Researchers have discovered the third new variant of coronavirus in the United States and say it may end up being the most easily transmitted yet.
A team from Southern Illinois University Carbondale tracked the earliest appearance of a new variant, called 20C-US, to Texas in May 2020.
The variant carries several mutations, including the spike protein, which the virus uses to enter and infect human cells.
Researchers say the variety has not spread significantly outside the country’s borders, and it is most prevalent in the Upper Midwest.
What’s more, it could be responsible for at least 50 percent of all U.S. cases, which means it̵
Researchers predict that 20C-US may be the most dominant variant of coronavirus in the United States at present.
20C-US is now one of the growing list of mutations discovered in countries such as the UK, South Africa and Brazil.
The news comes just a day after researchers in Ohio announced the first discovery of two homemade varieties – one almost identical to a variety that originated in the UK and the other completely unique to the United States and dominant in Columbus’ capital.
Researchers from Southern Illinois University Carbondale have found a third new variant of coronavirus, called 20C-US, first discovered in Texas in May 2020. Image: Odessa Regional Medical Center nurse Teresa Armendariz tests a person for COVID-19 in West Texas Horse Center in Odessa, Texas, December 8
Genome sequencing revealed an increase in the new variant in July 2020 (left), and between November 1 and December 31, it accounted for 50% of all U.S. genomes (right).
The results were published in a pre-printed article on bioRxiv.org on Wednesday.
Led by Dr. Keith Gagnon, associate professor of chemistry and biochemistry at SIU, the team first noticed the possibility of the new variant while looking at genome sequencing data from Illinois.
‘We just looked at our local, like state-specific Illinois data … and we were asked [by the Illinois Department of Public Health] to specifically look for spike protein mutations from the British variant, for example, he told DailyMail.com.
‘When we review the data, we do not see a UK variant, but I still see this large branching of the final genetic tree that we reconstructed.’
Of the viral genome samples taken from March to date, which were sequenced, one variant was more pronounced than the rest.
To see if it was present at the national level, researchers randomly examined 3.3 percent of U.S. genomes available on the global genomic database GISAID.
The earliest appearance was found from a sample taken in the greater Houston area of Texas on May 20, 2020.
After the variant over time, there was a remarkable expansion in the variant’s presence in July 2020, coinciding with America’s second wave of the pandemic in states like Wisconsin and Illinois.
However, between December 50 and 31, nearly 50 percent of all sequenced genomes from the United States are the new variant.
Researchers suggest that this means that 20C-US has ‘surpassed 50 percent penetration to become the most dominant variant in the US’
The variant has not spread significantly outside the United States and is most widespread in the Upper Midwest (above)
Researchers say the virus has several mutations, including two to the spike protein, which it uses to enter and infect cells. The image: CDC illustration of coronavirus
However, it has a high prevalence in the eastern and midwestern regions and does not spread widely to the western half of the United States
‘It is here. We found it. It is certainly home-grown and widespread, and we are the first to characterize it, ‘said Gagnon.
20C-US has been reported in other countries, including Australia, Israel, Mexico, New Zealand, Poland, Singapore, Taiwan and Thailand, but at low levels.
The first mutations that the virus showed were in genes related to the maturation of virus particles – a process by which a virus breaks from a host cell and activates to infect multiple cells – and the treatment of viral proteins.
Gagnon says these are all important for virus production.
Since then, the new variant has formed two new mutations in the spike protein, indicating that it is evolving.
Evidence is lacking, but the team says the combination of reduced deaths and an increase in COVID-19 infections suggests that the new variant is highly transmissible, but only causes a disease in the middle.
Dr. Daniel Jones of Ohio State University Wexner Medical Center, who discovered the Columbus variant, told DailyMail.com that the Illinois variant ‘looks closely related but not exactly identical.’
Jones said this means the two sets of researchers – in Ohio and Illinois – are likely to track variants from the same outgrowth.
With the first doses of newly approved vaccines being administered across the country, Gagnon said it is unknown whether variant will affect its efficiency.
‘Based on the mutations so far, I do not think it will significantly affect the effectiveness of the vaccine,’ he said.
‘The catch is that the virus continues to develop, and since May it has acquired three mutations, two of which are in the tip protein, one of which may affect antibody binding. There are many unknowns. ‘
Both Pfizer and Moderna have tested their vaccines against the international variants and say they expect jabs to provide protection.