Is CDKN2A p.Ala86Ser (c.256G>T) pathogenic?

CDKN2A p.Ala86Ser (c.256G>T) is classified Uncertain significance in CDKN2A (ClinVar, Multiple submitters, 3 submitters; last evaluated 2024-08-22). AlphaMissense: likely benign (0.281); Very rare (popmax 8.48e-05%, nfe); Associated with hereditary neoplastic syndrome.

What condition is associated with CDKN2A p.Ala86Ser (c.256G>T)?

CDKN2A p.Ala86Ser (c.256G>T) is associated with hereditary neoplastic syndrome, melanoma and neural system tumor syndrome (ClinVar).

How common is CDKN2A p.Ala86Ser (c.256G>T) in the general population?

CDKN2A p.Ala86Ser (c.256G>T) is very rare (popmax 8.48e-05%, nfe) (gnomAD).

What do computational predictors say about CDKN2A p.Ala86Ser (c.256G>T)?

AlphaMissense predicts likely benign (score 0.281) — an in-silico prediction, not a clinical call.

CDKN2A p.Ala86Ser

c.256G>T · rs1190283873 · VCV1793230

Uncertain significance Multiple submitters

Classification

Uncertain significance

ClinVar

Review

Multiple submitters ★★☆☆

ClinVar · 3 submitters

AlphaMissense

likely benign

0.281 · ACMG-weighted

gnomAD v4.1

Rare

very rare (popmax 8.48e-05%, nfe)

Missense predictors

1/2 damaging

AlphaMissense, SaProt · REVEL no call

Conditions

hereditary neoplastic syndrome

Computational evidence

Protein change
AlphaMissense	0.281	likely benign
REVEL	0.39	indeterminate
SaProt	LLR -10.83	damaging
⇒ SaProt calls this damaging; AlphaMissense does not; REVEL makes no call.
Splicing
SpliceAI	—	not assessed · no allele here is in the release
Constraint at this position
Conservation	phyloP 7.5	GERP 2, phastCons 1
Regional constraint	o/e 1.13	unconstrained · MANE · 6,595 bp · p 0.04 · regional, not allelic
Overall
CADD	26.3	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

Grpmax group 8.48e-05% European (non-Finnish) · 1/1,179,570 alleles

Overall 6.89e-05% 1/1,452,234 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: CDKN2A
Protein: p.Ala86Ser
Coding: c.256G>T
MANE Select: NM_000077
dbSNP: rs1190283873
Type: single nucleotide variant
Location: chr9:21971103 (GRCh38)
Gene constraint: LOEUF 0.791 · pLI 0.62 · ClinGen HI 3/3 (gnomAD)
Structure: AlphaFold pLDDT 77.02 · 5 PDB
Residue 86: an α-helix; the 'disordered' region

Full CDKN2A 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: melanoma and neural system tumor syndrome

Similar variants

CDKN2A p.Ala86Gly Uncertain significance ★ ⚠ same residue
CDKN2A p.Ala86Thr Conflicting classifications of pathogenicity ★ ⚠ same residue
CDKN2A p.Ala86= Likely benign ★ same residue
CDKN2A c.150+2T>G Likely pathogenic ★★ same condition
CDKN2A c.151-1G>C Pathogenic ★★ same condition
CDKN2A c.151-1G>T Pathogenic/Likely pathogenic ★★ same condition
CDKN2A c.151-2A>G Pathogenic/Likely pathogenic ★★ same condition
CDKN2A c.193+2T>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/cdkn2a-p-ala86ser (accessed [today's date]).

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