PIGN

Chr 18

phosphatidylinositol glycan anchor biosynthesis class N

Also known as: GPI-ETI, MCAHS, MCAHS1, MCD4, MDC4, PIG-N

NCBI Gene: 23556ENSG00000197563UniProt: O95427

This gene encodes a protein that is involved in glycosylphosphatidylinositol (GPI)-anchor biosynthesis. The GPI-anchor is a glycolipid found on many blood cells and serves to anchor proteins to the cell surface. This protein is expressed in the endoplasmic reticulum and transfers phosphoethanolamine (EtNP) to the first mannose of the GPI anchor. Two alternatively spliced variants, which encode an identical isoform, have been reported. [provided by RefSeq, Jul 2008]

GeneReviewsResearchGenerating clinical summary…

Primary Disease Associations & Inheritance

UniProtMultiple congenital anomalies-hypotonia-seizures syndrome 1

Clinical highlights

Gene-disease validity (ClinGen)
multiple congenital anomalies-hypotonia-seizures syndrome 1 · ARDefinitivesufficient evidence for diagnostic panels
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.
0
Active trials
26
Pubs (1 yr)
—
P/LP submissions
—
P/LP missense
1.02
LOEUF
LOF
Mechanism· G2P
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GeneReview available — PIGN
Authoritative clinical overview · Recommended first read
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Some data sources returned errors (1)

omim: Error: OMIM fetch failed: 429

Population Genetics & Constraint

gnomAD v4 — loss-of-function & missense intolerance

gnomAD
Tolerant — LoF & missense variants common in population
LoF Constraint?
1.02LOEUF
pLI 0.000
Z-score 1.41
OE 0.78 (0.60–1.02)
Tolerant

Highly tolerant — LoF variants common in population

Missense Constraint?
0.42Z-score
OE missense 0.94 (0.87–1.02)
412 obs / 436.4 exp
Tolerant

Mild missense constraint

Observed / Expected Ratios?
LoF OE?0.78 (0.60–1.02)
0≤0.351.4
Missense OE?0.94 (0.87–1.02)
0≤0.61.4
Synonymous OE?1.04
0≤1.21.6
LoF obs/exp: 38 / 48.6Missense obs/exp: 412 / 436.4Syn Z: -0.35

ClinVar Variant Classifications

0 submitted variants in ClinVar

ClinVar

Protein Context — Lollipop Plot

PIGN · protein map & ClinVar variants

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

Clinical Trials

Active and recruiting trials from ClinicalTrials.gov

ClinicalTrials.gov

No active trials found for this gene.

Search ClinicalTrials.gov →

External Resources

Links to major genomics databases and tools

Franklin by Genoox
AI-powered variant curation and clinical analysis
DECIPHER
Genomic variants and phenotypes in rare disease patients