|SREL Reprint #2407|
Quality Control in the Application of Flow Cytometry to Studies of Environmentally-Induced Genetic Damage
Clark D. McCreedy,1 J. Paul Robinson,2 Cham E. Dallas,3 and Charles H. Jagoe4
1Extension Scientist, School of
Forest Resources, Purdue Univ., W. Lafayette IN 47907
ABSTRACT: Flow cytometry (FCM) has been used to demonstrate altered DNA content in fish, reptiles, birds and mammals exposed to radionuclides, PAHs and other contaminants. However, artifacts resulting from sample preparation, handling, variations in instrument parameters or other factors may confound such measurements. Some artifacts resemble genotoxic responses and so could lead to erroneous positive conclusions. As part of ongoing studies of effects of various pollutants on DNA content in fishes, we tested sample handling and preparation methods for the induction of artifacts. We describe QA/QC methods, including control of staining conditions, doublet discrimination by comparison of peak versus integral fluorescence, internal DNA standards, and the use of time versus fluorescence plots. Consistent application of these practices is essential to obtain valid measurements of DNA content in environmental samples, and neglect of these can result in poor quality data and the acceptance of incorrect hypotheses.
KEYWORDS: quality control, quality assurance, flow cytometry, DNA content, aneuploidy, light scatter, fluorescent staining, artifacts
SREL Reprint #2407
McCreedy, C.D., J.P. Robinson, C.E. Dallas, and C.H. Jagoe. 1999. Quality control in the application of flow cytometry to studies of environmentally-induced genetic damage. p. 401-412. In Environmental Toxicology and Risk Assessment: Standardization of Biomarkers for Endocrine Disruption and Environmental Assessment: Eighth Volume, ASTM STP 1364, edited by D.S. Henshel, M.C. Black, and M.C. Harrass. American Society for Testing and Materials. West Conshohocken, PA.