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Novel PHEX mutation associated with hypophosphatemic rickets.
Katharina M Roetzer1, Franz Varga, Elisabeth Zwettler
1Ludwig Boltzmann Institute of Osteology at the Hanusch Hospital of WGKK and AUVA Trauma Centre Meidling, 4th Medical Department, Hanusch Hospital, Vienna, Austria.
Nephron. Physiology
|April 5, 2007
Summary
A novel PHEX gene mutation (177delC) was identified in a patient with X-linked hypophosphatemia (XLH), a common heritable rickets. This finding contributes to understanding XLH pathogenesis.
Area of Science:
- Genetics
- Endocrinology
- Bone Biology
Background:
- X-linked hypophosphatemia (XLH) is the most common inherited rickets.
- XLH involves renal phosphate wasting and impaired bone mineralization.
- Inactivating mutations in the PHEX gene are linked to XLH.
Observation:
- A 54-year-old male patient presented with typical XLH features.
- Mutational analysis revealed a novel 1-bp deletion (177delC) in exon 2 of the PHEX gene.
- This deletion leads to a premature stop codon (C59X), truncating the PHEX protein.
Findings:
- Elevated fibroblast growth factor 23 (FGF23) and parathyroid hormone (PTH) levels were observed.
- Increased axial bone mineral density score was measured in the patient.
- The novel PHEX mutation (177delC) is a potential cause of XLH in this patient.
Implications:
- This case expands the spectrum of known PHEX mutations causing XLH.
- Understanding PHEX gene mutations aids in deciphering XLH pathogenetic pathways.
- Further research into PHEX function can inform XLH treatment strategies.
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