Hutchinson F
Radiobiology Laboratories, Yale University, New Haven, CT 06511.
Semin Cancer Biol. 1993 Apr;4(2):85-92.
In mammalian cells, ionizing radiation induces comparable numbers of point mutations (principally base changes, frameshifts and small deletions) and of large deletions of more than a hundred base pairs. The latter are formed either by misrepair of an end from one double-strand break with an end from another, or by a second mechanism which, it is suggested, is initiated by slowly repaired single-strand nicks. The ratio of deletions to point mutations is variable from one gene to another, and is greatest for genes in which very large deletions still allow cells to survive.
在哺乳动物细胞中，电离辐射诱导产生数量相当的点突变（主要是碱基变化、移码突变和小缺失）以及超过一百个碱基对的大缺失。后者的形成要么是由于一个双链断裂的末端与另一个双链断裂的末端错配修复，要么是由于另一种机制，有人认为这种机制是由缓慢修复的单链切口引发的。缺失与点突变的比例因基因而异，对于那些非常大的缺失仍能使细胞存活的基因来说，该比例最大。
