And since biologists already know which part of the genome makes which peptide, this approach immediately shows whereabouts in the genome the mutation is.

ECONOMIST: Viruses

The second thing the team did was to introduce a genetic mutation into the genome of the young egg that allowed for the production of a growth factor, a kind of protein, that can only come from the paternal genome but is vital for normal embryonic development.

ECONOMIST: A ��virgin birth�� in mice