Possible role of genetic predisposition in multigeneration carcinogenesis

A peculiar phenomenon in experimental transplacental carcinogenesis is that in certain animal species or strains, and with certain types of carcinogens, a tumorigenic risk is observed not only in the F1 generation but also in subsequent F2 and even F3 generations when only the P generation has been exposed to a carcinogen. Additionally, in many cases specific types of organs end to be involved. The organs involved include ovaries, mammary glands, stomach, lympho- and myelogenic systems, skin and nervous system. Interestingly, little or no such evidence has been found in the liver, respiratory tract or urinary tract. In the light of experimental and human observations, the authors are currently inclined to hypothesize a heritable predisposition to tumour development in organs specific to animal species and strains, or certain families in human cases, for explaining the mechanisms underlying multigeneration transmission of chemical carcinogenicity.