用FISH技术对忻州事故宫内受照者进行回顾性剂量重建

Retrospective dose estimation for individuals exposed to accidental exposure in uterus with fluorescence in situ hybridization

目的 对忻州事故中宫内受照者＂京＂进行回顾性剂量重建.方法 受照后16年取＂京＂及其母亲＂芳＂的外周静脉血,用常规方法分析非稳定性染色体畸变,用CB法分析双核淋巴细胞微核;用全染色体探针的FISH方法分析染色体易位,参照本实验室建立的全基因组易位率与吸收剂量之间的剂量-效应曲线进行剂量估算.参照＂芳＂的剂量校正系数推算＂京＂在宫内的受照剂量.结果 受照16年后未观察到两位受照者的外周血非稳定性染色体畸变,淋巴细胞微核率在正常范围内.参照本实验室建立的吸收剂量与全基因组易位率之间的剂量-效应曲线,＂芳＂在16年后用FISH方法估算的剂量为0.76（0.41～1.00）Gy,而＂芳＂在事故后短期内估算的生物剂量为2.30（2.07～2.50）Gy,其剂量校正系数为3.03;＂京＂在16年后估算的剂量为0.61（0.44～0.86）Gy,推算＂京＂在宫内受照的剂量为1.85（1.33～2.61）Gy.结论 16年后用FISH方法对宫内受照者进行剂量重建,参照受照母亲的剂量校正系数,可推算出胎儿宫内受照的大致剂量,为临床提供依据.

Objective To reconstruct the absorbed dose for the individual who was accidentally exposed in uterus 16 years ago.Methods Peripheral blood samples were taken from the victim and her mother.The dicentric and centric ring chromosome aberrations were analyzed with conventional method,the micronucleus was observed with cytokinesis-block micronucleus method,and fluorescence in situ hybridization （FISH） with chromosomes 1,2 and 4 painting probes were used for translocation detection.Dose was estimated according to the standard dose-response curves previously established.Results No unstable chromosome aberrations and normal micronucleus frequencies were observed in two persons 16years after the accident.Against the established dose-response curves with FISH,the doses to the mother and her daughter were 0.76 Gy （95% GI 0.41-1.00 Gy） and 0.61 Gy （95% CI 0.44-0.86 Gy）,respectively.Because the biological dose estimated for the mother 1 month after the accident was 2.30 Gy （95% CI 2.07-2.50 Gy）,the dose correction factor was 3.03 for dose estimation 16 years later.The estimated dose in uterus to the victim was 1.85 Gy （95% CI 1.33-2.61 Gy）.Conclusions The estimated dose to the individual accidentally exposed in uterus 16 years ago can be obtained according to the dose correction factor of the mother with FISH method.