SOX10 and multiple system atrophy: Using data derived from both neurologically healthy controls and MSA, we investigated the performances of both DNAmClockMulti and DNAmClockCortical in white matter dissected from the frontal and occipital lobes and cerebellum, as well as from the corpus callosum and sorted oligodendrocyte‐enriched nuclei (SOX10+), and compared them with prefrontal cortex tissue constituting a mix of grey and white matter.