Development and comparison of a novel multiple cross displacement amplification (MCDA) assay with other nucleic acid amplification methods for SARS-CoV-2 detection
Laurence Don Wai Luu, Michael Payne, Xiaomei Zhang, Lijuan Luo, Ruiting Lan
Received date: 4th October 2020
Objectives: To develop a novel multiple cross displacement amplification (MCDA) assay for COVID-19 and compare its speed and sensitivity to existing loop-mediated isothermal amplification (LAMP) and real-time PCR (RT-PCR) methods. Methods: Two MCDA assays targeting the SARS-CoV-2 N gene and ORF1ab was designed. The fastest time to detection and sensitivity of MCDA was compared to LAMP and RT-PCR using 7 DNA standards and transcribed RNA. Results: For the N gene, MCDA was consistently faster than LAMP and RT-PCR by 10 and 20 minutes, respectively with a fastest time to detection of 5.2 minutes. RT-PCR had the highest sensitivity with a limit of detection of 100 copies/reaction compared with MCDA (1000 copies/reaction) and LAMP (5000/reaction). For ORF1ab, MCDA and LAMP had similar speed with fastest time to detection at 9.7 and 8.4 minutes, respectively. LAMP was more sensitive for ORF1ab detection with 500 copies/reaction compared to MCDA (5000 copies/reaction). Conclusions: Different nucleic acid amplification methods provide different advantages. MCDA is the fastest nucleic acid amplification method for COVID-19 while RT-PCR is still the most sensitive. These advantages should be considered when determining the most suitable nucleic acid amplification methods for different applications.
This is an abstract of a preprint hosted on a preprint server, which is currently undergoing peer review at Scientific Reports. The findings have yet to be thoroughly evaluated, nor has a decision on ultimate publication been made. Therefore, the results reported should not be considered conclusive, and these findings should not be used to inform clinical practice, or public health policy, or be promoted as verified information.