Three somatic genetic biomarkers and covariates in radiation-exposed Russian cleanup workers of the chernobyl nuclear reactor 6-13 years after exposure.

Biology and Biotechnology Research Program, Lawrence Livermore National Laboratory, California 94550, USA.
Radiation Research (Impact Factor: 2.91). 11/2002; 158(4):424-42.
Source: PubMed


Three somatic mutation assays were evaluated in men exposed to low-dose, whole-body, ionizing radiation. Blood samples were obtained between 1992 and 1999 from 625 Russian Chernobyl cleanup workers and 182 Russian controls. The assays were chromosome translocations in lymphocytes detected by FISH, hypoxanthine phosphoribosyltransferase (HPRT) mutant frequency in lymphocytes by cloning, and flow cytometic assay for glycophorin A (GPA) variant frequency of both deletion (N/Ø) and recombination (N/N) events detected in erythrocytes. Over 30 exposure and lifestyle covariates were available from questionnaires. Among the covariates evaluated, some increased (e.g. age, smoking) and others decreased (e.g. date of sample) biomarker responses at a magnitude comparable to Chernobyl exposure. When adjusted for covariates, exposure at Chernobyl was a statistically significant factor for translocation frequency (increase of 30%, 95% CI of 10%-53%, P = 0.002) and HPRT mutant frequency (increase of 41%, 95% CI of 19%-66%, P < 0.001), but not for either GPA assay. The estimated average dose for the cleanup workers based on the average increase in translocations was 9.5 cGy. Translocation analysis is the preferred biomarker for low-dose radiation dosimetry given its sensitivity, relatively few covariates, and dose-response data. Based on this estimated dose, the risk of exposure-related cancer is expected to be low.

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Available from: Irina Evgenievna Vorobtsova, Oct 28, 2015
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    • "[1–5] which have been the gold standard for many years but these assays are costly and can take weeks to conduct. Gene mutation assays such as HPRT [1,6,7] and Glycophorin A [1,6,8,9] have also been used, although these are not usually as accurate as cytogenetics [1] and only work on individuals of the appropriate genotype or gender. Electron paramagnetic resonance has also been used successfully [9]. "
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