Is PRRT2 p.Asp226Val (c.677A>T) pathogenic?

PRRT2 p.Asp226Val (c.677A>T) is classified Uncertain significance in PRRT2 (ClinVar, Single submitter, 1 submitter; last evaluated 2024-04-16). AlphaMissense: ambiguous (0.4018); Absent from gnomAD v4.1; Associated with episodic kinesigenic dyskinesia.

What condition is associated with PRRT2 p.Asp226Val (c.677A>T)?

PRRT2 p.Asp226Val (c.677A>T) is associated with episodic kinesigenic dyskinesia (ClinVar).

How common is PRRT2 p.Asp226Val (c.677A>T) in the general population?

PRRT2 p.Asp226Val (c.677A>T) is absent from gnomAD v4.1 (gnomAD).

How is Paroxysmal kinesigenic dyskinesia inherited?

Typically Autosomal dominant, Not applicable (Orphanet). A genetic counselor can assess individual risk for a family.

What do computational predictors say about PRRT2 p.Asp226Val (c.677A>T)?

AlphaMissense predicts ambiguous (score 0.4018) — an in-silico prediction, not a clinical call.

PRRT2 p.Asp226Val

c.677A>T · VCV3637379

Uncertain significance Single submitter

Classification

Uncertain significance

ClinVar

Review

Single submitter ★☆☆☆

ClinVar · 1 submitter

AlphaMissense

ambiguous

0.4018 · ACMG-weighted

gnomAD v4.1

Absent

absent from gnomAD v4.1

Missense predictors

0/2 damaging

REVEL, SaProt · AlphaMissense indeterminate

Conditions

episodic kinesigenic dyskinesia

⚠ Built without this gene's context — gene constraint and dosage, protein structure, pathways, panels and related-variant links were not looked up for this page. why

Computational evidence

Protein change
AlphaMissense	0.4018	ambiguous
REVEL	0.235	benign-leaning
SaProt	LLR -6.91	tolerated
⇒ REVEL and SaProt both call this tolerated; AlphaMissense is indeterminate.
Splicing
SpliceAI	—	not looked up on this page · why
Constraint at this position
Conservation	phyloP 11	GERP 1.2, phastCons 1
Regional constraint	o/e 1.16	unconstrained · MANE · 785 bp · p 0.003 · regional, not allelic
Overall
CADD	24.0	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: PRRT2
Protein: p.Asp226Val
Coding: c.677A>T
MANE Select: NM_145239
Type: single nucleotide variant
Location: chr16:29813731 (GRCh38)

Full PRRT2 gene report on Sugi Atlas → Gene function, pathways, protein structure, interactions & more

Disease context

episodic kinesigenic dyskinesia — disease report on Sugi Atlas → Associated genes, phenotypes, clinical trials & treatments

For Paroxysmal kinesigenic dyskinesia (Orphanet):

Inheritance: Autosomal dominant, Not applicable
Onset: Adolescent, Adult, Childhood, Infancy
Prevalence: 1-9 / 1 000 000 (Worldwide)

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/prrt2-p-asp226val (accessed [today's date]).

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