DNA damage checkpoints are biochemical pathways that delay or arrest the cell cycle
progression in response to the DNA damage. All eukaryotic cells have four phases within
the cell cycle, G1, S, G2, and M, and one outside, ...
DNA damage-dependent activation of the breast and ovarian cancer susceptibility
protein 1 (Brca1) occurs via activation of ataxia
telangiectasia mutated serine-protein kinase(ATM)  or ataxia