https://www.dailymail.co.uk/news/article-10542309/Fresh-lab-leak-fears-study-finds-genetic-code-Covids-spike-protein-linked-Moderna-patent.html
Fresh suspicion that Covid may have been tinkered with in a lab emerged today after scientists found genetic material owned by Moderna in the virus's spike protein.
They identified a tiny snippet of code that is identical to part of a gene patented by the vaccine maker three years before the pandemic.
It was discovered in SARS-CoV-2's unique furin cleavage site, the part that makes it so good at infecting people and separates it from other coronaviruses.
The structure has been one of the focal points of debate about the virus's origin, with some scientists claiming it could not have been acquired naturally.
The international team of researchers suggest the virus may have mutated to have a furin cleavage site during experiments on human cells in a lab.
They claim there is a one-in-three-trillion chance Moderna's sequence randomly appeared through natural evolution.
But there is some debate about whether the match is as rare as the study claims, with other experts describing it as a 'quirky' coincidence rather than a 'smoking gun'.
WHAT IS THE FURIN CLEAVAGE SITE?
SARS-CoV-2, which causes Covid, carries all the information needed for it to spread in around 30,000 letters of genetic code, known as RNA.
But it is the only coronavirus of its type to carry 12 unique letters that allow it to be activated by a common enzyme called furin.
This in turn makes the virus better at invading neighbouring cells.
The so-called furin cleavage site is located on the virus' spike protein, the structure that binds to human cells in the first place.
Scientists sometimes add this element to lab viruses to make them more infectious, but in nature, pathogens can acquire it by swapping genetic code with other members of their family.
The furin has been the focal point of intrigue for many scientists studying the origins of the virus because no other known member of Covid's family - a group called Sarbecoviruses - have the site.