Is ERCC3 p.Ala120Val (c.359C>T) pathogenic?

ERCC3 p.Ala120Val (c.359C>T) is classified Uncertain significance in ERCC3 (ClinVar, Multiple submitters, 4 submitters; last evaluated 2022-09-27). AlphaMissense: likely pathogenic (0.8395); Ultra-rare (popmax 0.033%, mid); Associated with Inborn genetic diseases.

What condition is associated with ERCC3 p.Ala120Val (c.359C>T)?

ERCC3 p.Ala120Val (c.359C>T) is associated with Inborn genetic diseases, xeroderma pigmentosum group B, trichothiodystrophy 2, photosensitive (ClinVar).

How common is ERCC3 p.Ala120Val (c.359C>T) in the general population?

ERCC3 p.Ala120Val (c.359C>T) is ultra-rare (popmax 0.033%, mid) (gnomAD).

What do computational predictors say about ERCC3 p.Ala120Val (c.359C>T)?

AlphaMissense predicts likely pathogenic (score 0.8395) — an in-silico prediction, not a clinical call.

ERCC3 p.Ala120Val

c.359C>T · rs370115857 · VCV331092

Uncertain significance Multiple submitters

Classification

Uncertain significance

ClinVar

Review

Multiple submitters ★★☆☆

ClinVar · 4 submitters

AlphaMissense

likely pathogenic

0.8395 · ACMG-weighted

gnomAD v4.1

Rare

ultra-rare (popmax 0.033%, mid)

Missense predictors

2/2 damaging

AlphaMissense, SaProt · REVEL no call

Conditions

Inborn genetic diseases

Computational evidence

Protein change
AlphaMissense	0.8395	likely pathogenic
REVEL	0.5	indeterminate
SaProt	LLR -10.53	damaging
⇒ AlphaMissense and SaProt both call this damaging; REVEL makes no call.
Splicing
SpliceAI	—	not assessed · no allele here is in the release
Pangolin	Δ0.20	gain · loss 0.00 · not in the SpliceAI release · independent
Constraint at this position
Conservation	phyloP 12	GERP 2.4, phastCons 1
Regional constraint	o/e 0.84	unconstrained · MANE · 36 kb · p 4.8e-07 · regional, not allelic
Overall
CADD	26.7	PHRED · no single calibrated threshold — expert panels disagree

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

Grpmax group 0.033% Middle Eastern · 2/6,062 alleles

Filtering AF 0.00582% ClinGen BA1/BS1 input FAF95, joint · FAF99 0.00242%

Overall 0.00142% 23/1,614,102 alleles · ultra-rare

Ancestry group	Frequency	1 in
Middle Easterngrpmax	0.033%	3,031
African / African-American	0.00266%	37,529
East Asian	0.00223%	44,892
Admixed American	0.00167%	60,030
European (non-Finnish)	0.00136%	73,748
South Asian	0.0011%	91,082

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: ERCC3
Protein: p.Ala120Val
Coding: c.359C>T
MANE Select: NM_000122
dbSNP: rs370115857
Type: single nucleotide variant
Location: chr2:127292722 (GRCh38)
Gene constraint: LOEUF 0.797 · pLI <0.01 (gnomAD)
Structure: AlphaFold pLDDT 76.34 · 56 PDB
Residue 120: an α-helix

Full ERCC3 gene report on Sugi Atlas → Gene function, pathways, protein structure, interactions & more

Disease context

Inborn genetic diseases — disease report on Sugi Atlas → Associated genes, phenotypes, clinical trials & treatments

Also linked: xeroderma pigmentosum group B trichothiodystrophy 2, photosensitive

Similar variants

ERCC3 c.1828-1G>C Likely pathogenic ★★ same condition
ERCC3 c.471+1G>A Pathogenic ★★ same condition
ERCC3 c.657+1G>A Likely pathogenic ★★ same condition
ERCC3 p.Arg109Ter Pathogenic/Likely pathogenic ★★ same condition
ERCC3 p.Arg195Ter Pathogenic ★★ same condition
ERCC3 p.Arg425Ter Pathogenic ★★ same condition
ERCC3 p.Arg452Ter Pathogenic/Likely pathogenic ★★ same condition
ERCC3 p.Arg530Ter Pathogenic/Likely 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/ercc3-p-ala120val (accessed [today's date]).

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