Is LIG4 p.Arg25= (c.75A>G) pathogenic?

LIG4 p.Arg25= (c.75A>G) is classified Likely benign in LIG4 (ClinVar, Single submitter, 1 submitter; last evaluated 2025-09-14). Very rare (popmax 6.84e-05%); Associated with DNA ligase IV deficiency.

What condition is associated with LIG4 p.Arg25= (c.75A>G)?

LIG4 p.Arg25= (c.75A>G) is associated with DNA ligase IV deficiency (ClinVar).

How common is LIG4 p.Arg25= (c.75A>G) in the general population?

LIG4 p.Arg25= (c.75A>G) is very rare (popmax 6.84e-05%) (gnomAD).

How is LIG4 syndrome inherited?

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

LIG4 p.Arg25=

c.75A>G · VCV4727139

Likely benign Single submitter

Classification

Likely benign

ClinVar

Review

Single submitter ★☆☆☆

ClinVar · 1 submitter

gnomAD v4.1

Rare

very rare (popmax 6.84e-05%)

Conditions

DNA ligase IV deficiency

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 -0.13	GERP -4.4, phastCons 0.75
Overall
CADD	8.533	PHRED · no single calibrated threshold — expert panels disagree

Population frequency

gnomAD v4.1 · exomes + genomes

Grpmax group 6.84e-05%

Overall 6.84e-05% 1/1,461,176 alleles · very rare

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: LIG4
Protein: p.Arg25=
Coding: c.75A>G
MANE Select: NM_206937
Type: single nucleotide variant
Location: chr13:108211194 (GRCh38)
Gene constraint: LOEUF 1.043 · pLI <0.01 · ClinGen HI gene assoc. with recessive phenotype (gnomAD)
Structure: AlphaFold pLDDT 88.44 · 32 PDB
Residue 25: an α-helix

Full LIG4 gene report on Sugi Atlas → Gene function, pathways, protein structure, interactions & more

Disease context

DNA ligase IV deficiency — disease report on Sugi Atlas → Associated genes, phenotypes, clinical trials & treatments

For LIG4 syndrome (Orphanet):

Inheritance: Autosomal recessive
Onset: Infancy, Neonatal

Similar variants

LIG4 p.Arg25Gln Uncertain significance ★★ ⚠ same residue
LIG4 p.Arg25Ter Pathogenic ★ same residue
LIG4 p.Arg278His Pathogenic ★★ same condition
LIG4 p.Arg278Leu Pathogenic ★★ same condition
LIG4 p.Arg293Ter Pathogenic/Likely pathogenic ★★ same condition
LIG4 p.Arg580Ter Pathogenic/Likely pathogenic ★★ same condition
LIG4 p.Arg814Ter Pathogenic/Likely pathogenic ★★ same condition
LIG4 p.Gln74Ter 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/lig4-p-arg25 (accessed [today's date]).

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