I think it's the HIV 'backbone' in this case which is supposed to be the giveaway sign of gain of function craft at work. Confirms it's a hybrid virus modified by lab, not a naturally evolved virus.

So they'll tell the sheep it happened by backflipping into an AIDS patient and doing a tango and waltz on the way to infecting the rest of the world with 'natural' AIDS/Covid voodoo.

For me, this is why all the freedom of info requests go nowhere. There may be a virus, it may be sequenced, but if it was and it is then they couldn't show us because that would confirm 1. It's manufactured in a lab 2. It likely has a patent holder. 3. Other bad shizzle, likely Fau-xi's fault.