PTPN22 and Osteochondroma: In particular, Inpp5d knockout was associated with an osteoporotic phenotype (58); polymorphism of Ptpn6 caused its impaired function and associated with low bone mass (59); polymorphism of Ptpn22 was linked to atherosclerotic stroke and arterial calcification (60, 61); Abcc3 expression was associated with risk to atherosclerotic plaque (62); Hmga2 was detected in calcified osteochondromas (63); and Pdgfb KO exhibited reduced brain calcification (64).