Some studies using in vivo biomarkers for Alzheimer’s pathology have found similar results, such as stronger associations between hippocampal volume and cognition compared with CSF amyloid,21 neurodegeneration measured by 18-F-fluorodeoxyglucose (FDG) PET being a stronger predictor of cognition than amyloid PET22 and atrophy attenuating the effects of CSF amyloid and tau on cognition.23 These in vivo measures of Alzheimer’s disease offer important information during life. The gene discussed is MAPT; the disease is early-onset autosomal dominant Alzheimer disease.