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A31G

Category 5 — IDR ExclusionConflictingCytoplasmic · predictedEditorial
AlanineGlycine at position 31 · N-terminal intrinsically disordered region (1-86) · WFS1 (Wolframin)

Alanine → Glycine at position 31 in wolframin's N-terminal intrinsically disordered region (IDR). ClinVar carries conflicting classifications. AlphaMissense 0.100 (likely BENIGN). pLDDT 28 — deep IDR. DynaMut2 ΔΔG -0.35 kcal/mol but NOT trustworthy. A Category 5 IDR variant flagged for wet-lab validation.

Interactive 3D Structure

Wild-type reference
Wild-type A31 — native residue, no strong sidechain contacts
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DynaMut2 mutant · A31G
Mutant G31 — energy-minimized; local contact network preserved
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Computational Predictions

DynaMut2 ΔΔG
-0.35kcal/mol
Destabilising — mild
AlphaMissense
0.100
LBen
AlphaFold pLDDT
28
model confidence
Schema
Cat 5
Category 5 — IDR Exclusion
ΔΔG confidence: Reduced confidence · Cytoplasmic
  • pLDDT 28.33 below 70

The underlying AlphaFold model has pLDDT below 70 at this position, so the structure the stability calculation was run on is itself uncertain.

Do not rank this value against a variant from a different region on ΔΔG alone.

Clinical Evidence

ClinVar classificationConflicting classifications of pathogenicity
Review statuscriteria provided, conflicting classifications
Associated conditionsInborn genetic diseases; Wolfram syndrome 1
InheritanceInheritance pattern uncertain given conflicting ClinVar classifications. Documented in patients with Wolfram syndrome and inborn genetic diseases.
Population frequency (gnomAD v4)Ultra-rare · AF 0.0070%
cDNA changec.92C>G
ClinVar accessionVCV000215373
Last evaluated2025/09/10 00:00

Observed at very low frequency in gnomAD.

Classified for1★ unverified submission

ClinVar classifies this variant as Conflicting classifications of pathogenicity for Wolfram syndrome (classic) (autosomal recessive, OMIM 222300). Classic Wolfram syndrome is recessive: a single copy does not produce it, and this classification says nothing about a carrier's own risk.

  • Wolfram syndrome (classic)autosomal recessive · OMIM 222300submitted as: Wolfram syndrome 1
  • Submitters conflict on this classification (1★). Treat the conditions above as submitted, not as documented phenotypes.
  • Phenotype scope is interpretation of submitted records. The computed values on this card (AlphaMissense, DynaMut2 ΔΔG, pLDDT) are measurements of the model, not of a patient.
  • Presentation cannot be generalised from neighbouring variants: one nucleotide over can present very differently. Structural similarity supports a mechanistic hypothesis, never a phenotype claim.

Review status: 1★ conflicting classifications. ClinVar "conditions" is the union of all submissions; 0–1★ entries are submitted conditions, not documented phenotypes.

Population frequency
Global (all ancestries)
AF 0.0070% · 111 / 1,590,016 alleles
Homozygotes
0
Highest-frequency population
African / African American · AF 0.107%

Highest in African / African American: AF 0.107% (80 of 74,724 alleles), 15.3x the global figure. The global AF describes the general population, not the at-risk group.

No homozygotes reported in gnomAD v4. For a recessive allele this is expected and is not, on its own, evidence either way.

Ancestry groupAllele freq.AC / ANHom.Carrier est.
African / African American0.107%80 / 74,7240~1 in 470
Admixed American0.018%10 / 56,6720~1 in 2830
Remaining individuals0.0097%6 / 61,6440~1 in 5140
European (non-Finnish)0.0013%15 / 1,168,8660~1 in 38960

Source: gnomAD r4, retrieved 2026-08-21. Values are allele frequencies. The carrier estimate is derived from the allele frequency (Hardy-Weinberg, ~2·AF) and is an approximation, not a published figure — where a published carrier frequency exists it outranks this column and is cited on the card.

Structural Context

Position 31 sits in wolframin's N-terminal IDR. The pLDDT score of 28 indicates that AlphaFold cannot reliably predict the local conformation — the protein adopts an ensemble of structures in this region rather than a single fold. Neighbor analysis returns only the immediate sequence neighbors (SER32 at 2.5 Å, THR30 at 2.6 Å, LEU33 at 4.6 Å) — the structural signature of IDR.

Replacing alanine with glycine adds backbone flexibility. Glycine permits backbone conformations (especially in the Ramachandran left-handed helix region) that other amino acids cannot adopt. In a folded protein this is sometimes structurally significant. In an IDR, where the protein is already conformationally heterogeneous, the impact is more subtle — the ensemble's accessible conformational space shifts slightly, but no single 'wild-type' geometry is being broken.

DynaMut2's |ΔΔG| of 0.35 kcal/mol is not interpretable as a quantitative claim in this region. AlphaMissense's 0.100 score (well below the 0.564 pathogenic threshold) considers the variant likely benign.

The conflicting ClinVar classifications — some pathogenic, some uncertain — likely reflect that this variant has been observed in patients with Wolfram-spectrum disease but causal contribution has not been firmly established. The mechanism, if pathogenic, would likely involve IDR-mediated phase separation, partner binding through disordered regions, or context-dependent functional disruption — none of which AlphaMissense's training reliably captures.

Amino-acid chemistry
Alanine (A) → Glycine (G) — a small hydrophobic methyl-bearing residue replaced by the smallest amino acid (no side chain). The substitution removes a methyl group and adds backbone flexibility.
Position in the protein
N-terminal intrinsically disordered region (residues 1–86) · position 31 sits in a region with pLDDT 28, deep in IDR territory. The AlphaFold model is not predictive here.

Druggability Assessment

Category 5 — IDR Exclusion. pLDDT = 28 places this variant deep in wolframin's IDR. DynaMut2 stability predictions are not trustworthy here. AlphaMissense's score of 0.100 (likely benign) raises a substantive question about whether the variant is genuinely pathogenic or is a benign variant observed by association.

The Atlas routes Category 5 variants to wet-lab characterization rather than computational drug discovery. For A31G specifically, the recommended next steps are: (1) verify the clinical association with case-by-case review; (2) characterize the IDR's functional role; (3) test the variant in functional assays. Therapeutic strategy decisions should not be made on the current computational data alone.

Why this matters

A31G is one of two IDR-pair Category 5 variants in this batch (with G78R). Both sit in wolframin's N-terminal disordered region, both have AlphaMissense scores in the likely-benign range, both carry conflicting ClinVar classifications. The Atlas appropriately flags these as exclusions from the computational drug discovery pipeline. Pre-atlas analysis might have included them as therapeutic targets; the Atlas's IDR-exclusion logic is what prevents that misallocation of effort.
Therapeutic Strategy Handoff · prediction

Feed this card to Wolfram Intelligence

Download the A31G PDF below and upload it to Wolfram Intelligence to generate therapeutic-strategy proposals — guanidinium mimetics, sigma-1 agonist docking, NAC thiol-capping. NAC is already on the bench-testing list.

Download A31G PDF card ↓Strategies are AI-generated predictions, not validated therapeutics.

UniProt Domain Annotation

Chain1890 · Wolframin
Region1321 · Interaction with ATP6V1A
Region186 · Disordered