Is FH p.Arg3= (c.9A>G) pathogenic?

FH p.Arg3= (c.9A>G) is classified Likely benign in FH (ClinVar, Single submitter, 1 submitter; last evaluated 2022-10-21). Absent from gnomAD v4.1; Associated with hereditary neoplastic syndrome.

What condition is associated with FH p.Arg3= (c.9A>G)?

FH p.Arg3= (c.9A>G) is associated with hereditary neoplastic syndrome (ClinVar).

How common is FH p.Arg3= (c.9A>G) in the general population?

FH p.Arg3= (c.9A>G) is absent from gnomAD v4.1 (gnomAD).

FH p.Arg3=

c.9A>G · rs941921568 · VCV1768907

Likely benign Single submitter

Classification

Likely benign

ClinVar

Review

Single submitter ★☆☆☆

ClinVar · 1 submitter

gnomAD v4.1

Absent

absent from gnomAD v4.1

Conditions

hereditary neoplastic syndrome

Computational evidence

Protein change
Missense predictors do not apply to this variant type; conservation carries the signal.
Splicing
SpliceAI	<0.2	no splice effect predicted · four deltas, not one · how we know
Constraint at this position
Conservation	phyloP -1.8	GERP -3.8
Overall
CADD	7.903	PHRED · no single calibrated threshold — expert panels disagree

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: FH
Protein: p.Arg3=
Coding: c.9A>G
MANE Select: NM_000143
dbSNP: rs941921568
Type: single nucleotide variant
Location: chr1:241519714 (GRCh38)
Gene constraint: LOEUF 0.599 · pLI 0.27 · ClinGen HI 3/3 (gnomAD)
Structure: AlphaFold pLDDT 92.92 · 8 PDB

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

Disease context

hereditary neoplastic syndrome — disease report on Sugi Atlas → Associated genes, phenotypes, clinical trials & treatments

Similar variants

FH p.Arg3Gln Uncertain significance ★★ ⚠ same residue
FH p.Arg3Pro Uncertain significance ★★ ⚠ same residue
FH p.Arg3Gly Conflicting classifications of pathogenicity ★ ⚠ same residue
FH p.Arg3Ter Conflicting classifications of pathogenicity ★ ⚠ same residue
FH p.Arg3fs Uncertain significance ★ same residue
FH c.1108+1G>T Pathogenic/Likely pathogenic ★★ same condition
FH c.1236+1G>A Pathogenic/Likely pathogenic ★★ same condition
FH c.1236+1G>C 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/fh-p-arg3 (accessed [today's date]).

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