Impact of HIV on genomic variability in the 5'UTR of HCV in Indian patients with HCV/HIV co-infection.

Background: The impact of HIV on hepatitis C virus (HCV) genome during HCV/HIV co-infection is poorly understood. The present study was intended to unveil nucleotide sequence variability in the 5'-untranslated region (5'UTR) of HCV in co-infected cases.

Methods: Automated nucleotide sequencing of the 5'UTR of HCV from both mono- and co-infected cases was performed.

Results: Data analysis revealed deletion of a continuous stretch of 12 nucleotides (nt 240-251) from domain IIIc in 20% co-infected cases, but no long-stretch deletion was observed in HCV from mono-infected cases. On the contrary, there was no insertion in the 5'UTR of HCV from co-infectedcases, but there were insertions in domain II and III (3 mononucleotides and 2 dinucleotides) of the 5'UTR in mono-infected cases.

Conclusion: Since domain III is known to be important for binding of 40S ribosomal subunit, deletion of a single stretch of 12 nucleotides in HCV from co-infected cases observed in the present study may have implications during HCV replication with or without HIV infection. Although this is the first report on genomic heterogeneity in the 5'UTR of HCV from HCV/HIV co-infected Indian patients, it would be worthwhile to study if similar changes are observed in other genes of HCV during co-infection.