Cytogenetic assays for monitoring populations exposed to environmental mutagens

A variety of cytogenetic assays have been used successfully for monitoring populations exposed to environmental mutagens. The traditional chromosome aberration (CA) assay is one of the most useful, and it also predicts cancer outcome on a population basis. However, the sensitivity of this assay requires improvement, and researchers need to understand other factors that influence the expression of CA and health outcome, especially on an individual basis. The sensitivity and specificity of the CA assay are improved with the use of the fluorescence in situ hybridization (FISH) procedure, which employs a variety of chromosome-specific and chromosome region-specific fluorescence probes to elucidate CA. Factors that influence the expression of CA in a population study include inadequate study design, genetic variations in metabolism of chemicals (genetic susceptibility), and lifestyle differences in response to exposure to environmental mutagens (acquired susceptibility). The latter may involve previous or concurrent exposure to environmental mutagens, e.g., cigarette smoking habits.