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Gene

PHEX

phosphate regulating endopeptidase X-linked

Summary

Cytogenetic location
Xp22.11
Coordinates
Chromosome X: 22,032,325–22,251,310 (GRCh38)
Exons
22 exons across 219 kb
Protein
749 amino acids
Also known as
PEX, HPDR1, HYP1, XLH
Previous symbols
HYP, HPDR
MANE Select transcript
ENST00000379374.5NM_000444.6
Locus type
gene with protein product
  • Very high
  • Confident
  • Low
  • Very low

Reference genomeGRCh38

Positions on gene and variant pages follow this choice, in this browser.

Curated report relevant to this gene

  • Hereditary Rickets (Hypophosphatemic and Vitamin D-Dependent)

    • Hereditary hypophosphatemic rickets (including X-linked hypophosphatemia)

      Inherited disorders of phosphate handling, most often caused by PHEX variants (X-linked hypophosphatemia) and less often by FGF23, DMP1, ENPP1 or SLC34A3, that lead to low blood phosphate and rickets.

      • ClinGen rates the link definitive
      • 5 GenCC submitters rate it definitive or strong
      What knowing changes

      Treatment with oral phosphate and active vitamin D, or with the anti-FGF23 antibody burosumab, can improve bone health and growth.

How PHEX is laid out

  • Coding sequence
  • Untranslated region
  • Intron
  • Direction of transcription
  • Known disease-causing sites
  • Stretches short reads find hard
Chromosome X, with a bracket where PHEX sits. PHEX and 7 genes near it on chromosome X, from 21,641,818 to 22,641,817.Chromosome XXp22.11p22.33p22.32p22.31p22.2p22.13p22.12p22.11p21.3p21.2p21.1p11.4p11.3p11.23p11.22p11.21p11.1q11.1q11.2q12q13.1q13.2q13.3q21.1q21.2q21.31q21.32q21.33q22.1q22.2q22.3q23q24q25q26.1q26.2q26.3q27.1q27.2q27.3q2821.8 Mb22 Mb22.2 Mb22.4 Mb22.6 MbCNKSR2: 21,372,801–21,654,701, forward strandCNKSR2KLHL34: 21,654,690–21,658,330, reverse strandKLHL34SMPX: 21,704,788–21,758,254, reverse strandSMPXMBTPS2: 21,839,600–21,935,555, forward strandMBTPS2YY2: 21,855,987–21,858,740, forward strandYY2SMS: 21,940,557–21,994,837, forward strandSMSPHEX: 22,032,325–22,251,310, forward strandPHEXCBLL2: 22,272,913–22,274,461, forward strandCBLL2Diagram of PHEX: 22 exons on the forward strand of chromosome XExon 1: 7 known disease-causing sitesExon 2: 5 known disease-causing sitesExon 3: 13 known disease-causing sitesExon 4: 8 known disease-causing sitesExon 5: 18 known disease-causing sitesExon 6: 8 known disease-causing sitesExon 7: 6 known disease-causing sitesExon 8: 4 known disease-causing sitesExon 9: 12 known disease-causing sitesExon 10: 5 known disease-causing sitesExon 11: 11 known disease-causing sitesExon 12: 19 known disease-causing sitesExon 13: 6 known disease-causing sitesExon 14: 11 known disease-causing sitesExon 15: 4 known disease-causing sitesExon 16: 4 known disease-causing sitesExon 17: 13 known disease-causing sitesExon 18: 16 known disease-causing sitesExon 19: 11 known disease-causing sitesExon 20: 14 known disease-causing sitesExon 21: 11 known disease-causing sitesExon 22: 16 known disease-causing sitesExon 1: 22,032,325–22,033,123, 799 basesExon 2: 22,038,469–22,038,537, 69 basesExon 3: 22,047,050–22,047,211, 162 basesExon 4: 22,076,388–22,076,474, 87 basesExon 5: 22,077,476–22,077,702, 227 basesExon 6: 22,090,429–22,090,497, 69 basesExon 7: 22,093,983–22,094,099, 117 basesExon 8: 22,096,955–22,097,038, 84 basesExon 9: 22,099,006–22,099,151, 146 basesExon 10: 22,111,467–22,111,560, 94 basesExon 11: 22,114,458–22,114,586, 129 basesExon 12: 22,133,523–22,133,624, 102 basesExon 13: 22,168,312–22,168,389, 78 basesExon 14: 22,178,273–22,178,376, 104 basesExon 15: 22,190,444–22,190,502, 59 basesExon 16: 22,212,904–22,212,958, 55 basesExon 17: 22,219,036–22,219,103, 68 basesExon 18: 22,221,613–22,221,743, 131 basesExon 19: 22,226,443–22,226,508, 66 basesExon 20: 22,227,507–22,227,611, 105 basesExon 21: 22,245,333–22,245,409, 77 basesExon 22: 22,247,851–22,251,310, 3,460 bases12468101214161820225′3′

Exons of the gene's MANE Select transcript (release v1.5), from NCBI and EMBL-EBI, on the GRCh38 reference genome.

Chromosome bands from UCSC's GRCh38 ideogram (2022-10-29).

Nearby genes from Ensembl release 116, on GRCh38.

Exons make up 6.3 kb of the gene's 219 kb; 2,250 of those bases code for the protein.

How a genome test reads PHEX

293

positions in PHEX where ClinVar classes a change as pathogenic or likely pathogenic

None of them falls in a region short reads find hard.

A whole genome covers all 219 kb of PHEX, introns included, not only the 6.3 kb of exons.

Where this comes from

  • HGNC: the gene's symbol, name, other symbols and location.
  • MANE Select v1.5, from NCBI and EMBL-EBI: the transcript, its exons and coding sequence.
  • GenCC and ClinGen, released 2026-10-16: which conditions the gene is linked to, and how strongly.
  • The ACMG secondary findings list, SF v3.2.
  • ClinVar and the GIAB stratifications: known disease-causing sites, and the regions short reads find hard.
  • The Human Phenotype Ontology, release 2026-09-01: the traits linked to the gene. Find out more at hpo.jax.org.
  • Data release 2026.10.16-c6eea6bf.

Cite this page

APA

Dante Labs. (n.d.). PHEX gene: phosphate regulating endopeptidase X-linked. Retrieved 17 October 2026, from https://dantelabs.com/genes/phex

Vancouver

Dante Labs. PHEX gene: phosphate regulating endopeptidase X-linked [Internet]. [cited 17 October 2026]. Available from: https://dantelabs.com/genes/phex

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