Genetic Effects of Low Dose Radiations in Man and Animals

1.切尔诺贝利灾难后放射性核素的污染：在受污染地区(戈梅尔、霍尼基、布拉金)和未受污染地区(明斯克)测量和鉴定了放射性核素。放射性核素主要集中在蜻蜓老鼠体内，尽管土壤中的放射性核素在减少。鲤鱼和青蛙中也观察到较高的浓度。生态和跨代影响：尽管十年过去了，但果蝇、青蛙和小鼠的染色体畸变率仍然高达事故发生后的水平。它可能是由这些动物体内高浓度的放射性核素引起的，而不是跨代(遗传)效应。实验研究：给果蝇喂食受污染的红莓后，果蝇的体细胞突变(斑点试验)发生率明显升高。人类遗传效应：采集清盘人员和生活在污染地区人群的外周血淋巴细胞，定量检测白血病标志物WT1肿瘤基因的表达水平。在28例血液学异常的患者中，16例WT1基因显著高表达，提示白血球风险较高。未发生血液学改变的清理者和未污染地区(明斯克)的白俄罗斯人中，WT1的表达呈中等高水平，但居住在大阪的49名日本人和26名可卡西亚人的WT1表达水平均无法检测。

1. Contamination of Radionuclides after Chernobyl Catastrophe : Radionuclides were measured and identified in the contaminated area (Gomel, Khoiniki, Bragin) and uncontaminated area (Minsk). Radionuclides, mostly ^<137>, are concentrated in the glasshopper < dragonfly <mole <mouse, although those in the soil are decreasing. High concentration was also observed in carp and frog.2. Ecological and Transgenerational Effects : Chromosomal aberrations still remain in Drosophila, frog, and mouse as high as those just after the accident, although ten years have passed. It may be caused by highly concentrated radionuclides in these animals, rather than transgenerational (genetic) effects.3. Experimental Studies : Significantly high incidence of somatic mutations (spot test) was ditected in Drosophila by feeding contaminated red berry.4. Genetic Effects in Human : Lymphocytes in the peripheral blood were collected from liquidators and people living in the contaminated area, and expression level of WT1 tumor gene, a maker of leukemia, was quantitated. 16 of 28 liquidators with hematological abnormality showed significantly high expression of WT1 gene, indicating a higher risk of leumekia. Some of the liquidators without hematological change and control Belarusian in the uncontaminated area (Minsk) showed moderately high expression of WT1, but all of 49 Japanese and 26 Cocasians living in Osaka showed undectable level of WT1.