The furin cleavage site, with an arginine doublet (RR), is one of the clues of the SARS-CoV-2 origin. This furin-RR is encoded by the CGG-CGG sequence. Because arginine can be encoded by six codons, in a previous work we found that in SARS-CoV-2, CGG was the minority arginine codon (3%). Also, analyzing the RR doublet from a large sample of furin cleavage sites of several kinds of viruses, we found that none of them were encoded by CGG-CGG. Here, we come back to the core of the matter, but from the perspective that in the human genome, in contrast, CGG is the majoroty arginine codon (21%). Here, we highlighted that the 6 arginine codons provide genetic markers to a traceability on the RR origin in the furin site, as well as, to weigh the probability of the theories about the origin of the virus.