A Novel PEX13 Variant Causes Zellweger Spectrum Disorder with Mild/Intermediate Phenotype and Cystic Leukoencephalopathy

Background/Purpose: Zellweger spectrum disorders (ZSD) are rare autosomal recessive diseases of peroxisome biogenesis. Phenotypic manifestations include severe classic Zellweger syndrome presenting in neonates, as well as milder courses with variable organ involvement and slower progression. Very few patients with PEX13 variants have been identified so far. PEX13 encodes an integral peroxisomal membrane protein, peroxin 13. While not all functions of the PEX13 protein are yet understood, recent studies suggest a role beyond peroxisome biogenesis and an association with mitochondrial function and autophagy pathways.