The Genetic Basis of X-Ray Induced Recessive Lethal Mutations

induced recessive lethals have been visualized as resulting from to the proportion of such lethals associated with chromosomal breakage and the proportion produced independently of breakage. Although it is possible all three types of lethals occur at or near points on chromosomes that have been broken, only point mutation would seem to be capable of arising without chromosomal breakage as a prerequisite. LEA and CATCHESIDE (1945) and HERSKOWITZ (1946) have analyzed the available data and concluded U.