The possibility of integration of SARS-CoV-2 virus into the human genome

Izvješća o produljenoj detekciji RNA teškog akutnog respiratornog sindroma koronavirusa 2 (SARS-CoV-2) i o kontinuiranim pojavama PCR-pozitivnih testova kod pacijenata mnogo tjedana nakon oporavka od bolesti COVID-19, dovela su u pitanje mogućnost da se RNA virusa SARSCoV-2 može prepisati reverznom transkripcijom i ugraditi u DNA ljudskih stanica. Zhang i sur. (2021) istražili su mogućnost bi li transkripcija ugrađenih sekvenci mogla objasniti neke od pozitivnih PCR testova viđenih kod pacijenata. Otkrili su da se kopije sekvenci DNA SARS-CoV-2 mogu ugraditi u genom zaraženih ljudskih stanica i dokaze koji upućuju na to da se veliki dio virusnih sekvenci prepisuje iz ugrađenih sekvenci DNA, stvarajući ljudsko-virusne kimerne transkripte. Parry i sur. (2021) i Smits i sur. (2021.) smatrali su potrebnim pomnije razmotriti predstavljene dokaze. Pokazali su da su podaci neprikladno interpretirani i ponovno su analizirali objavljene podatke. Nisu našli dokaze za genomsku ugradnju virusa, unatoč dokazanoj prisutnosti predloženog mehanizma. Činjenica da se retrotranskripcija i ugradnja SARS-CoV-2 u genom kod pacijenata događa u značajnoj učestalosti ili čak uopće, ostaje malo vjerojatna.There have been reports about prolonged detection of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) RNA and recurrence of PCR-positive tests in patients many weeks after recovery from COVID-19. This raised the possibility that SARS-CoV-2 RNAs can be reversetranscribed and integrated into the DNA of human cells. Zhang et al. (2021) investigated possibility whether transcription of the integrated sequences might account for some of the positive PCR tests seen in patients. They found that DNA copies of SARS-CoV-2 sequences can be integrated into the genome of infected human cells and evidence suggesting that a large fraction of the viral sequences are transcribed from integrated DNA copies, generating viral–host chimeric transcripts. Parry et al. (2021) and Smits et al. (2021) felt necessary to scrutinize the evidence presented. They showed that the data has been inappropriately interpreted and they reanalyzed published data. They found no evidence for genomic integration of the virus, despite demonstrated availability of the proposed machinery. The fact that retrotranscription and integration of the SARS-CoV-2 genome happens in patients at any notable frequency, or even at all, remains unlikely