Is CYBA p.Ile26= (c.78C>T) pathogenic?

CYBA p.Ile26= (c.78C>T) is classified Likely benign in CYBA (ClinVar, Multiple submitters, 2 submitters; last evaluated 2023-11-21). Ultra-rare (popmax 0.02%, amr); Associated with granulomatous disease, chronic, autosomal recessive, cytochrome b-negative.

How common is CYBA p.Ile26= (c.78C>T) in the general population?

CYBA p.Ile26= (c.78C>T) is ultra-rare (popmax 0.02%, amr) (gnomAD).

How is Chronic granulomatous disease inherited?

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

CYBA p.Ile26=

Q: What condition is associated with CYBA p.Ile26= (c.78C>T)?

CYBA p.Ile26= (c.78C>T) is associated with granulomatous disease, chronic, autosomal recessive, cytochrome b-negative (ClinVar).

c.78C>T · rs759139349 · VCV1607441

Likely benign Multiple submitters

Classification

Likely benign

ClinVar

Review

Multiple submitters ★★☆☆

ClinVar · 2 submitters

gnomAD v4.1

Rare

ultra-rare (popmax 0.02%, amr)

Conditions

granulomatous disease, chronic, autosomal recessive, cytochrome b-negative

Computational evidence

Protein change
Missense predictors do not apply to this variant type; conservation carries the signal.
Splicing
SpliceAI	<0.2	all four deltas below 0.2 · G>T here scores Δ0.20 · evaluated, not missing
Constraint at this position
Conservation	phyloP -1.8	GERP -2.5
Overall
CADD	4.879	PHRED · no single calibrated threshold — expert panels disagree

Population frequency

gnomAD v4.1 · exomes + genomes

Grpmax group 0.02% Admixed American · 12/59,922 alleles

Filtering AF 0.0115% ClinGen BA1/BS1 input FAF95, joint · FAF99 0.00899%

Overall 0.0011% 16/1,460,318 alleles · ultra-rare

Ancestry group	Frequency	1 in
Admixed Americangrpmax	0.02%	4,994
African / African-American	0.00133%	75,048
European (non-Finnish)	0.000254%	393,253

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: CYBA
Protein: p.Ile26=
Coding: c.78C>T
MANE Select: NM_000101
dbSNP: rs759139349
Type: single nucleotide variant
Location: chr16:88648095 (GRCh38)
Gene constraint: LOEUF 1.726 · pLI <0.01 (gnomAD)
Structure: AlphaFold pLDDT 77.28 · 7 PDB
Residue 26: an α-helix

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

Disease context

granulomatous disease, chronic, autosomal recessive, cytochrome b-negative — disease report on Sugi Atlas → Associated genes, phenotypes, clinical trials & treatments

For Chronic granulomatous disease (Orphanet):

Inheritance: Autosomal recessive, X-linked recessive
Onset: Adolescent, Adult, Childhood, Infancy
Prevalence: 1-9 / 1 000 000 (Worldwide)

Similar variants

CYBA p.Ile26fs Pathogenic/Likely pathogenic ★★ same residue
CYBA c.128+2T>C Likely pathogenic ★★ same condition
CYBA c.204-2A>G Pathogenic/Likely pathogenic ★★ same condition
CYBA c.287+1G>T Pathogenic/Likely pathogenic ★★ same condition
CYBA c.287+2T>C Pathogenic/Likely pathogenic ★★ same condition
CYBA c.288-1G>T Pathogenic/Likely pathogenic ★★ same condition
CYBA c.369+1G>A Likely pathogenic ★★ same condition
CYBA c.58+2T>C 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/cyba-p-ile26 (accessed [today's date]).

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