Researchers at a French institute have resurrected an extinct virus from the human genome. Yes, you read it right, they resurrected it from the human genome itself. The virus, dubbed phoenix, is from a class of viruses known as retroviruses which integrate their genome into the host. At a later time, they may get berserk and infect the host. But if they remain intergrated long enough, they get inactivated due to acquired mutations.
Check out this cool research here.