Is NBAS p.Ile1230= (c.3690C>T) pathogenic?

NBAS p.Ile1230= (c.3690C>T) is classified Likely benign in NBAS (ClinVar, Multiple submitters, 2 submitters; last evaluated 2025-12-14). Very rare (popmax 0.0011%, nfe).

How common is NBAS p.Ile1230= (c.3690C>T) in the general population?

NBAS p.Ile1230= (c.3690C>T) is very rare (popmax 0.0011%, nfe) (gnomAD).

NBAS p.Ile1230=

c.3690C>T · rs1380995923 · VCV1946146

Likely benign Multiple submitters

Classification

Likely benign

ClinVar

Review

Multiple submitters ★★☆☆

ClinVar · 2 submitters

gnomAD v4.1

Rare

very rare (popmax 0.0011%, nfe)

Computational evidence

Protein change
Missense predictors do not apply to this variant type; conservation carries the signal.
REVEL	0.032	moderately benign-leaning
Splicing
SpliceAI	—	not assessed · no allele here is in the release
Constraint at this position
Conservation	phyloP 0.81	GERP -1.6, phastCons 1
Overall
CADD	7.705	PHRED · no single calibrated threshold — expert panels disagree

Population frequency

gnomAD v4.1 · exomes + genomes

Grpmax group 0.0011% European (non-Finnish) · 13/1,179,544 alleles

Filtering AF 0.000615% ClinGen BA1/BS1 input FAF95, joint · FAF99 0.000474%

Overall 0.000806% 13/1,613,430 alleles · very rare exomes 12/1,461,256 · genomes 1/152,174 · joint denominator

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.Ile1230=
Coding: c.3690C>T
MANE Select: NM_015909
dbSNP: rs1380995923
Type: single nucleotide variant
Location: chr2:15374621 (GRCh38)
Gene constraint: LOEUF 0.761 · pLI <0.01 · ClinGen HI gene assoc. with recessive phenotype (gnomAD)
Structure: AlphaFold pLDDT 74.42
Residue 1230: 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 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
NBAS c.513+2T>C Pathogenic/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-ile1230 (accessed [today's date]).

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