Serum hepatitis B virus DNA detection with S- and C-region-directed probes

Summary. Developments in molecular biology have offered a wide range of nucleic acid probes to detect the genome of hepatitis B virus (HBV). We have tested the ability of two enzyme-linked (alkaline phosphatase) probes to detect HBV-DNA. These hybridise with the S and C regions of the genome of HBV and are used to determine the clinical significance of detecting the two regions. A total of 66 serum samples from patients at different stages of HBV infection was examined. HBV-DNA was detected with at least one of the probes in 17 (85 %) patients with HBeAg-positive chronic hepatitis, five (26.3 YO) with anti-HBe-positive chronic hepatitis and six (66.6%) with acute hepatitis. Although both probes were able to detect as little as 10 pg/ml (2-86 x lo6 g.E./ml) of a full length HBV-DNA standard, the Cregion-directed probe did not react in one patient with acute hepatitis, two with HBeAgpositive and three with anti-HBe-positive chronic hepatitis. When C-region-directed probes are used for diagnostic purposes, results should always be accompanied by hybridisation with probes directed against other regions showing less variability (e.g. S region).