Humans with loss-of-function of NPT2a [1–3] and NPT2c [4, 5] develop renal mineralization, which may manifest during early childhood prior to specific therapy or when inappropriately receiving active vitamin D analogs, but can also occur throughout life . To model these kidney abnormalities, we used 2 months old Npt2a-/- mice [39, 40] placed on a diet containing 0.6% calcium and 0.7% phosphorus (Harlan Teklad TD.2018S).