the local fall-out area and that the added hazard due to world-wide distribution of fission products may be of secondary importance. The fundamental facts of radiation genetics as presented by such leading geneticists as H. J. Muller, A. H. Sturtevant, C. Stern, and others, have been generally accepted. 30, 31, 32, 33, 34 These are: 1. Radiation to the gonads will produce mutations in germinal 2. The mutation rate is proportional to the total dose of cells. radiation received and is independent of dose rate. 3. There is no threshold for mutation effect. 4. Mutations are primarily deleterious, and may be classified as follows: . , a. Lethals - dominant. b. Lethals - recessive: c. Deleterious - non-lethal but causing some percentage complete and incomplete. decrease in efficiency. 5. Mutations produced by artificial radiation are the same as those already produced and being produced spontaneously. 6. Genetic death is the removal of a fertilized egg cell, or the individual developing therefrom, before it has a chance to reproduce. Quantitative genetic concepts are derived from experimental Stern, C., Principles of Human Genetics, W.H. Freeman Co., 1950. Muller, H.J., Radiation Damage to Genetic Material, American Scientist, 38, 1950. Sturtevant, A.H., The Genetic Effects of High Energy Irradiation ES of Human Populations, Engineering and Science Monthly of California Institute of Technology, January, 1955. Plough, H.H., Radiation Tolerance and Genetic Effects. 10, 1952. Nucleonics Muller, H.J., The Manner of Dependence of "The Permissible Dose” of Radiation on the Amount of Genetic Damage, Acta Radiologica 41:5, 1954.