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Gene

CTSK

cathepsin K

Summary

Cytogenetic location
1q21.3
Coordinates
Chromosome 1: 150,796,208–150,808,260 (GRCh38)
Exons
8 exons across 12.1 kb
Protein
329 amino acids
Also known as
PKND
Previous symbols
CTSO2, CTSO, PYCD
MANE Select transcript
ENST00000271651.8NM_000396.4
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 reports relevant to this gene

  • Osteopetrosis

    • Osteopetrosis, also known as marble bone disease, is a descriptive term that refers to a group of rare, heritable disorders of the skeleton characterized by increased bone density on radiographs.

      • ClinGen rates the link definitive
      • 7 GenCC submitters rate it definitive or strong

Broader groupings

  • Lysosomal Storage Disease

    • Lysosomal storage disease (other and unspecified types)

      One of 59 genes linked to it

      Covers lysosomal storage diseases without a dedicated report, such as Farber disease and other ASAH1-related disorders, prosaposin (PSAP) deficiencies, multiple sulfatase deficiency, mucopolysaccharidosis types IX and X, and Dorfman-Chanarin disease; inheritance varies by subtype, most often autosomal recessive.

      • ClinGen rates the link definitive
      • 7 GenCC submitters rate it definitive or strong

How CTSK is laid out

  • Coding sequence
  • Untranslated region
  • Intron
  • Direction of transcription
  • Known disease-causing sites
  • Stretches short reads find hard
Chromosome 1, with a bracket where CTSK sits. CTSK and 33 genes near it on chromosome 1, from 150,302,234 to 151,302,233.Chromosome 11q21.3p36.33p36.32p36.31p36.23p36.22p36.21p36.13p36.12p36.11p35.3p35.2p35.1p34.3p34.2p34.1p33p32.3p32.2p32.1p31.3p31.2p31.1p22.3p22.2p22.1p21.3p21.2p21.1p13.3p13.2p13.1p12p11.2p11.1q11q12q21.1q21.2q21.3q22q23.1q23.2q23.3q24.1q24.2q24.3q25.1q25.2q25.3q31.1q31.2q31.3q32.1q32.2q32.3q41q42.11q42.12q42.13q42.2q42.3q43q44150.4 Mb150.6 Mb150.8 Mb151 Mb151.2 MbMRPS21: 150,293,848–150,309,828, forward strandMRPS21PRPF3: 150,321,476–150,353,341, forward strandPRPF3RPRD2: 150,363,091–150,476,999, forward strandRPRD2TARS2: 150,487,325–150,507,614, forward strandTARS2ECM1: 150,507,989–150,515,000, forward strandECM1ADAMTSL4: 150,549,369–150,560,937, forward strandADAMTSL4MCL1: 150,560,895–150,579,738, reverse strandMCL1ENSA: 150,599,671–150,629,633, reverse strandENSAGOLPH3L: 150,638,727–150,697,222, reverse strandGOLPH3LHORMAD1: 150,698,059–150,720,895, reverse strandHORMAD1CTSS: 150,730,079–150,765,957, reverse strandCTSSCTSK: 150,796,208–150,808,260, reverse strandCTSKARNT: 150,808,617–150,876,771, reverse strandARNTCTXND2: 150,887,136–150,913,292, forward strandCTXND2SETDB1: 150,926,263–150,964,748, forward strandSETDB1CERS2: 150,959,099–150,977,396, reverse strandCERS2ANXA9: 150,981,321–150,996,077, forward strandANXA9MINDY1: 150,995,125–151,008,376, reverse strandMINDY1PRUNE1: 151,008,408–151,035,714, forward strandPRUNE1BNIPL: 151,036,321–151,047,720, forward strandBNIPLC1orf56: 151,047,746–151,051,986, forward strandC1orf56CDC42SE1: 151,050,242–151,070,325, reverse strandMLLT11: 151,054,177–151,069,544, forward strandGABPB2: 151,070,514–151,130,109, forward strandSEMA6C: 151,131,685–151,147,813, reverse strandSEMA6CTIPE2: 151,156,621–151,160,255, forward strandTIPE2SCNM1: 151,156,664–151,179,006, forward strandSCNM1LYSMD1: 151,159,748–151,165,948, reverse strandLYSMD1TMOD4: 151,169,984–151,176,284, reverse strandVPS72: 151,176,304–151,195,321, reverse strandPIP5K1A: 151,197,949–151,249,538, forward strandPIP5K1APSMD4: 151,254,709–151,279,502, forward strandPSMD4ZNF687: 151,281,502–151,292,180, forward strandZNF687PI4KB: 151,291,792–151,328,394, reverse strandPI4KBDiagram of CTSK: 8 exons on the reverse strand of chromosome 1Exon 8: 9 known disease-causing sitesExon 7: 7 known disease-causing sitesExon 6: 16 known disease-causing sitesExon 5: 21 known disease-causing sitesExon 4: 12 known disease-causing sitesExon 3: 14 known disease-causing sitesExon 2: 12 known disease-causing sitesExon 8: 150,796,208–150,796,898, 691 basesExon 7: 150,799,168–150,799,273, 106 basesExon 6: 150,799,544–150,799,709, 166 basesExon 5: 150,804,021–150,804,239, 219 basesExon 4: 150,805,861–150,806,016, 156 basesExon 3: 150,806,102–150,806,224, 123 basesExon 2: 150,806,686–150,806,806, 121 basesExon 1: 150,808,214–150,808,260, 47 bases876543215′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 1.6 kb of the gene's 12.1 kb; 990 of those bases code for the protein.

How a genome test reads CTSK

102

positions in CTSK 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 12.1 kb of CTSK, introns included, not only the 1.6 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.). CTSK gene: cathepsin K. Retrieved 16 October 2026, from https://dantelabs.com/genes/ctsk

Vancouver

Dante Labs. CTSK gene: cathepsin K [Internet]. [cited 16 October 2026]. Available from: https://dantelabs.com/genes/ctsk

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