Currently the molecular basis for the clinical heterogeneity of X-linked
adrenoleukodystrophy (X-ALD) is poorly understood. The genetic bases for all different
phenotypic variants of X-ALD are mutations in the gene encoding the peroxisomal ATP-
binding cassette (ABC) transporter, ABCD1 (formerly adrenoleukodystrophy protein, ALDP).
ABCD1 transports CoA-activated very long-chain fatty acids from the cytosol into the
peroxisome for degradation. The phenotypic variability is remarkable ranging from cerebral …