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I338V

Category 4 — Stable Fold, Function DisruptedConflictingTransmembrane · predictedEditorial
IsoleucineValine at position 338 · Connecting loop · WFS1 (Wolframin)

Ile→Val p338 loop AM=0.06 ddg=-0.01 pLDDT=66. ClinVar Conflicting evidence. Atlas mechanism: see structural analysis.

Interactive 3D Structure

Wild-type reference
Wild-type I338 — hydrogen bond to A342
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DynaMut2 mutant · I338V
Mutant V338 — hydrogen bond to Y650 lost (3 contacts lost)
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Bond changes · DynaMut2 interaction analysis

3 lost1 gained4 preserved
Interaction typeWild-type partnerMutant partnerStatus
Hydrogen bondF341F341Preserved
Hydrogen bondA342A342Preserved
Hydrogen bondY650Lost
Polar contactF340Lost
Polar contactF341F341Preserved
Polar contactA342A342Preserved
Van der WaalsF340Lost
Van der WaalsA342Gained

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
-0.01kcal/mol
Destabilising — mild
AlphaMissense
0.061
LBen
AlphaFold pLDDT
66
model confidence
Schema
Cat 4
Category 4 — Stable Fold, Function Disrupted
ΔΔG confidence: Low confidence · Transmembrane
  • transmembrane position; predictor benchmarked on soluble proteins
  • pLDDT 66.25 below 70

This variant sits in the transmembrane band. The stability value was computed with a predictor benchmarked on water-soluble proteins. Published benchmarks of ddG predictors on membrane proteins report correlation below 0.4. Treat the magnitude as unreliable and the sign as weak evidence only.

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 conditions(no specific conditions catalogued)
InheritanceConflicting ClinVar classifications.
Population frequency (gnomAD v4)Ultra-rare · AF 0.0051%
cDNA changec.1012A>G
ClinVar accessionVCV001570306
Last evaluated2025/06/13 00:00

Observed at very low frequency in gnomAD.

Classified for1★ unverified submission

ClinVar classifies this variant as Conflicting classifications of pathogenicity, but does not state what it is classified for. ClinVar records the condition only as "not provided", "Inborn genetic diseases". A classification without a phenotype and an inheritance mode cannot be read as a statement about Wolfram syndrome risk or severity.

  • 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 0.0051% · 83 / 1,613,912 alleles
Homozygotes
1
Highest-frequency population
South Asian · AF 0.063%

Highest in South Asian: AF 0.063% (57 of 91,058 alleles), 12.2x the global figure. The global AF describes the general population, not the at-risk group.

1 homozygote reported in gnomAD v4 (1 South Asian). gnomAD excludes individuals with severe pediatric disease, so homozygotes in this dataset argue against a fully penetrant severe recessive phenotype and belong in the clinical picture. This is interpretive signal, not a classification.

Ancestry groupAllele freq.AC / ANHom.Carrier est.
South Asian0.063%57 / 91,0581~1 in 800
East Asian0.033%15 / 44,8460~1 in 1490
Middle Eastern · under-sampled0.017%1 / 6,0600
Remaining individuals · under-sampled0.0016%1 / 62,5040
European (non-Finnish)0.00076%9 / 1,179,9280~1 in 65550

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 analysis: ASP339 (2.5 Å — D339N!), THR337 (2.5 Å — T337I!), PHE340 (4.4 Å — TM2 start). Same T337I/D339N cluster. The Atlas's neighbor extraction surfaces this variant's contacts and connects them to the broader multi-variant target landscape.

Amino-acid chemistry
conservative volume reduction
Position in the protein
Connecting loop

Druggability Assessment

Cat 4 — see structural prose. AlphaMissense below threshold (AM under-call class) but mechanism is structurally identified. Therapeutic strategy: site-directed at contacts identified above, or wet-lab validation if pLDDT borderline/below 50.

Why this matters

T337I + D339N + I338V cluster.
Therapeutic Strategy Handoff · prediction

Feed this card to Wolfram Intelligence

Download the I338V 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 I338V PDF card ↓Strategies are AI-generated predictions, not validated therapeutics.

UniProt Domain Annotation

Chain1890 · Wolframin