ABSTRACT

Recent developments in gene technology have provided us with the ability to target specific genes in the chromosomes of living organisms, thus permitting the construction of specific genetic deficiencies. For example, mice lacking the genetic information for certain types of DNA repair functions have now been produced. These manifest hypersensitivity to DNA-damaging agents, genetic instability, premature senescence, and elevated rates of cancer development, together with defective embryogenesis. Such abnormalities, displayed in DNA repair-deficient animals, attest to the crucial importance of DNA repair systems in protecting organisms from the effects of DNA damage.