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Gene

DHCR7

7-dehydrocholesterol reductase

Summary

Cytogenetic location
11q13.4
Coordinates
Chromosome 11: 71,434,411–71,448,393 (GRCh38)
Exons
9 exons across 14 kb
Protein
475 amino acids
Inheritance
Autosomal recessive
Previous symbols
SLOS
MANE Select transcript
ENST00000355527.8NM_001360.3
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

  • Smith-Lemli-Opitz Syndrome

    • Autosomal recessive

      A disorder of cholesterol synthesis caused by changes in both copies of DHCR7, with a wide range of severity including growth problems, intellectual disability, characteristic malformations and cataracts.

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

      Cholesterol supplementation is commonly used, and carrier status is relevant to family planning.

Inheritance

Autosomal recessive
It takes a changed copy from each parent. With one, you are a carrier and usually unaffected; when both parents are carriers, each child has a one-in-four chance of inheriting two.

How DHCR7 is laid out

  • Coding sequence
  • Untranslated region
  • Intron
  • Direction of transcription
  • Known disease-causing sites
  • Stretches short reads find hard
Chromosome 11, with a bracket where DHCR7 sits. DHCR7 and 12 genes near it on chromosome 11, from 70,941,402 to 71,941,401.Chromosome 1111q13.4p15.5p15.4p15.3p15.2p15.1p14.3p14.2p14.1p13p12p11.2p11.12p11.11q11q12.1q12.2q12.3q13.1q13.2q13.3q13.4q13.5q14.1q14.2q14.3q21q22.1q22.2q22.3q23.1q23.2q23.3q24.1q24.2q24.3q2571 Mb71.2 Mb71.4 Mb71.6 Mb71.8 MbSHANK2: 70,467,805–71,252,844, reverse strandSHANK2DHCR7: 71,434,411–71,448,393, reverse strandDHCR7NADSYN1: 71,453,109–71,524,107, forward strandNADSYN1KRTAP5-7: 71,527,267–71,528,669, forward strandKRTAP5-7KRTAP5-8: 71,538,025–71,539,209, forward strandKRTAP5-8KRTAP5-9: 71,548,420–71,549,608, forward strandKRTAP5-9KRTAP5-10: 71,565,563–71,566,735, forward strandKRTAP5-11: 71,581,855–71,603,353, reverse strandKRTAP5-11XNDC1N-ZNF705EP-ALG1L9P: 71,804,997–71,928,656, reverse strandXNDC1N-ZNF705EP-ALG1L9PDEFB108B: 71,833,200–71,837,710, forward strandDEFB108BXNDC1N: 71,865,504–71,928,917, reverse strandXNDC1NDEFB131B: 71,878,453–71,884,561, forward strandDEFB131BRNF121: 71,929,005–71,997,597, forward strandRNF121Diagram of DHCR7: 9 exons on the reverse strand of chromosome 11Exon 9: 78 known disease-causing sitesExon 8: 35 known disease-causing sitesExon 7: 33 known disease-causing sitesExon 6: 30 known disease-causing sitesExon 5: 13 known disease-causing sitesExon 4: 30 known disease-causing sitesExon 3: 10 known disease-causing sitesExon 9: 71,434,411–71,435,839, 1,429 basesExon 8: 71,437,812–71,437,943, 132 basesExon 7: 71,438,879–71,439,083, 205 basesExon 6: 71,441,227–71,441,440, 214 basesExon 5: 71,442,263–71,442,353, 91 basesExon 4: 71,443,993–71,444,215, 223 basesExon 3: 71,444,855–71,444,958, 104 basesExon 2: 71,447,610–71,447,734, 125 basesExon 1: 71,448,290–71,448,393, 104 bases9876543215′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 2.6 kb of the gene's 14 kb; 1,428 of those bases code for the protein.

How a genome test reads DHCR7

252

positions in DHCR7 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 14 kb of DHCR7, introns included, not only the 2.6 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.). DHCR7 gene: 7-dehydrocholesterol reductase. Retrieved 16 October 2026, from https://dantelabs.com/genes/dhcr7

Vancouver

Dante Labs. DHCR7 gene: 7-dehydrocholesterol reductase [Internet]. [cited 16 October 2026]. Available from: https://dantelabs.com/genes/dhcr7

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