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Updated: Dec 9, 2025
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Targeted Next-generation Sequencing and Bioinformatics Pipeline to Evaluate Genetic Determinants of Constitutional Disease
Published on: April 4, 2018
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X-linked hypophosphatemic rickets: a new mutation.
Patrícia Maio1, Lia Mano2, Sara Rocha3
1Hospital do Espírito Santo de Évora, Évora, Portugal.
Jornal Brasileiro De Nefrologia
|September 8, 2020
Summary
A new PHEX gene mutation, c.767_768del, caused phosphopenic rickets in a child. Identifying novel mutations aids in understanding genotype-phenotype correlations for better patient outcomes.
Area of Science:
- Genetics
- Pediatrics
- Endocrinology
Background:
- Phosphopenic rickets, a condition characterized by low phosphate levels leading to bone deformities, is often caused by mutations in the phosphate regulating endopeptidase homolog X-linked (PHEX) gene.
- Over 500 PHEX gene mutations have been identified, contributing to various forms of hypophosphatemic rickets.
Observation:
- A 4-year-old girl presented with failure to thrive and bowed legs, despite no significant family history of genetic disorders.
- Laboratory results revealed hypophosphatemia, elevated alkaline phosphatase, normal calcium and vitamin D levels, and mildly elevated parathyroid hormone.
- Radiological imaging showed deformities in the radius and femur, consistent with rickets.
Findings:
- Genetic analysis identified a novel heterozygous likely pathogenic variant in the PHEX gene: c.767_768del (p.Thr256Serfs*7).
- This specific PHEX gene variant had not been previously reported in scientific literature or genetic databases.
Implications:
- The discovery of new PHEX gene mutations is crucial for improving the diagnosis and management of phosphopenic rickets.
- Establishing genotype-phenotype correlations through genetic analysis can lead to more personalized and effective patient care strategies.
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