Is BBS2 p.Phe423fs (c.1269del) pathogenic?

BBS2 p.Phe423fs (c.1269del) is classified Likely pathogenic in BBS2 (ClinVar, Multiple submitters, 2 submitters; last evaluated 2024-06-21). Absent from gnomAD; Associated with Bardet-Biedl syndrome 2.

What condition is associated with BBS2 p.Phe423fs (c.1269del)?

BBS2 p.Phe423fs (c.1269del) is associated with Bardet-Biedl syndrome 2, retinitis pigmentosa 74 (ClinVar).

How common is BBS2 p.Phe423fs (c.1269del) in the general population?

BBS2 p.Phe423fs (c.1269del) is absent from gnomAD (gnomAD).

How is Bardet-Biedl syndrome inherited?

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

BBS2 p.Phe423fs

c.1269del · rs2543707834 · VCV3240884

Likely pathogenic Multiple submitters

Classification

Likely pathogenic

ClinVar

Review

Multiple submitters ★★☆☆

ClinVar · 2 submitters

Consequence

frameshift

predicted LoF

gnomAD v4.1

Not reported

no gnomAD frequency available for this variant

Conditions

Bardet-Biedl syndrome 2

Computational evidence

Protein change
Missense predictors do not apply to this variant type; conservation carries the signal.
Consequence	frameshift	predicted loss-of-function
NMD	predicted	premature termination codon in exon 11 of 17
Splicing
SpliceAI	—	not assessed · substitutions only
Constraint at this position
Conservation	phyloP -0.13	GERP -2.6

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

Population frequency

dbSNP / gnomAD

No gnomAD frequency available for this variant. This is missing data, not an absence: the variant may or may not be present in gnomAD. Rarity (ACMG PM2) and BA1/BS1 cannot be assessed for it.

Variant & gene context

Gene: BBS2
Protein: p.Phe423fs
Coding: c.1269del
MANE Select: NM_031885
dbSNP: rs2543707834
Type: Deletion
Location: chr16:56500982 (GRCh38)
Gene constraint: LOEUF 0.892 · pLI <0.01 (gnomAD)
Structure: AlphaFold pLDDT 89.49

Full BBS2 gene report on Sugi Atlas → Gene function, pathways, protein structure, interactions & more

Disease context

Bardet-Biedl syndrome 2 — disease report on Sugi Atlas → Associated genes, phenotypes, clinical trials & treatments

Also linked: retinitis pigmentosa 74

For Bardet-Biedl syndrome (Orphanet):

Inheritance: Autosomal recessive, Oligogenic
Onset: Antenatal, Childhood, Infancy, Neonatal
Prevalence: 1-9 / 100 000 (Specific population)

Similar variants

BBS2 p.Phe423Leu Uncertain significance ★ ⚠ same residue
BBS2 c.472del Pathogenic/Likely pathogenic ★★ same condition
BBS2 c.940+1del Pathogenic/Likely pathogenic ★★ same condition
BBS2 p.Arg339fs Pathogenic/Likely pathogenic ★★ same condition
BBS2 p.Asn258fs Pathogenic/Likely pathogenic ★★ same condition
BBS2 p.Asp371fs Likely pathogenic ★★ same condition
BBS2 p.Asp649fs Pathogenic/Likely pathogenic ★★ same condition
BBS2 p.Cys210fs 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/bbs2-p-phe423fs (accessed [today's date]).

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