Is DHDDS p.Ser88Asn (c.263G>A) pathogenic?

DHDDS p.Ser88Asn (c.263G>A) is classified Uncertain significance in DHDDS (ClinVar, No assertion criteria, 1 submitter; last evaluated 2022-01-01). AlphaMissense: likely benign (0.0689); Absent from gnomAD v4.1; Associated with inherited retinal dystrophy.

What condition is associated with DHDDS p.Ser88Asn (c.263G>A)?

DHDDS p.Ser88Asn (c.263G>A) is associated with inherited retinal dystrophy (ClinVar).

How common is DHDDS p.Ser88Asn (c.263G>A) in the general population?

DHDDS p.Ser88Asn (c.263G>A) is absent from gnomAD v4.1 (gnomAD).

What do computational predictors say about DHDDS p.Ser88Asn (c.263G>A)?

AlphaMissense predicts likely benign (score 0.0689) — an in-silico prediction, not a clinical call.

DHDDS p.Ser88Asn

c.263G>A · VCV3249409

Uncertain significance No assertion criteria

Classification

Uncertain significance

ClinVar

Review

No assertion criteria ☆☆☆☆

ClinVar · 1 submitter

AlphaMissense

likely benign

0.0689 · ACMG-weighted

gnomAD v4.1

Absent

absent from gnomAD v4.1

Missense predictors

0/3 damaging

AlphaMissense, REVEL, SaProt

Conditions

inherited retinal dystrophy

Computational evidence

Protein change
AlphaMissense	0.0689	likely benign
REVEL	0.151	moderately benign-leaning
SaProt	LLR -7.26	tolerated
⇒ AlphaMissense, REVEL and SaProt all call this tolerated.
Splicing
SpliceAI	—	not assessed · no allele here is in the release
Constraint at this position
Conservation	phyloP 4.1	GERP -0.096, phastCons 1
Regional constraint	o/e 0.58	unconstrained · MANE · 9,886 bp · p 3.6e-06 · regional, not allelic
Overall
CADD	19.72	PHRED · no single calibrated threshold — expert panels disagree

ClinVar classifies this uncertain; the computational predictors unanimously lean tolerated — 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

Absent from gnomAD v4.1. Not observed in any sequenced alleles — a rarity signal (ACMG PM2-supporting), not evidence of pathogenicity on its own.

Variant & gene context

Gene: DHDDS
Protein: p.Ser88Asn
Coding: c.263G>A
MANE Select: NM_205861
Type: single nucleotide variant
Location: chr1:26442813 (GRCh38)
Gene constraint: LOEUF 0.536 · pLI 0.91 (gnomAD)
Structure: AlphaFold pLDDT 95.01 · 9 PDB
Residue 88: a UniProt-annotated variant site (in rp59; in a patient with congenital disorder of glycosylation); an α-helix

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

Disease context

inherited retinal dystrophy — disease report on Sugi Atlas → Associated genes, phenotypes, clinical trials & treatments

Similar variants

DHDDS p.Ser88Gly Uncertain significance ★ ⚠ same residue
DHDDS p.Ser88= Likely benign ★ same residue
DHDDS p.Ser88fs Pathogenic/Likely pathogenic ★★ same residue
DHDDS p.Ala77Thr Uncertain significance ★★ ⚠ same condition
DHDDS p.Arg327Cys Uncertain significance ★★ ⚠ same condition
DHDDS p.Asp123Asn Uncertain significance ★★ ⚠ same condition
DHDDS p.Asp323Glu Uncertain significance ★★ ⚠ same condition
DHDDS p.Leu254Pro 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/dhdds-p-ser88asn (accessed [today's date]).

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