O-10 - None of the three BANAL viruses carries a furin cleavage site
Even the closest known natural relatives lack the furin cleavage site that SARS-CoV-2 has, so this dataset does not by itself account for that feature’s origin.
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Why this is evidence
H-5 explicitly predicts the furin cleavage site is absent from the natural relatives because it was inserted; H-1 and H-6 must have it arise naturally and so predict, less strongly, that close relatives would sometimes carry one. Favours H-5, though only weakly given how sparsely the sarbecovirus reservoir is sampled.