Fig. 5.

Proportion of mutants with large deletions and alterations throughout the shuttle vector. Shuttle vector DNA from 5 to 10 mutants isolated from approximately 3 clones for each shuttle vector was digested with AvaI and BglII restriction enzymes for 2 hr at 37°C. Reactions were run on an 0.8% agarose gel. A representative image is shown in panel A. The + indicates an abnormal digest pattern. B, the percent of mutant DNA exhibiting a wild type digest pattern (grey bars) or an abnormal digest pattern (black bars) was calculated as a function of total mutant vectors that were digested. All mutants isolated from the same clone were considered independent (see Materials and Methods). p-values calculated from Fisher’s exact test.