Is BBS7 p.Lys255Ter (c.763A>T) pathogenic?

BBS7 p.Lys255Ter (c.763A>T) is classified Pathogenic in BBS7 (ClinVar, Single submitter, 1 submitter; last evaluated 2018-10-01). Absent from gnomAD v4.1; Associated with Bardet-Biedl syndrome.

What condition is associated with BBS7 p.Lys255Ter (c.763A>T)?

BBS7 p.Lys255Ter (c.763A>T) is associated with Bardet-Biedl syndrome (ClinVar).

How common is BBS7 p.Lys255Ter (c.763A>T) in the general population?

BBS7 p.Lys255Ter (c.763A>T) is absent from gnomAD v4.1 (gnomAD).

How is Bardet-Biedl syndrome inherited?

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

BBS7 p.Lys255Ter

c.763A>T · rs1560658189 · VCV625451

Pathogenic Single submitter

Classification

Pathogenic

ClinVar

Review

Single submitter ★☆☆☆

ClinVar · 1 submitter

Consequence

nonsense (stop-gain)

predicted LoF

gnomAD v4.1

Absent

absent from gnomAD v4.1

Conditions

Bardet-Biedl syndrome

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 8 of 19
Splicing
SpliceAI	<0.2	all four deltas below 0.2 · T>C here scores Δ0.24 · evaluated, not missing
Constraint at this position
Conservation	phyloP 6.2	GERP 1.7, phastCons 1
Overall
CADD	37.0	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

Absent from gnomAD v4.1. Not observed in any sequenced alleles — a rarity signal (ACMG PM2-supporting), not evidence of pathogenicity on its own.

Variant & gene context

Gene: BBS7
Protein: p.Lys255Ter
Coding: c.763A>T
MANE Select: NM_176824
dbSNP: rs1560658189
Type: single nucleotide variant
Location: chr4:121853042 (GRCh38)
Gene constraint: LOEUF 0.701 · pLI <0.01 · ClinGen HI gene assoc. with recessive phenotype (gnomAD)
Structure: AlphaFold pLDDT 92.99

Full BBS7 gene report on Sugi Atlas → Gene function, pathways, protein structure, interactions & more

Disease context

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

For Bardet-Biedl syndrome (Orphanet):

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

Similar variants

BBS7 c.1305+2T>A Likely pathogenic ★★ same condition
BBS7 c.1371+1G>A Likely pathogenic ★★ same condition
BBS7 c.1512-1G>A Likely pathogenic ★★ same condition
BBS7 c.1677-2A>G Pathogenic/Likely pathogenic ★★ same condition
BBS7 c.1891-2A>C Pathogenic/Likely pathogenic ★★ same condition
BBS7 c.342-2A>G Pathogenic/Likely pathogenic ★★ same condition
BBS7 c.849+1G>C Pathogenic/Likely pathogenic ★★ same condition
BBS7 p.Arg280Ter 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/bbs7-p-lys255ter (accessed [today's date]).

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