While the histological hallmark of neuraxial degeneration with spheroids is common to the three disorders: AARS2 leukoencephalopathy, CSF1R related HDLS/ALSP, and HDLS-S (with the latter two expected to be most closely related), some differences have been observed, including an earlier age of onset of leukodystrophy (third decade of life) in addition to ovarian failure associated to AARS2 mutations [15]. Here, AARS2 is linked to leukodystrophy.