TEMPERATURE-SENSITIVE MUTATIONS IN DROSOPHILA MELANOGASTER.: II. FREQUENCY AMONG SECOND CHROMOSOME RECESSIVE LETHALS INDUCED BY ETHYL METHANESULFONATE

Abstract

Recessive lethal and semilethal mutations induced in chromosome 2 by ethyl methanesulfonate were screened for temperature-sensitivity. Mutants which survive at 17 °C but die at 29° were recovered. At 0.005M EMS, 37.5% of the treated chromosomes were found to be lethal or semilethal from which it is estimated that 10.9% of all EMS-induced lethals are ts. This class of conditional lethals promises to be a useful tool in genetic studies.