Levels of CSF core biomarkers, namely amyloid β1-42 (β42), β1-40 (β40), total tau (T-tau), phosphorylated tau at threonine 181 (P-tau) and amyloid β1-42/ β1-40 ratio (β42/40 ratio), were further evaluated in AD patients. The gene discussed is MAPT; the disease is Alzheimer disease.