Is ABCA4 p.Ser1099Ter (c.3296C>G) pathogenic?

ABCA4 p.Ser1099Ter (c.3296C>G) is classified Pathogenic in ABCA4 (ClinVar, Multiple submitters, 2 submitters; last evaluated 2022-04-12). Absent from gnomAD v4.1; Associated with severe early-childhood-onset retinal dystrophy.

What condition is associated with ABCA4 p.Ser1099Ter (c.3296C>G)?

ABCA4 p.Ser1099Ter (c.3296C>G) is associated with severe early-childhood-onset retinal dystrophy (ClinVar).

How common is ABCA4 p.Ser1099Ter (c.3296C>G) in the general population?

ABCA4 p.Ser1099Ter (c.3296C>G) is absent from gnomAD v4.1 (gnomAD).

How is Severe early-childhood-onset retinal dystrophy inherited?

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

ABCA4 p.Ser1099Ter

c.3296C>G · rs776773510 · VCV1213969

Pathogenic Multiple submitters

Classification

Pathogenic

ClinVar

Review

Multiple submitters ★★☆☆

ClinVar · 2 submitters

Consequence

nonsense (stop-gain)

predicted LoF

gnomAD v4.1

Absent

absent from gnomAD v4.1

Conditions

severe early-childhood-onset retinal dystrophy

Computational evidence

Protein change
Missense predictors do not apply to this variant type; conservation carries the signal.
Consequence	nonsense (stop-gain)	predicted loss-of-function
NMD	predicted	premature termination codon in exon 22 of 50
Splicing
SpliceAI	—	not assessed · no allele here is in the release
Constraint at this position
Conservation	phyloP 8.6	GERP 1.7, phastCons 1
Overall
CADD	38.0	PHRED · no single calibrated threshold — expert panels disagree

Predicted loss-of-function is descriptive, not an applied PVS1 code.

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: ABCA4
Protein: p.Ser1099Ter
Coding: c.3296C>G
MANE Select: NM_000350
dbSNP: rs776773510
Type: single nucleotide variant
Location: chr1:94042793 (GRCh38)
Gene constraint: LOEUF 0.786 · pLI <0.01 (gnomAD)
Structure: AlphaFold pLDDT 75.96 · 8 PDB
Residue 1099: a UniProt-annotated variant site (in cord3; uncertain significance); a UniProt-annotated variant site (in stgd1; uncertain significance); a UniProt-annotated variant site (found in a patient with chorioretinal atrophy; uncertain significance); a UniProt-annotated variant site (found in a patient with macular dystrophy; uncertain significance); the abc transporter 1 domain; an α-helix; a disulfide bond

Full ABCA4 gene report on Sugi Atlas → Gene function, pathways, protein structure, interactions & more

Disease context

severe early-childhood-onset retinal dystrophy — disease report on Sugi Atlas → Associated genes, phenotypes, clinical trials & treatments

For Severe early-childhood-onset retinal dystrophy (Orphanet):

Inheritance: Autosomal recessive
Onset: Childhood, Infancy

Similar variants

ABCA4 p.Ser1099= Benign/Likely benign ★★ same residue
ABCA4 p.Ser1099Pro Pathogenic ★ same residue
ABCA4 c.1937+1G>A Pathogenic ★★★ same condition
ABCA4 c.3523-1G>A Pathogenic ★★★ same condition
ABCA4 c.4253+43G>A Pathogenic ★★★ same condition
ABCA4 c.4254-1G>C Pathogenic ★★★ same condition
ABCA4 c.4352+1G>A Pathogenic ★★★ same condition
ABCA4 c.4773+3A>G 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/abca4-p-ser1099ter (accessed [today's date]).

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