The first commercially available gamma H2AX Pharmacodynamic assay kit has been developed for the study of double strand DNA breaks through the detection of gamma H2AX. H2AX is a phosphorylated histone historically proven as a highly specific and sensitive molecular marker for double strand DNA damage detection. The 96-well non-radioactive ELISA assay documents differences in gamma H2AX levels in peripheral blood mononuclear cells, cultured cells, and tissue biopsies and is available as a complete reagent kit with chemiluminescent detection. AMSBIO