Is GDAP1 p.Gly331Arg (c.991G>A) pathogenic?

GDAP1 p.Gly331Arg (c.991G>A) is classified Uncertain significance in GDAP1 (ClinVar, Single submitter, 1 submitter; last evaluated 2025-03-30). AlphaMissense: likely pathogenic (0.9889); Absent from gnomAD v4.1; Associated with Charcot-Marie-Tooth disease type 4A.

What condition is associated with GDAP1 p.Gly331Arg (c.991G>A)?

GDAP1 p.Gly331Arg (c.991G>A) is associated with Charcot-Marie-Tooth disease type 4A (ClinVar).

How common is GDAP1 p.Gly331Arg (c.991G>A) in the general population?

GDAP1 p.Gly331Arg (c.991G>A) is absent from gnomAD v4.1 (gnomAD).

How is Charcot-Marie-Tooth disease type 4A inherited?

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

What do computational predictors say about GDAP1 p.Gly331Arg (c.991G>A)?

AlphaMissense predicts likely pathogenic (score 0.9889) — an in-silico prediction, not a clinical call.

GDAP1 p.Gly331Arg

c.991G>A · VCV4805932

Uncertain significance Single submitter

Classification

Uncertain significance

ClinVar

Review

Single submitter ★☆☆☆

ClinVar · 1 submitter

AlphaMissense

likely pathogenic

0.9889 · ACMG-weighted

gnomAD v4.1

Absent

absent from gnomAD v4.1

Missense predictors

3/3 damaging

AlphaMissense, REVEL, SaProt

Conditions

Charcot-Marie-Tooth disease type 4A

Computational evidence

Protein change
AlphaMissense	0.9889	likely pathogenic · top 9% in GDAP1
REVEL	0.809	moderately pathogenic-leaning
SaProt	LLR -12.10	damaging
⇒ AlphaMissense, REVEL and SaProt all call this damaging.
Splicing
SpliceAI	—	not assessed · no allele here is in the release
Constraint at this position
Conservation	phyloP 12	GERP 2.8, phastCons 1
Regional constraint	o/e 0.86	unconstrained · MANE · 14 kb · p 0.0041 · regional, not allelic
Overall
CADD	31.0	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

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: GDAP1
Protein: p.Gly331Arg
Coding: c.991G>A
MANE Select: NM_018972
Type: single nucleotide variant
Location: chr8:74364281 (GRCh38)
Gene constraint: LOEUF 0.963 · pLI <0.01 (gnomAD)
Structure: AlphaFold pLDDT 87.68 · 8 PDB
Residue 331: the 'required for mitochondrial localization' region

Full GDAP1 gene report on Sugi Atlas → Gene function, pathways, protein structure, interactions & more

Disease context

Charcot-Marie-Tooth disease type 4A — disease report on Sugi Atlas → Associated genes, phenotypes, clinical trials & treatments

For Charcot-Marie-Tooth disease type 4A (Orphanet):

Inheritance: Autosomal recessive
Onset: Infancy, Neonatal

Similar variants

GDAP1 p.Gly331del Uncertain significance ★ same residue
GDAP1 c.311-1G>A Pathogenic/Likely pathogenic ★★ same condition
GDAP1 c.579+1G>A Pathogenic ★★ same condition
GDAP1 c.694+1G>A Pathogenic/Likely pathogenic ★★ same condition
GDAP1 p.Arg120Trp Pathogenic ★★ ⚠ same condition
GDAP1 p.Arg125Ter Pathogenic ★★ same condition
GDAP1 p.Arg161His Pathogenic/Likely pathogenic ★★ ⚠ same condition
GDAP1 p.Arg191Ter 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/gdap1-p-gly331arg (accessed [today's date]).

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