GALC and Krabbe disease: Loss-of-function mutation in the enzyme galactocerebrosidase (GALC) in GLD leads to an accumulation of galactosylsphingosine (“psychosine”), which is known to contribute to the hallmarks of GLD neuropathology, including neuroinflammation and demyelination (Santambrogio et al., 2012; Potter et al., 2013).