ABCD1 and X-linked adrenoleukodystrophy: In this study, we analyzed human fibroblasts from skin biopsy samples of two sibling X-ALD patients with an identical mutation on the ABCD1 gene (c1825G>A); one X-ALD fibroblast was from a patient with CCALD phenotype, and the other X-ALD fibroblast was from a patient with AMN phenotype.