By -Dr. VINAY KUMAR MEHRA
* Animal Biotechnology Centre, National Dairy Research Institute, Karnal, India.
vinay28mehra@yahoo.com
The novel corona virus disease 2019 (COVID-19) which is also known as severe acute respiratory syndrome corona virus 2 (SARS-Cov-2), has now become a Public Health Emergency of International Concern. In December the first case of COVID-19 was found in china after that it transmitted all over the world very rapidly and infects the large population and has emerged as a severe epidemic that causes severe respiratory syndrome in human (1). Till date there is only one diagnostic test i.e qPCR test to detect the COVID-19, but inadequate of reagent kits and equipments have slowed down the disease detection. So there is urgent need to develop another detection and prevention method to control the severe epidemic disease worldwide. Researchers at Howard Hughes Medical Institute, Cambridge and McGovern Institute for Brain Research at MIT,USA developed new CRISPR base protocol known as CRISPR-based SHERLOCK ( Specific High Sensitivity Enzymatic Reporter UnLOCKing) technique for the detection of COVID-19 which require less than an hour (2). So CRISPR/cas9 technology is the one of the promising area to treat this disease.
Recently the new CRISPR/cas9 technology has widely used for genome editing to cure many disease like retinal disorder, sickle-cell anemia, cancer immunotherapy, lung cancer metastasis, and many other diseases. There are two main components in CRISPR/cas9 technology one is cas9 enzyme and guide RNA (gRNA). The gRNA recognize the target site and cas9 enzyme cut the target site and cause insertion or deletion in the target site of the gene (4).There are various online tools like CRISPOR and CHOPCHOP which can be used for designing of gRNA.
But the main difficulty to treat corona virus disease by CRISPR/cas9 is that COVID-19 is a positive-strand RNA virus and target site of cas9 enzyme is DNA so to overcome this problem researchers at the New York Genome Center and New York University have developed a new type of CRISPR screen technology which target the RNA and this CRISPR enzyme is known as Cas13 which target the RNA instead of DNA (3). The Cas13 enzyme is Type VI CRISPR (clustered regularly interspaced short palindromic repeats) enzymes that have newly been recognized as programmable RNA-guided. So CRISPR-based genetic screening may provide an opportunity to identify and cure the COVID-19 in near future.
Reference:
1. Renhong Ya, Yuanyuan Zhang, Yaning Li, Lu Xia2, Yingying Guo2, Qiang Zhou (2020). Structural basis for the recognition of the SARS-CoV-2 by full-length human ACE2. DOI: 10.1126/science.abb2762.
2. Feng Zhang, Omar O. Abudayyeh and Jonathan S. Gootenberg (2020). A protocol for detection of COVID-19 using CRISPR diagnostics.
3. Hans-Hermann Wessels, Alejandro Méndez-Mancilla, Xinyi Guo, Mateusz Legut, Zharko Daniloski, Neville E. Sanjan (2020(. Massively parallel Cas13 screens reveal principles for guide RNA design. Nature Biotechnology, 2020; DOI: 10.1038/s41587-020-0456-9.
4. Yu W and Wu Z (2018) In Vivo Applications of CRISPR-Based Genome Editing in the Retina. Front. Cell Dev. Biol. 6:53. doi: 10.3389/fcell.2018.00053
