ALDH3A2 is a fatty aldehyde metabolizing enzyme, and Aldh3a2‐knockout mice exhibit a decrease in 2‐OH GalCer due to inactivation of FA2H, which synthesizes 2‐OH FAs for 2‐OH GalCer production.19 These correlations further support our hypothesis that decreases in 2‐OH GalCer are associated with the hypomyelination and spastic paraplegia observed in patients with the ELOVL1 mutation. This evidence concerns the gene ELOVL1 and Spastic paraplegia.