Probably involved in bone and dentin mineralization and renal phosphate reabsorption.
Lymphocytes and fetal brain; not in adult brain, placenta, skeletal muscle and pancreas; not in adult and fetal heart, lung, liver and kidney.
Involvement in disease
Defects in PHEX are a cause of X-linked hypophosphatemic rickets (HYP) [MIM:307800]. HYP is an X-linked dominant disorder characterized by impaired phosphate uptake in the kidney, which is likely to be caused by abnormal regulation of sodium phosphate cotransport in the proximal tubules. Clinical manifestations include skeletal deformities, growth failure, craniosynostosis, paravertebral calcifications, pseudofractures in lower extremities, and muscular hypotonia with onset in early childhood. X-linked hypophosphatemic rickets is the most common form of hypophosphatemia with an incidence of 1 in 20000.