Is CLPB p.Glu221= (c.663G>A) pathogenic?

CLPB p.Glu221= (c.663G>A) is classified Likely benign in CLPB (ClinVar, Multiple submitters, 3 submitters; last evaluated 2025-11-24). Ultra-rare (popmax 0.0956%, sas); Associated with 3-methylglutaconic aciduria, type VIIB.

What condition is associated with CLPB p.Glu221= (c.663G>A)?

CLPB p.Glu221= (c.663G>A) is associated with 3-methylglutaconic aciduria, type VIIB (ClinVar).

How common is CLPB p.Glu221= (c.663G>A) in the general population?

CLPB p.Glu221= (c.663G>A) is ultra-rare (popmax 0.0956%, sas) (gnomAD).

CLPB p.Glu221=

Q: How is 3-methylglutaconic aciduria-neonatal cataract-neurologic involvement-congenital neutropenia syndrome inherited?

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

c.663G>A · rs571326442 · VCV742714

Likely benign Multiple submitters

Classification

Likely benign

ClinVar

Review

Multiple submitters ★★☆☆

ClinVar · 3 submitters

gnomAD v4.1

Rare

ultra-rare (popmax 0.0956%, sas)

Conditions

3-methylglutaconic aciduria, type VIIB

Computational evidence

Protein change
Missense predictors do not apply to this variant type; conservation carries the signal.
REVEL	0.06	moderately benign-leaning
Splicing
SpliceAI	—	not assessed · no allele here is in the release
Constraint at this position
Conservation	phyloP -0.22	GERP -2, phastCons 0.24
Overall
CADD	7.181	PHRED · no single calibrated threshold — expert panels disagree

Population frequency

gnomAD v4.1 · exomes + genomes

Grpmax group 0.0956% South Asian · 87/91,040 alleles

Filtering AF 0.0793% ClinGen BA1/BS1 input FAF95, joint · FAF99 0.0733%

Overall 0.00564% 91/1,613,618 alleles · ultra-rare

Ancestry group	Frequency	1 in
South Asiangrpmax	0.0956%	1,046
Remaining individualsnot grpmax-eligible	0.0048%	20,831
African / African-American	0.00134%	74,870

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: CLPB
Protein: p.Glu221=
Coding: c.663G>A
MANE Select: NM_001258392
dbSNP: rs571326442
Type: single nucleotide variant
Location: chr11:72358992 (GRCh38)
Gene constraint: LOEUF 0.643 · pLI <0.01 (gnomAD)
Structure: AlphaFold pLDDT 72.52 · 7 PDB

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

Disease context

3-methylglutaconic aciduria, type VIIB — disease report on Sugi Atlas → Associated genes, phenotypes, clinical trials & treatments

For 3-methylglutaconic aciduria-neonatal cataract-neurologic involvement-congenital neutropenia syndrome (Orphanet):

Inheritance: Autosomal recessive
Onset: Antenatal, Neonatal

Similar variants

CLPB p.Gly221Ser Benign/Likely benign ★★ same residue
CLPB c.1066+1G>A Pathogenic/Likely pathogenic ★★ same condition
CLPB c.455+1G>A Likely pathogenic ★★ same condition
CLPB c.873+1G>A Pathogenic/Likely pathogenic ★★ same condition
CLPB c.874-2A>G Likely pathogenic ★★ same condition
CLPB p.Arg178Ter Pathogenic ★★ same condition
CLPB p.Arg312Ter Pathogenic/Likely pathogenic ★★ same condition
CLPB p.Arg378Gly 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/clpb-p-glu221 (accessed [today's date]).

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