Is ABO p.Ile256= (c.768C>T) pathogenic?

ABO p.Ile256= (c.768C>T) is classified Likely benign in ABO (ClinVar, Single submitter, 1 submitter; last evaluated 2020-12-17). No allele count reported in gnomAD v4.1 (AN 1,603,030); Associated with ABO-related disorder.

What condition is associated with ABO p.Ile256= (c.768C>T)?

ABO p.Ile256= (c.768C>T) is associated with ABO-related disorder (ClinVar).

How common is ABO p.Ile256= (c.768C>T) in the general population?

ABO p.Ile256= (c.768C>T) is no allele count reported in gnomAD v4.1 (AN 1,603,030) (gnomAD).

ABO p.Ile256=

c.768C>T · rs8176744 · VCV3035005

Likely benign Single submitter

Classification

Likely benign

ClinVar

Review

Single submitter ★☆☆☆

ClinVar · 1 submitter

gnomAD v4.1

Not reported

no allele count reported in gnomAD v4.1 (AN 1,603,030)

Conditions

ABO-related disorder

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 -2.4	GERP -2.8
Overall
CADD	1.85	PHRED · no single calibrated threshold — expert panels disagree

Population frequency

gnomAD v4.1 · exomes + genomes

No allele count reported in gnomAD v4.1 (AN 1,603,030). This is missing data, not an absence: the variant may or may not be present in gnomAD. Rarity (ACMG PM2) and BA1/BS1 cannot be assessed for it.

Variant & gene context

Gene: ABO
Protein: p.Ile256=
Coding: c.768C>T
dbSNP: rs8176744
Type: single nucleotide variant
Location: chr9:133255963 (GRCh38)
Gene constraint: LOEUF 1.416 · pLI <0.01 (gnomAD)
Structure: AlphaFold pLDDT 89.59 · 151 PDB

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

Disease context

ABO-related disorder

Similar variants

ABO p.Glu276Lys Likely benign ★ same condition
ABO p.Leu324= Benign ★ same condition
ABO p.Cys14Ter Benign same condition
ABO p.Tyr34Ter Benign same condition
ABO p.Ala177Thr Likely benign ★ same type
ABO p.Gly268Ala Benign ★ same type
ABO p.Phe216Ile Benign ★ same type
ABO p.Pro74Ser Benign ★ 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/abo-p-ile256 (accessed [today's date]).

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