ABCB6 is an ATP-dependent transporter localized to the outer mitochondrial membrane and plasma membrane that functions as a broad-spectrum porphyrin transporter 1. The protein catalyzes bidirectional transport of heme and porphyrin precursors: importing substrates across the outer mitochondrial membrane to support de novo heme biosynthesis and regulating heme-iron homeostasis 2, while also exporting excess porphyrins across the plasma membrane to prevent toxic accumulation 1. ABCB6 influences cellular antioxidant defenses by reducing reactive oxygen species levels, with effects on heme synthesis and ferroptosis regulation 23. ABCB6 mutations cause multiple heritable conditions. Loss-of-function variants cause dyschromatosis universalis hereditaria (DUH), an autosomal dominant disorder characterized by mottled hyperpigmented and hypopigmented skin macules with occasional hearing loss 45. Zebrafish and mouse studies demonstrate ABCB6 developmental roles in inner ear hair cell differentiation and auditory function 5. ABCB6 deficiency also underlies pseudohyperkalemia due to red cell leak and contributes to hereditary stomatocytosis through impaired erythrocyte volume homeostasis 67. Clinically, ABCB6 dysfunction enhances porphyria severity and increases susceptibility to transfusion reactions 1. In cancer, ABCB6 overexpression suppresses ferroptosis through mitophagy-mediated mechanisms, potentially promoting colon cancer progression 3.