PIBF1

Chr 13AR

progesterone immunomodulatory binding factor 1

Also known as: C13orf24, CEP90, JBTS33, PIBF

This protein is induced by progesterone and plays a role in ciliogenesis. Mutations cause Joubert syndrome 33, a ciliopathy presenting in infancy with cerebellar vermis hypoplasia, developmental delay, hypotonia, and characteristic breathing abnormalities. The condition follows autosomal recessive inheritance.

GeneReviewsOMIMResearchSummary from RefSeq, OMIM, UniProt
LOFmechanismARLOEUF 0.721 OMIM phenotype
Clinical SummaryPIBF1
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Gene-Disease Validity (ClinGen)
ciliopathy · ARModerate

Moderate evidence — consider for supplementary testing

Population Constraint (gnomAD)
Low constraint (pLI 0.00) — loss-of-function variants are relatively tolerated in the population.
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ClinVar Variants
86 unique Pathogenic / Likely Pathogenic· 150 VUS of 339 total submissions
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GeneReview available — PIBF1
Authoritative clinical overview · Recommended first read
Open GeneReview ↗

Population Genetics & Constraint

gnomAD v4 — loss-of-function & missense intolerance

Tolerant — LoF & missense variants common in population
LoF Constraint
0.72LOEUF
pLI 0.000
Z-score 3.16
OE 0.52 (0.380.72)
Tolerant

Typical tolerance to LoF variation

Missense Constraint
-0.46Z-score
OE missense 1.07 (0.981.16)
392 obs / 367.4 exp
Tolerant

Tolerant to missense variation

Observed / Expected Ratios
LoF OE0.52 (0.380.72)
00.351.4
Missense OE1.07 (0.981.16)
00.61.4
Synonymous OE1.09
01.21.6
LoF obs/exp: 26 / 50.2Missense obs/exp: 392 / 367.4Syn Z: -0.81
Curated Mechanism (G2P)Gene2Phenotype (DDG2P) ↗
definitivePIBF1-related Joubert syndromeLOFAR

Predictions shown for reference only — model trained on dominant genes, not applicable to AR conditions.

DN
0.79top 25%
GOF
0.6834th %ile
LOF
0.2777th %ile

The Badonyi & Marsh prediction model was trained exclusively on dominant disease genes. Predictions are not reliable for genes with autosomal recessive inheritance and are shown at reduced opacity for reference only.

Predictions from Badonyi M, Marsh JA. PLoS ONE. 2024;19(8):e0307312.

ClinVar Variant Classifications

339 submitted variants in ClinVar

Classification Summary

Pathogenic76
Likely Pathogenic10
VUS150
Likely Benign53
Benign15
Conflicting8
76
Pathogenic
10
Likely Pathogenic
150
VUS
53
Likely Benign
15
Benign
8
Conflicting

Curated Variants Distribution

Classified variants from ClinVar · 5 ACMG categories

ClassificationLoFMissense + InframeNon-codingSynonymousTotal
Pathogenic
5
2
69
0
76
Likely Pathogenic
8
2
0
0
10
VUS
6
123
19
2
150
Likely Benign
0
12
12
29
53
Benign
0
4
8
3
15
Conflicting
8
Total1914310834312

LoF = frameshift, stop gained/lost, canonical splice · Counts from ClinVar esearch · Updated hourly

View in ClinVar →

Protein Context — Lollipop Plot

PIBF1 · protein map & ClinVar variants

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

3D Protein StructureAlphaFold

Clinical Trials

Active and recruiting trials from ClinicalTrials.gov

No active trials found for this gene.

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Clinical Literature
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