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Updated: Aug 2, 2026

Application of Laser Micro-irradiation for Examination of Single and Double Strand Break Repair in Mammalian Cells
Published on: September 5, 2017
CHO cell repair of single-strand and double-strand DNA breaks induced by gamma- and alpha-radiations
Abstract:
Neutral and alkaline sucrose gradient sedimentation analysis was used to measure double- and single-strand breaks in the DNA of Chinese hamster ovary (CHO) cells exposed to either gamma- or alpha-radiation. After irradiation, cells were incubated for 15-180 min to test the ability of the cell to rejoin the DNA breaks. Essentially complete rejoining was observed for single-strand breaks induced by gamma- or alpha-doses below 20 krad and for double-strand breaks induced by gamma doses below 60 krad. Approximately 80% rejoining was observed for double-strand breaks induced by alpha doses below 40 krad. At higher doses, the repair system appeared to saturate in such a way that essentially no additional breaks were rejoined.
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