Is COL1A2 p.Pro261Thr (c.781C>A) pathogenic?

COL1A2 p.Pro261Thr (c.781C>A) is classified Uncertain significance in COL1A2 (ClinVar, Multiple submitters, 3 submitters; last evaluated 2025-10-09). AlphaMissense: likely benign (0.0906); Very rare (popmax 0.000932%, nfe); Associated with osteogenesis imperfecta type 1.

What condition is associated with COL1A2 p.Pro261Thr (c.781C>A)?

COL1A2 p.Pro261Thr (c.781C>A) is associated with osteogenesis imperfecta type 1, Ehlers-Danlos syndrome, classic type, 1 (ClinVar).

How common is COL1A2 p.Pro261Thr (c.781C>A) in the general population?

COL1A2 p.Pro261Thr (c.781C>A) is very rare (popmax 0.000932%, nfe) (gnomAD).

What do computational predictors say about COL1A2 p.Pro261Thr (c.781C>A)?

AlphaMissense predicts likely benign (score 0.0906) — an in-silico prediction, not a clinical call.

COL1A2 p.Pro261Thr

c.781C>A · rs141075408 · VCV570914

Uncertain significance Multiple submitters

Classification

Uncertain significance

ClinVar

Review

Multiple submitters ★★☆☆

ClinVar · 3 submitters

AlphaMissense

likely benign

0.0906 · ACMG-weighted

gnomAD v4.1

Rare

very rare (popmax 0.000932%, nfe)

Missense predictors

0/2 damaging

AlphaMissense, SaProt · REVEL no call

Conditions

osteogenesis imperfecta type 1

Computational evidence

Protein change
AlphaMissense	0.0906	likely benign
REVEL	0.612	indeterminate
SaProt	LLR -7.95	tolerated
⇒ AlphaMissense and SaProt both call this tolerated; REVEL makes no call.
Splicing
SpliceAI	—	not assessed · no allele here is in the release
Constraint at this position
Conservation	phyloP 4.1	GERP 2.2, phastCons 1
Regional constraint	o/e 0.71	unconstrained · MANE · 19 kb · p 2.5e-23 · regional, not allelic
Overall
CADD	25.1	PHRED · no single calibrated threshold — expert panels disagree

ClinVar classifies this uncertain; the computational predictors unanimously lean tolerated — a triage signal, not a reclassification

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

Population frequency

gnomAD v4.1 · exomes + genomes

Grpmax group 0.000932% European (non-Finnish) · 11/1,180,042 alleles

Filtering AF 0.0005% ClinGen BA1/BS1 input FAF95, joint · FAF99 0.000366%

Overall 0.000682% 11/1,614,028 alleles · very rare

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: COL1A2
Protein: p.Pro261Thr
Coding: c.781C>A
MANE Select: NM_000089
dbSNP: rs141075408
Type: single nucleotide variant
Location: chr7:94408812 (GRCh38)
Gene constraint: LOEUF 0.339 · pLI 1.00 · ClinGen HI 0/3 (gnomAD)
Structure: AlphaFold pLDDT 55.02 · 5 PDB
Residue 261: the 'disordered' region

Full COL1A2 gene report on Sugi Atlas → Gene function, pathways, protein structure, interactions & more

Disease context

osteogenesis imperfecta type 1 — disease report on Sugi Atlas → Associated genes, phenotypes, clinical trials & treatments

Also linked: Ehlers-Danlos syndrome, classic type, 1

Similar variants

COL1A2 p.Pro261= Benign/Likely benign ★★ same residue
COL1A2 p.Pro261Ala Uncertain significance ★ ⚠ same residue
COL1A2 c.1197+5G>A Pathogenic ★★ same condition
COL1A2 c.1503+1G>A Pathogenic/Likely pathogenic ★★ same condition
COL1A2 c.1503+1G>C Pathogenic ★★ same condition
COL1A2 c.1557+3A>G Pathogenic ★★ same condition
COL1A2 c.2026-2A>G Pathogenic/Likely pathogenic ★★ same condition
COL1A2 c.2133+6T>A 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/col1a2-p-pro261thr (accessed [today's date]).

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