Is ADAR p.His642= (c.1926T>C) pathogenic?

ADAR p.His642= (c.1926T>C) is classified Benign/Likely benign in ADAR (ClinVar, Multiple submitters, 11 submitters; last evaluated 2026-02-02). Rare (popmax 0.347%, mid); Associated with Aicardi-Goutieres syndrome 6.

What condition is associated with ADAR p.His642= (c.1926T>C)?

ADAR p.His642= (c.1926T>C) is associated with Aicardi-Goutieres syndrome 6, dyschromatosis symmetrica hereditaria (ClinVar).

How common is ADAR p.His642= (c.1926T>C) in the general population?

ADAR p.His642= (c.1926T>C) is rare (popmax 0.347%, mid) (gnomAD).

How is Aicardi-Goutières syndrome inherited?

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

ADAR p.His642=

c.1926T>C · rs150171059 · VCV292771

Benign/Likely benign Multiple submitters

Classification

Benign/Likely benign

ClinVar

Review

Multiple submitters ★★☆☆

ClinVar · 11 submitters

gnomAD v4.1

Rare

rare (popmax 0.347%, mid)

Conditions

Aicardi-Goutieres syndrome 6

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 -0.076	GERP -1.4, phastCons 0.007
Overall
CADD	5.619	PHRED · no single calibrated threshold — expert panels disagree

Population frequency

gnomAD v4.1 · exomes + genomes

Grpmax group 0.347% Middle Eastern · 21/6,046 alleles

Filtering AF 0.233% ClinGen BA1/BS1 input FAF95, joint · FAF99 0.196%

Overall 0.165% 2,670/1,614,142 alleles · rare

Ancestry group	Frequency	1 in
Middle Easterngrpmax	0.347%	288
European (non-Finnish)	0.194%	517
Admixed American	0.192%	522
Remaining individualsnot grpmax-eligible	0.147%	679
South Asian	0.139%	717
Amishnot grpmax-eligible	0.11%	912
African / African-American	0.0373%	2,680
Ashkenazi Jewishnot grpmax-eligible	0.00338%	29,608
Finnishnot grpmax-eligible	0.00156%	64,042

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.His642=
Coding: c.1926T>C
MANE Select: NM_001111
dbSNP: rs150171059
Type: single nucleotide variant
Location: chr1:154597836 (GRCh38)
Gene constraint: LOEUF 0.449 · pLI 1.00 (gnomAD)
Structure: AlphaFold pLDDT 68.86 · 24 PDB
Residue 642: the drbm 2 domain

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

Disease context

Aicardi-Goutieres syndrome 6 — disease report on Sugi Atlas → Associated genes, phenotypes, clinical trials & treatments

Also linked: dyschromatosis symmetrica hereditaria

For Aicardi-Goutières syndrome (Orphanet):

Inheritance: Autosomal dominant, Autosomal recessive
Onset: Antenatal, Infancy, Neonatal
Prevalence: 1-5 / 10 000 (Europe)

Similar variants

ADAR p.His642Arg Uncertain significance ★ ⚠ same residue
ADAR p.His642Tyr Uncertain significance ★ ⚠ 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-his642 (accessed [today's date]).

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