摘要:The hepatitis G virus (HGV) is a newly discovered RNA virus, which is associated with acute or chronic hepatitis. A survey was conducted in thalassemic patients, intravenous drug users (IVDU) and blood donors aiming to investigate the prevalence of hepatitis G virus (HGV) infection in these groups in Tehran. The presence of HGV RNA in these populations was determined using reverse transcriptase polymerase chain reaction (RT-PCR) of the 5’ non-coding region (NCR) of the virus. One percent of blood donors, 12.9% of thalassemics and 8.8% of the IVDUs, were infected with HGV. Twenty-five percent of HGV positive cases were also positive for HCV and none were positive for HBV-DNA. The greatest proportion of HCV positive cases were seen in IVDU group (67.4%) being the only HIV positive group (8.8%). In conclusion our study showed that HGV infection occurs with relatively intermediate frequency among thalassemics and IVDUs in Iran and a higher rate of HGV-RNA was observed in older IVDUs.