Chromosome breakage by 1-methyl-2-benzylhydrazine in mouse cancer cells.

The induction of chromatid translocations by l-methyl-2-benzylhydrazine was studied in a number of malignant and normal mammalian cell types and in narcissus root cells. In three different mouse ascites tumors (Ehrlich, 2BF, and LI210) treated in vivo, translocations were induced. In the Ehrlich tumor, they were induced with unusually high frequency, involving, in some cells, a majority of the chromosomes. None were found in the Ehrlich tumor or HeLa cells in vitro, nor were any found in untreated controls. No translocations were observed in treated or untreated normal tissues in vivo (mouse bone marrow and spleen, narcissus roots) or in vitro (human lymphocytes, mouse spleen).