ABSTRACT
Neonatal adrenoleukodystrophy (ALD) was first described in 1978 by H. Ulrich and colleagues. The clinical picture of neonatal ALD is dominated by extreme hypotonia and a severe convulsive disorder. The advent of molecular understanding of the disorders of peroxisomal biogenesis may ultimately render the earlier distinct clinical phenotypes obsolete. Biochemical tests are supplemented with functional studies in cultured fibroblasts, and by molecular analysis. It is clear that peroxisomal fission disorders may be elucidated in patients with normal levels of peroxisomal metabolites. All of the disorders of peroxisomal biogenesis are transmitted in an autosomal recessive fashion. Peroxisomal biogenesis requires the synthesis of proteins on cytosolic polyribosomes and post-translational import to pre-existing peroxisomes, which enlarge until they divide and form new peroxisomes. Defective peroxisomal function is manifest in pathways of plasmalogen synthesis, pipecolic acid and phytanic acid metabolism, branched chain fatty acid oxidation and cholesterol metabolism.
