Table 3. Mutations in Unstable Lac⁺ revertants.

Revertant strains (20 total)		Chromosomal mutations in each strain			F’lac plasmid mutations in each strain
Class	Strain ID	SNPs	Indels	Total	SNPs	Indels	Total
Lightly mutagenized (18)	U0, U6, U9, U11, U12, U16, U19	0	0	0	0	0	0
	U1, U8, U14	0	0	0	1	0	1
	U3, U5, U7, U10, U15, U18	1	0	1	0	0	0
	U17	0	0	0	0	1	1
	U2	1	0	1	1	0	1
Moderately mutagenized (2)	U4	2	0	2	0	0	0
	U13	6	0	6	1	0	1