C9orf72 and frontotemporal dementia: The overall difference in thalamic volumes compared with controls was smaller than in the two neuropathological studies of thalamus atrophy that have been performed [28–37% in Mann and South, 1993; 46–49% in C9orf72 carriers and ~25% in sporadic FTD due to TDP-43 pathology in Yang et al., 2017], but our measurements were done in vivo on MRI and as close as possible to the diagnosis.