The present invention provides an isolated or purified antibody or
antigenically-reactive fragment thereof that specifically binds to a
C-terminal phosphorylated serine in an H2A histone protein and a product
comprising the same. The present invention further provides fusion
proteins comprising the isolated or purified antibody or
antigenically-reactive fragment thereof. Also provided by the present
invention are a method and a kit for determining double-stranded breaks in
DNA. The method comprises contacting a sample comprising H2A histone
proteins with the isolated or purified antibody or antigenically-reactive
fragment thereof and detecting binding of the antibody or fragment thereof
to an H2A histone protein in the sample. The detection of the binding of
the antibody or fragment thereof to the H2A histone protein indicates the
presence of a DNA double-stranded break in DNA.
