Several fairly rare disorders arise from defective peroxisomal
proteins. Neonatal adrenoleukodystrophy is caused
by a defective integral membrane protein needed for
transport of very-long-chain fatty acids into the peroxisome
for β-oxidation. Accumulation of these fatty acids in
body fluids can disrupt the myelin sheaths in nerve tissue,
causing severe neurologic symptoms. Deficiencies of peroxisomal
enzymes cause Zellweger syndrome that affects
the structure and functions of several organ systems.