Drake (2)
reported a mutation rate to loss of function of gene cI of 2.0 ´ 10-5 per strand copying, based on previous work (1). Screening of over 300 cI null mutants showed that ca.
5% were to amber codons (2). The number
of possible substitutions leading to amber codons in the cI gene is Ts = 38.
Therefore, ms/n/r
=3 ´
2 ´
10-5 ´
0.05 / 38 = 7.9 ´ 10-8.
1. Dove, W. F. 1968. The
genetic of the lambdoid phages. Annu.
Rev. Genet. 2:305-340.
2. Drake, J. W. 1991. A constant rate of spontaneous mutation in DNA-based microbes.
Proc. Natl. Acad. Sci. USA 88:7160-7164.