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D118A

Category 4 — Stable Fold, Function DisruptedConflictingCytoplasmic · predictedEditorial
AspartateAlanine at position 118 · N-terminal cytoplasmic domain (87-313) · WFS1 (Wolframin)

Aspartate → Alanine at position 118 in N-terminal cytoplasmic domain. ClinVar Conflicting including monogenic diabetes. AlphaMissense 0.35 (below threshold) — AM under-call. DynaMut2 ΔΔG -0.14 kcal/mol (mild destabilising).

Interactive 3D Structure

Wild-type reference
Wild-type D118 — hydrogen bond to L121
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DynaMut2 mutant · D118A
Mutant A118 — hydrogen bond to L121 lost (2 contacts lost)
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Bond changes · DynaMut2 interaction analysis

2 lost0 gained5 preserved
Interaction typeWild-type partnerMutant partnerStatus
Hydrogen bondL121Lost
Hydrogen bondN122N122Preserved
Polar contactE120E120Preserved
Polar contactL121L121Preserved
Polar contactN122N122Preserved
Van der WaalsE120Lost
HydrophobicL121L121Preserved

Lost / gained / preserved interatomic contacts at the variant residue, from the DynaMut2 (Arpeggio) interaction analysis of the wild-type and energy-minimized mutant structures.

Computational Predictions

DynaMut2 ΔΔG
-0.14kcal/mol
Destabilising — mild
AlphaMissense
0.352
Amb
AlphaFold pLDDT
82
model confidence
Schema
Cat 4
Category 4 — Stable Fold, Function Disrupted
ΔΔG confidence: Standard confidence · Cytoplasmic

This variant is in a water-facing region, which is the regime the stability predictor was built and benchmarked for. Ordinary predictor error still applies.

Clinical Evidence

ClinVar classificationConflicting classifications of pathogenicity
Review statuscriteria provided, conflicting classifications
Associated conditionsMonogenic diabetes
InheritanceMonogenic diabetes.
Population frequency (gnomAD v4)Low frequency · AF 0.049%
cDNA changec.353A>C
ClinVar accessionVCV000178584
Last evaluated2026/01/21 00:00

Observed in the general population.

Classified for1★ unverified submission

ClinVar classifies this variant as Conflicting classifications of pathogenicity for WFS1-related diabetes (autosomal dominant). These are dominant WFS1-related disorders and are clinically distinct from classic recessive Wolfram syndrome. This classification is not a statement about Wolfram syndrome severity.

  • WFS1-related diabetesautosomal dominantsubmitted as: Monogenic diabetes
  • 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 0.049% · 794 / 1,608,038 alleles
Homozygotes
0
Highest-frequency population
African / African American · AF 0.902%

Highest in African / African American: AF 0.902% (676 of 74,986 alleles), 18.3x 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 American0.902%676 / 74,9860~1 in 55
Remaining individuals0.077%48 / 62,3160~1 in 650
Middle Eastern0.066%4 / 6,0560~1 in 760
Admixed American0.056%33 / 59,3500~1 in 900
European (non-Finnish)0.0027%32 / 1,177,6440~1 in 18400
South Asian · under-sampled0.0011%1 / 89,4440

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 118 sits in wolframin's N-terminal cytoplasmic domain. Neighbors: GLU119 (2.5 Å — adjacent existing glutamate), THR117 (2.5 Å), ASN122 (4.4 Å). The wild-type D118 + adjacent E119 form a charged surface patch in the cytoplasmic domain — likely a recognition surface for partner proteins.

Replacing D118 with alanine eliminates one of two negative charges from this patch. The local electrostatic surface is reduced; the partner-recognition geometry that depended on the D118-E119 double-negative signature is perturbed.

The |ΔΔG| of 0.14 is small — the fold absorbs the substitution. AlphaMissense's 0.35 is below threshold (AM under-call). Monogenic diabetes clinical evidence does not resolve pathogenicity (ClinVar: conflicting submissions) through cytoplasmic partner-recognition disruption.

Amino-acid chemistry
Aspartate (D) → Alanine (A) — small negatively-charged carboxylate replaced by small methyl-bearing hydrophobic. Charge lost + side chain reduced.
Position in the protein
N-terminal cytoplasmic domain · position 118 (pLDDT 82).

Druggability Assessment

Category 4 — Stable Fold, Function Disrupted (AM under-call). |ΔΔG| = 0.14. AlphaMissense 0.35 below threshold and monogenic diabetes does not resolve it (ClinVar: conflicting submissions).

Mechanism: charge loss from D118-E119 cytoplasmic surface patch. Therapeutic strategy: site-directed at the cytoplasmic recognition surface.

Why this matters

D118A is part of the charge-cluster-loss class in the N-terminal cytoplasmic domain (with similar patterns at E158K, E169K, E202G, E301K).
Therapeutic Strategy Handoff · prediction

Feed this card to Wolfram Intelligence

Download the D118A 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 D118A PDF card ↓Strategies are AI-generated predictions, not validated therapeutics.

UniProt Domain Annotation

Chain1890 · Wolframin
Region1321 · Interaction with ATP6V1A