Their findings offer clues as to how the novel coronavirus, known as SARS-CoV-2, is adapting as it spreads from one person to another.
They could also help scientists better target drugs and vaccines to parts of the virus that are more stable over time.
The study, published in Infection, Genetics and Evolution, was led by the University College London (UCL) Genetics Institute.
Scientists analysed the genetic changes in SARS-CoV-2, the new coronavirus causing COVID-19, by screening the genomes of over 7,500 viruses from infected patients around the globe.
They identified 198 mutations that appear to have independently occurred more than once.
Director of UCL Genetics Institute, Francois Balloux, who co-led the research, cautions that there is nothing to suggest that the new coronavirus is mutating faster or slower than expected, or that it is becoming more dangerous.
“We identified a small subset of mutations that seem to happen over and over again in different strains. They might reflect, to some extent, adaptation to the human host.
“But at this stage, I’d really like to clarify that there is no evidence that we are seeing more virulent or more transmissible lineages,” he said.
The small genetic changes identified were not evenly distributed across the virus genome. Some parts had very few mutations – and researchers say those invariant parts of the virus could be prime targets for drug and vaccine development.
“This is really what we’re looking for – these regions which are constrained, and which will offer vaccines and possibly drugs that the virus won’t find an easy way to escape from,” Balloux explained.
Watch more excerpts from the interview in the player above.