Is FIG4 p.Arg37Cys (c.109C>T) pathogenic?

FIG4 p.Arg37Cys (c.109C>T) is classified Uncertain significance in FIG4 (ClinVar, Multiple submitters, 4 submitters; last evaluated 2025-03-28). AlphaMissense: likely pathogenic (0.7917); Very rare (popmax 0.00669%, afr); Associated with Charcot-Marie-Tooth disease type 4J.

What condition is associated with FIG4 p.Arg37Cys (c.109C>T)?

FIG4 p.Arg37Cys (c.109C>T) is associated with Charcot-Marie-Tooth disease type 4J, amyotrophic lateral sclerosis type 11, Charcot-Marie-Tooth disease type 4 (ClinVar).

How common is FIG4 p.Arg37Cys (c.109C>T) in the general population?

FIG4 p.Arg37Cys (c.109C>T) is very rare (popmax 0.00669%, afr) (gnomAD).

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

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

What do computational predictors say about FIG4 p.Arg37Cys (c.109C>T)?

AlphaMissense predicts likely pathogenic (score 0.7917) — an in-silico prediction, not a clinical call.

FIG4 p.Arg37Cys

c.109C>T · rs368625871 · VCV543424

Uncertain significance Multiple submitters

Classification

Uncertain significance

ClinVar

Review

Multiple submitters ★★☆☆

ClinVar · 4 submitters

AlphaMissense

likely pathogenic

0.7917 · ACMG-weighted

gnomAD v4.1

Rare

very rare (popmax 0.00669%, afr)

Missense predictors

3/3 damaging

AlphaMissense, REVEL, SaProt

Conditions

Charcot-Marie-Tooth disease type 4J

Computational evidence

Protein change
AlphaMissense	0.7917	likely pathogenic
REVEL	0.701	pathogenic-leaning
SaProt	LLR -12.90	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 3.3	GERP 2.6, phastCons 1
Regional constraint	o/e 0.96	unconstrained · MANE · 52 kb · p 0.42 · regional, not allelic
Overall
CADD	32.0	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

Grpmax group 0.00669% African / African-American · 5/74,738 alleles

Filtering AF 0.00276% ClinGen BA1/BS1 input FAF95, joint · FAF99 0.00245%

Overall 0.00355% 57/1,605,914 alleles · very rare exomes 48/1,453,866 · genomes 9/152,048 · joint denominator

Ancestry group	Frequency	1 in
African / African-Americangrpmax	0.00669%	14,948
Remaining individualsnot grpmax-eligible	0.00482%	20,735
European (non-Finnish)	0.00367%	27,284
South Asian	0.0033%	30,300
East Asian	0.00223%	44,752
Admixed American	0.00167%	59,940
Finnishnot grpmax-eligible	0.00157%	63,652

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: FIG4
Protein: p.Arg37Cys
Coding: c.109C>T
MANE Select: NM_014845
dbSNP: rs368625871
Type: single nucleotide variant
Location: chr6:109715120 (GRCh38)
Gene constraint: LOEUF 0.966 · pLI <0.01 (gnomAD)
Structure: AlphaFold pLDDT 80.65 · 1 PDB

Full FIG4 gene report on Sugi Atlas → Gene function, pathways, protein structure, interactions & more

Disease context

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

Also linked: amyotrophic lateral sclerosis type 11 Charcot-Marie-Tooth disease type 4

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

Inheritance: Autosomal recessive
Onset: Adult, Childhood, Infancy

Similar variants

FIG4 p.Arg37His Uncertain significance ★ ⚠ same residue
FIG4 c.1040-1G>A Likely pathogenic ★★ same condition
FIG4 c.1584-1G>T Likely pathogenic ★★ same condition
FIG4 c.1948+1G>A Likely pathogenic ★★ same condition
FIG4 c.1949-10T>G Pathogenic/Likely pathogenic ★★ same condition
FIG4 c.2376+2T>G Likely pathogenic ★★ same condition
FIG4 c.2459+1G>A Pathogenic ★★ same condition
FIG4 c.877-2A>C 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/fig4-p-arg37cys (accessed [today's date]).

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