BDNF and Cognitive impairment: Regarding Alzheimer’s disease, there are conflicting reports, but one of the recent reports in JAMA Neurology indicates that in dominantly inherited Alzheimer’s disease (DIAD), the clinical stage of disease and BDNF Met66 are associated with cognitive impairment and the level of site-specific tau phosphorylation, which plays a key role in the pathophysiology of Alzheimer’s disease [37].