title: A novel de novo mutation within PHEX gene in a young girl with hypophosphatemic rickets and review of literature.
abstract: X-linked hypophosphatemia (XLH) is the most common form of familial hypophosphatemic rickets and it is caused by loss-of-function mutations in the PHEX gene. Recently, a wide variety of PHEX gene defects in XLH have been revealed; these include missense mutations, nonsense mutations, splice site mutations, insertions, and deletions. Recently, we encountered a 2-year-9-month-old female with sporadic hypophosphatemic rickets. She underwent osteotomy, dental abscess was evident, and there was severe bowing of the legs. A low serum phosphorus level in combination with elevated serum alkaline phosphatase activity and normal serum calcium is suggestive of hypophosphatemic rickets. PHEX gene analysis revealed a splice acceptor site mutation, c.934-1G>T (IVS8(-1)G>T), at the intron8 and exon9 junction. To the best of our knowledge, this mutation is novel and has not been reported. The results of this study expand and improve our understanding of the clinical and molecular characteristics and the global pool of patients with sporadic hypophosphatemic rickets.
authors.affiliation: Department of Pediatrics, Pusan National University Children's Hospital, Pusan National University School of Medicine, Yangsan, Korea.
authors.forename: Chong Kun
authors.initials: CK
authors.lastname: Cheon
authors.affiliation: Department of Pediatrics, Pusan National University Children's Hospital, Pusan National University School of Medicine, Yangsan, Korea.
authors.forename: Hoon Sang
authors.initials: HS
authors.lastname: Lee
authors.affiliation: Department of Pediatrics, Pusan National University Children's Hospital, Pusan National University School of Medicine, Yangsan, Korea.
authors.forename: Su Yung
authors.initials: SY
authors.lastname: Kim
authors.affiliation: Department of Pediatrics, Pusan National University Hospital, Pusan National University School of Medicine, Busan, Korea.
authors.forename: Min Jung
authors.initials: MJ
authors.lastname: Kwak
authors.affiliation: Medical Genetics Clinic and Laboratory, Asan Medical Center Children's Hospital, Seoul, Korea.
authors.forename: Gu-Hwan
authors.initials: GH
authors.lastname: Kim
authors.affiliation: Medical Genetics Clinic and Laboratory, Asan Medical Center Children's Hospital, Seoul, Korea.
authors.forename: Han-Wook
authors.initials: HW
authors.lastname: Yoo
keywords: Hunam PHEX protein; Hypophospatemic rickets; Mutation