Polymorphisms in the SFRP3 gene, which encodes Frizzled-related protein (FRZB), a secreted antagonist of the WNT signaling cascade, was found to be associated with hip osteoarthritis already in 2004 [6], and mice lacking FRZB have increased susceptibility to OA [7, 8]. Here, FRZB is linked to phosphoglycerides measurement .