TABLE 10.

Nuclear mutations which decrease petite production

Mutation	% of petites in cultures		Reference
	Wild type	Mutant
srm1a (mmg1b)	51.2 ± 5.6	1.1 ± 0.3	66
srm2 (mmg2)	51.2 ± 5.6	0.8 ± 0.3	66
srm3 (mmg3)	51.2 ± 5.6	0.9 ± 0.3	66
srm4 (mmg4)	51.2 ± 5.6	9.3 ± 1.2	66
srm5 = cdc28-srm	30.3 ± 6.1	3.1 ± 0.7	67
srm1	30.3 ± 6.1	1.1 ± 0.2	67
cdc28-srm + srm1	30.3 ± 6.1	0.06 ± 0.03	67
cdc28-1	79.9 ± 12.2	5.1 ± 2.9	162

^asrm means spontaneous rho⁰ mutations. The srm1 to srm4 mutations define four complementation groups. The relevant genes have not been cloned. 

^bmmg means mutability of mitochondrial genome.