Patients with X-ALD, caused by mutations in ABCD1, the transporter responsible for peroxisomal import of straight-chain VLCFAs, often develop the severe cerebral form of the disease between ages 3 and 10, with rapid progression and neuroinflammation (Engelen et al., 2012). The gene discussed is ABCD1; the disease is X-linked adrenoleukodystrophy.