Pseudoxanthoma elasticum (PXE) is an ectopic calcification disorder caused by biallelic mutations in the ABCC6 (ATP-Binding Cassette, subfamily C member 6)–and in rare cases the ENPP1 (Ectonucleotide Pyrophosphatase/Phosphodiesterase 1)–gene (Nitschke et al., 2012; Nitschke and Rutsch 2012). The gene discussed is ENPP1; the disease is Pseudoxanthoma elasticum.