Which genetic disorder is characterized by the excretion of elevated Very Long Chain Fatty Acids (VLCFAs)?

The disorder characterized by the excretion of elevated Very Long Chain Fatty Acids (VLCFAs) is X-linked adrenoleukodystrophy (X-ALD). This condition is primarily linked to a mutation in the ABCD1 gene, which is responsible for the transport of VLCFAs into peroxisomes for breakdown. When this transport mechanism is impaired due to the mutation, VLCFAs accumulate in the body and are eventually excreted through urine. This accumulation is particularly damaging to the adrenal glands and the nervous system, leading to the symptoms associated with X-ALD.

In contrast, the other disorders listed don't specifically involve the excretion of VLCFAs. For instance, phenylketonuria is related to the metabolism of phenylalanine and does not involve VLCFAs. Zellweger Syndrome involves a deficiency in peroxisomal function affecting multiple pathways including but not limited to VLCFAs; however, it does not focus specifically on their elevated excretion like X-ALD. Pompe disease is a glycogen storage disorder involving the accumulation of glycogen due to the deficiency of the enzyme acid alpha-glucosidase and is also unrelated to VLCFA metabolism.

Thus, the