Several processes or insults can induce damage on DNA; such as a cell death pathway activation or by the genotoxic activity of a compound; substances that makes them harmful to the genetic information contained in organisms. Genotoxins are the substances that have the property of genotoxicity. All new chemical entities in the drug discovery process include the study of their capacity to act as genotoxins. DNA Damage Assay from Innoprot comprises the use of an antibody for phosphorylated H2AX. A member of the histone H2A family, H2AX, becomes extensively phosphorylated on serine-139 within 1-3 minutes of DNA Double-Strand Breaks (DSB) and forms foci at break sites. We incubate the cells with test-compounds measuring then the number of focis respect to control with the Cell Insight CX7 HCS platform.