Hande M Prakash, Azizova Tamara V, Geard Charles R, Burak Ludmilla E, Mitchell Catherine R, Khokhryakov Valentin F, Vasilenko Evgeny K, Brenner David J
Center for Radiological Research, Columbia University, New York, NY 10032, USA.
Am J Hum Genet. 2003 May;72(5):1162-70. doi: 10.1086/375041. Epub 2003 Apr 4.
Speculation has long surrounded the question of whether past exposure to ionizing radiation leaves a unique permanent signature in the genome. Intrachromosomal rearrangements or deletions are produced much more efficiently by densely ionizing radiation than by chemical mutagens, x-rays, or endogenous aging processes. Until recently, such stable intrachromosomal aberrations have been very hard to detect, but a new chromosome band painting technique has made their detection practical. We report the detection and quantification of stable intrachromosomal aberrations in lymphocytes of healthy former nuclear-weapons workers who were exposed to plutonium many years ago. Even many years after occupational exposure, more than half the blood cells of the healthy plutonium workers contain large (>6 Mb) intrachromosomal rearrangements. The yield of these aberrations was highly correlated with plutonium dose to the bone marrow. The control groups contained very few such intrachromosomal aberrations. Quantification of this large-scale chromosomal damage in human populations exposed many years earlier will lead to new insights into the mechanisms and risks of cytogenetic damage.
长期以来，人们一直在猜测过去暴露于电离辐射是否会在基因组中留下独特的永久印记。与化学诱变剂、X射线或内源性衰老过程相比，密集电离辐射能更有效地产生染色体内重排或缺失。直到最近，这种稳定的染色体内畸变一直很难检测到，但一种新的染色体带涂染技术使它们的检测变得可行。我们报告了对多年前接触过钚的健康前核武器工作者淋巴细胞中稳定染色体内畸变的检测和定量。即使在职业暴露多年后，健康钚接触者超过一半的血细胞含有大型（>6 Mb）染色体内重排。这些畸变的发生率与骨髓所受钚剂量高度相关。对照组中此类染色体内畸变极少。对多年前暴露人群中这种大规模染色体损伤的定量分析将为细胞遗传学损伤的机制和风险带来新的见解。
