Molecular hybridization study of plasma hepatitis B virus DNA from different carriers

We have used molecular hybridization techniques to show that hepatitis B virus (HBV) DNA from different individuals may have substantial differences in sequence homology. Seven specimens of HBV DNA were isolated from plasma of different blood donors. Samples were applied as dots to membranes and nick-translated to form probes. Densitometry of the radioautograms showed that hybridization was most extensive with probe prepared from the same specimen. The hybridization bias was statistically significant (P less than .02) and visible to the naked eye. Hybridization to probes that were digested with nuclease S1 before nick translation did not eliminate the bias. Nor was the bias related to the d/y subdeterminants; on the average, 15 other specimens hybridized equally well to probes prepared from HBV with the same or different subdeterminant. Many specimens among 37 other serum samples showed greater or lesser degrees of homology to different probes, as demonstrated by reprobing of samples fixed to nylon membranes.