100 copies/mL. In conclusion, this novel assay can serve as a rapid and cost-effective tool to facilitate large-scale detection of SARS-CoV-2 variants.