MGP and Pseudoxanthoma elasticum: For example, the observations that Fetuin-A, MGP (Hendig et al., 2006, 2008b), vitamin K (Vanakker et al., 2010), osteogenic makers, and oxidative stress (Pasquali-Ronchetti et al., 2006; Garcia-Fernandez et al., 2008; Hendig et al., 2008a) are altered in the circulation of PXE patients points indirectly to unbalanced homeostasis of multiple organs and tissues.