INDUCTION OF A PARTICULAR DELETION IN MITOCHONDRIAL DNA BY X RAYS DEPENDS ON THE INHERENT RADIOSENSITIVITY OF THE CELLS

摘要

We examined whether X radiation induces a particular deletion in the mitochondrial DNA (mtDNA) of the cells of two human squamous cell carcinoma lines with different sensitivity to radiation and in a radiosensitive ataxia telangiectasia (AT) cell line. We used polymerase chain reaction (PCR) to quantify the accumulation of a particular 4977-bp deletion (Delta mtDNA(4977)). PCR products of Delta mtDNA(4977) were detectable after exposure to 10 Gy in the radioresistant squamous cell carcinoma cells, 2 Gy in the radiosensitive squamous cell carcinoma cells and 1 Gy in the radiosensitive AT cells. These observations suggest that ionizing radiation induces the Delta mtDNA(4977) in human cells and that the radiation doses required to induce this deletion reflect the sensitivity of cells to radiation. (C) 1997 by Radiation Research Society. [References: 23]