Proc. Natl Acad. Sci. USA doi:10.1073/pnas.0913586107 (2010)

The genome of a common herpesvirus may hitchhike from one generation to the next on the ends of human chromosomes, and reawaken in an infectious form.

Human herpesvirus-6 infects almost everyone. Peter Medveczky of the University of South Florida in Tampa and his colleagues studied four families in which some members had unusually high amounts of herpesvirus-6 DNA in their blood. The researchers found that the viral genome had inserted into caps called telomeres at the ends of chromosomes.

The viral genomes in parents and their children were identical, suggesting that the DNA is heritable. Treating cells from these families with compounds that stimulate latent herpesviruses also allowed the viruses to infect other cells in culture.