HSD3B7

Chr 16

hydroxy-delta-5-steroid dehydrogenase, 3 beta- and steroid delta-isomerase 7

Also known as: CBAS1, PFIC4, SDR11E3

NCBI Gene: 80270ENSG00000099377UniProt: Q9H2F3

This gene encodes an enzyme which is involved in the initial stages of the synthesis of bile acids from cholesterol and a member of the short-chain dehydrogenase/reductase superfamily. The encoded protein is a membrane-associated endoplasmic reticulum protein which is active against 7-alpha hydrosylated sterol substrates. Mutations in this gene are associated with a congenital bile acid synthesis defect which leads to neonatal cholestasis, a form of progressive liver disease. Multiple transcript variants encoding different isoforms have been found for this gene. [provided by RefSeq, Dec 2008]

GeneReviewsResearchGenerating clinical summary…

Primary Disease Associations & Inheritance

UniProtCongenital bile acid synthesis defect 1

Clinical highlights

Gene-disease validity (ClinGen)
congenital bile acid synthesis defect 1 · ARDefinitivesufficient evidence for diagnostic panels
Interpreting a novel variant
Loss of function is the curated mechanism (Gene2Phenotype), though the gene is not strongly LoF-constrained in the population — weigh truncating variants against that tolerance.Curated gene-level mechanism — a prior for triage, not a per-variant call.
0
Active trials
22
Pubs (1 yr)
—
P/LP submissions
—
P/LP missense
1.33
LOEUF
LOF
Mechanism· G2P
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GeneReview available — HSD3B7
Authoritative clinical overview · Recommended first read
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Some data sources returned errors (1)

omim: Error: OMIM fetch failed: 429

Population Genetics & Constraint

gnomAD v4 — loss-of-function & missense intolerance

gnomAD
Tolerant — LoF & missense variants common in population
LoF Constraint?
1.33LOEUF
pLI 0.000
Z-score 0.59
OE 0.84 (0.55–1.33)
Tolerant

Highly tolerant — LoF variants common in population

Missense Constraint?
0.77Z-score
OE missense 0.86 (0.77–0.96)
202 obs / 235.1 exp
Tolerant

Mild missense constraint

Observed / Expected Ratios?
LoF OE?0.84 (0.55–1.33)
0≤0.351.4
Missense OE?0.86 (0.77–0.96)
0≤0.61.4
Synonymous OE?0.86
0≤1.21.6
LoF obs/exp: 13 / 15.5Missense obs/exp: 202 / 235.1Syn Z: 1.10

ClinVar Variant Classifications

0 submitted variants in ClinVar

ClinVar

Protein Context — Lollipop Plot

HSD3B7 · protein map & ClinVar variants

Showing all ClinVar variants across the protein. Search a specific variant to highlight its position.

Clinical Trials

Active and recruiting trials from ClinicalTrials.gov

ClinicalTrials.gov

No active trials found for this gene.

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External Resources

Links to major genomics databases and tools

Franklin by Genoox
AI-powered variant curation and clinical analysis
DECIPHER
Genomic variants and phenotypes in rare disease patients