X-RAY INDUCED CHROMOSOMAL ALTERATIONS IN DROSOPHILA MELANOGASTER

Abstract

N THE fall of 1936 the first two authors began a series of experiments I to determine the frequency of minute inversions in material treated by X-rays. Before long it was realized that the frequency of such inversions is very low and that a reliable analysis would involve such technical difficulties that it would require a great deal more time than was available to the authors. Therefore, the original plan was revised and a new experiment started to determine the relation between X-ray dosage and the frequency of chromosomal breaks, the distribution of breaks along the chromosomes, and related problems. Subsequently when the experimental part of the problem was well under way the third author joined in the work.