A retrovirus is a type of virus whose genetic material is carried in ribonucleic acid (RNA), instead of deoxyribonucleic acid (DNA). These viruses are unique in that they reproduce by transcribing themselves into DNA, which is then incorporated into the host cell.
Retroviruses are known to lead to certain types of cancers in both humans and animals, as well as a range of viral infections such as HIV.
Some viruses are now being manipulated by scientists to treat previously incurable genetic conditions such as haemophilia and severe combined immunodeficiency by inserting healthy genes into the human genome.
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