Table 2. Spontaneous revertant frequencies of unc-58(e665).

unc-58(e665) background	Trial	Plates with revertants/total plates	Mutation frequency ± SEM
Wild type	1	0/40	7.06 × 10−7 ± 7.06 × 10−7
	2	1/38
	3	0/39
	4	0/36
sws-1	1	2/41	2.00 × 10−6 ± 1.26 × 10−6
	2	0/40
	3	0/37
	4	1/39

unc-58 reversion assay was carried out as described in Materials and Methods. A plate was scored as having a reversion event if it contained wild-type moving worms. Mutation frequency was calculated by dividing the proportion of plates with reversion events by the number of haploid genomes per plate. The data are presented as the mean mutation frequency ± SEM for four trials.