姐妹染色单体互换(Sister Chromatid Exchange简称SCE)最早由Taylor等人用放射自显影研究植物染色体时发现。近年来,由于Latt等发现了5-溴脱氧尿嘧啶核苷(BrdU)能区分姐妹染色单体,从而又有了新的发展。目前认为SCE能反映环境因素对机体DNA的损伤。故可利用SCE作为突变形成的指标。SCE分析方法较染色体畸变分析敏感、简单、迅速,甚至能反映数微毫克量的致突变物。但关于健康成人SCE的正常值,国内外各家学者 Sister Chromatid Exchange (Sister Chromatid Exchange referred to as SCE) was first discovered by Taylor et al. Using autoradiography to study plant chromosomes. In recent years, new developments have been made as Latt et al. Found that BrdU can distinguish sister chromatids. At present, SCE can reflect the environmental factors on the body of DNA damage. Therefore, SCE can be used as an indicator of the formation of mutations. SCE analysis is more sensitive, simple and rapid than chromosomal aberration analysis and can even reflect micrograms quantities of mutagens. However, the normal value of healthy adult SCE, scholars at home and abroad