Abstract: | Monkeypox mutants arising spontaneously or after serial, high multiplicity passage were characterized phenotypically and by restriction endonuclease mapping. Some resemble "whitepox" and variola viruses in several of the markers tested but all are distinguishable phenotypically from these. None resembles "whitepox" viruses in genome structure although near-terminal deletions or symmetrical, terminal rearrangements, relative to parental monkeypox, occurred. "Whitepox" viruses isolated from animals closely resemble variola in both phenotype and genome structure. |