Is APC p.Asn20= (c.60C>T) pathogenic?

APC p.Asn20= (c.60C>T) is classified Conflicting classifications of pathogenicity in APC (ClinVar, Conflicting submitters, 8 submitters; last evaluated 2026-01-28). Very rare (popmax 0.00127%, nfe); Associated with classic or attenuated familial adenomatous polyposis.

What condition is associated with APC p.Asn20= (c.60C>T)?

APC p.Asn20= (c.60C>T) is associated with classic or attenuated familial adenomatous polyposis, hereditary neoplastic syndrome, familial adenomatous polyposis 1 (ClinVar).

How common is APC p.Asn20= (c.60C>T) in the general population?

APC p.Asn20= (c.60C>T) is very rare (popmax 0.00127%, nfe) (gnomAD).

APC p.Asn20=

c.60C>T · rs780155240 · VCV186670

Conflicting classifications of pathogenicity Conflicting submitters

Classification

Conflicting classifications of pathogenicity

ClinVar

Review

Conflicting submitters ★☆☆☆

ClinVar · 8 submitters

gnomAD v4.1

Rare

very rare (popmax 0.00127%, nfe)

Conditions

classic or attenuated familial adenomatous polyposis

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 4.8	GERP 2, phastCons 1
Overall
CADD	12.38	PHRED · no single calibrated threshold — expert panels disagree

Population frequency

gnomAD v4.1 · exomes + genomes

Grpmax group 0.00127% European (non-Finnish) · 15/1,179,760 alleles

Filtering AF 0.000763% ClinGen BA1/BS1 input FAF95, joint · FAF99 0.000605%

Overall 0.00103% 15/1,461,488 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: APC
Protein: p.Asn20=
Coding: c.60C>T
MANE Select: NM_000038
dbSNP: rs780155240
Type: single nucleotide variant
Location: chr5:112754950 (GRCh38)
Gene constraint: LOEUF 0.321 · pLI 1.00 · ClinGen HI 3/3 (gnomAD)
Residue 20: an α-helix

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

Disease context

classic or attenuated familial adenomatous polyposis — disease report on Sugi Atlas → Associated genes, phenotypes, clinical trials & treatments

Also linked: hereditary neoplastic syndrome familial adenomatous polyposis 1

Similar variants

APC p.Asn20Thr Uncertain significance ★★ same residue
APC p.Asn20Asp Uncertain significance ★ same residue
APC p.Ser20= Uncertain significance ★ same residue
APC p.Ser20Ter Uncertain significance ★ same residue
APC p.Ser20fs Uncertain significance ★ 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

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-asn20 (accessed [today's date]).

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