MAPT and Alzheimer disease: Analysis of retinal pS396+ tau was performed in a cohort consisting of donors with MCI (n = 9, mean age 89.67 ± 5.15 years, 5 females/4 males), AD (n = 25, mean age 86.80 ± 8.25 years, 16 females/9 males), and NC controls (n = 15, mean age 84.33 ± 8.96 years, 6 females/9 males).