Is ASPA p.Lys300Arg (c.899A>G) pathogenic?

ASPA p.Lys300Arg (c.899A>G) is classified Uncertain significance in ASPA (ClinVar, Single submitter, 1 submitter; last evaluated 2022-09-12). AlphaMissense: likely benign (0.0772); Very rare (popmax 0.000169%, nfe); Associated with Canavan disease.

What condition is associated with ASPA p.Lys300Arg (c.899A>G)?

ASPA p.Lys300Arg (c.899A>G) is associated with Canavan disease (ClinVar).

How common is ASPA p.Lys300Arg (c.899A>G) in the general population?

ASPA p.Lys300Arg (c.899A>G) is very rare (popmax 0.000169%, nfe) (gnomAD).

How is Canavan disease inherited?

Typically Autosomal recessive (Orphanet). A genetic counselor can assess individual risk for a family.

What do computational predictors say about ASPA p.Lys300Arg (c.899A>G)?

AlphaMissense predicts likely benign (score 0.0772) — an in-silico prediction, not a clinical call.

ASPA p.Lys300Arg

c.899A>G · rs890496947 · VCV2150556

Uncertain significance Single submitter

Classification

Uncertain significance

ClinVar

Review

Single submitter ★☆☆☆

ClinVar · 1 submitter

AlphaMissense

likely benign

0.0772 · ACMG-weighted

gnomAD v4.1

Rare

very rare (popmax 0.000169%, nfe)

Missense predictors

0/2 damaging

AlphaMissense, SaProt · REVEL no call

Conditions

Canavan disease

Computational evidence

Protein change
AlphaMissense	0.0772	likely benign
REVEL	0.383	indeterminate
SaProt	LLR -7.85	tolerated
⇒ AlphaMissense and SaProt both call this tolerated; REVEL makes no call.
Splicing
SpliceAI	—	not assessed · no allele here is in the release
Constraint at this position
Conservation	phyloP 7.8	GERP -0.59, phastCons 1
Regional constraint	o/e 0.86	unconstrained · MANE · 23 kb · p 0.0073 · regional, not allelic
Overall
CADD	17.61	PHRED · no single calibrated threshold — expert panels disagree

ClinVar classifies this uncertain; the computational predictors unanimously lean tolerated — a triage signal, not a reclassification

AlphaMissense carries the ACMG weight for missense; REVEL and SaProt are independent agreement signals.

Population frequency

gnomAD v4.1 · exomes + genomes

Grpmax group 0.000169% European (non-Finnish) · 2/1,180,040 alleles

Filtering AF 2.8e-05% ClinGen BA1/BS1 input FAF95, joint · FAF99 1.1e-05%

Overall 0.000124% 2/1,614,038 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: ASPA
Protein: p.Lys300Arg
Coding: c.899A>G
MANE Select: NM_000049
dbSNP: rs890496947
Type: single nucleotide variant
Location: chr17:3499045 (GRCh38)
Gene constraint: LOEUF 1.098 · pLI <0.01 · ClinGen HI gene assoc. with recessive phenotype (gnomAD)
Structure: AlphaFold pLDDT 96.14 · 8 PDB
Residue 300: a β-strand

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

Disease context

Canavan disease — disease report on Sugi Atlas → Associated genes, phenotypes, clinical trials & treatments

For Canavan disease (Orphanet):

Inheritance: Autosomal recessive
Onset: Childhood, Infancy, Neonatal

Similar variants

ASPA p.Lys300Gln Uncertain significance ★ ⚠ same residue
ASPA c.236+2T>C Likely pathogenic ★★ same condition
ASPA c.237-1G>T Likely pathogenic ★★ same condition
ASPA c.237-2A>T Pathogenic/Likely pathogenic ★★ same condition
ASPA c.527-1G>A Likely pathogenic ★★ same condition
ASPA c.527-2A>C Likely pathogenic ★★ same condition
ASPA c.527-2A>G Likely pathogenic ★★ same condition
ASPA c.634+1G>T Pathogenic/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/aspa-p-lys300arg (accessed [today's date]).

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