A bit disappointing that so many Bitcoiners fall for random pseudo-science conspiracy bullshit. Just remember when the next time you tell somebody that they are a sheep for not using Bitcoin or hating banks, look in the mirror first. 
Great, we have almost the whole clown car chiming in now.
It is a fact, purposely infecting test animals and selecting for the most virulent mutations would be INDISTINGUISHABLE from natural mutation, because it is nothing more than accelerating a natural process and selecting for desirable traits.
From the abstract cited in your article:
"Site-directed mutagenesis" is NOT a natural process. Convenient how they left that tidbit out.
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...We genetically modified A/H5N1 virus by site-directed mutagenesis and subsequent serial passage in ferrets. The genetically modified A/H5N1 virus acquired mutations during passage in ferrets, ultimately becoming airborne transmissible in ferrets.
"Site-directed mutagenesis" is NOT a natural process. Convenient how they left that tidbit out.
https://international.neb.com/applications/cloning-and-synthetic-biology/site-directed-mutagenesis
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SDM is an in vitro procedure that uses custom designed oligonucleotide primers to confer a desired mutation in a double-stranded DNA plasmid.
There is no evidence that this has been excluded as a possibility, and any claims otherwise are assumptions, not based on observable empirical data.
You really don't understand concepts of proof and evidence. The burden of proof is on you to prove that the virus was created in a lab. It's not anybody's job to prove that its not. Just flinging improbabilities out there and then saying they are likely is nothing but you propelling baseless conspiracy theories.
You like to play this little game a lot, where if I link an article, you expect me to defend every single facet of it as if I said it, and if I don't nothing I say has any logical basis. You keep talking about the article all you like, regardless of whatever is in it or the study it is based on, there is no denying...
IT IS A FACT viruses can have their mutations accelerated in a lab by infecting lots of animal subjects, and selecting for preferable mutation traits. This is NOT something that would be distinguishable from natural mutation. You call me incel, conspiritard, etc. all you like, none of this is an argument or changes this fact.