GBA1 and seborrheic dermatitis: For instance, the association of seborrheic dermatitis with PD may originate from the shared genetic polymorphisms of GBA, LRRK2, and PINK1 (Trinh & Farrer, 2013), which play a role in immune changes, lipid metabolism, and homeostasis of brain (Dzamko et al., 2015; Magnusen et al., 2021).