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R732C

Category 3/4 — Most DruggableConflictingLumenal · predictedσ-1 candidateEditorial
ArginineCysteine at position 732 · C-terminal lumenal domain (653-869) · WFS1 (Wolframin)

Arginine → Cysteine at position 732 in lumenal domain. ClinVar Conflicting including monogenic diabetes, Wolfram, T2D. AlphaMissense 0.637, ΔΔG -0.83. Charge loss + thiol near C733-C765 disulfide region.

Interactive 3D Structure

Wild-type reference
Wild-type R732 — ionic bond to D729
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DynaMut2 mutant · R732C
Mutant C732 — ionic bond to D729 lost (4 contacts lost)
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Bond changes · DynaMut2 interaction analysis

4 lost3 gained7 preserved
Interaction typeWild-type partnerMutant partnerStatus
Ionic bondD729Lost
Hydrogen bondI720Gained
Hydrogen bondN721Lost
Hydrogen bondG728G728Preserved
Hydrogen bondD729D729Preserved
Hydrogen bondG736G736Preserved
Polar contactN721Lost
Polar contactG728G728Preserved
Polar contactD729D729Preserved
Polar contactW730Gained
Polar contactG736G736Preserved
Van der WaalsG728Gained
HydrophobicI720Lost
HydrophobicC765C765Preserved

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
-0.83kcal/mol
Destabilising — mild
AlphaMissense
0.637
LPath
AlphaFold pLDDT
89
model confidence
Schema
Cat 3/4
Category 3/4 — Most Druggable
ΔΔG confidence: Standard confidence · Lumenal

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; Wolfram syndrome 1; Type 2 diabetes mellitus
InheritanceMulti-phenotype.
Population frequency (gnomAD v4)Ultra-rare · AF 0.0047%
cDNA changec.2194C>T
ClinVar accessionVCV000215396
Last evaluated2025/09/23 00:00

Observed at very low frequency in gnomAD.

Classified for1★ unverified submission

ClinVar classifies this variant as Conflicting classifications of pathogenicity for WFS1-related diabetes (autosomal dominant); Wolfram syndrome (classic) (autosomal recessive, OMIM 222300); Wolfram-like syndrome (autosomal dominant, OMIM 614296); Cataract 41 (autosomal dominant, OMIM 116400); Nonsyndromic hearing loss (DFNA6/14/38) (autosomal dominant, OMIM 600965). 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.

  • WFS1-related diabetesautosomal dominantsubmitted as: Monogenic diabetes; 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
  • Cataract 41autosomal dominant · OMIM 116400submitted as: Cataract 41; Myopia, high, with cataract and vitreoretinal degeneration
  • Nonsyndromic hearing loss (DFNA6/14/38)autosomal dominant · OMIM 600965submitted as: Autosomal dominant nonsyndromic hearing loss 6
  • 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 0.0047% · 75 / 1,612,554 alleles
Homozygotes
0
Highest-frequency population
Middle Eastern · AF 0.066%

Highest in Middle Eastern: AF 0.066% (4 of 6,084 alleles), 14.1x 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.
Middle Eastern0.066%4 / 6,0840~1 in 760
East Asian0.0089%4 / 44,8760~1 in 5610
South Asian0.0066%6 / 91,0660~1 in 7590
Remaining individuals0.0064%4 / 62,4540~1 in 7810
European (non-Finnish)0.0045%53 / 1,179,9040~1 in 11130
Admixed American0.0033%2 / 59,9780~1 in 14990
African / African American0.0027%2 / 74,9460~1 in 18740

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 732 sits next to C733 (3.5 Å from C765 in the inferred disulfide). Neighbors: CYS733 (2.5 Å), MET731 (2.5 Å), ASP729 (3.7 Å — partner of G728-D729 region), GLY728 (3.8 Å).

The wild-type R732 is the same R732 referenced as a partner in G736R Atlas card. R732C replaces this critical arginine with a free cysteine — adjacent to C733 (which forms a disulfide with C765). The new C732 could potentially form aberrant disulfide chemistry with C733 itself, disrupting the C733-C765 disulfide entirely.

|ΔΔG| 0.83 + AM 0.637 + multi-phenotype confirm severe consequence.

Amino-acid chemistry
Arginine (R) → Cysteine (C) — positively-charged guanidinium replaced by thiol.
Position in the protein
C-terminal lumenal domain · position 732 (pLDDT 89). Adjacent to C733 (in C733-C765 disulfide).

Druggability Assessment

Category 3/4 — Most Druggable. |ΔΔG| = 0.83. AlphaMissense 0.637 + multi-phenotype confirm severe consequence.

Mechanism: loss of R732 charge + potential aberrant disulfide with C733 disrupting the C733-C765 structural disulfide. Therapeutic: site-directed at the R732-C733-C765 microregion.

Why this matters

R732C is one of the most dangerous R→C class variants — it sits adjacent to a structural disulfide cysteine, creating a real risk of aberrant disulfide formation that disrupts the wild-type disulfide.
Therapeutic Strategy Handoff · prediction

Feed this card to Wolfram Intelligence

Download the R732C 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 R732C PDF card ↓Strategies are AI-generated predictions, not validated therapeutics.

UniProt Domain Annotation

Chain1890 · Wolframin
Topological domain653869 · Lumenal