PEX2 and peroxisome biogenesis disorder: When seen in cases with other PBD-ZSD variants, the clinical severity of the PEX2R119* variant varies based on the other allele, with findings of mild PBD-ZSD with PEX2R119*/ PEX2E55K and findings of mild PBD-ZSD manifesting as childhood-onset cerebellar ataxia and an axonal sensorimotor polyneuropathy with PEX2R119* and a 1-bp insertion (c.865_866insA;170993.0006) in the PEX2 gene (Shimozawa et al., 1999; Mignarri et al., 2012).