Table 1

Increased frequency of expansions and contractions in a rad27Δ strain. PCR (20) was performed on individual colonies to determine the percentage of expanded, contracted, or unchanged tract lengths for both CTG-40 and CTG-70 strains in wild-type or rad27Δ backgrounds after growth at 30°C. Expansion or contraction was defined as having ≳30% of the tract expanded or shortened, respectively. Because cells grew for ∼25 generations, a minimum estimate of the expansion rate for therad27Δ CTG-70 strain is 10−2 per colony per generation. Examples of expansions are shown in Fig. 3.

StrainNumber of colonies examinedExpansion (%)Contraction (%)Unchanged (%)
Wild-type CTG-402000.5198.5
rad27Δ CTG-40100181072
Wild-type CTG-701040694
rad27Δ CTG-7046334622