High levels of serum FGF23 are associated with hypophosphataemia-related rickets (91), as well as the autosomal dominant hypophosphataemic rickets (ADHR), which is characterized by mutations of two FGF23 cleavage sites Arg179 and Ser180 and is frequently accompanied by markedly elevated serum ALP, which may reflect underlying liver abnormalities (92). Here, FGF23 is linked to autosomal dominant hypophosphatemic rickets.