Is DDOST p.Ile169= (c.507C>T) pathogenic?

DDOST p.Ile169= (c.507C>T) is classified Likely benign in DDOST (ClinVar, Multiple submitters, 2 submitters; last evaluated 2025-06-27). Very rare (popmax 0.00127%, nfe); Associated with DDOST-congenital disorder of glycosylation.

What condition is associated with DDOST p.Ile169= (c.507C>T)?

DDOST p.Ile169= (c.507C>T) is associated with DDOST-congenital disorder of glycosylation (ClinVar).

How common is DDOST p.Ile169= (c.507C>T) in the general population?

DDOST p.Ile169= (c.507C>T) is very rare (popmax 0.00127%, nfe) (gnomAD).

How is DDOST-CDG inherited?

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

DDOST p.Ile169=

c.507C>T · rs149487745 · VCV508378

Likely benign Multiple submitters

Classification

Likely benign

ClinVar

Review

Multiple submitters ★★☆☆

ClinVar · 2 submitters

gnomAD v4.1

Rare

very rare (popmax 0.00127%, nfe)

Conditions

DDOST-congenital disorder of glycosylation

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 -2.3	GERP -5.1
Overall
CADD	7.717	PHRED · no single calibrated threshold — expert panels disagree

Population frequency

gnomAD v4.1 · exomes + genomes

Grpmax group 0.00127% European (non-Finnish) · 15/1,179,948 alleles

Filtering AF 0.000763% ClinGen BA1/BS1 input FAF95, joint · FAF99 0.000605%

Overall 0.00105% 17/1,613,890 alleles · very rare

Ancestry group	Frequency	1 in
Remaining individualsnot grpmax-eligible	0.0016%	62,484
European (non-Finnish)grpmax	0.00127%	78,663
South Asian	0.0011%	91,072

Remaining individuals 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: DDOST
Protein: p.Ile169=
Coding: c.507C>T
MANE Select: NM_005216
dbSNP: rs149487745
Type: single nucleotide variant
Location: chr1:20655484 (GRCh38)
Gene constraint: LOEUF 0.747 · pLI <0.01 · ClinGen HI gene assoc. with recessive phenotype (gnomAD)
Structure: AlphaFold pLDDT 89.27 · 6 PDB
Residue 169: a β-strand

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

Disease context

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

For DDOST-CDG (Orphanet):

Inheritance: Autosomal recessive
Onset: Infancy, Neonatal

Similar variants

DDOST p.Gln215His Pathogenic/Likely pathogenic ★★ ⚠ same condition
DDOST c.-18T>G Uncertain significance ★★ ⚠ same condition
DDOST p.Ala11Val Uncertain significance ★★ ⚠ same condition
DDOST p.Ala219Val Uncertain significance ★★ ⚠ same condition
DDOST p.Ala232Ser Uncertain significance ★★ ⚠ same condition
DDOST p.Ala415Thr Uncertain significance ★★ ⚠ same condition
DDOST p.Arg237His Uncertain significance ★★ ⚠ same condition
DDOST p.Arg280Cys 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/ddost-p-ile169 (accessed [today's date]).

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