Is BICD2 p.Ser331Gly (c.991A>G) pathogenic?

BICD2 p.Ser331Gly (c.991A>G) is classified Conflicting classifications of pathogenicity in BICD2 (ClinVar, Conflicting submitters, 2 submitters; last evaluated 2025-12-28). AlphaMissense: likely benign (0.0659); Very rare (popmax 0.00666%, amr); Associated with autosomal dominant childhood-onset proximal spinal muscular atrophy with contractures.

How common is BICD2 p.Ser331Gly (c.991A>G) in the general population?

BICD2 p.Ser331Gly (c.991A>G) is very rare (popmax 0.00666%, amr) (gnomAD).

What do computational predictors say about BICD2 p.Ser331Gly (c.991A>G)?

AlphaMissense predicts likely benign (score 0.0659) — an in-silico prediction, not a clinical call.

BICD2 p.Ser331Gly

Q: What condition is associated with BICD2 p.Ser331Gly (c.991A>G)?

BICD2 p.Ser331Gly (c.991A>G) 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.991A>G · rs775155214 · VCV1512331

Conflicting classifications of pathogenicity Conflicting submitters

Classification

Conflicting classifications of pathogenicity

ClinVar

Review

Conflicting submitters ★☆☆☆

ClinVar · 2 submitters

AlphaMissense

likely benign

0.0659 · ACMG-weighted

gnomAD v4.1

Rare

very rare (popmax 0.00666%, amr)

Missense predictors

0/3 damaging

AlphaMissense, REVEL, SaProt

Conditions

autosomal dominant childhood-onset proximal spinal muscular atrophy with contractures

Computational evidence

Protein change
AlphaMissense	0.0659	likely benign
REVEL	0.075	moderately benign-leaning
SaProt	LLR -6.22	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 5.1	GERP 1, phastCons 1
Regional constraint	o/e 0.84	unconstrained · MANE · 1,691 bp · p 0.0012 · regional, not allelic
Overall
CADD	21.4	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 0.00666% Admixed American · 4/60,018 alleles

Filtering AF 0.00226% ClinGen BA1/BS1 input FAF95, joint · FAF99 0.00135%

Overall 0.000342% 5/1,461,780 alleles · very rare

Ancestry group	Frequency	1 in
Admixed Americangrpmax	0.00666%	15,004
European (non-Finnish)	8.47e-05%	1,180,016

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.Ser331Gly
Coding: c.991A>G
MANE Select: NM_001003800
dbSNP: rs775155214
Type: single nucleotide variant
Location: chr9:92720371 (GRCh38)
Gene constraint: LOEUF 0.507 · pLI 0.95 (gnomAD)
Structure: AlphaFold pLDDT 78.89 · 2 PDB
Residue 331: the 'interacts with dynll1, dync1h1, dync1i2, dctn1 and dctn2' region

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.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
BICD2 p.Ala595Val 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-ser331gly (accessed [today's date]).

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