Is ADAR p.Arg866= (c.2598C>G) pathogenic?

ADAR p.Arg866= (c.2598C>G) is classified Likely benign in ADAR (ClinVar, Multiple submitters, 3 submitters; last evaluated 2025-08-04). Ultra-rare (popmax 0.0176%, sas); Associated with dyschromatosis symmetrica hereditaria.

What condition is associated with ADAR p.Arg866= (c.2598C>G)?

ADAR p.Arg866= (c.2598C>G) is associated with dyschromatosis symmetrica hereditaria, Aicardi-Goutieres syndrome 6 (ClinVar).

How common is ADAR p.Arg866= (c.2598C>G) in the general population?

ADAR p.Arg866= (c.2598C>G) is ultra-rare (popmax 0.0176%, sas) (gnomAD).

How is Dyschromatosis symmetrica hereditaria inherited?

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

ADAR p.Arg866=

c.2598C>G · rs749389266 · VCV1613618

Likely benign Multiple submitters

Classification

Likely benign

ClinVar

Review

Multiple submitters ★★☆☆

ClinVar · 3 submitters

gnomAD v4.1

Rare

ultra-rare (popmax 0.0176%, sas)

Conditions

dyschromatosis symmetrica hereditaria

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 -3.2, phastCons 1
Overall
CADD	8.077	PHRED · no single calibrated threshold — expert panels disagree

Population frequency

gnomAD v4.1 · exomes + genomes

Grpmax group 0.0176% South Asian · 16/91,076 alleles

Filtering AF 0.011% ClinGen BA1/BS1 input FAF95, joint · FAF99 0.00888%

Overall 0.00164% 24/1,461,866 alleles · ultra-rare

Ancestry group	Frequency	1 in
South Asiangrpmax	0.0176%	5,692
Remaining individualsnot grpmax-eligible	0.0128%	7,813

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: ADAR
Protein: p.Arg866=
Coding: c.2598C>G
MANE Select: NM_001111
dbSNP: rs749389266
Type: single nucleotide variant
Location: chr1:154589827 (GRCh38)
Gene constraint: LOEUF 0.449 · pLI 1.00 (gnomAD)
Structure: AlphaFold pLDDT 68.86 · 24 PDB

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

Disease context

dyschromatosis symmetrica hereditaria — disease report on Sugi Atlas → Associated genes, phenotypes, clinical trials & treatments

Also linked: Aicardi-Goutieres syndrome 6

For Dyschromatosis symmetrica hereditaria (Orphanet):

Inheritance: Autosomal dominant
Onset: Childhood

Similar variants

ADAR p.Arg866Cys Uncertain significance ★ ⚠ same residue
ADAR p.Arg866His Conflicting classifications of pathogenicity ★ ⚠ same residue
ADAR c.2885+1G>A Likely pathogenic ★★ same condition
ADAR p.Arg1078Cys Pathogenic ★★ same condition
ADAR p.Arg1096Ter Pathogenic/Likely pathogenic ★★ same condition
ADAR p.Arg328Ter Pathogenic ★★ same condition
ADAR p.Arg360Ter Pathogenic/Likely pathogenic ★★ same condition
ADAR p.Arg474Ter 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/adar-p-arg866 (accessed [today's date]).

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