We investigated expression of the DNA damage response (DDR)‐associated molecules γH2AX and DNA‐PKcs using immunohistochemistry and western blotting, and senescence‐associated β‐galactosidase in the frontal association neocortex of cases with low levels of Alzheimer‐type pathology (Braak & Braak stage 0–II), and explored their relationship to cognitive impairment in a population‐representative sample from the Medical Research Council's Cognitive Function and Ageing Study cohort. This evidence concerns the gene PRKDC and Cognitive impairment.