ACBD5 and X-linked adrenoleukodystrophy: Analogous to X-ALD patients, the only metabolic abnormality thus far identified in plasma was the increased levels of saturated VLCFAs, which was the reason why Ferdinandusse et al. proposed to categorize ACBD5 deficiency in the group of the peroxisomal β-oxidation deficiencies [81,108].