OCA2 and early-onset autosomal dominant Alzheimer disease: In 2011, the National Institute of Neurological and Communicative Disorders and Stroke and the Alzheimer's Disease and Related Disorders Association revised the diagnostic criteria for AD to include Aβ40, Aβ42, Aβ42/Aβ40, t‐tau and p‐tau as CSF biomarkers.39, 40