Is NBAS p.Arg2263Ter (c.6787C>T) pathogenic?

NBAS p.Arg2263Ter (c.6787C>T) is classified Pathogenic in NBAS (ClinVar, Single submitter, 1 submitter; last evaluated 2025-01-07). Very rare (popmax 0.00549%, sas).

How common is NBAS p.Arg2263Ter (c.6787C>T) in the general population?

NBAS p.Arg2263Ter (c.6787C>T) is very rare (popmax 0.00549%, sas) (gnomAD).

NBAS p.Arg2263Ter

c.6787C>T · rs746756510 · VCV1943337

Pathogenic Single submitter

Classification

Pathogenic

ClinVar

Review

Single submitter ★☆☆☆

ClinVar · 1 submitter

Consequence

nonsense (stop-gain)

predicted LoF

gnomAD v4.1

Rare

very rare (popmax 0.00549%, sas)

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 51 of 52
Splicing
SpliceAI	—	not assessed · no allele here is in the release
Constraint at this position
Conservation	phyloP 2.7	GERP 0.29, 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

Grpmax group 0.00549% South Asian · 5/91,080 alleles

Filtering AF 0.0021% ClinGen BA1/BS1 input FAF95, joint · FAF99 0.00136%

Overall 0.000496% 8/1,613,942 alleles · very rare

Ancestry group	Frequency	1 in
South Asiangrpmax	0.00549%	18,216
European (non-Finnish)	0.000254%	393,337

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: NBAS
Protein: p.Arg2263Ter
Coding: c.6787C>T
MANE Select: NM_015909
dbSNP: rs746756510
Type: single nucleotide variant
Location: chr2:15179041 (GRCh38)
Gene constraint: LOEUF 0.761 · pLI <0.01 · ClinGen HI gene assoc. with recessive phenotype (gnomAD)
Structure: AlphaFold pLDDT 74.42
Residue 2263: a UniProt-annotated variant site (in ilfs2; uncertain significance); a UniProt-annotated variant site (found in a patient with a multisystem disease involving liver, eye, immune system, connective tissue and bone; uncertain significance); a UniProt-annotated variant site (found in a patient with a multisystem disease involving liver, eye, immune system, connective tissue and bone; uncertain significance; reduced protein expression levels in fibroblasts); a UniProt-annotated variant site (found in a patient with a multisystem disease involving liver, eye, immune system, connective tissue and bone; uncertain significance; reduced collagen secretion; diffuse collagen bundles; reduced protein expression in fibroblasts); the 'interaction with zw10 and rint1' region

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

Similar variants

NBAS p.Arg2263Gln Likely benign ★ same residue
NBAS c.1726-2A>G Likely pathogenic ★★ same type
NBAS c.173-2A>G Likely pathogenic ★★ same type
NBAS c.209+2T>G Pathogenic/Likely pathogenic ★★ same type
NBAS c.2423+404G>C Likely pathogenic ★★ same type
NBAS c.335+1G>C Pathogenic/Likely pathogenic ★★ same type
NBAS c.4461+2T>C Likely pathogenic ★★ same type
NBAS c.4583-2A>G Likely pathogenic ★★ 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/nbas-p-arg2263ter (accessed [today's date]).

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