PT  - JOURNAL ARTICLE
AU  - LINDA J. KUO
AU  - LI-XI YANG
TI  - γ-H2AX - A Novel Biomarker for DNA Double-strand Breaks
DP  - 2008 May 01
TA  - In Vivo
PG  - 305--309
VI  - 22
IP  - 3
4099  - http://iv.iiarjournals.org/content/22/3/305.short
4100  - http://iv.iiarjournals.org/content/22/3/305.full
SO  - In Vivo2008 May 01; 22
AB  - When DNA damage, whether it is endogenous or exogenous, forms double stranded breaks (DSBs), it is always followed by the phosphorylation of the histone, H2AX. H2AX is a variant of the H2A protein family, which is a component of the histone octomer in nucleosomes. It is phosphorylated by kinases such as ataxia telangiectasia mutated (ATM) and ATM-Rad3-related (ATR) in the PI3K pathway. This newly phosphorylated protein, γ-H2AX, is the first step in recruiting and localizing DNA repair proteins. DSBs can be induced by mechanisms such as ionizing radiation or cytotoxic agents and subsequently, γ-H2AX foci quickly form. These foci represent the DSBs in a 1:1 manner and can be used as a biomarker for damage. An antibody can be raised against γ-H2AX which can therefore be visualized by immunofluorescence through secondary antibodies. The detection and visualization of γ-H2AX by flow cytometry allow the assessment of DNA damage, related DNA damage proteins and DNA repair. γ-H2AX also has other applications in the detection of genomic damage caused by cytotoxic chemical agents and environmental and physical damage, especially in the context of cancer treatment and therapy.