PIBF1

Chr 13

progesterone immunomodulatory binding factor 1

Also known as: C13orf24, CEP90, JBTS33, PIBF

NCBI Gene: 10464 ENSG00000083535 UniProt: Q8WXW3

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.

GeneReviews ResearchSummary from RefSeq, OMIM, UniProt

This gene encodes a protein that is induced by the steroid hormone progesterone and plays a role in the maintenance of pregnancy. The encoded protein regulates multiple facets of the immune system to promote normal pregnancy including cytokine synthesis, natural killer (NK) cell activity, and arachidonic acid metabolism. Low serum levels of this protein have been associated with spontaneous pre-term labor in humans. This protein may promote the proliferation, migration and invasion of glioma. [provided by RefSeq, Mar 2017]

GeneReviews ResearchGenerating clinical summary…

Primary Disease Associations & Inheritance

UniProtJoubert syndrome 33

Clinical highlights

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.

Active trials

Pubs (1 yr)

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P/LP submissions

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P/LP missense

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LOEUF

LOF

Mechanism· G2P

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GeneReview available — PIBF1

Authoritative clinical overview · Recommended first read

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Some data sources returned errors (2)

gnomad: Error: gnomAD API error: 400

omim: Error: OMIM fetch failed: 429

Population Genetics & Constraint

gnomAD

Constraint data not available from gnomAD.

Background carrier burden — how many people carry a rare variant somewhere in PIBF1?

gnomAD v4 · ~731k individuals · PASS only

Rare means allele frequency under

Rare missense

1 in 72

990 rare PASS variants

Rare truncating (LoF)

1 in 650

216 rare PASS variants

Rare synonymous (reference)

1 in 130

327 rare PASS variants

Truncating variants are far rarer here than missense — that gap, in human units, is what constraint means for PIBF1. A background rate for each class, not the frequency of any particular variant; thin-coverage exons undercount.

By genetic ancestry · 9 gnomAD groups · rare = under 0.1% in that group

Group	People	Missense	Truncating
European (non-Finnish)	~556k	1 in 120	1 in 680
South Asian	~43k	1 in 57	1 in 520
Remaining (unassigned)	~30k	1 in 74	1 in 890
European (Finnish)	~27k	1 in 370	1 in 2,400
Admixed American	~22k	1 in 42	1 in 610
African / African American	~21k	1 in 45	1 in 350
East Asian	~20k	1 in 54	1 in 1,100
Ashkenazi Jewish	~13k	1 in 110	1 in 1,200
Middle Eastern	~2,884	1 in 82	≈ 1 in 1,200

Each group is summed over the variants that are rare in that group. Grey ≈ figures rest on fewer than five expected carriers — too few to distinguish groups. Differences mostly reflect how many people were sampled and how much variation each ancestry carries, not disease risk.

Exome coverage (gnomAD): 7 of 17 coding exons well covered in gnomAD exomes; exons 3, 4, 7, 9, 10 and 5 more marginal. Genomes: all 17.? see exons ↓