Adrenoleukodystrophy (ALD) is an X-linked genetic disorder caused by mutation of the ABCD1 gene, which encodes a peroxisomal membrane transporter protein required to import very-long-chain fatty acids (VLCFAs) into peroxisomes for degradation; loss of this transport function causes intracellular VLCFA accumulation that damages nerve cells, glial cells, adrenocortical steroid-producing cells, and other affected tissues. The disorder exhibits variable expressivity, manifesting as several distinct clinical phenotypes distinguished by the tissue and rate of degeneration — rapidly progressive cerebral demyelination versus slowly progressive peripheral/spinal nerve fiber degeneration versus isolated adrenal insufficiency — illustrating, within medical genetics and neurology, how a single gene defect in a metabolic transport pathway can produce heterogeneous clinical outcomes via X-linked inheritance with sex-dependent penetrance.
Adrenoleukodystrophy (ALD) is an X-linked genetic disorder caused by mutation of the ABCD1 gene, which encodes a peroxisomal membrane transporter protein required to import very-long-chain fatty acid…