Is GBA2 p.Trp166Arg (c.496T>C) pathogenic?

GBA2 p.Trp166Arg (c.496T>C) is classified Uncertain significance in GBA2 (ClinVar, Single submitter, 1 submitter; last evaluated 2022-04-11). AlphaMissense: likely pathogenic (0.9756); Very rare (popmax 0.00267%, afr); Associated with Spastic paraplegia.

What condition is associated with GBA2 p.Trp166Arg (c.496T>C)?

GBA2 p.Trp166Arg (c.496T>C) is associated with Spastic paraplegia (ClinVar).

How common is GBA2 p.Trp166Arg (c.496T>C) in the general population?

GBA2 p.Trp166Arg (c.496T>C) is very rare (popmax 0.00267%, afr) (gnomAD).

What do computational predictors say about GBA2 p.Trp166Arg (c.496T>C)?

AlphaMissense predicts likely pathogenic (score 0.9756) — an in-silico prediction, not a clinical call.

GBA2 p.Trp166Arg

c.496T>C · rs980564749 · VCV2150017

Uncertain significance Single submitter

Classification

Uncertain significance

ClinVar

Review

Single submitter ★☆☆☆

ClinVar · 1 submitter

AlphaMissense

likely pathogenic

0.9756 · ACMG-weighted

gnomAD v4.1

Rare

very rare (popmax 0.00267%, afr)

Missense predictors

1/3 damaging

AlphaMissense, REVEL, SaProt

Conditions

Spastic paraplegia

Computational evidence

Protein change
AlphaMissense	0.9756	likely pathogenic · top 6% in GBA2
REVEL	0.29	benign-leaning
SaProt	LLR -6.87	tolerated
⇒ AlphaMissense calls this damaging; REVEL and SaProt do not.
Splicing
SpliceAI	—	not assessed · no allele here is in the release
Constraint at this position
Conservation	phyloP 9.4	GERP 0.7, phastCons 1
Regional constraint	o/e 0.88	unconstrained · MANE · 12 kb · p 2e-05 · 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 0.00267% African / African-American · 2/74,896 alleles

Filtering AF 0.000764% ClinGen BA1/BS1 input FAF95, joint · FAF99 0.000606%

Overall 0.00112% 18/1,613,254 alleles · very rare

Ancestry group	Frequency	1 in
African / African-Americangrpmax	0.00267%	37,448
Remaining individualsnot grpmax-eligible	0.0016%	62,464
European (non-Finnish)	0.00127%	78,621

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: GBA2
Protein: p.Trp166Arg
Coding: c.496T>C
MANE Select: NM_020944
dbSNP: rs980564749
Type: single nucleotide variant
Location: chr9:35744368 (GRCh38)
Gene constraint: LOEUF 0.773 · pLI <0.01 · ClinGen HI gene assoc. with recessive phenotype (gnomAD)
Structure: AlphaFold pLDDT 89.77
Residue 166: a UniProt-annotated variant site (in spg46; loss of glucosylceramide catabolic process)

Full GBA2 gene report on Sugi Atlas → Gene function, pathways, protein structure, interactions & more

Disease context

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

Similar variants

GBA2 p.Arg234Ter Pathogenic ★★ same condition
GBA2 p.Arg340Ter Pathogenic ★★ same condition
GBA2 p.Arg574Ter Pathogenic ★★ same condition
GBA2 p.Ala187Thr Uncertain significance ★★ ⚠ same condition
GBA2 p.Arg215His Uncertain significance ★★ ⚠ same condition
GBA2 p.Arg514Cys Uncertain significance ★★ ⚠ same condition
GBA2 p.Arg575Gln Uncertain significance ★★ ⚠ same condition
GBA2 p.Arg575Trp Uncertain significance ★★ ⚠ 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/gba2-p-trp166arg (accessed [today's date]).

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