在正常的细胞中 ,如发生畸变型复制、受到代谢过程中产生的活性氧攻击或机体暴露于电离和紫外辐射等环境因素时 ,细胞内染色体的修饰作用增加。如果不对畸变加以修复 ,DNA的复制错误和染色体损伤会引起导致细胞功能丧失或死亡的永久性基因改变 ,也就是基因突变。纠正自发突变和 In normal cells, such as aberrant replication, reactive oxygen species generated during metabolic attack or environmental exposure to ionizing and ultraviolet radiation and other environmental factors, the modification of intracellular chromosome increases. Without distortion, DNA replication errors and chromosomal damage can cause permanent genetic changes, known as mutations, that lead to loss of function or death of cells. Correct spontaneous mutation and