Genetic damage, from

Genotoxicity studies are required to identify compounds that can induce genetic damage ranging from single point gene mutations to gross alterations of chromosomal structure. Such effects are taken as indicative of the potential to cause cancer or heritable defects in humans. A standard battery of three types of test is recommended ... 

The micronucleus assay may be used not only for the detection of acute but also chronic genetic damage. In mice, chromosomal breakage in bone marrow erythroblasts produces an accumulation of micronuclei in normochromatic erythrocytes in peripheral blood and there is little, if any, selective removal of micronucleated cells from circulation. This is not the case with rats, which limits their usefulness in long-term studies using peripheral blood. 

Although all alkylating agents can cause the kinds of genetic damage just discussed, individual drugs differ from one another in their electrophilic reactivity, the structure of their reactive intermediates, and their pharmacokinetic properties. These differences will be reflected in the spectrum of their antitumor activities and in the toxicities they produce in normal tissues. 

It may have different outcomes ranging from genetic damage to immune responses. This is true of all interactions between chemicals and macromolecules, as will be seen later in this chapter and in chapter 7. 

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