Is CRB1 p.Asp226= (c.678C>T) pathogenic?

CRB1 p.Asp226= (c.678C>T) is classified Likely benign in CRB1 (ClinVar, Multiple submitters, 2 submitters; last evaluated 2025-12-23). Very rare (popmax 0.00769%, sas); Associated with retinitis pigmentosa 12.

What condition is associated with CRB1 p.Asp226= (c.678C>T)?

CRB1 p.Asp226= (c.678C>T) is associated with retinitis pigmentosa 12, Leber congenital amaurosis 8 (ClinVar).

How common is CRB1 p.Asp226= (c.678C>T) in the general population?

CRB1 p.Asp226= (c.678C>T) is very rare (popmax 0.00769%, sas) (gnomAD).

How is Retinitis pigmentosa inherited?

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

CRB1 p.Asp226=

c.678C>T · rs753324293 · VCV1161464

Likely benign Multiple submitters

Classification

Likely benign

ClinVar

Review

Multiple submitters ★★☆☆

ClinVar · 2 submitters

gnomAD v4.1

Rare

very rare (popmax 0.00769%, sas)

Conditions

retinitis pigmentosa 12

Computational evidence

Protein change
Missense predictors do not apply to this variant type; conservation carries the signal.
Splicing
SpliceAI	—	not assessed · no allele here is in the release
Constraint at this position
Conservation	phyloP -1.3	GERP -3.8
Overall
CADD	6.789	PHRED · no single calibrated threshold — expert panels disagree

Population frequency

gnomAD v4.1 · exomes + genomes

Grpmax group 0.00769% South Asian · 7/91,080 alleles

Filtering AF 0.00359% ClinGen BA1/BS1 input FAF95, joint · FAF99 0.00255%

Overall 0.00137% 20/1,461,856 alleles · very rare

Ancestry group	Frequency	1 in
South Asiangrpmax	0.00769%	13,011
European (non-Finnish)	0.0011%	90,770

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: CRB1
Protein: p.Asp226=
Coding: c.678C>T
MANE Select: NM_201253
dbSNP: rs753324293
Type: single nucleotide variant
Location: chr1:197344306 (GRCh38)
Gene constraint: LOEUF 0.776 · pLI <0.01 (gnomAD)
Structure: AlphaFold pLDDT 75.19 · 1 PDB
Residue 226: the egf-like 6; calcium-binding domain

Full CRB1 gene report on Sugi Atlas → Gene function, pathways, protein structure, interactions & more

Disease context

retinitis pigmentosa 12 — disease report on Sugi Atlas → Associated genes, phenotypes, clinical trials & treatments

Also linked: Leber congenital amaurosis 8

For Retinitis pigmentosa (Orphanet):

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

Similar variants

CRB1 p.Asp226Ala Uncertain significance ★★ ⚠ same residue
CRB1 c.1172-2A>G Likely pathogenic ★★ same condition
CRB1 c.2128+1G>C Pathogenic/Likely pathogenic ★★ same condition
CRB1 c.2129-1G>A Pathogenic/Likely pathogenic ★★ same condition
CRB1 c.2129-1G>C Pathogenic ★★ same condition
CRB1 c.2129-2A>G Pathogenic ★★ same condition
CRB1 c.2676+1G>A Likely pathogenic ★★ same condition
CRB1 c.2842+5G>A 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/crb1-p-asp226 (accessed [today's date]).

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