The pathogenic potential of endogenous retroviruses:: facts and fantasies

Endogenous retroviruses are descendants of viruses that became cellular genes by integration into their host's genome. They still contribute to pathogenicity as a partner in recombination events, by de novo insertion after mobilization followed by activation of downstream protooncogenes, or by gene disruption. Reexpression of viral proteins accompanied by loss of immune tolerance could induce immune disturbances.