Arginine is present, even as a dimer, in the viral polybasic furin cleavage sites, including that of SARS-CoV-2 in its protein S, whose acquisition is one of its characteristics that distinguishes it from the rest of the sarbecoviruses. The CGGCGG sequence encodes the SARS-CoV-2 furin site RR dimer. The aim of this work is to report the other SARS-CoV-2 arginine pairs, with particular emphasis in their codon usage. Here we show the presence of RR dimers in the orf1ab related non structural

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... ins nsp3, nsp4, nsp6, nsp13 and nsp14A2. Also, with a higher proportion in the structural protein nucleocapsid. All these RR dimers were strictly conserved in the sarbecovirus strains closest to SARS-CoV-2, and none of them was encoded by the CGGCGG sequence.