PHEX and X-linked hypophosphatemia: Deletion of Phex in C–/– and C–/–/F–/– mice (C–/–/Hyp and C–/–/F–/–/Hyp) did not lead to further increased immunoreactivity for BMP and IHH target genes or ALP activity in entheses, suggesting PHEX-specific functions are unlikely to play a dominant role in XLH enthesopathy development.