The present invention includes compositions and methods for treating diseases or disorders associated with pathological calcification or pathological ossification. In certain embodiments, the diseases or disorders are selected from the group consisting of Generalized Arterial Calcification of Infancy (GACI), Idiopathic Infantile Arterial Calcification (IIAC), Ossification of the Posterior Longitudinal Ligament (OPLL), hypophosphatemic rickets, osteoarthritis, calcification of atherosclerotic plaques, PXE, hereditary and non-hereditary forms of osteoarthritis, ankylosing spondylitis, hardening of the arteries occurring with aging, calciphylaxis resulting from end stage renal disease and progeria.