医用诊断X射线工作者GPA基因突变频率与累积受照剂量关系的研究

Relationship between mutation frequency of GPA locus and cumulative dose among medical diagnostic X ray workers

目的 探讨GPA基因突变频率检测作为累积受照生物剂量计的可行性。方法 用改进的GPA基因位点突变检测技术 ,分析了 5 5名不同时期开始X射线工作者和 5 0名非放射科医务工作者外周血红细胞GPA基因突变变异体频率与开始工作时期、工龄和累积受照剂量间的关系。结果 医用X射线工作者的GPA基因突变频率明显高于对照 ;突变率明显增高是发生在 1970年前开始X射线工作者 ,这与肿瘤流行病学调查所见恶性肿瘤危险明显增高发生在 1970年前开始X射线工作者相一致 ;X射线工作者的GPA基因突变频率随累积剂量而增高 ,剂量 效应关系N突变优于NN突变。结论 用GPA基因突变检测作为生物剂量计 ,还有许多问题需要解决 ,如 :个体差异、特异性及剂量

Objective\ To explore the feasibility of using GPA locus mutation assay as a biodosimeter for occupational exposure to ionizing radiation. Methods\ An improved technique of GPA locus mutation assay was used in the study.The frequencies of mutant RBC in peripheral blood of 55 medical X ray workers and 50 controls employed in different calendar\|year periods were detected.The relationship between mutation frequencies (MFs) and period of entry,working years and cumulative doses were analyzed. Results\ The MFs were significantly elevated among X ray workers employed before 1970.This finding is similar to the result of cancer epidemiological study among medical X ray workers,in which the cancer risk was significantly increased only X ray workers employed before 1970.The MFs of GPA increased with increasing cumulative dose.The dose\|effect relationship of N MF with cumulative dose was closer than that of NN MF. Conclusion\ There are many problems to be solved for using GPA MF assay as a biodosimeter such as individual variation,specificity and calibration curve of dose\|effect relationship.\;