Is ALG13 p.Ser12= (c.36C>T) pathogenic?

ALG13 p.Ser12= (c.36C>T) is classified Likely benign in ALG13 (ClinVar, Single submitter, 1 submitter; last evaluated 2023-10-15). Very rare (popmax 0.00175%, sas); Associated with developmental and epileptic encephalopathy, 36.

What condition is associated with ALG13 p.Ser12= (c.36C>T)?

ALG13 p.Ser12= (c.36C>T) is associated with developmental and epileptic encephalopathy, 36 (ClinVar).

How common is ALG13 p.Ser12= (c.36C>T) in the general population?

ALG13 p.Ser12= (c.36C>T) is very rare (popmax 0.00175%, sas) (gnomAD).

How is ALG13-CDG inherited?

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

ALG13 p.Ser12=

c.36C>T · rs1933034901 · VCV2768690

Likely benign Single submitter

Classification

Likely benign

ClinVar

Review

Single submitter ★☆☆☆

ClinVar · 1 submitter

gnomAD v4.1

Rare

very rare (popmax 0.00175%, sas)

Conditions

developmental and epileptic encephalopathy, 36

Computational evidence

Protein change
Missense predictors do not apply to this variant type; conservation carries the signal.
Splicing
SpliceAI	—	not assessed · no allele here is in the release
Constraint at this position
Conservation	phyloP 0.28	GERP -0.87, phastCons 0.99
Overall
CADD	14.13	PHRED · no single calibrated threshold — expert panels disagree

Population frequency

gnomAD v4.1 · exomes + genomes

Grpmax group 0.00175% South Asian · 1/57,028 alleles

Overall 8.25e-05% 1/1,212,363 alleles · very rare exomes 1/1,098,138 · genomes 0/114,225 · joint denominator

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: ALG13
Protein: p.Ser12=
Coding: c.36C>T
MANE Select: NM_001099922
dbSNP: rs1933034901
Type: single nucleotide variant
Location: chrX:111681254 (GRCh38)
Structure: AlphaFold pLDDT 54.42
Residue 12: the 'glycosyltransferase activity' region

Full ALG13 gene report on Sugi Atlas → Gene function, pathways, protein structure, interactions & more

Disease context

developmental and epileptic encephalopathy, 36 — disease report on Sugi Atlas → Associated genes, phenotypes, clinical trials & treatments

For ALG13-CDG (Orphanet):

Inheritance: X-linked recessive
Onset: Infancy, Neonatal

Similar variants

ALG13 p.Ser12Asn Uncertain significance ★ ⚠ same residue
ALG13 p.Asn107Ser Pathogenic/Likely pathogenic ★★ ⚠ same condition
ALG13 c.2458-1G>A Uncertain significance ★★ same condition
ALG13 c.2695+4G>A Uncertain significance ★★ same condition
ALG13 c.2932+6T>C Uncertain significance ★★ same condition
ALG13 c.834+3A>G Uncertain significance ★★ same condition
ALG13 c.932+2T>C Uncertain significance ★★ same condition
ALG13 p.Ala1044Thr 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/alg13-p-ser12 (accessed [today's date]).

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