中文摘要：

目的探讨ERCC2／XPD基因多态与短波紫外线（UVC）所致细胞DNA损伤与修复的关联。方法构建稳定表达ERCC2／XPDrs13181AA（Lys751）和ERCC2／XPDrs13181CC（Gln751）2种基因型的质粒，转染中国仓鼠卵巢细胞缺陷型UV5，获得稳定表达ERCC2转染细胞系。应用MTT法比较2种不同基因型转染细胞经不同照射强度UVC处理后细胞抑制率的差别；应用改良彗星试验检测各转染细胞经UVC处理后1、3、6、24hDNA损伤修复能力的差异。结果与UV5ERCC2（AA）相比，突变型细胞UV5ERCC2（CC）。对UVC所致DNA损伤更加敏感，细胞存活率降低（P〈0．05）。改良彗星试验结果显示，UV5ERCC2（CC）。细胞DNA损伤程度较UV5ERCC2（AA）严重，且修复UVC所致DNA损伤的能力降低，在20J／m2UVC处理3、6h时点的差异有统计学意义（P〈0．05）。结论ERCC2／XPDrs13181多态c等位基因与UVC所致DNA损伤修复能力下降相关，提示ERCC2／XPDrs13181基因多态性可能在UVC所致DNA损伤修复中具有一定意义。

英文摘要：

Objective To explore the function of ERCC2 / XPD polymorphisms in the repair of DNA damage induced by UVC. Methods Plasmids stably expressing ERCC2/XPD rs13181 AA （Lys751） and ERCC2/XPD rs13181 CC （G1n751） were transfeeted into Chinese hamster ovary cells, and the stable ERCC2 transfeeted cell lines were obtained. MTT assay was used to compare the inhibitory rates of the transfected cells treated with UVC at different irradiation intensity. The DNA damage repair ability of the transfected cells treated with UVC for 1,3,6 and 24 h was detected by modified comet assay. Results Compared with UV5ERCC2（CC）, UV5ERCC2（CVC）） was more sensitive to UVC with decreased cell viability. DNA damage level of UV5ERCC （CC） cells was more serious than UV5ERCC2 （CC）. Conclusion DNA repair capacity of ERCC2/XPD rs13181A allelie is lower than its wild-type, suggesting that ERCC2/XPD polymorphisms play a critical role in UVC-induced DNA damage repair.