The Genomes of SARS-CoV-2 and Related Coronaviruses: Are Accessory Proteins Key for Pathogenesis?

Objective: In January 2020, scientists deciphered the first genome of SARS-CoV-2 that has created a ravage in the world by infecting over 30 million people worldwide with above 0.95 million deaths as of mid-September 2020. With no potent therapeutics against COVID-19, researchers around the world are relentlessly working for the development of a vaccine that can ease the pain the world is suffering today, both in terms of economic and psychological instability. Understanding the genome of SARS-CoV-2 is essential to decipher the keys that would help scientists to develop drugs or vaccines to prevent the disease. Methods: Coronaviruses are not unknown to the human as other than SARS-CoV-2, at least six additional coronaviruses (SARS-CoV, MERS-CoV, HCoV-229E, HCoV-NL63, HCoV-OC43, and HCoV-HKU1) are known that causes mild to severe diseases in human. We have compared the sequences of these seven coronaviruses to identify the key regions which are responsible for pathogenesis. Results: The genomes of the seven coronaviruses that are known to infect humans differ significantly, especially in the regions of accessory genes. Conclusion: The analysis of these virus genomes is the key to find out targets for the development of a potent drug or vaccine against COVID-19.