Abstract
Mutagen sensitivity, measured in short-term cultures of peripheral blood lymphocytes by cytogenetic endpoints, is an indirect measure for DNA repair capacity and has been used for many years as a biomarker for intrinsic susceptibility for cancer. In this article, we briefly give an overview of the different cytogenetic mutagen sensitivity approaches that have been used successfully to evaluate the biological effects of polymorphisms in DNA repair genes based on a current review of the literature and based on the need for biomarkers that would allow the characterization of the biological and functional significance of such polymorphisms. We also address some of the future challenges facing this emerging area of research.