Vector

A large DNA or RNA molecule used to transport genetic information into cells. Viral vectors are viruses that have been modified so they no longer multiply and cause disease. Non-viral vectors include plasmids into which specific genetic material has been added.

Virus

A section of DNA or RNA with a protein coat. Viruses are very small and can inject their DNA or RNA into ‘host’ cells, causing the cell to produce more copies of the virus. They can be made harmless by changing their genetic code.