FCER1G

Chr 1

Fc epsilon receptor Ig

Also known as: FCRG

NCBI Gene: 2207 ENSG00000158869 UniProt: P30273 OMIM: 147139

The high affinity IgE receptor is a key molecule involved in allergic reactions. It is a tetramer composed of 1 alpha, 1 beta, and 2 gamma chains. The gamma chains are also subunits of other Fc receptors. [provided by RefSeq, Jul 2008]

OMIM Research

OMIM ResearchGenerating clinical summary…

MultiplemechanismLOEUF 0.61

Clinical Summary— FCER1G

⚡

Population Constraint (gnomAD)

Moderately constrained gene (pLI 0.66) — some intolerance to loss-of-function variants.

📋

ClinVar Variants

9 VUS of 17 total submissions

Explore recent and relevant literature in Research Assistant →

Population Genetics & Constraint

gnomAD v4 — loss-of-function & missense intolerance

gnomAD

Moderate LoF intolerance

LoF Constraint?

0.61LOEUF

pLI 0.663

Z-score 2.26

OE 0.13 (0.04–0.61)

Moderately constrained

Typical tolerance to LoF variation

Missense Constraint?

-0.02Z-score

OE missense 1.01 (0.79–1.29)

45 obs / 44.6 exp

Tolerant

Tolerant to missense variation

Observed / Expected Ratios?

LoF OE?0.13 (0.04–0.61)

0≤0.351.4

Missense OE?1.01 (0.79–1.29)

0≤0.61.4

Synonymous OE?0.85

0≤1.21.6

LoF obs/exp: 1 / 7.8Missense obs/exp: 45 / 44.6Syn Z: 0.51

This gene — mechanism propensity

0.7229th %ile

GOF

0.76top 25%

LOF

0.2387th %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

17 submitted variants in ClinVar

ClinVar

Classification Summary

VUS9

VUS

Curated Variants Distribution

Classified variants from ClinVar · 5 ACMG categories

Classification	Missense + Inframe	Non-coding	Total
Pathogenic	0	0	0
Likely Pathogenic	0	0	0
VUS	8	1	9
Likely Benign	0	0	0
Benign	0	0	0
Total	8	1	9

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

View in ClinVar →

12 pathogenic / likely-pathogenic (of 22) ClinVar copy-number / structural variants overlap FCER1G — these span large chromosomal regions, not the gene specifically, and are excluded from the counts above. Explore in CNV tools →