Single-molecule counting of oxidative DNA damage in telomeres from cancer cells

Abstract

We demonstrate for the first time the single-molecule counting of oxidative DNA damage in telomeres from a human cervical carcinoma cell line (HeLa cells). This method exhibits high sensitivity towards oxidative DNA damage with a detection limit as low as 9.3 × 10⁻¹⁷ M and good discrimination capability down to the 0.001% oxidative damage level. Moreover, this method can quantify the number of oxidative damaged bases (34–44) in telomeres in each HeLa cell treated with 1000 μM H₂O₂.