TARDBP and Atrophy: To strengthen the association between TDP-43 transcriptional regulation functions and genes linked to atrophy in FTLD-TDP, we next determined brain-expressed genes with a higher likelihood of being regulated by TDP-43, operationally defined here as having an above-median number of GU repeats, the putative binding site of TDP-43 (Fig. 4D).24 This approach yielded 7792 genes containing higher amounts of GU repeats compared to other brain-expressed genes [GU tetramers, median (range) = 324 (46–11 313); GU pentamers, median (range) = 107 (23–4087); GU hexamers, median (range) = 37 (5–1663)].