Is APC p.Pro448Arg (c.1343C>G) pathogenic?

APC p.Pro448Arg (c.1343C>G) is classified Uncertain significance in APC (ClinVar, Multiple submitters, 2 submitters; last evaluated 2023-01-01). AlphaMissense: likely pathogenic (0.9494); Absent from gnomAD v4.1; Associated with hereditary neoplastic syndrome.

What condition is associated with APC p.Pro448Arg (c.1343C>G)?

APC p.Pro448Arg (c.1343C>G) is associated with hereditary neoplastic syndrome, familial adenomatous polyposis 1 (ClinVar).

How common is APC p.Pro448Arg (c.1343C>G) in the general population?

APC p.Pro448Arg (c.1343C>G) is absent from gnomAD v4.1 (gnomAD).

What do computational predictors say about APC p.Pro448Arg (c.1343C>G)?

AlphaMissense predicts likely pathogenic (score 0.9494) — an in-silico prediction, not a clinical call.

APC p.Pro448Arg

c.1343C>G · rs1561545979 · VCV577692

Uncertain significance Multiple submitters

Classification

Uncertain significance

ClinVar

Review

Multiple submitters ★★☆☆

ClinVar · 2 submitters

AlphaMissense

likely pathogenic

0.9494 · ACMG-weighted

gnomAD v4.1

Absent

absent from gnomAD v4.1

Missense predictors

1/2 damaging

AlphaMissense, REVEL

Conditions

hereditary neoplastic syndrome

Computational evidence

Protein change
AlphaMissense	0.9494	likely pathogenic
REVEL	0.28	benign-leaning
⇒ AlphaMissense calls this damaging; REVEL does not.
Splicing
SpliceAI	—	not assessed · no allele here is in the release
Constraint at this position
Conservation	phyloP 7.7	GERP 2.9, phastCons 1
Regional constraint	o/e 0.94	unconstrained · MANE · 8,173 bp · p 0.36 · regional, not allelic
Overall
CADD	25.9	PHRED · no single calibrated threshold — expert panels disagree

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: APC
Protein: p.Pro448Arg
Coding: c.1343C>G
MANE Select: NM_000038
dbSNP: rs1561545979
Type: single nucleotide variant
Location: chr5:112821926 (GRCh38)
Gene constraint: LOEUF 0.321 · pLI 1.00 · ClinGen HI 3/3 (gnomAD)
Residue 448: an α-helix

Full APC 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

Also linked: familial adenomatous polyposis 1

Similar variants

APC p.Pro448Leu Uncertain significance ★★ same residue
APC p.Pro448Thr Uncertain significance ★★ same residue
APC p.Pro448Ala Conflicting classifications of pathogenicity ★ same residue
APC p.Pro448= Likely benign ★ same residue
APC c.1312+3A>C Likely pathogenic ★★★ same condition
APC c.1312+3A>G Pathogenic ★★★ same condition
APC c.1312+5G>A Likely pathogenic ★★★ same condition
APC c.1312+5G>C 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/apc-p-pro448arg (accessed [today's date]).

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