The JRC has designed and is providing to laboratories the EURM-019 single stranded RNA (ssRNA) fragments of SARS-CoV-2 product.
Recently a variant of SARS-CoV-2 has been identified in the UK - SARS-CoV-2 VUI 202012/01 (here called the new variant). This variant differs in several positions from the reference SARS-CoV-2 sequence that was used as the basis for the development of the JRC reference materials.
Therefore, it is very important for control authorities to know which methods, in combination with the JRC reference material can detect the new variant.
EURM-019 is a solution containing a stabilised in vitro transcripted (IVT) synthetic single stranded RNA (ssRNA) in buffer.
It is "intended to be used as a positive quality control sample in the testing for the presence of the coronavirus SARS-CoV-2, also referred to as 2019-nCoV or virus causing the disease COVID-19.
It can be used to verify the correctness of the transcription and amplification steps for the SARS-CoV-2 real-time RT-PCR assays".
This universal synthetic ssRNA of 880 nucleotides contains 8 target regions that can be amplified by the following RT-PCR assays:
- N1, N2 and N3 gene developed by the Centers for Disease Control and Prevention (USA);
- E gene and the RdRP gene developed by the Charité (DE);
- N gene developed by the Japanese National Institute of Infectious Diseases (JP);
- N gene developed by the Ministry of Heath of Thailand (TH);
- S gene developed by the Joint Research Centre (JRC) of the European Commission.
An in-depth in silico PCR simulation with the new variant sequence (data not shown) shows that only the assay designed on the S gene developed by JRC is potentially affected, because there is a single mismatch between the probe and the new variant.
All other methods are still able to detect the new variant, and the EURL-019 RNA can therefore be used, along with those methods, as positive quality control.
- 23 joulukuu 2020