PEX5 and Zellweger syndrome: The current zebrafish models for peroxisome biogenesis disorders/Zellweger spectrum disorders (e.g., Pex2, Pex5 deficiency) show phenotypes similar to human ZSD patients (e.g., locomotor impairments, feeding difficulties, liver dysfunction, demyelination, early mortality) as well as alterations in fatty acid metabolism (e.g., accumulation of VLCFAs, branched chain fatty acids, reduced ether phospholipid synthesis).