Longitudinal changes in plasma NfL levels were similar in A + CU (1.22 pg/mL/year), A + SCD (1.40 pg/mL/year), and A + MCI (1.54 pg/mL/year) individuals (slope A + SCD vs A + CU, p = 0.790; slope A + SCD vs A + MCI, p = 0.790) in a linear mixed model adjusted for age and gender, given the known association of age and NfL levels [33], indicating a similar axonal turnover rate across the pre-dementia AD continuum (slope A + CU vs A + SCD vs A + MCI, p = 0.765). This evidence concerns the gene NEFL and Schnyder corneal dystrophy.