[Determination of the level of spontaneous damage in human and mammalian cell DNA]

A technique for registration of spontaneous DNA lesions in intact mammalian cells is proposed. Arabinosid cytosine and hydroxyurea were shown to inhibit the repair of gaps spontaneously formed and accumulated in DNA leading to the formation of double-strand DNA breaks and cell death. The rate of spontaneous lesions was different in cells from different animal species and different tissues. A considerable increase in the level of spontaneous lesions was noted with ageing. It is concluded that the level of spontaneous DNA lesions is one of the fundamental biologically important characteristics of a cell.