TRAPPC1

Chr 17

trafficking protein particle complex subunit 1

TRAPPC1 encodes a component of the transport protein particle (TRAPP) complex that facilitates vesicular transport from the endoplasmic reticulum to the Golgi apparatus. Mutations cause autosomal recessive limb-girdle muscular dystrophy type 18 (LGMDR18), characterized by progressive proximal muscle weakness typically beginning in childhood or adolescence. The gene shows low constraint against loss-of-function variants, consistent with its recessive inheritance pattern.

OMIMResearchSummary from UniProt
DNmechanismLOEUF 0.90
Clinical SummaryTRAPPC1
Population Constraint (gnomAD)
Constrained for loss-of-function variants (OE-LoF 0.35) despite low pLI — interpret in context.
Some data sources returned errors (1)

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Population Genetics & Constraint

gnomAD v4 — loss-of-function & missense intolerance

Tolerant — LoF & missense variants common in population
LoF Constraint
0.90LOEUF
pLI 0.087
Z-score 1.77
OE 0.35 (0.160.90)
Tolerant

Typical tolerance to LoF variation

Missense Constraint
1.28Z-score
OE missense 0.62 (0.500.77)
55 obs / 89.0 exp
Tolerant

Mild missense constraint

Observed / Expected Ratios
LoF OE0.35 (0.160.90)
00.351.4
Missense OE0.62 (0.500.77)
00.61.4
Synonymous OE1.17
01.21.6
LoF obs/exp: 3 / 8.6Missense obs/exp: 55 / 89.0Syn Z: -0.82
DN
0.6936th %ile
GOF
0.4776th %ile
LOF
0.3164th %ile

The highest-scoring mechanism for this gene is dominant-negative.

DNprediction above median

Note: In-silico variant effect predictors (SIFT, PolyPhen, REVEL, CADD) may underestimate pathogenicity of missense variants in genes with GOF or DN mechanisms. Consider functional evidence and clinical context.

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

ClinVar Variant Classifications

0 submitted variants in ClinVar

Protein Context — Lollipop Plot

TRAPPC1 · 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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