Is LDLR p.Cys255Ser (c.763T>A) pathogenic?

LDLR p.Cys255Ser (c.763T>A) is classified Likely pathogenic in LDLR (ClinVar, Multiple submitters, 3 submitters; last evaluated 2023-10-02). AlphaMissense: likely pathogenic (0.9973); Absent from gnomAD v4.1; Associated with hypercholesterolemia, familial, 1.

What condition is associated with LDLR p.Cys255Ser (c.763T>A)?

LDLR p.Cys255Ser (c.763T>A) is associated with hypercholesterolemia, familial, 1 (ClinVar).

How common is LDLR p.Cys255Ser (c.763T>A) in the general population?

LDLR p.Cys255Ser (c.763T>A) is absent from gnomAD v4.1 (gnomAD).

What do computational predictors say about LDLR p.Cys255Ser (c.763T>A)?

AlphaMissense predicts likely pathogenic (score 0.9973) — an in-silico prediction, not a clinical call.

LDLR p.Cys255Ser

c.763T>A · rs879254668 · VCV251440

Likely pathogenic Multiple submitters

Classification

Likely pathogenic

ClinVar

Review

Multiple submitters ★★☆☆

ClinVar · 3 submitters

AlphaMissense

likely pathogenic

0.9973 · ACMG-weighted

gnomAD v4.1

Absent

absent from gnomAD v4.1

Missense predictors

3/3 damaging

AlphaMissense, REVEL, SaProt

Conditions

hypercholesterolemia, familial, 1

Computational evidence

Protein change
AlphaMissense	0.9973	likely pathogenic ✓ concordant with ClinVar · top 1% in LDLR
REVEL	0.957	strongly pathogenic-leaning
SaProt	LLR -15.78	damaging
⇒ AlphaMissense, REVEL and SaProt all call this damaging.
Splicing
SpliceAI	—	not assessed · no allele here is in the release
Constraint at this position
Conservation	phyloP 7.8	GERP 1.9, phastCons 1
Regional constraint	o/e 1.00	unconstrained · MANE · 42 kb · p 0.91 · regional, not allelic
Overall
CADD	26.5	PHRED · no single calibrated threshold — expert panels disagree

AlphaMissense carries the ACMG weight for missense; REVEL and SaProt are independent agreement signals.

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: LDLR
Protein: p.Cys255Ser
Coding: c.763T>A
MANE Select: NM_000527
dbSNP: rs879254668
Type: single nucleotide variant
Location: chr19:11106633 (GRCh38)
Gene constraint: LOEUF 1.091 · pLI <0.01 · ClinGen HI 3/3 (gnomAD)
Structure: AlphaFold pLDDT 75.81 · 36 PDB
Residue 255: the ldl-receptor class a 6 domain; a UniProt-annotated variant site (in fhcl1); a β-strand; a disulfide bond

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

Disease context

hypercholesterolemia, familial, 1 — disease report on Sugi Atlas → Associated genes, phenotypes, clinical trials & treatments

Similar variants

LDLR p.Cys255Tyr Likely pathogenic ★ same residue
LDLR p.Cys255Gly Conflicting classifications of pathogenicity ★ ⚠ same residue
LDLR p.Cys255Phe Pathogenic same residue
LDLR p.Cys255Arg Likely pathogenic ★ same residue
LDLR c.1186+5G>A Likely pathogenic ★★★ same condition
LDLR c.1359-1G>A Pathogenic ★★★ same condition
LDLR c.1359-5C>G Likely pathogenic ★★★ same condition
LDLR c.1705+2T>C 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/ldlr-p-cys255ser (accessed [today's date]).

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