In the experiments reported below, the inner aspects of the pinnae of rabbits' ear~ were treated for 1 hour with the carcinogen 7,1~-dimethylbenzanthracene, 1 per ce~t ~n acetone. Other ears were treated with the nonearcinogen anthracene in aeetone, and still other ears were left untreated. Discs of skin were removed from these ears, and the relative adhesiveness of the epidermal cells was dete...

The incorporation of inorganic phosphate into H1-histones of rat liver was stimulated after the repeated s.c. administration of diethylnitrosamine. This stimulation was observed as early as after the fifth daily injection of the carcinogen and amounts to approximately 3 times the control value on the 60th day of the experiment. The effect was reversible when the application of the carcinogen wa...

Benzo[alpha]pyrene diol epoxide (BPDE) is a well-studied environmental carcinogen that binds covalently to DNA. Here we describe a photochemical technique that allows us to map BPDE-binding sites within cloned gene sequences. The technique is based upon our observation that, when irradiated with laser light at 355 nm, one single-strand DNA cut is produced at each BPDE binding site. In initial e...

Distribution and seasonal variation of sixteen priority polycyclic aromatic hydrocarbons (PAHs) were investigated in the drinking water of Tehran, the capital of Iran. Detected single and total PAHs concentrations were in the range of 2.01-38.96 and 32.45-733.10 ng/L, respectively, which were quite high compared to the values recorded in other areas of the world. The average occurrence of PAHs ...

Deletions and other genome rearrangements are associated with carcinogenesis and inheritable diseases. The pink-eyed unstable (pun) mutation in the mouse is caused by duplication of a 70-kb internal fragment of the p gene. Spontaneous reversion events in homozygous pun/pun mice occur through deletion of a duplicated sequence. Reversion events in premelanocytes in the mouse embryo detected as bl...