Longini would start to seriously worry if the H5N1 mutated to gain an R of 1.7 or higher.

FORBES: Magazine Article

If Sonic hedgehog is mutated when a mouse is growing its paws, the animal won't grow digits.

FORBES: Magazine Article

If one gene is mutated, a duplicate gene may function in its place.

FORBES: Why You Should Fear Giant Databases With Your DNA

If at least one of the newly selected tumours also had a mutated version of one of the genes in question, that gene was reckoned a good candidate as a tumour-causing gene.

ECONOMIST: Cancer genetics