NRGN and Alzheimer disease: Apart from the classic biomarkers, many other promising biomarkers such as lysosomal proteins, GAP43, neurogranin, SNAP25, and synaptotagmin 1 in NDEs from plasma could predict the development of AD at least 5 years before cognitive impairment and differentiate AD from frontotemporal dementia with 95.8% accuracy (Goetzl et al., 2015a; Jia et al., 2021).