title: Quickscan dicentric chromosome analysis for radiation biodosimetry.
abstract: The dicentric chromosome assay (DCA) is the gold-standard assay for accurately estimating unknown radiological doses to individuals following radiological or nuclear accidents. However in a mass-casualty scenario, this assay is not well suited for providing timely dose estimates due to its time- and expertise-intensive nature. In Canada, two approaches are being developed in an attempt to increase triage-quality biological dosimetry throughput. These are 1) increasing the number of trained personnel capable of conducting the DCA, and 2) evaluating alternative biodosimetry approaches or DCA variations. In a recent exercise, a new scoring technique (termed DCA QuickScan) was evaluated as an alternative rapid-scoring approach. Triage-quality conventional DCA and DCA QuickScan analysis were based upon scoring a minimum of 50 metaphase cells or 30 dicentrics by 9-15 scorers across four laboratories. Dose estimates for the conventional DCA were found to be within 0.5 Gy of the actual dose for 83% of the unknown samples, while DCA QuickScan dose estimates were within 0.5 Gy for 80% of the samples. Of the dose estimates falling 0.5 Gy or more outside the actual dose, the majority were dose over-estimates. It was concluded that the DCA QuickScan approach can provide critical dose information at a much faster rate than the conventional DCA without sacrificing accuracy. Future studies will further evaluate the accuracy of the DCA QuickScan method.
authors.affiliation: Atomic Energy of Canada Limited, Chalk River Laboratories, Chalk River, ON, K0J 1J0, Canada.
authors.forename: F N
authors.initials: FN
authors.lastname: Flegal
authors.forename: Y
authors.initials: Y
authors.lastname: Devantier
authors.forename: J P
authors.initials: JP
authors.lastname: McNamee
authors.forename: R C
authors.initials: RC
authors.lastname: Wilkins
mesh_terms: D000465:Algorithms; D001681:Biological Assay / Q000379:methods*; D004307:Dose-Response Relationship, Radiation; D004781:Environmental Exposure / Q000032:analysis*; D006801:Humans; D048629:Micronuclei, Chromosome-Defective / Q000528:radiation effects*; D015162:Micronucleus Tests / Q000379:methods*; D011829:Radiation Dosage; D011874:Radiometry / Q000379:methods*; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity