A frequent, naturally occurring mutation (P130T) of human hepatitis B virus core antigen is compensatory for immature secretion phenotype of another frequent variant (I97L).

A frequent mutation at codon 97 of human hepatitis B virus core antigen has been shown to cause an "immature secretion" phenotype, featuring nonselective and excessive secretions of virions containing immature viral genome. Our current study demonstrates that this abnormality can be efficiently offset by another frequent core mutation, P130T.