We identified the enrichment of TMEM106B in β-mercaptoethanol/sarkosyl-insoluble pellets from white matter plaques isolated from individuals with RRMS by mass spectrometry, and observed increased TMEM106B immunoreactive puncta in human white matter from individuals with RRMS relative to Alzheimer’s disease and non-neurologic controls. The gene discussed is TMEM106B; the disease is early-onset autosomal dominant Alzheimer disease.