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W399G

Category 3/4 — Most DruggableConflictingTransmembrane · predictedEditorial
TryptophanGlycine at position 399 · Connecting loop · WFS1 (Wolframin)

Tryptophan → Glycine at position 399 in a connecting loop. ClinVar Conflicting including Cataract 41 + DFNA6. AlphaMissense 0.713, ΔΔG -1.06. Bulky aromatic → smallest amino acid.

Interactive 3D Structure

Wild-type reference
Wild-type W399 — hydrogen bond to V395
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DynaMut2 mutant · W399G
Mutant G399 — hydrophobic contact to L402 lost
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Bond changes · DynaMut2 interaction analysis

1 lost1 gained7 preserved
Interaction typeWild-type partnerMutant partnerStatus
Hydrogen bondV395V395Preserved
Hydrogen bondL402L402Preserved
Polar contactV395V395Preserved
Polar contactN396N396Preserved
Polar contactF397F397Preserved
Polar contactH401H401Preserved
Polar contactL402L402Preserved
Van der WaalsH401Gained
HydrophobicL402Lost

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
-1.06kcal/mol
Destabilising — moderate
AlphaMissense
0.713
LPath
AlphaFold pLDDT
76
model confidence
Schema
Cat 3/4
Category 3/4 — Most Druggable
ΔΔG confidence: Reduced confidence · Transmembrane
  • transmembrane position; predictor benchmarked on soluble proteins

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.

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 conditionsCataract 41; Autosomal dominant nonsyndromic hearing loss 6 (DFNA6)
InheritanceAD: DFNA6 + Cataract 41.
Population frequency (gnomAD v4)Ultra-rare · AF 0.0023%
cDNA changec.1195T>G
ClinVar accessionVCV000215386
Last evaluated2026/01/04 00:00

Observed at very low frequency in gnomAD.

Classified for1★ unverified submission

ClinVar classifies this variant as Conflicting classifications of pathogenicity for Cataract 41 (autosomal dominant, OMIM 116400); Nonsyndromic hearing loss (DFNA6/14/38) (autosomal dominant, OMIM 600965); WFS1-related diabetes (autosomal dominant); Wolfram syndrome (classic) (autosomal recessive, OMIM 222300); Wolfram-like syndrome (autosomal dominant, OMIM 614296). These are two clinically distinct disease families: classic Wolfram syndrome requires two affected copies, while the dominant WFS1-related disorders do not. One label covers both, and it does not tell you which applies to a given person.

  • Cataract 41autosomal dominant · OMIM 116400submitted as: Cataract 41
  • Nonsyndromic hearing loss (DFNA6/14/38)autosomal dominant · OMIM 600965submitted as: Autosomal dominant nonsyndromic hearing loss 6
  • WFS1-related diabetesautosomal dominantsubmitted as: Type 2 diabetes mellitus
  • Wolfram syndrome (classic)autosomal recessive · OMIM 222300submitted as: Wolfram syndrome 1; Wolfram syndrome 1
  • Wolfram-like syndromeautosomal dominant · OMIM 614296submitted as: Wolfram-like syndrome
  • 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 0.0023% · 37 / 1,613,890 alleles
Homozygotes
0
Highest-frequency population
African / African American · AF 0.031%

Highest in African / African American: AF 0.031% (23 of 74,902 alleles), 13.4x 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 American0.031%23 / 74,9020~1 in 1630
Admixed American0.012%7 / 59,8720~1 in 4280
Remaining individuals0.0048%3 / 62,4880~1 in 10410
European (non-Finnish)0.00034%4 / 1,180,0160~1 in 147500

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 399 in connecting loop. Neighbors: ASN400 (2.5 Å), GLY398 (2.5 Å — adjacent existing glycine!), ASN396 (3.9 Å), VAL395 (4.0 Å — near E394V).

Replacing W399 with glycine creates G398-G399 double-glycine motif (extra backbone flexibility) and removes the aromatic side chain entirely. Two adjacent glycines in a loop produce unusual conformational freedom. ΔΔG 1.06 reflects this. AM 0.713 + Cataract 41 + DFNA6 confirm severe consequence.

Amino-acid chemistry
Tryptophan (W) → Glycine (G) — bulky aromatic indole replaced by smallest amino acid. Massive volume loss.
Position in the protein
Connecting loop · position 399 (pLDDT 76).

Druggability Assessment

Category 3/4 — Most Druggable. |ΔΔG| = 1.06. AlphaMissense 0.713 + dual phenotypes confirm severe consequence.

Mechanism: massive volume loss + creation of G398-G399 double-glycine motif. Therapeutic: loop region site-directed.

Why this matters

W399G is in the same 392-399 loop region as E394V — multi-variant target cluster.
Therapeutic Strategy Handoff · prediction

Feed this card to Wolfram Intelligence

Download the W399G 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 W399G PDF card ↓Strategies are AI-generated predictions, not validated therapeutics.

UniProt Domain Annotation

Chain1890 · Wolframin