mutation rate

in biotechnology
The frequency (h-1) with which a mutation occurs within a organism or gene. In general, rates of spontaneous mutation vary between one in 10E4 and one in 10E8 per gene per generation, and can be considerably increased by mutagens.
PAC, 1992, 64, 143. 'Glossary for chemists of terms used in biotechnology (IUPAC Recommendations 1992)' on page 161 (