Extended Data Fig. 1: Difference distribution curve for baseline (cross-sectional) CSF and serum NfL levels in mutation carriers and non-carriers.

a,b, Difference of posterior distribution for baseline CSF NfL (n = 187) (a) and baseline serum NfL (n = 405) (b) as a function of EYO. The solid red lines depict the median of the difference distribution; the shaded area represents the 99% equal-tailed credible intervals. EYO was considered statistically significant if the 99% equal-tailed credible intervals of the posterior distribution did not overlap 0 (6.8 years before EYO for both baseline CSF and serum NfL). For the absolute values of baseline CSF and serum NfL, see Fig. 1a,b.