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bioRxiv · 10.1101/2020.07.06.189860

Comparison of three TaqMan Real-Time Reverse Transcription-PCR assays in detecting SARS-CoV-2

Xiao, Y.·Li, Z.·Wang, X.·Wang, Y.·Wang, G.·Ren, L.·Li, J.
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Abstract

Quick and accurate detection of SARS-CoV-2 is critical for COVID-19 control. Dozens of real-time reverse transcription PCR (qRT-PCR) assays have been developed to meet the urgent need of COVID-19 control. However, methodological comparisons among the developed qRT-PCR assays are limited. In the present study, we evaluated the sensitivity, specificity, amplification efficiency, and linear detection ranges of three qRT-PCR assays, including the assays developed by our group (IPBCAMS), and the assays recommended by WHO and China CDC (CCDC). The three qRT-PCR assays exhibited similar sensitivities, with the limit of detection (LOD) at about 10 copies per reaction (except the ORF 1b gene assay in CCDC assays with a LOD at about 100 copies per reaction). No cross reaction with other respiratory viruses were observed in all of the three qRT-PCR assays. Wide linear detection ranges from 106 to 101 copies per reaction and acceptable reproducibility were obtained. By using 25 clinical specimens, the N gene assay of IPBCAMS assays and CCDC assays performed better (with detection rates of 92% and 100%, respectively) than that of the WHO assays (with a detection rate of 60%), and the ORF 1b gene assay in IPBCAMS assays performed better (with a detection rate of 64%) than those of the WHO assays and the CCDC assays (with detection rates of 48% and 20%, respectively). In conclusion, the N gene assays of CCDC assays and IPBCAMS assays and the ORF 1b gene assay of IPBCAMS assays were recommended for qRT-PCR screening of SARS-CoV-2.Competing Interest StatementThe authors have declared no competing interest.View Full Text

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Xiao, Y., Li, Z., Wang, X., Wang, Y., Wang, G., Ren, L., Li, J.. 2020-07-06. Comparison of three TaqMan Real-Time Reverse Transcription-PCR assays in detecting SARS-CoV-2. https://doi.org/10.1101/2020.07.06.189860

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