Amyloidosis Cutis Dyschromica (ACD, OMIM #617920) is a rare autosomal recessive or dominant disorder caused by Glycoprotein Non-Metastatic b (GPNMB) gene mutation, and characterized by clinically diffuse speckled hyper-/hypopigmentation and pathologically dermal amyloid deposition. Here, GPNMB is linked to amyloidosis cutis dyschromia.