Top US Scientist Backtracks on ‘Smoking Gun’ COVID Lab Leak Theory

Leading US scientist had claimed that a feature in COVID-19 was ‘smoking gun’ evidence that it was made in a lab.

A Nobel prize-winning American biologist who has been widely cited to support the "lab leak theory of COVID-19's origin in Wuhan" has now said that he overstated the case, reports The Guardian.

David Baltimore, a prominent biology professor, told Bulletin of the Atomic Scientists that part of the coronavirus' genome – the furin cleavage site – was "smoking gun" evidence that the virus had been contained inside a laboratory and then escaped via a leak.

“These features make a powerful challenge to the idea of a natural origin for SARS2,” he had said at the time.

Recently, Baltimore backed off on some of his claims. He told a fellow researcher, the scientific journal Nature, and the LA Times that while he was not misquoted in the Bulletin, he should not have gone to the extent of using the phrase “smoking gun" and was uncertain what the feature in the COVID-19 genome proved about its origin – natural or otherwise.

In an email to the LA Times, Baltimore wrote, “[I] should have softened the phrase ‘smoking gun’ because I don’t believe that it proves the origin of the furin cleavage site but it does sound that way.

“I believe that the question of whether the sequence was put in naturally or by molecular manipulation is very hard to determine but I wouldn’t rule out either origin.”

In a conversation with Nature too, Baltimore clarified his stance, saying: “There are other possibilities and they need careful consideration, which is all I meant to be saying.”

For most of 2020, many credible scientists and experts argued that the novel coronavirus was of natural origin. This was the widely believed theory, pushed by top experts, media, and fact-checkers, who were often found pushing back against the other theory – that the virus did not occur naturally and was a result of human actions.

Since May 2021, there had been growing support to the possibility of the COVID-19 being genetically modified in a Wuhan lab, which has long been the focus of all discussions over the origin of the novel coronavirus.

On Wednesday, 26 May, US President Joe Biden tasked the country’s intelligence authorities to “redouble” efforts for probing the origins of the novel coronavirus.

Citing a US Intelligence report, The Wall Street Journal recently reported that three researchers from the Wuhan Institute of Virology (WIV) had fallen sick as early as Autumn 2019 and had been to the hospital “with symptoms consistent with both COVID-19 and common seasonal illnesses.”

This is noteworthy new information since China has said the first confirmed case only occurred on 8 December 2019. Reacting to the report by WSJ, China’s Foreign Ministry spokesperson Zhao Lijian said it was "totally untrue".