Is BLM p.Pro302Leu (c.905C>T) pathogenic?

BLM p.Pro302Leu (c.905C>T) is classified Uncertain significance in BLM (ClinVar, Multiple submitters, 2 submitters; last evaluated 2025-05-22). AlphaMissense: likely benign (0.3096); Absent from gnomAD v4.1; Associated with hereditary neoplastic syndrome.

What condition is associated with BLM p.Pro302Leu (c.905C>T)?

BLM p.Pro302Leu (c.905C>T) is associated with hereditary neoplastic syndrome, Bloom syndrome (ClinVar).

How common is BLM p.Pro302Leu (c.905C>T) in the general population?

BLM p.Pro302Leu (c.905C>T) is absent from gnomAD v4.1 (gnomAD).

What do computational predictors say about BLM p.Pro302Leu (c.905C>T)?

AlphaMissense predicts likely benign (score 0.3096) — an in-silico prediction, not a clinical call.

BLM p.Pro302Leu

c.905C>T · rs1895696337 · VCV1011492

Uncertain significance Multiple submitters

Classification

Uncertain significance

ClinVar

Review

Multiple submitters ★★☆☆

ClinVar · 2 submitters

AlphaMissense

likely benign

0.3096 · ACMG-weighted

gnomAD v4.1

Absent

absent from gnomAD v4.1

Missense predictors

0/2 damaging

AlphaMissense, SaProt · REVEL indeterminate

Conditions

hereditary neoplastic syndrome

Computational evidence

Protein change
AlphaMissense	0.3096	likely benign
REVEL	0.499	indeterminate
SaProt	LLR -6.00	tolerated
⇒ AlphaMissense and SaProt both call this tolerated; REVEL is indeterminate.
Splicing
SpliceAI	—	not assessed · no allele here is in the release
Constraint at this position
Conservation	phyloP 7.5	GERP 2.8, phastCons 1
Regional constraint	o/e 0.96	unconstrained · MANE · 16 kb · p 0.23 · regional, not allelic
Overall
CADD	26.2	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

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: BLM
Protein: p.Pro302Leu
Coding: c.905C>T
MANE Select: NM_000057
dbSNP: rs1895696337
Type: single nucleotide variant
Location: chr15:90751892 (GRCh38)
Gene constraint: LOEUF 0.847 · pLI <0.01 · ClinGen HI gene assoc. with recessive phenotype (gnomAD)
Structure: AlphaFold pLDDT 61.10 · 16 PDB
Residue 302: an α-helix; the 'necessary for interaction with spidr' region

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

Disease context

hereditary neoplastic syndrome — disease report on Sugi Atlas → Associated genes, phenotypes, clinical trials & treatments

Also linked: Bloom syndrome

Similar variants

BLM p.Pro302Ser Uncertain significance ★ same residue
BLM p.Pro302= Likely benign ★ same residue
BLM c.1087+1G>A Likely pathogenic ★★ same condition
BLM c.1088-1G>A Likely pathogenic ★★ same condition
BLM c.1220+2T>C Likely pathogenic ★★ same condition
BLM c.1220+2T>G Likely pathogenic ★★ same condition
BLM c.1882+2T>C Likely pathogenic ★★ same condition
BLM c.2074+1G>T 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/blm-p-pro302leu (accessed [today's date]).

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