Viruses found within bats in a Laotian cave are more closely related to SARS-CoV-2 than any other known viruses, according to Nature News.
Researchers led by the Pasteur Institute's Marc Eloit captured 645 bats representing 46 species from northern Laos to collect blood and other samples for sequencing and other analyses. As they report in a preprint posted to Research Square, the researchers found 25 bat coronaviruses within 10 different bat species. This included three viruses found within Rhinolophus, or horseshoe bats, that had high similarity to SARS-CoV-2, including to its receptor binding domain.
As Bloomberg notes, their receptor binding domains are more similar to those of SARS-CoV-2 than the RaTG13 virus found in Yunnan Province, China, which was previously the closest match. Eloit and his colleagues further showed that the viruses found in Rhinolophus could bind to human cells, Nature News adds.
"When SARS-CoV-2 was first sequenced, the receptor binding domain didn't really look like anything we'd seen before," the University of Sydney's Edward Holmes tells Nature News.
He adds at Bloomberg that now with additional sampling and sequencing, "we are starting to find these closely related bits of gene sequence" and that "[e]ventually, with more sampling, the natural ancestry of the entire SARS-CoV-2 genome will be revealed."