Is ALG1 p.Asp291Glu (c.873C>G) pathogenic?

ALG1 p.Asp291Glu (c.873C>G) is classified Uncertain significance in ALG1 (ClinVar, Single submitter, 1 submitter; last evaluated 2022-07-27). AlphaMissense: likely pathogenic (0.865); Very rare (popmax 8.48e-05%, nfe); Associated with ALG1-congenital disorder of glycosylation.

What condition is associated with ALG1 p.Asp291Glu (c.873C>G)?

ALG1 p.Asp291Glu (c.873C>G) is associated with ALG1-congenital disorder of glycosylation (ClinVar).

How common is ALG1 p.Asp291Glu (c.873C>G) in the general population?

ALG1 p.Asp291Glu (c.873C>G) is very rare (popmax 8.48e-05%, nfe) (gnomAD).

How is ALG1-CDG inherited?

Typically Autosomal recessive (Orphanet). A genetic counselor can assess individual risk for a family.

What do computational predictors say about ALG1 p.Asp291Glu (c.873C>G)?

AlphaMissense predicts likely pathogenic (score 0.865) — an in-silico prediction, not a clinical call.

ALG1 p.Asp291Glu

c.873C>G · rs1241438792 · VCV1904443

Uncertain significance Single submitter

Classification

Uncertain significance

ClinVar

Review

Single submitter ★☆☆☆

ClinVar · 1 submitter

AlphaMissense

likely pathogenic

0.865 · ACMG-weighted

gnomAD v4.1

Rare

very rare (popmax 8.48e-05%, nfe)

Missense predictors

3/3 damaging

AlphaMissense, REVEL, SaProt

Conditions

ALG1-congenital disorder of glycosylation

Computational evidence

Protein change
AlphaMissense	0.865	likely pathogenic
REVEL	0.754	pathogenic-leaning
SaProt	LLR -10.75	damaging
⇒ AlphaMissense, REVEL and SaProt all call this damaging.
Splicing
SpliceAI	—	not assessed · no allele here is in the release
Constraint at this position
Conservation	phyloP 1	GERP -0.52, phastCons 1
Regional constraint	o/e 1.27	unconstrained · MANE · 13 kb · p 3.2e-11 · regional, not allelic
Overall
CADD	25.6	PHRED · no single calibrated threshold — expert panels disagree

ClinVar classifies this uncertain; the computational predictors unanimously lean damaging — a triage signal, not a reclassification

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

Population frequency

gnomAD v4.1 · exomes + genomes

Grpmax group 8.48e-05% European (non-Finnish) · 1/1,179,690 alleles

Overall 0.000125% 2/1,599,064 alleles · very rare exomes 1/1,446,816 · genomes 1/152,248 · joint denominator

Ancestry group	Frequency	1 in
Finnishnot grpmax-eligible	0.00194%	51,546
European (non-Finnish)grpmax	8.48e-05%	1,179,690

Finnish shows a higher raw frequency than the grpmax group above it. gnomAD excludes bottlenecked groups — Finnish, Ashkenazi Jewish, Amish and “Remaining individuals” — from grpmax, because founder effects make their frequencies unrepresentative for filtering. The table is sorted by frequency, so an excluded group can sit above the grpmax row.

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: ALG1
Protein: p.Asp291Glu
Coding: c.873C>G
MANE Select: NM_019109
dbSNP: rs1241438792
Type: single nucleotide variant
Location: chr16:5079074 (GRCh38)
Gene constraint: LOEUF 1.419 · pLI <0.01 · ClinGen HI gene assoc. with recessive phenotype (gnomAD)
Structure: AlphaFold pLDDT 93.24
Residue 291: a UniProt-annotated variant site (in cdg1k; decreased function in protein glycosylation as shown by rescue assays in an alg1-deficient yeast strain)

Full ALG1 gene report on Sugi Atlas → Gene function, pathways, protein structure, interactions & more

Disease context

ALG1-congenital disorder of glycosylation — disease report on Sugi Atlas → Associated genes, phenotypes, clinical trials & treatments

For ALG1-CDG (Orphanet):

Inheritance: Autosomal recessive
Onset: Infancy, Neonatal

Similar variants

ALG1 p.Asp291Gly Uncertain significance ★ ⚠ same residue
ALG1 p.Asp291Val Uncertain significance ★ ⚠ same residue
ALG1 c.1187+1G>A Pathogenic/Likely pathogenic ★★ same condition
ALG1 c.1187+2T>C Pathogenic ★★ same condition
ALG1 c.1188-2A>G Pathogenic/Likely pathogenic ★★ same condition
ALG1 c.209-2A>G Likely pathogenic ★★ same condition
ALG1 c.539+1G>A Pathogenic/Likely pathogenic ★★ same condition
ALG1 c.630-2A>G 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/alg1-p-asp291glu (accessed [today's date]).

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