PITPNB

Chr 22

phosphatidylinositol transfer protein beta

Also known as: PI-TP-beta, PtdInsTP, VIB1B

This gene encodes a cytoplasmic protein that catalyzes the transfer of phosphatidylinositol and phosphatidylcholine between membranes. This transfer activity is required for COPI complex-mediated retrograde transport from the Golgi apparatus to the endoplasmic reticulum. Alternative splicing of this gene results in multiple transcript variants. [provided by RefSeq, Sep 2013]

52
ClinVar variants
22
Pathogenic / LP
0.98
pLI score· haploinsufficient
0
Active trials
Clinical SummaryPITPNB
Population Constraint (gnomAD)
Highly constrained gene — heterozygous loss-of-function variants are very rare in the population (pLI 0.98). One damaged copy is likely sufficient to cause disease.
📋
ClinVar Variants
22 Pathogenic / Likely Pathogenic· 15 VUS of 52 total submissions

Population Genetics & Constraint

gnomAD v4 — loss-of-function & missense intolerance

LoF intolerant — likely haploinsufficient
LoF Constraint?LOEUF (Loss-of-function Observed/Expected Upper bound Fraction) is the upper bound of the 90% CI for LoF OE — the preferred gnomAD v4 metric. Lower = more intolerant to LoF. LOEUF < 0.35 = highly constrained.
0.29LOEUF
pLI 0.981
Z-score 3.54
OE 0.06 (0.020.29)
Highly constrained

Highly LoF-intolerant (top ~10% of genes)

Missense Constraint?Missense Z-score: standard deviations fewer missense variants observed vs. expected. Z > 3.09 (p < 0.001) = gene does not tolerate missense variation. OE missense < 0.6 is also considered constrained.
2.15Z-score
OE missense 0.43 (0.340.55)
49 obs / 113.6 exp
Mild constraint

Moderately missense-constrained (top ~2.5%)

Observed / Expected Ratios?Shaded band = 90% confidence interval. Vertical tick = point estimate. Grey threshold line = gnomAD constraint cutoff for that variant class.
LoF OE?Ratio of observed to expected LoF variants. Upper CI bound (LOEUF) ≤ 0.35 = strong LoF constraint signal.0.06 (0.020.29)
00.351.4
Missense OE?Ratio of observed to expected missense variants. OE ≤ 0.6 = fewer missense variants than expected by chance.0.43 (0.340.55)
00.61.4
Synonymous OE?Control metric — synonymous variants are largely neutral and expected near OE = 1.0. Significant deviation may indicate annotation issues.0.88
01.21.6
LoF obs/exp: 1 / 16.5Missense obs/exp: 49 / 113.6Syn Z: 0.60

ClinVar Variant Classifications

52 submitted variants in ClinVar

Classification Summary

Pathogenic20
Likely Pathogenic2
VUS15
Likely Benign1
20
Pathogenic
2
Likely Pathogenic
15
VUS
1
Likely Benign

Curated Variants Distribution

Classified variants from ClinVar · 5 ACMG categories

ClassificationLoFMissense + InframeNon-codingSynonymousTotal
Pathogenic
0
0
20
0
20
Likely Pathogenic
0
0
2
0
2
VUS
0
12
3
0
15
Likely Benign
0
0
1
0
1
Benign
0
0
0
0
0
Total01226038

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

View in ClinVar →

Protein Context — Lollipop Plot

PITPNB · protein map & ClinVar variants

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

OMIM — Genotype-Phenotype Relationships

1 OMIM entry

Clinical Literature
Landmark / reviewRecent case evidence
Recent Gene-Specific Literature
Gene in title · MEDLINE · newest first
Europe PMC

No open access results found

Clinical Trials

Active and recruiting trials from ClinicalTrials.gov

No active trials found for this gene.

Search ClinicalTrials.gov →