GALC and frontotemporal dementia: However, galactocerebrosidase (GALC) activity, which is required for lysosomal degradation of Hex1Cer and ST, was 64% higher in frontal white matter of FTD-GRN (p = 0.004), and 33% higher in FTD-C9orf72 cases (p = 0.21, not significant), relative to the controls (ANOVA F = 6.94, p = 0.004) (Fig. 5B).