In terms of CSF Alzheimer’s disease biomarker group, 19.6% (n = 60) of the patients were cognitively unimpaired non-Alzheimer’s disease control (i.e. A−T− or amyloid negative, tau negative), 8.2% (n = 25) were A+T− (amyloid positive, tau negative), 39.5% (n = 121) were A+T+ (amyloid positive, tau positive) and 32.7% (n = 100) were A−T− (amyloid negative, tau negative) biomarker with CI (cognitive impairment). The gene discussed is MAPT; the disease is early-onset autosomal dominant Alzheimer disease.