RAPID SCREENING FOR DELETION MUTATIONS IN THE HPRT GENE USING THE POLYMERASE CHAIN-REACTION - X-RAY AND ALPHA-PARTICLE MUTANT SPECTRA

Conditions were devised for the isolation of DNA from single-mutant colonies on dishes, to give reproducible results in the polymerase chain reaction (PCR). Primers for 3 exons of the hamster hprt gene were used in a multiplex reaction to show rapidly whether the mutants carried deletions at these sites. 138 independent mutants were screened in total, some spontaneous and others induced by X-rays or by alpha-particles from plutonium-238. Few deletions were found among the spontaneous set, while 'total' gene deletions formed about half the mutants found after irradiation. At equitoxic doses, little difference in mutant spectrum was found for the X-ray set compared to the alpha-particle set. This rapid technique should be applicable to many instances of comparative mutagenesis.