First, we investigated the correlation between the levels of the 49 pre-selected proteins in CSF and CSF levels of t-tau, p-tau, Aβ40, Aβ42, Aβ42/40 ratio and NfL in A+T+ individuals with a diagnosis of probable AD, MCI, or SCD (n=65) and A-T- individuals with SCD (n=106). This evidence concerns the gene NEFL and Alzheimer disease.