X-linked hypophosphatemia due to a de novo novel splice-site variant in a 7-year-old girl with scaphocephaly, Chiari syndrome type I and syringomyelia

Abstract

X-linked hypophosphatemia (XLH) is a rare X-linked dominant inherited disorder caused by loss-of-function variants in the PHEX gene and characterized by renal phosphate wasting, hypophosphatemia, abnormal vitamin D metabolism, growth retardation and lower limb deformities. We describe a case of XLH-rickets in a 7-year-old girl with scaphocephaly, Chiari syndrome type I and syringomyelia, with a de novo non-canonical splice variant (c.1080-3C > G) in intron 9 of the PHEX gene, that has not been previously described.

Keywords

• X-linked hypophosphatemia
• Rickets
• Phosphate-regulating gene with homologies to endopeptidases on the X chromosome (PHEX)
• Chiari syndrome
• Craniosynostosis
• Splice-site mutation