ABCC6 and chronic kidney disease: Ectopic or extraskeletal calcification may stem from genetic mutations (e.g., ABCC6, ATP-binding cassette C subfamily member 6 in pseudoxanthoma elasticum; MGP, matrix Gla protein in Keutel syndrome; FAM20A, family with sequence similarity 20 member A in amelogenesis imperfect) [3,4] or from acquired chronic illnesses (e.g., chronic kidney disease, diabetes, atherosclerosis).