Is ACTA2 p.Pro174= (c.522C>T) pathogenic?

ACTA2 p.Pro174= (c.522C>T) is classified Likely benign in ACTA2 (ClinVar, Single submitter, 1 submitter; last evaluated 2022-03-14). Very rare (popmax 8.47e-05%, nfe); Associated with aortic aneurysm, familial thoracic 6.

What condition is associated with ACTA2 p.Pro174= (c.522C>T)?

ACTA2 p.Pro174= (c.522C>T) is associated with aortic aneurysm, familial thoracic 6 (ClinVar).

How common is ACTA2 p.Pro174= (c.522C>T) in the general population?

ACTA2 p.Pro174= (c.522C>T) is very rare (popmax 8.47e-05%, nfe) (gnomAD).

ACTA2 p.Pro174=

Q: How is Multisystemic smooth muscle dysfunction syndrome inherited?

Typically Unknown (Orphanet). A genetic counselor can assess individual risk for a family.

c.522C>T · rs1589394088 · VCV1952641

Likely benign Single submitter

Classification

Likely benign

ClinVar

Review

Single submitter ★☆☆☆

ClinVar · 1 submitter

gnomAD v4.1

Rare

very rare (popmax 8.47e-05%, nfe)

Conditions

aortic aneurysm, familial thoracic 6

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
Pangolin	Δ0.20	gain · loss 0.00 · not in the SpliceAI release · independent
Constraint at this position
Conservation	phyloP 0.064	GERP -3.4, phastCons 0.61
Overall
CADD	9.257	PHRED · no single calibrated threshold — expert panels disagree

Population frequency

gnomAD v4.1 · exomes + genomes

Grpmax group 8.47e-05% European (non-Finnish) · 1/1,179,956 alleles

Overall 6.84e-05% 1/1,461,788 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: ACTA2
Protein: p.Pro174=
Coding: c.522C>T
MANE Select: NM_001613
dbSNP: rs1589394088
Type: single nucleotide variant
Location: chr10:88941323 (GRCh38)
Gene constraint: LOEUF 0.472 · pLI 0.99 · ClinGen HI 1/3 (gnomAD)
Structure: AlphaFold pLDDT 95.43

Full ACTA2 gene report on Sugi Atlas → Gene function, pathways, protein structure, interactions & more

Disease context

aortic aneurysm, familial thoracic 6 — disease report on Sugi Atlas → Associated genes, phenotypes, clinical trials & treatments

For Multisystemic smooth muscle dysfunction syndrome (Orphanet):

Inheritance: Unknown
Onset: Infancy

Similar variants

ACTA2 p.Pro174Ser Uncertain significance ★★ ⚠ same residue
ACTA2 p.Arg118Gln Pathogenic/Likely pathogenic ★★ same condition
ACTA2 p.Arg149Cys Pathogenic ★★ same condition
ACTA2 p.Arg149Leu Pathogenic/Likely pathogenic ★★ same condition
ACTA2 p.Arg179Cys Pathogenic ★★ same condition
ACTA2 p.Arg179His Pathogenic ★★ same condition
ACTA2 p.Arg198Cys Pathogenic/Likely pathogenic ★★ same condition
ACTA2 p.Arg198His 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/acta2-p-pro174 (accessed [today's date]).

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