Is PIGN p.Ser719Pro (c.2155T>C) pathogenic?

PIGN p.Ser719Pro (c.2155T>C) is classified Uncertain significance in PIGN (ClinVar, Single submitter, 1 submitter; last evaluated 2021-08-26). AlphaMissense: likely benign (0.0987); Very rare (popmax 0.00668%, afr); Associated with multiple congenital anomalies-hypotonia-seizures syndrome 1.

What condition is associated with PIGN p.Ser719Pro (c.2155T>C)?

PIGN p.Ser719Pro (c.2155T>C) is associated with multiple congenital anomalies-hypotonia-seizures syndrome 1 (ClinVar).

How common is PIGN p.Ser719Pro (c.2155T>C) in the general population?

PIGN p.Ser719Pro (c.2155T>C) is very rare (popmax 0.00668%, afr) (gnomAD).

What do computational predictors say about PIGN p.Ser719Pro (c.2155T>C)?

AlphaMissense predicts likely benign (score 0.0987) — an in-silico prediction, not a clinical call.

PIGN p.Ser719Pro

c.2155T>C · rs781515326 · VCV954080

Uncertain significance Single submitter

Classification

Uncertain significance

ClinVar

Review

Single submitter ★☆☆☆

ClinVar · 1 submitter

AlphaMissense

likely benign

0.0987 · ACMG-weighted

gnomAD v4.1

Rare

very rare (popmax 0.00668%, afr)

Missense predictors

1/3 damaging

AlphaMissense, REVEL, SaProt

Conditions

multiple congenital anomalies-hypotonia-seizures syndrome 1

Computational evidence

Protein change
AlphaMissense	0.0987	likely benign
REVEL	0.083	moderately benign-leaning
SaProt	LLR -12.35	damaging
⇒ SaProt calls this damaging; AlphaMissense and REVEL do not.
Splicing
SpliceAI	—	not assessed · no allele here is in the release
Constraint at this position
Conservation	phyloP 2.3	GERP -1.5, phastCons 1
Regional constraint	o/e 1.01	unconstrained · MANE · 109 kb · p 0.83 · regional, not allelic
Overall
CADD	17.53	PHRED · no single calibrated threshold — expert panels disagree

AlphaMissense carries the ACMG weight for missense; REVEL and SaProt are independent agreement signals.

Population frequency

gnomAD v4.1 · exomes + genomes

Grpmax group 0.00668% African / African-American · 5/74,884 alleles

Filtering AF 0.00255% ClinGen BA1/BS1 input FAF95, joint · FAF99 0.00162%

Overall 0.000435% 7/1,610,780 alleles · very rare exomes 5/1,458,556 · genomes 2/152,224 · joint denominator

Ancestry group	Frequency	1 in
African / African-Americangrpmax	0.00668%	14,977
Remaining individualsnot grpmax-eligible	0.0016%	62,336
South Asian	0.0011%	91,006

Rarity supports pathogenicity (ACMG PM2); frequency above a disease-specific BA1/BS1 threshold argues against it. A variant frequent in one ancestry group can be near-absent in others, so a single global figure can mislead.

Variant & gene context

Gene: PIGN
Protein: p.Ser719Pro
Coding: c.2155T>C
MANE Select: NM_176787
dbSNP: rs781515326
Type: single nucleotide variant
Location: chr18:62095873 (GRCh38)
Gene constraint: LOEUF 1.46 · pLI <0.01 · ClinGen HI gene assoc. with recessive phenotype (gnomAD)
Structure: AlphaFold pLDDT 88.33

Full PIGN gene report on Sugi Atlas → Gene function, pathways, protein structure, interactions & more

Disease context

multiple congenital anomalies-hypotonia-seizures syndrome 1 — disease report on Sugi Atlas → Associated genes, phenotypes, clinical trials & treatments

Similar variants

PIGN c.1251+1G>A Pathogenic/Likely pathogenic ★★ same condition
PIGN c.1252-2A>G Pathogenic/Likely pathogenic ★★ same condition
PIGN c.1434+5G>A Pathogenic/Likely pathogenic ★★ same condition
PIGN c.1574+1G>A Likely pathogenic ★★ same condition
PIGN c.1674+1G>A Likely pathogenic ★★ same condition
PIGN c.1674+1G>C Pathogenic ★★ same condition
PIGN c.1675-1G>T Pathogenic/Likely pathogenic ★★ same condition
PIGN c.222-1G>A Likely pathogenic ★★ same condition

Built on 18 open, versioned datasets — ClinVar, gnomAD, AlphaMissense, REVEL, ClinGen & more — plus Sugi Variant's own cross-source analysis. Source data 2026-01–2026-10, ClinVar 2026-10. Full sources & versions →

Cite Sugi Variant

Gür T. Sugi Variant: A Deterministic Per-Variant Germline Reference from a Knowledge Graph for Humans and AI Agents. 2026. doi:10.5281/zenodo.21509445. This variant: https://sugi.bio/variant/pign-p-ser719pro (accessed [today's date]).

Preprint & method: sugi.bio/variant/method Machine-readable: this page as Markdown