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Review article: Biomedical intelligence

Vol. 151 No. 4950 (2021)

PCR performance in the SARS-CoV-2 Omicron variant of concern?

  • César M. J. A. Metzger
  • Reto Lienhard
  • Helena M. B. Seth-Smith
  • Tim Roloff
  • Fanny Wegner
  • Jonas Sieber
  • Michael Bel
  • Gilbert Greub
  • Adrian Egli
Cite this as:
Swiss Med Wkly. 2021;151:w30120



The new SARS-CoV-2 Omicron variant (B.1.1.529) has been recently declared a Variant of Concern due to a series of important mutations in the viral spike protein and especially in the receptor-binding domain. While investigations into the spread of this new variant are ongoing, the first cases have been detected in Switzerland. Important questions have been raised: (1) Will the PCR assays commonly used to detect SARS-CoV-2 still work for the Omicron variant? (2) Can specific PCR features, e.g. S-gene dropout, be used to identify potential Omicron samples?

In this minireview we provide current knowledge on the Omicron variant and guidance on its PCR validation.


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