Retrovirus

Retroviruses are a family of viruses named for their ability to reverse transcribe genetic material from RNA to DNA. They are important in the study of gene expression, molecular genetics, and molecular evolution, and are also implicated in some cancers and AIDS. Retroviruses are composed of an RNA genome surrounded by a protective protein capsid and sometimes an additional envelope of lipids. Retroviruses can infect both animal and plant cells, allowing for the transfer of genetic material between species. They have been used to create genetically engineered animals, plants, and even human cell lines.