Is PROC p.Arg185fs (c.552_553insTT) pathogenic?

PROC p.Arg185fs (c.552553insTT) is classified Pathogenic in PROC (ClinVar, Single submitter, 2 submitters; last evaluated 2023-07-09). Very rare (popmax 8.47e-05%, nfe); Associated with thrombophilia due to protein C deficiency, autosomal dominant.

What condition is associated with PROC p.Arg185fs (c.552_553insTT)?

PROC p.Arg185fs (c.552_553insTT) is associated with thrombophilia due to protein C deficiency, autosomal dominant (ClinVar).

How common is PROC p.Arg185fs (c.552_553insTT) in the general population?

PROC p.Arg185fs (c.552_553insTT) is very rare (popmax 8.47e-05%, nfe) (gnomAD).

PROC p.Arg185fs

Q: How is Severe hereditary thrombophilia due to congenital protein C deficiency inherited?

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

c.552_553insTT · rs1558715857 · VCV672

Pathogenic Single submitter

Classification

Pathogenic

ClinVar

Review

Single submitter ★☆☆☆

ClinVar · 2 submitters

Consequence

frameshift

predicted LoF

gnomAD v4.1

Rare

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

Conditions

thrombophilia due to protein C deficiency, autosomal dominant

Computational evidence

Protein change
Missense predictors do not apply to this variant type; conservation carries the signal.
Consequence	frameshift	predicted loss-of-function
NMD	predicted	premature termination codon in exon 7 of 9
Splicing
SpliceAI	—	not assessed · substitutions only
Constraint at this position
Conservation	phyloP 0.3	phastCons 0.96

Predicted loss-of-function is descriptive, not an applied PVS1 code.

Population frequency

gnomAD v4.1 · exomes + genomes

Grpmax group 8.47e-05% European (non-Finnish) · 1/1,180,024 alleles

Overall 6.84e-05% 1/1,461,774 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: PROC
Protein: p.Arg185fs
Coding: c.552_553insTT
MANE Select: NM_000312
dbSNP: rs1558715857
Type: Insertion
Location: chr2:127426101 (GRCh38)
Gene constraint: LOEUF 0.894 · pLI <0.01 (gnomAD)
Structure: AlphaFold pLDDT 82.35 · 12 PDB
Residue 185: a disulfide bond

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

Disease context

thrombophilia due to protein C deficiency, autosomal dominant — disease report on Sugi Atlas → Associated genes, phenotypes, clinical trials & treatments

For Severe hereditary thrombophilia due to congenital protein C deficiency (Orphanet):

Inheritance: Autosomal dominant, Autosomal recessive
Onset: Neonatal
Prevalence: 1-9 / 1 000 000 (Worldwide)

Similar variants

PROC p.Ala309Thr Pathogenic/Likely pathogenic ★★ ⚠ same condition
PROC p.Arg199Ter Pathogenic ★★ same condition
PROC p.Arg211Gln Pathogenic/Likely pathogenic ★★ ⚠ same condition
PROC p.Arg211Trp Pathogenic/Likely pathogenic ★★ ⚠ same condition
PROC p.Arg220Gln Pathogenic/Likely pathogenic ★★ ⚠ same condition
PROC p.Arg220Trp Pathogenic/Likely pathogenic ★★ ⚠ same condition
PROC p.Arg271Trp Pathogenic/Likely pathogenic ★★ same condition
PROC p.Arg272Cys 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/proc-p-arg185fs (accessed [today's date]).

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