Is ALG12 p.Ala356= (c.1068C>T) pathogenic?

ALG12 p.Ala356= (c.1068C>T) is classified Likely benign in ALG12 (ClinVar, Single submitter, 2 submitters; last evaluated 2025-08-08). Ultra-rare (popmax 0.068%, afr); Associated with ALG12-congenital disorder of glycosylation.

What condition is associated with ALG12 p.Ala356= (c.1068C>T)?

ALG12 p.Ala356= (c.1068C>T) is associated with ALG12-congenital disorder of glycosylation (ClinVar).

How common is ALG12 p.Ala356= (c.1068C>T) in the general population?

ALG12 p.Ala356= (c.1068C>T) is ultra-rare (popmax 0.068%, afr) (gnomAD).

How is ALG12-CDG inherited?

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

ALG12 p.Ala356=

c.1068C>T · rs371321442 · VCV732151

Likely benign Single submitter

Classification

Likely benign

ClinVar

Review

Single submitter ★☆☆☆

ClinVar · 2 submitters

gnomAD v4.1

Rare

ultra-rare (popmax 0.068%, afr)

Conditions

ALG12-congenital disorder of glycosylation

Computational evidence

Protein change
Missense predictors do not apply to this variant type; conservation carries the signal.
REVEL	0.077	moderately benign-leaning
Splicing
SpliceAI	—	not assessed · no allele here is in the release
Constraint at this position
Conservation	phyloP -2.5	GERP -3
Overall
CADD	2.569	PHRED · no single calibrated threshold — expert panels disagree

Population frequency

gnomAD v4.1 · exomes + genomes

Grpmax group 0.068% African / African-American · 51/75,022 alleles

Filtering AF 0.0531% ClinGen BA1/BS1 input FAF95, joint · FAF99 0.0478%

Overall 0.00415% 67/1,614,146 alleles · ultra-rare

Ancestry group	Frequency	1 in
African / African-Americangrpmax	0.068%	1,471
Admixed American	0.00666%	15,006
Remaining individualsnot grpmax-eligible	0.0032%	31,255
South Asian	0.0011%	91,076
European (non-Finnish)	0.000763%	131,115

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: ALG12
Protein: p.Ala356=
Coding: c.1068C>T
MANE Select: NM_024105
dbSNP: rs371321442
Type: single nucleotide variant
Location: chr22:49904431 (GRCh38)
Gene constraint: LOEUF 0.965 · pLI <0.01 · ClinGen HI gene assoc. with recessive phenotype (gnomAD)
Structure: AlphaFold pLDDT 93.26

Full ALG12 gene report on Sugi Atlas → Gene function, pathways, protein structure, interactions & more

Disease context

ALG12-congenital disorder of glycosylation — disease report on Sugi Atlas → Associated genes, phenotypes, clinical trials & treatments

For ALG12-CDG (Orphanet):

Inheritance: Autosomal recessive
Onset: Infancy, Neonatal

Similar variants

ALG12 p.Ala356Val Uncertain significance ★ ⚠ same residue
ALG12 c.295+1G>A Pathogenic/Likely pathogenic ★★ same condition
ALG12 c.768+1G>A Likely pathogenic ★★ same condition
ALG12 p.Arg146Gln Pathogenic/Likely pathogenic ★★ same condition
ALG12 p.Arg202Ter Pathogenic/Likely pathogenic ★★ same condition
ALG12 p.Gly101Arg Likely pathogenic ★★ same condition
ALG12 p.Thr67Met Pathogenic/Likely pathogenic ★★ same condition
ALG12 c.469+5G>A Uncertain significance ★★ 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/alg12-p-ala356 (accessed [today's date]).

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