Is BBS2 p.Arg339Ter (c.1015C>T) pathogenic?

BBS2 p.Arg339Ter (c.1015C>T) is classified Pathogenic in BBS2 (ClinVar, Multiple submitters, 9 submitters; last evaluated 2025-10-05). Very rare (popmax 0.000339%, nfe); Associated with retinitis pigmentosa 74.

What condition is associated with BBS2 p.Arg339Ter (c.1015C>T)?

BBS2 p.Arg339Ter (c.1015C>T) is associated with retinitis pigmentosa 74, Bardet-Biedl syndrome 2, Bardet-Biedl syndrome (ClinVar).

How common is BBS2 p.Arg339Ter (c.1015C>T) in the general population?

BBS2 p.Arg339Ter (c.1015C>T) is very rare (popmax 0.000339%, nfe) (gnomAD).

How is Retinitis pigmentosa inherited?

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

BBS2 p.Arg339Ter

c.1015C>T · rs193922710 · VCV35754

Pathogenic Multiple submitters

Classification

Pathogenic

ClinVar

Review

Multiple submitters ★★☆☆

ClinVar · 9 submitters

Consequence

nonsense (stop-gain)

predicted LoF

gnomAD v4.1

Rare

very rare (popmax 0.000339%, nfe)

Conditions

retinitis pigmentosa 74

Computational evidence

Protein change
Missense predictors do not apply to this variant type; conservation carries the signal.
Consequence	nonsense (stop-gain)	predicted loss-of-function
NMD	predicted	premature termination codon in exon 9 of 17
Splicing
SpliceAI	—	not assessed · no allele here is in the release
Constraint at this position
Conservation	phyloP 7.4	GERP 2, phastCons 1
Overall
CADD	39.0	PHRED · no single calibrated threshold — expert panels disagree

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

Population frequency

gnomAD v4.1 · exomes + genomes

Grpmax group 0.000339% European (non-Finnish) · 4/1,180,040 alleles

Filtering AF 7.9e-05% ClinGen BA1/BS1 input FAF95, joint · FAF99 5.4e-05%

Overall 0.000274% 4/1,461,892 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: BBS2
Protein: p.Arg339Ter
Coding: c.1015C>T
MANE Select: NM_031885
dbSNP: rs193922710
Type: single nucleotide variant
Location: chr16:56502382 (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

retinitis pigmentosa 74 — disease report on Sugi Atlas → Associated genes, phenotypes, clinical trials & treatments

Also linked: Bardet-Biedl syndrome 2 Bardet-Biedl syndrome

For Retinitis pigmentosa (Orphanet):

Inheritance: Autosomal dominant, Autosomal recessive, Mitochondrial inheritance
Onset: Adolescent, Adult, Childhood
Prevalence: 1-5 / 10 000 (Europe)

Similar variants

BBS2 p.Arg339fs Pathogenic/Likely pathogenic ★★ same residue
BBS2 c.118-1G>T Likely pathogenic ★★ same condition
BBS2 c.118-2A>C Likely pathogenic ★★ same condition
BBS2 c.118-2A>G Likely pathogenic ★★ same condition
BBS2 c.1225+2T>C Likely pathogenic ★★ same condition
BBS2 c.1225+2T>G Likely pathogenic ★★ same condition
BBS2 c.1397+1G>A Pathogenic/Likely pathogenic ★★ same condition
BBS2 c.1397+2T>C 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-arg339ter (accessed [today's date]).

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