Increased ACOX1 protein and activity in granular keratinocytes of ft/ft epidermis, altered lipid profile in human epidermal equivalents overexpressing ACOX1, and increased ACOX1 immunostaining in skin biopsies from patients with ADL suggest that peroxisomal β-oxidation significantly contributes to lipid signature in ADL epidermis. Here, ACOX1 is linked to activities of daily living score measurement.