Paleovirology

Source: Wikipedia, the free encyclopedia.

Paleovirology is the study of viruses that existed in the past but are now extinct. In general, viruses cannot leave behind physical fossils,

endogenous retroviruses, or ERVs,[4] and most viral fossils are ERVs. They may preserve genetic code from millions of years ago, hence the "fossil" terminology, although no one has detected a virus in mineral fossils.[2] The most surprising viral fossils originate from non-retroviral DNA and RNA viruses
.

Terminology

Although there is no formal classification system for EVEs, they are categorised according to the taxonomy of their viral origin. Indeed, all known viral genome types and replication strategies, as defined by the Baltimore classification, have been found in the genomic fossil record.[5][6] Acronyms have been designated to describe different types of viral fossil.

Other viral fossils originate from DNA viruses such as

hepadnaviruses (a group that includes hepatitis B).[10]

Resurrection

Successful attempts to "resurrect" extinct viruses from the DNA fossils have been reported.[11] In addition, Pithovirus sibericum was revived from a 30,000-year-old ice core harvested from permafrost in Siberia, Russia.[12][13]

See also

References