A preliminary report has been published in the bioRxiv website detailing what could possibly be the first "significant" mutation of SARS-CoV-2, the novel coronavirus causing COVID-19. Experts, however, told Newsweek that the discovery is not likely to jeopardize the efforts in creating a vaccine.
The study authors examined 106 genetic samples of the virus and compared them with 39 SARS virus genome sequences. The SARS virus triggers Severe Acute Respiratory Syndrome, from which it got its name. An outbreak of this virus occurred in 2002.
The nearly complete or complete SARS-CoV-2 data came from records from the following: US - 54; China - 35; Spain - 3; Brazil - 2; as well as one record each from Finland, Australia, Italy, India, Nepal, Sweden, and South Korea.
The report has not yet undergone peer review for publication in reputable scientific journals. However, the release of such a study is significant as it sparks debate and discussion among scientists, which could help in finding a solution to an urgent situation such as this pandemic.
During the SARS outbreak, it had a higher rate of mutation and genetic diversity compared to the novel coronavirus that is causing the current pandemic. The authors wrote that the genome of SARS-CoV-2 is relatively stable, indicating that an easier control is possible, since less susceptibility to mutation expedites the development of antiviral drugs and vaccines.
As an example, the genes that code for the spike protein of the virus stayed relatively the same. This protein is the part of the virus that allows it to attach onto human cells. After analyzing one of the SARS-CoV-2 samples from India last January 27, apparent evidence of the first significant mutation has been demonstrated.
The mutation seems to have a lesser ability to bind to the ACE2 human cell receptor. According to the authors, this discovery raises an alarm on a possible futile attempt for vaccine development in future outbreaks, should more mutations arise.
The research team noted that with additional genomic data being accumulated from the virus' rapid and continuous spread worldwide, the dynamics of its mutation and evolution will have to be closely monitored. The authors added, this is due to the fact that despite the relatively low rate of mutation, novel mutation that has varied immune characteristics and virulence still emerged.
University of Sussex immunology lecturer Jenna Macciochi, who was not involved in the study, explained that viruses have an adaptation period after entering a new host, and since it currently spreads relatively easily, it experiences lesser selective pressure to dramatically mutate.
She added that small mutations are always expected with viruses. The reduced ACE2 binding means less virulence, and this potentially means a lesser capacity to infect.
Nonetheless, But Macciochi noted that since the report is an isolated case, it does not necessarily follow that efforts for a vaccine may be futile. Macciochi states that since the study has not undergone peer review and only had a small sample size, its significance could be limited.
As of writing, Johns Hopkins University reports that over 1.9 million cases have already been recorded worldwide, with nearly 121,000 deaths and almost 465,000 recoveries. The Statista website shows how the virus has already reached all continents except for Antarctica.