Genetic susceptibility biomarkers in studies of occupational and environmental cancer: methodologic issues.

When using biomarkers to assess genetic susceptibility for cancer risk, the following issues should be recognized: (i) exposure assessment should receive as much attention as marker measurement; (ii) it is critical to study cases with a wide range of exposure patterns; (iii) each approach to evaluating susceptibility has its own potential biases; (iv) it is important to demonstrate the biologic plausibility of gene-exposure interactions detected in epidemiologic studies.