To summarise, a thread on the new preprint.
Two Hungarian bioinformatics experts noticed an odd thing in a genomic database. Soil samples taken on King George's Island, Antarctica in 2018 or 2019 by Chinese scientists included sequences from SARS-CoV-2. 1/7
Two Hungarian bioinformatics experts noticed an odd thing in a genomic database. Soil samples taken on King George's Island, Antarctica in 2018 or 2019 by Chinese scientists included sequences from SARS-CoV-2. 1/7
https://twitter.com/jbloom_lab/status/1491297779855278082
In 3 of the samples there was enough to recover a 17x virus genome. It turns out to be a genome with three mutations that take it closer to the bat relatives, so may be an ancestral version of the virus. 2/7
Nobody is suggesting the virus was in Antarctica. The sequencing was done in Shanghai, by a firm called Sangon Biotech, which is frequently used by lots of labs in China including the Wuhan Institute of Virology. 3/7
So it's almost certainly a case of "barcode misassignment errors" during demultiplexing - a frequent contamination issue with this type of Illumina machine in sloppy sequencing labs. 4/7
The DNA was extracted in December 2019 and the sequencing was done soon after but the date is not certain: maybe in early 2020 by which time lots of virus samples were being tested. So maybe not very interesting after all. 5/7
But 3 things now suggest it might be interesting. First, the unique mutations hint at it being an ancestral variant. Second, when the Hungarians published the preprint, the data was taken off the database by the Chinese scientists who had deposited it, then later restored. 6/7
Third, the two Hungarians have now published a new preprint identifying other animal DNA in the same samples. These are not from seals or penguins, but from African green monkeys and Chinese hamsters. Both species are the source of commonly used laboratory cell lines. 7/7
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