CRISPR/Cas-based detection of COVID-19

CRISPR/Cas-based detection of COVID-19
Navid Mousazadeh,¹ Seyed Sadegh Eslami,² Ali Mohammadi,³ Negin Mousazadeh,⁴ Mohammad bagher Naser,⁵ Hossein Rahimi,^6,*
1. Department of Medical Biotechnology, School of Medicine, Zanjan University of Medical Sciences, Zanjan, Iran.
2. Department of Medical Biotechnology, Faculty of Allied Medicine, Iran University of Medical Sciences, Tehran, Iran.
3. Department of Medicinal Chemistry, School of Pharmacy, Zanjan University of Medical Sciences, Zanjan, Iran
4. Department of Nursing, School of Nursing and Midwifery, Ardabil University of Medical Sciences, Ardabil, Iran
6. Department of Medical Biotechnology, School of Medicine, Zanjan University of Medical Sciences, Zanjan, Iran.
Introduction: The new coronavirus 2019 (COVID-19), which has affected millions of people all over the world has caused very great worldwide concern. The COVID-19 outbreak began in Wuhan, China and has spread rapidly all over the world, leading to the death of many people, and the number of cases of disease and mortality is increasing by the day. COVID-19 pandemic disease is caused by SARS-CoV-2 which is closely related to SARS-CoV [1]. This class of viruses is enveloped and has an RNA genome in size of almost 26-32 kb. SARS-CoV-2 contains 4 structural proteins called Spike (S), Nucleocapsid (N), Membrane (M) and Envelope (E) proteins which enter the host cell via S protein and replicate its own genome within the host cells [2, 3]. One of the major causes for the widely and rapid spread of the COVID-19 disease is the presence of a large number of asymptomatic COVID-19 positive cases. Therefore, the development of efficient diagnostic methods for sensitive, rapid and accurate diagnosis is essential for early diagnosis of this disease. The standard molecular technique for detecting SARS-CoV-2 worldwide is currently RT-qPCR. However, this technique faces challenges such as limited access to the required reagents, the need for trained personnel, need for equipped laboratories, and the long time required to achieve the final result. Precision, speed, efficiency, simplicity, and a broad range of CRISPR (clustered regularly interspaced short palindromic repeats) systems applications have motivated researchers to develop rapid and sensitive SARS-CoV-2 diagnostic systems based on CRISPR. Results of various studies on the use of the CRISPR system in the detection of SARS-CoV-2, have shown that CRISPR-based diagnostic systems for the diagnosis of SARS-CoV-2 have benefits such as high diagnostic speed, even in 30 min, no need for a well-equipped laboratory, portability, as well as high sensitivity and accuracy [4-6].
Methods: In writing this review article, we searched in various databases such as google scholar for keywords related to CRISPR and COVID-19 detection, and selected the most suitable papers.
Results: Since the outbreak of COVID-19, different groups have been working on CRISPR-based diagnostic systems for rapid and sensitive diagnosis of SARS-CoV-2. For instance, Ding et al. could successfully detect SARS-CoV-2 in 40 minutes, by developing the All-In-One Dual CRISPR-Cas12a (AIOD-CRISPR) system. AIOD-CRISPR system has advantages such as high sensitivity, high precision, high speed, single-molecule sensitivity and the capacity to naked-eye observe test results [7]. While the development of CRISPR-based diagnostic systems for the rapid detection of SARS-CoV-2 nucleic acid has been given special attention, these platforms have not addressed mutations and genomic editions relevant to the nucleic acid of the virus. In this regard the VaNGuard (Variant Nucleotide Guard) method was developed in an attempt to rapidly and sensitively identifying as well as recognize mutated and altered regions of the SARS-Cov-2 genome. The powerful, sensitive and fast VaNGuard system was found to be able to detect SARS-CoV-2 in 30 minutes [8]. A simple chemical method called STOP (SHERLOCK Testing in One Pot) was established in another try, capable of detecting COVID-19 in an hour. The STOP system is comparable in terms of sensitivity to RT-qPCR-based methods and has benefits such as simplicity, suitable for point-of - care, sensitivity, low cost, availability of test components and no need for RNA extraction [9].
Conclusion: Due to the advantages of CRISPR-based diagnostic systems such as high speed, simplicity, portability, high sensitivity and high specificity in the diagnosis of SARS-CoV-2, these diagnostic systems can be widely used to manage COVID-19 and future pandemics
Keywords: COVID-19, SARS-CoV-2, CRISPR