Is CFB p.Ser687fs (c.2058_2061del) pathogenic?

CFB p.Ser687fs (c.20582061del) is classified Uncertain significance in CFB (ClinVar, Single submitter, 1 submitter; last evaluated 2025-09-26). Very rare (popmax 0.000254%, nfe); Associated with atypical hemolytic-uremic syndrome.

What condition is associated with CFB p.Ser687fs (c.2058_2061del)?

CFB p.Ser687fs (c.2058_2061del) is associated with atypical hemolytic-uremic syndrome (ClinVar).

How common is CFB p.Ser687fs (c.2058_2061del) in the general population?

CFB p.Ser687fs (c.2058_2061del) is very rare (popmax 0.000254%, nfe) (gnomAD).

How is Atypical hemolytic uremic syndrome inherited?

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

CFB p.Ser687fs

c.2058_2061del · VCV4280386

Uncertain significance Single submitter

Classification

Uncertain significance

ClinVar

Review

Single submitter ★☆☆☆

ClinVar · 1 submitter

Consequence

frameshift

predicted LoF

gnomAD v4.1

Rare

very rare (popmax 0.000254%, nfe)

Conditions

atypical hemolytic-uremic syndrome

Computational evidence

Protein change
Missense predictors do not apply to this variant type; conservation carries the signal.
Consequence	frameshift	predicted loss-of-function; NMD-escape possible for C-terminal truncations
Splicing
SpliceAI	—	not assessed · substitutions only
Constraint at this position
Conservation	phyloP 12	GERP 1.7, phastCons 1

Predicted loss-of-function is descriptive, not an applied PVS1 code.

Population frequency

gnomAD v4.1 · exomes + genomes

Grpmax group 0.000254% European (non-Finnish) · 3/1,180,026 alleles

Filtering AF 6.8e-05% ClinGen BA1/BS1 input FAF95, joint · FAF99 1.9e-05%

Overall 0.000205% 3/1,461,894 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: CFB
Protein: p.Ser687fs
Coding: c.2058_2061del
MANE Select: NM_001710
Type: Microsatellite
Location: chr6:31951438 (GRCh38)
Gene constraint: LOEUF 0.719 · pLI <0.01 (gnomAD)
Structure: AlphaFold pLDDT 86.54 · 28 PDB
Residue 687: a β-strand; the peptidase s1 domain

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

Disease context

atypical hemolytic-uremic syndrome — disease report on Sugi Atlas → Associated genes, phenotypes, clinical trials & treatments

For Atypical hemolytic uremic syndrome (Orphanet):

Inheritance: Autosomal dominant, Autosomal recessive, Not applicable
Onset: All ages
Prevalence: 1-9 / 1 000 000 (United States)

Similar variants

CFB p.Arg138Gln Uncertain significance ★★ ⚠ same condition
CFB p.Arg138Trp Uncertain significance ★★ ⚠ same condition
CFB p.Arg203Gln Uncertain significance ★★ ⚠ same condition
CFB p.Arg379Cys Uncertain significance ★★ ⚠ same condition
CFB p.Gln256Ter Uncertain significance ★★ same condition
CFB p.Glu601Lys Uncertain significance ★★ ⚠ same condition
CFB p.Ser284Asn Uncertain significance ★★ ⚠ same condition
CFB c.1036+111A>G Benign ★★ 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/cfb-p-ser687fs (accessed [today's date]).

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