LONDON, May 6 (Xinhua) -- Researchers have discovered that a large proportion of the global genetic diversity of SARS-CoV-2 is found in all hardest-hit countries, suggesting extensive global transmission from early on in the epidemic and the absence of single "Patient Zeroes" in most countries, according to a study released Wednesday by the University College London (UCL).
The study, led by the UCL Genetics Institute, analyzed the emergence of genomic diversity in SARS-CoV-2, the novel coronavirus causing COVID-19, by screening the genomes of over 7,500 viruses from infected patients around the globe.
The researchers identified 198 mutations that appear to have independently occurred more than once.
Their findings not only provide clues to how the virus may have spread globally at the early stage of the epidemic, but further establish that the virus only emerged in late 2019, before quickly spreading across the globe, according to a press release from the UCL.
"All viruses naturally mutate. Mutations in themselves are not a bad thing and there is nothing to suggest SARS-CoV-2 is mutating faster or slower than expected. So far we cannot say whether SARS-CoV-2 is becoming more or less lethal and contagious," said professor Francois Balloux from UCL Genetics Institute, co-lead author of the study.
Regarding the small genetic changes, or mutations, identified, they were not evenly distributed across the virus genome. As some parts of the genome had very few mutations, those invariant parts of the virus could be better targets for drug and vaccine development, according to the researchers.
"A major challenge to defeating viruses is that a vaccine or drug might no longer be effective if the virus has mutated. If we focus our efforts on parts of the virus that are less likely to mutate, we have a better chance of developing drugs that will be effective in the long run," said Balloux. Enditem
