Is CFB p.Tyr309= (c.927T>C) pathogenic?

CFB p.Tyr309= (c.927T>C) is classified Likely benign in CFB (ClinVar, Single submitter, 1 submitter; last evaluated 2021-10-19). Very rare (popmax 0.000678%, nfe).

How common is CFB p.Tyr309= (c.927T>C) in the general population?

CFB p.Tyr309= (c.927T>C) is very rare (popmax 0.000678%, nfe) (gnomAD).

CFB p.Tyr309=

c.927T>C · rs1042138271 · VCV1594759

Likely benign Single submitter

Classification

Likely benign

ClinVar

Review

Single submitter ★☆☆☆

ClinVar · 1 submitter

gnomAD v4.1

Rare

very rare (popmax 0.000678%, nfe)

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 · T>G here scores Δ0.25 · evaluated, not missing
Constraint at this position
Conservation	phyloP -4	GERP -3.9
Overall
CADD	0.519	PHRED · no single calibrated threshold — expert panels disagree

Population frequency

gnomAD v4.1 · exomes + genomes

Grpmax group 0.000678% European (non-Finnish) · 8/1,180,038 alleles

Filtering AF 0.000292% ClinGen BA1/BS1 input FAF95, joint · FAF99 0.000211%

Overall 0.000496% 8/1,614,198 alleles · very rare exomes 8/1,461,894 · genomes 0/152,304 · joint denominator

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: CFB
Protein: p.Tyr309=
Coding: c.927T>C
MANE Select: NM_001710
dbSNP: rs1042138271
Type: single nucleotide variant
Location: chr6:31948403 (GRCh38)
Gene constraint: LOEUF 0.719 · pLI <0.01 (gnomAD)
Structure: AlphaFold pLDDT 86.54 · 28 PDB
Residue 309: a β-strand; the vwfa domain

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

Similar variants

CFB c.2140-1G>C Uncertain significance ★★ same type
CFB c.-3G>A Uncertain significance ★★ same type
CFB p.Ala162Val Uncertain significance ★★ ⚠ same type
CFB p.Ala289Val Uncertain significance ★★ same type
CFB p.Ala567Gly Uncertain significance ★★ ⚠ same type
CFB p.Arg117Trp Uncertain significance ★★ ⚠ same type
CFB p.Arg138Gln Uncertain significance ★★ ⚠ same type
CFB p.Arg138Trp Uncertain significance ★★ ⚠ same type

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/cfb-p-tyr309 (accessed [today's date]).

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