In brief, expression of Fig4 in neurons is necessary and sufficient to prevent spongiform degeneration, whereas expression in astrocytes prevents the accumulation of autophagy markers and microgliosis seen in these cells, but has no impact in the neuronal phenotype.170, 171 Taken together, these results imply that autophagic abnormalities play a secondary role in the etiology of CMT4J and that disease therapy should target neurons directly. This evidence concerns the gene FIG4 and Charcot-Marie-Tooth disease type 4J.