By scanning through deleted files from a shared database on Google Cloud, a researcher in Seattle has found 13 partial genetic sequences for some of the initial cases of COVID-19 in Wuhan.

The new study, which was presented on Tuesday, backs up previous claims that a range of coronaviruses were circulating in Wuhan before the December 2019 outbreaks connected to animal and seafood markets.

Early Coronavirus Samples Were Deleted From NIH Database

Jesse Bloom, a researcher at the Fred Hutchinson Cancer Center in Seattle, genetic sequences acquired from early coronavirus cases in China were erased from a US National Institutes of Health database. The report claimed that some of the early cases in the Chinese city of Wuhan are genetically distinct from the varieties that later spread to trigger the pandemic.

Bloom said the sequences do not add to the continuing argument over whether the virus transmitted spontaneously from animals to humans or was caused by a laboratory leak.

However, he claims that his investigation indicates that the samples used to explore the origins of the Covid-19 epidemic may be incomplete.

"I recover the deleted files from the Google Cloud, and reconstruct partial sequences of 13 early epidemic viruses," Bloom, who is helping with efforts to follow the genetic changes of the coronavirus, wrote in a pre-print paper posted on bioRxiv.

NIH Admits Deleting The Sequences Per Someone's Request

The National Institutes of Health acknowledged that the sequences were removed in June 2020 at the investigator's request, who submitted them in March 2020, and that this was the usual procedure. Since the beginning of the pandemic, geneticists have been sharing information in databases like this one.

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The World Health Organization has been leading attempts to determine the coronavirus's origins, and in March produced a report stating that, like previous coronaviruses, the virus most likely began in an animal and was then transmitted to humans. Reports theorized that COVID-19 was produced in a lab and then leaked out is the least likely.

"We are aware of this report and, as we repeatedly asked, we hope that all data on early cases will be made available," WHO spokesman Tarik Jašarević told CNN by email.

The missing sequences, according to Bloom, are not a "smoking gun."

According to Bloom, the study did not provide any further compelling evidence favoring either natural zoonosis or lab accident, according to the same CNN report. Rather, it demonstrates that there are more sequences from early in the outbreak that is still unknown. Some of them exhibit mutations that signal that they are evolutionarily older than the Huanan Seafood Market viruses.

Why Did Someone Delete The Database?

Live Science said Bloom was unable to locate a reason for the deletion of the sequences, and his inquiries to both corresponding authors for clarification received no response.

Bloom points out various flaws in his research, including the fact that the sequences are only incomplete and lack information such as a definite date or location of collection, which is critical for tracing the virus back to its source.

Regardless, Bloom believes that digging deeper into historical data from the NIH and other institutions — and piecing together sequences — could assist to build a clearer picture of SARS-origin CoV-2's and early spread without the need for on-the-ground research in China.

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