Uchida I A
Environ Health Perspect. 1979 Aug;31:13-17. doi: 10.1289/ehp.793113.
The methodology and results of epidemiological studies of the effects of preconception diagnostic x-rays of the abdomen on chromosome segregation in humans are described. Many studies have been conducted in a number of different countries. The vast majority show the same positive, though not significant, trend to increased nondisjunction among the offspring of irradiated women. The results of the various studies, however, cannot be pooled because of differing methodologies used. A worldwide co-operative project with standardized methodology is recommended. Such a study should identify the parental origin of the nondisjunctional event before etiological factors are investigated. Abnormal chromosome segregation during mitotic division has been inducted experimentally by the in vitro exposure of human lymphocytes to a low dose of 50 R gamma irradiation. First meiotic nondisjunction has been successfully induced by whole body exposure of female mice to a low dose of radiation. Further experiments are being conducted to try to induce abnormal segregation during second meiotic division. Because of difficulties encountered in trying to estimate total gonad doses resulting from differing techniques employed by radiologists and other health personnel, no attempt has been made to estimate the doubling dose nor minimum safe dose regarding the effects of radiation on chromosome segregation in humans. The question of time-related repair of the mechanism involved in chromosome segregation is raised.
本文描述了关于孕前腹部诊断性X射线对人类染色体分离影响的流行病学研究方法和结果。许多国家都开展了此类研究。绝大多数研究都呈现出相同的积极趋势，即受照女性后代中染色体不分离增加，尽管这种趋势并不显著。然而，由于所采用的方法不同，各项研究结果无法汇总。建议开展一项采用标准化方法的全球合作项目。在研究病因之前，此类研究应确定染色体不分离事件的亲本来源。通过将人类淋巴细胞体外暴露于50伦琴的低剂量γ射线，已实验性诱导有丝分裂期间的异常染色体分离。通过对雌性小鼠全身暴露于低剂量辐射，已成功诱导第一次减数分裂不分离。正在进行进一步实验，试图诱导第二次减数分裂期间的异常分离。由于放射科医生和其他卫生人员采用的技术不同，难以估算性腺总剂量，因此未尝试估算辐射对人类染色体分离影响的倍加剂量或最小安全剂量。文中还提出了与时间相关的染色体分离机制修复问题。
