Novel PHEX gene mutation associated with X linked hypophosphatemic rickets

Introduction: X-linked hypophosphatemia (XLH) is characterized by renal phosphate wasting with hypophosphatemia, short stature, and rachitic manifestations. Clinical Picture: We describe a novel nonsense mutation in exon 3 of the PHEX gene (Glu⁹⁶X (c.286G>T) causing XLH in a mother and daughter of Indian ancestry. The mother was noted to have concomitant vitamin D insufficiency. Conclusion: Our report identifies a novel nonsense mutation in the PHEX gene causing XLH. It also highlights the fact that the presence of concomitant vitamin D insufficiency should not preclude the diagnosis of familial forms of hypophosphatemic rickets, especially if more than one family member is affected.