Is ALG8 p.Ser443= (c.1329G>A) pathogenic?

ALG8 p.Ser443= (c.1329G>A) is classified Likely benign in ALG8 (ClinVar, Single submitter, 2 submitters; last evaluated 2025-10-08). Ultra-rare (popmax 0.0125%, afr); Associated with ALG8-congenital disorder of glycosylation.

What condition is associated with ALG8 p.Ser443= (c.1329G>A)?

ALG8 p.Ser443= (c.1329G>A) is associated with ALG8-congenital disorder of glycosylation (ClinVar).

How common is ALG8 p.Ser443= (c.1329G>A) in the general population?

ALG8 p.Ser443= (c.1329G>A) is ultra-rare (popmax 0.0125%, afr) (gnomAD).

How is ALG8-CDG inherited?

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

ALG8 p.Ser443=

c.1329G>A · rs541273577 · VCV3031593

Likely benign Single submitter

Classification

Likely benign

ClinVar

Review

Single submitter ★☆☆☆

ClinVar · 2 submitters

gnomAD v4.1

Rare

ultra-rare (popmax 0.0125%, afr)

Conditions

ALG8-congenital disorder of glycosylation

Computational evidence

Protein change
Missense predictors do not apply to this variant type; conservation carries the signal.
REVEL	0.019	moderately benign-leaning
Splicing
SpliceAI	—	not assessed · no allele here is in the release
Constraint at this position
Conservation	phyloP 0.53	GERP -3.1, phastCons 0.99
Overall
CADD	8.132	PHRED · no single calibrated threshold — expert panels disagree

Population frequency

gnomAD v4.1 · exomes + genomes

Grpmax group 0.0125% African / African-American · 9/72,286 alleles

Filtering AF 0.00644% ClinGen BA1/BS1 input FAF95, joint · FAF99 0.00482%

Overall 0.00275% 41/1,493,296 alleles · ultra-rare

Ancestry group	Frequency	1 in
African / African-Americangrpmax	0.0125%	8,032
East Asian	0.00684%	14,629
European (non-Finnish)	0.00242%	41,379
Admixed American	0.00171%	58,512
Finnishnot grpmax-eligible	0.00158%	63,096
South Asian	0.00116%	86,430

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: ALG8
Protein: p.Ser443=
Coding: c.1329G>A
MANE Select: NM_024079
dbSNP: rs541273577
Type: single nucleotide variant
Location: chr11:78104000 (GRCh38)
Gene constraint: LOEUF 0.909 · pLI <0.01 (gnomAD)
Structure: AlphaFold pLDDT 92.07
Residue 443: a UniProt-annotated variant site (in pcld3)

Full ALG8 gene report on Sugi Atlas → Gene function, pathways, protein structure, interactions & more

Disease context

ALG8-congenital disorder of glycosylation — disease report on Sugi Atlas → Associated genes, phenotypes, clinical trials & treatments

For ALG8-CDG (Orphanet):

Inheritance: Autosomal recessive
Onset: Antenatal, Infancy, Neonatal

Similar variants

ALG8 p.Ser443Leu Uncertain significance ★★ ⚠ same residue
ALG8 p.Ser443Ter Uncertain significance ★ same residue
ALG8 c.368+2T>G Likely pathogenic ★★ same condition
ALG8 c.674-2A>G Likely pathogenic ★★ same condition
ALG8 c.777+1G>A Likely pathogenic ★★ same condition
ALG8 c.95+1G>A Likely pathogenic ★★ same condition
ALG8 p.Arg179Ter Pathogenic/Likely pathogenic ★★ same condition
ALG8 p.Arg229Ter Pathogenic/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/alg8-p-ser443 (accessed [today's date]).

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