GUCA1C

Chr 3

guanylate cyclase activator 1C

Also known as: GCAP3

The protein functions as a calcium-sensitive regulator of guanylyl cyclases in rod photoreceptors, stimulating these enzymes at low calcium concentrations and inhibiting them at high calcium concentrations to enable recovery of the dark state following light exposure. Mutations cause autosomal recessive cone-rod dystrophy, a retinal degeneration affecting both cone and rod photoreceptors. This gene shows low constraint against loss-of-function variants, consistent with recessive inheritance where both copies must be affected to cause disease.

OMIMResearchSummary from RefSeq, UniProt
MultiplemechanismLOEUF 1.88
Clinical SummaryGUCA1C
Population Constraint (gnomAD)
Low constraint (pLI 0.00) — loss-of-function variants are relatively tolerated in the population.
📋
ClinVar Variants
16 unique Pathogenic / Likely Pathogenic· 38 VUS of 68 total submissions

Population Genetics & Constraint

gnomAD v4 — loss-of-function & missense intolerance

Tolerant — LoF & missense variants common in population
LoF Constraint
1.88LOEUF
pLI 0.000
Z-score -0.67
OE 1.27 (0.751.88)
Tolerant

Highly tolerant — LoF variants common in population

Missense Constraint
-0.32Z-score
OE missense 1.09 (0.931.27)
116 obs / 106.8 exp
Tolerant

Tolerant to missense variation

Observed / Expected Ratios
LoF OE1.27 (0.751.88)
00.351.4
Missense OE1.09 (0.931.27)
00.61.4
Synonymous OE0.84
01.21.6
LoF obs/exp: 9 / 7.1Missense obs/exp: 116 / 106.8Syn Z: 0.76
DN
0.77top 25%
GOF
0.81top 10%
LOF
0.2288th %ile

This gene has evidence for multiple mechanisms of pathogenicity (gain-of-function and dominant-negative). Both the Badonyi & Marsh prediction and the broader genomic evidence point to gain-of-function as the predominant mechanism. Different variants in this gene may act through different mechanisms — interpret in context of the specific variant.

GOFprediction above median
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

68 submitted variants in ClinVar

Classification Summary

Pathogenic16
VUS38
Likely Benign6
16
Pathogenic
38
VUS
6
Likely Benign

Curated Variants Distribution

Classified variants from ClinVar · 5 ACMG categories

ClassificationLoFMissense + InframeNon-codingSynonymousTotal
Pathogenic
0
0
16
0
16
Likely Pathogenic
0
0
0
0
0
VUS
0
32
6
0
38
Likely Benign
0
3
3
0
6
Benign
0
0
0
0
0
Total03525060

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

View in ClinVar →

Protein Context — Lollipop Plot

GUCA1C · 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.

Search ClinicalTrials.gov →
Clinical Literature
Open Research Assistant →
Key Publications
Landmark & review papers · by relevance
PubMed
Top 2 results · since 2015Search PubMed ↗
Recent Gene-Specific Literature
Gene in title · MEDLINE · newest first
Europe PMC
An Assessment of GUCA1C Variants in Primary Congenital Glaucoma.
Souzeau E et al.·Genes (Basel)
2021Open Access