P346L
Category 3/4 — Most DruggableConflictingTransmembrane · predictedEditorialProline → Leucine at position 346 inside TM2. ClinVar Conflicting with broad clinical spectrum — Wolfram syndrome 1, Cataract 41, Wolfram-like syndrome. AlphaMissense 0.917, ΔΔG -0.62.
Interactive 3D Structure
Bond changes · DynaMut2 interaction analysis
| Interaction type | Wild-type partner | Mutant partner | Status |
|---|---|---|---|
| Hydrogen bond | F343 | — | Lost |
| Hydrogen bond | I349 | I349 | Preserved |
| Hydrogen bond | F350 | F350 | Preserved |
| Hydrogen bond | S418 | S418 | Preserved |
| Hydrogen bond | — | I421 | Gained |
| Polar contact | A342 | A342 | Preserved |
| Polar contact | — | F344 | Gained |
| Polar contact | I349 | I349 | Preserved |
| Polar contact | F350 | F350 | Preserved |
| Polar contact | — | I421 | Gained |
| Van der Waals | A342 | — | Lost |
| Hydrophobic | I421 | I421 | Preserved |
| Hydrophobic | A422 | A422 | Preserved |
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
- 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
Observed at very low frequency in gnomAD.
ClinVar classifies this variant as Conflicting classifications of pathogenicity for Wolfram syndrome (classic) (autosomal recessive, OMIM 222300); Cataract 41 (autosomal dominant, OMIM 116400); Wolfram-like syndrome (autosomal dominant, OMIM 614296); Nonsyndromic hearing loss (DFNA6/14/38) (autosomal dominant, OMIM 600965); WFS1-related diabetes (autosomal dominant). 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.
- Wolfram syndrome (classic)autosomal recessive · OMIM 222300submitted as: Wolfram syndrome 1; Wolfram syndrome 1
- Cataract 41autosomal dominant · OMIM 116400submitted as: Cataract 41
- Wolfram-like syndromeautosomal dominant · OMIM 614296submitted as: Wolfram-like syndrome
- 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
- 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.
Highest in East Asian: AF 0.0045% (2 of 44,882 alleles), 3.3x 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 group | Allele freq. | AC / AN | Hom. | Carrier est. |
|---|---|---|---|---|
| Middle Eastern · under-sampled | 0.016% | 1 / 6,082 | 0 | — |
| East Asian | 0.0045% | 2 / 44,882 | 0 | ~1 in 11220 |
| African / African American | 0.0040% | 3 / 74,894 | 0 | ~1 in 12480 |
| Admixed American | 0.0033% | 2 / 59,984 | 0 | ~1 in 15000 |
| South Asian | 0.0033% | 3 / 91,074 | 0 | ~1 in 15180 |
| Finnish · under-sampled | 0.0016% | 1 / 64,044 | 0 | — |
| European (non-Finnish) | 0.00085% | 10 / 1,180,008 | 0 | ~1 in 59000 |
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 346 sits in TM2. Neighbors: ILE345 (2.5 Å), LEU347 (2.5 Å), ILE349 (4.4 Å — partner of F350I/I349 cluster), PHE344 (4.4 Å). The local environment is uniformly hydrophobic, characteristic of a bilayer-embedded helix interior.
The wild-type proline at 346 likely defines a controlled kink in TM2's middle. Replacing it with leucine removes the kink and lets the helix straighten. The |ΔΔG| of 0.62 reflects modest fold cost; AlphaMissense 0.917 + Wolfram 1 + Cataract 41 confirm severe multi-tissue consequence. The variant is in the broader F350I TM2 cluster.
Druggability Assessment
Mechanism: loss of TM2 helix kink. Therapeutic: TM2 site-directed (same broader region as F350I).
Why this matters
Feed this card to Wolfram Intelligence
Download the P346L 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.