MAPT and amyotrophic lateral sclerosis: Additionally, in the same study, low p-Tau levels and p-Tau/t-Tau ratio correlated with clinical measures of disease such as the ALS functional rating scale-revised (ALSFRS-R) score and mini-mental state examination (MMSE), and with MRI measures of reduced white matter fractional anisotropy in the corticospinal tract and prefrontal cortex in ALS subgroups [67].