CSF-Pi levels are significantly elevated in patients with SLC20A2-related PFBC (Paucar et al., 2017; Hozumi et al., 2018) and in Slc20a2 homozygous (HO) knockout mice (Jensen et al., 2016; Wallingford et al., 2017). This evidence concerns the gene SLC20A2 and bilateral striopallidodentate calcinosis.