CYP27A1

Chr 2

cytochrome P450 family 27 subfamily A member 1

Also known as: CP27, CTX, CYP27

This gene encodes a member of the cytochrome P450 superfamily of enzymes. The cytochrome P450 proteins are monooxygenases which catalyze many reactions involved in drug metabolism and synthesis of cholesterol, steroids and other lipids. This mitochondrial protein oxidizes cholesterol intermediates as part of the bile synthesis pathway. Since the conversion of cholesterol to bile acids is the major route for removing cholesterol from the body, this protein is important for overall cholesterol homeostasis. Mutations in this gene cause cerebrotendinous xanthomatosis, a rare autosomal recessive lipid storage disease. [provided by RefSeq, Jul 2008]

GeneReviewsResearchGenerating clinical summary…

Primary Disease Associations & Inheritance

UniProtCerebrotendinous xanthomatosis

Clinical highlights

Gene-disease validity (ClinGen)
cerebrotendinous xanthomatosis · 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.
3
Active trials
170
Pubs (1 yr)
P/LP submissions
P/LP missense
1.38
LOEUF
LOF
Mechanism· G2P
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GeneReview available — CYP27A1
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

Tolerant — LoF & missense variants common in population
LoF Constraint?
1.38LOEUF
pLI 0.000
Z-score -0.02
OE 1.00 (0.741.38)
Tolerant

Highly tolerant — LoF variants common in population

Missense Constraint?
-0.31Z-score
OE missense 1.05 (0.961.15)
319 obs / 303.8 exp
Tolerant

Tolerant to missense variation

Observed / Expected Ratios?
LoF OE?1.00 (0.741.38)
00.351.4
Missense OE?1.05 (0.961.15)
00.61.4
Synonymous OE?0.97
01.21.6
LoF obs/exp: 28 / 27.9Missense obs/exp: 319 / 303.8Syn Z: 0.29

ClinVar Variant Classifications

0 submitted variants in ClinVar

Protein Context — Lollipop Plot

CYP27A1 · protein map & ClinVar variants

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