Is BRCA1 p.Pro634Ser (c.1900C>T) pathogenic?

BRCA1 p.Pro634Ser (c.1900C>T) is classified Conflicting classifications of pathogenicity in BRCA1 (ClinVar, Conflicting submitters, 6 submitters; last evaluated 2025-03-12). AlphaMissense: likely benign (0.0897); Very rare (popmax 0.00133%, afr); Associated with BRCA1-related cancer predisposition.

What condition is associated with BRCA1 p.Pro634Ser (c.1900C>T)?

BRCA1 p.Pro634Ser (c.1900C>T) is associated with BRCA1-related cancer predisposition, hereditary breast ovarian cancer syndrome, breast-ovarian cancer, familial, susceptibility to, 1 (ClinVar).

How common is BRCA1 p.Pro634Ser (c.1900C>T) in the general population?

BRCA1 p.Pro634Ser (c.1900C>T) is very rare (popmax 0.00133%, afr) (gnomAD).

What do computational predictors say about BRCA1 p.Pro634Ser (c.1900C>T)?

AlphaMissense predicts likely benign (score 0.0897) — an in-silico prediction, not a clinical call.

BRCA1 p.Pro634Ser

c.1900C>T · rs80357056 · VCV54391

Conflicting classifications of pathogenicity Conflicting submitters

Classification

Conflicting classifications of pathogenicity

ClinVar

Review

Conflicting submitters ★☆☆☆

ClinVar · 6 submitters

AlphaMissense

likely benign

0.0897 · ACMG-weighted

gnomAD v4.1

Rare

very rare (popmax 0.00133%, afr)

Missense predictors

0/2 damaging

AlphaMissense, SaProt · REVEL no call

Conditions

BRCA1-related cancer predisposition

Computational evidence

Protein change
AlphaMissense	0.0897	likely benign
REVEL	0.471	indeterminate
SaProt	LLR -4.81	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 2.5	GERP -0.097, phastCons 1
Regional constraint	o/e 0.91	unconstrained · MANE · 78 kb · p 4.8e-05 · regional, not allelic
Overall
CADD	16.56	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

Grpmax group 0.00133% African / African-American · 1/74,984 alleles

Overall 0.000137% 2/1,461,792 alleles · very rare

Ancestry group	Frequency	1 in
African / African-Americangrpmax	0.00133%	74,984
European (non-Finnish)	8.47e-05%	1,180,004

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: BRCA1
Protein: p.Pro634Ser
Coding: c.1900C>T
MANE Select: NM_007294
dbSNP: rs80357056
Type: single nucleotide variant
Location: chr17:43093631 (GRCh38)
Gene constraint: LOEUF 0.885 · pLI <0.01 · ClinGen HI 3/3 (gnomAD)
Structure: AlphaFold pLDDT 41.99 · 33 PDB

Full BRCA1 gene report on Sugi Atlas → Gene function, pathways, protein structure, interactions & more

Disease context

Also linked: hereditary breast ovarian cancer syndrome breast-ovarian cancer, familial, susceptibility to, 1 hereditary neoplastic syndrome

Similar variants

BRCA1 p.Pro634Leu Conflicting classifications of pathogenicity ★ ⚠ same residue
BRCA1 p.Pro634= Likely benign ★ same residue
BRCA1 p.Pro634Arg Likely benign ★ same residue
BRCA1 p.Pro634delinsGlnIleTer Pathogenic ★★★ same residue
BRCA1 p.Pro634fs Pathogenic ★ same residue
BRCA1 c.134+3A>T Likely pathogenic ★★★ same condition
BRCA1 c.135-1G>T Pathogenic ★★★ same condition
BRCA1 c.212+1G>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/brca1-p-pro634ser (accessed [today's date]).

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