Is BICD2 p.Gln18Pro (c.53A>C) pathogenic?

BICD2 p.Gln18Pro (c.53A>C) is classified Uncertain significance in BICD2 (ClinVar, Single submitter, 1 submitter; last evaluated 2025-10-15). AlphaMissense: likely benign (0.1058); Very rare (popmax 8.53e-05%, nfe); Associated with autosomal dominant childhood-onset proximal spinal muscular atrophy with contractures.

How common is BICD2 p.Gln18Pro (c.53A>C) in the general population?

BICD2 p.Gln18Pro (c.53A>C) is very rare (popmax 8.53e-05%, nfe) (gnomAD).

What do computational predictors say about BICD2 p.Gln18Pro (c.53A>C)?

AlphaMissense predicts likely benign (score 0.1058) — an in-silico prediction, not a clinical call.

BICD2 p.Gln18Pro

Q: What condition is associated with BICD2 p.Gln18Pro (c.53A>C)?

BICD2 p.Gln18Pro (c.53A>C) is associated with autosomal dominant childhood-onset proximal spinal muscular atrophy with contractures (ClinVar).

Q: How is Autosomal dominant childhood-onset proximal spinal muscular atrophy inherited?

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

c.53A>C · VCV4754036

Uncertain significance Single submitter

Classification

Uncertain significance

ClinVar

Review

Single submitter ★☆☆☆

ClinVar · 1 submitter

AlphaMissense

likely benign

0.1058 · ACMG-weighted

gnomAD v4.1

Rare

very rare (popmax 8.53e-05%, nfe)

Missense predictors

0/3 damaging

AlphaMissense, REVEL, SaProt

Conditions

autosomal dominant childhood-onset proximal spinal muscular atrophy with contractures

Computational evidence

Protein change
AlphaMissense	0.1058	likely benign
REVEL	0.086	moderately benign-leaning
SaProt	LLR -5.02	tolerated
⇒ AlphaMissense, REVEL and SaProt all call this tolerated.
Splicing
SpliceAI	—	not assessed · no allele here is in the release
Constraint at this position
Conservation	phyloP 7.3	GERP 1.4, phastCons 1
Regional constraint	o/e 0.79	unconstrained · MANE · 42 kb · p 0.00095 · regional, not allelic
Overall
CADD	24.9	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 8.53e-05% European (non-Finnish) · 1/1,172,924 alleles

Overall 0.000139% 2/1,437,234 alleles · very rare

Ancestry group	Frequency	1 in
Remaining individualsnot grpmax-eligible	0.00162%	61,656
European (non-Finnish)grpmax	8.53e-05%	1,172,924

Remaining individuals shows a higher raw frequency than the grpmax group above it. gnomAD excludes bottlenecked groups — Finnish, Ashkenazi Jewish, Amish and “Remaining individuals” — from grpmax, because founder effects make their frequencies unrepresentative for filtering. The table is sorted by frequency, so an excluded group can sit above the grpmax row.

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: BICD2
Protein: p.Gln18Pro
Coding: c.53A>C
MANE Select: NM_001003800
Type: single nucleotide variant
Location: chr9:92764692 (GRCh38)
Gene constraint: LOEUF 0.507 · pLI 0.95 (gnomAD)
Structure: AlphaFold pLDDT 78.89 · 2 PDB

Full BICD2 gene report on Sugi Atlas → Gene function, pathways, protein structure, interactions & more

Disease context

autosomal dominant childhood-onset proximal spinal muscular atrophy with contractures — disease report on Sugi Atlas → Associated genes, phenotypes, clinical trials & treatments

For Autosomal dominant childhood-onset proximal spinal muscular atrophy (Orphanet):

Inheritance: Autosomal dominant
Onset: Adolescent, Antenatal, Childhood, Infancy, Neonatal
Prevalence: <1 / 1 000 000 (Worldwide)

Similar variants

BICD2 p.Gln18= Likely benign ★ same residue
BICD2 p.Arg694Cys Pathogenic/Likely pathogenic ★★ same condition
BICD2 p.Lys734Glu Likely pathogenic ★★ same condition
BICD2 p.Ser107Leu Pathogenic ★★ ⚠ same condition
BICD2 p.Thr703Met Pathogenic/Likely pathogenic ★★ same condition
BICD2 p.Tyr556Ser Likely pathogenic ★★ ⚠ same condition
BICD2 c.1062+5G>A Uncertain significance ★★ same condition
BICD2 p.Ala326Pro Uncertain significance ★★ ⚠ 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/bicd2-p-gln18pro (accessed [today's date]).

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