In Nephrogenic diabetes insipidus, X-linked (AVPR2, OMIM 304800), the master switch sits on the ↓ DOWN branch ([F] forced below); the healthy state is the ON well. The forced corrective direction is to raise s toward ON branch (polarity: supply). Classification: ○ Novel direction-only lead. Direction only — no dose, no efficacy magnitude.
The disease maps to an R19 double-well whose corrective lever is read straight off the cusp (barrier 0.5342, γ 1.4618, spinodal 0.6803). The corrective direction is forced [F]; the agent names below are direction-concordant labels at grade [O] (no dose, no efficacy or safety magnitude). This is a research hypothesis offered to experts, not medical advice.
The emergence switch
The switch for Nephrogenic diabetes insipidus, X-linked is an R19 double-well emerged from the real proximal-promoter DNA of AVPR2. Its geometry is fixed by measured stiffness γ (never fitted); the numbers below are read directly off that cusp.
emergent axis
↓ DOWN [F]
healthy branch
ON
lesion
LOF_missense_residual
γ (stiffness)
1.4618
barrier
0.5342
spinodal
0.6803
s_on / s_off
1.2090 / -1.2090
fragility
0.29
corrective polarity
supply
forced direction
raise s toward ON branch
Chemistry feasibility (DIRECTION only [O]). small-molecule recrossing of the fold is geometrically harder (barrier 0.5342 at neutral drive; lower barrier = smaller drive to supply). [O] -- no affinity/potency/dose/efficacy asserted.
The derived corrective lever
The cusp forces a corrective direction: raise s toward ON branch. This is the load-bearing output of the framework — it is [F] forced, and it is falsifiable. 2 lever families are derived; the lead is gamma-restore (stabiliser / pharmacological chaperone).
Mechanism. supply / restore the positive drive (replace-or-agonise the missing competence)
Applies to. allele-agnostic (downstream/environmental tilt)
favoured when the switch is fragile -- a small drive shift recrosses the fold
Falsifier. If supplying/agonising AVPR2 (raising the switch drive) does NOT move the DOWN [F] switch toward the healthy branch in a AVPR2-deficient model, the h-restore(supply) lever is refuted for this axis.
Mechanism. stiffen the switch: stabilise the residual product so the healthy well re-deepens
Applies to. MISSENSE / residual-function alleles only
re-enlarges spinodal/barrier; needs a partially-functional allele
Falsifier. If a folding-stabiliser/chaperone does NOT re-deepen the healthy well for a residual AVPR2 allele (no rescue that a null allele lacks), the gamma-restore lever is refuted; null alleles are excluded by construction.
Agents mapped onto the lever
Existing agents whose known action is direction-concordant with the derived lever (status as pinned in the corpus; no dose, no efficacy magnitude).
agent (class)
dir.
status
phase
map
AVPR2 gene/function restoration (preclinical)
Conceptual switch-level arm (no clinical AVPR2 gene therapy); cf. collecting-duct gene-delivery challenge reviews
Morello 2000 J Clin Invest 105:887 (pharmacological chaperones rescue V2R mutants); Bernier 2006 J Am Soc Nephrol 17:232 (SR49059 reduced urine volume in NDI patients); Jean-Alphonse 2009 J Am Soc Nephrol 20:2190 (biased-agonist pharmacochaperones of V2R)
stabilise
investigational
2
◇ in trials
⚠ Mechanism-direction only — do not self-administer; no dose (unvalidated; set by a physician / national authority); not an approved use.
Direction-only candidate leads (corpus join)
Each lead is surfaced only because its known mechanism points the same way as the derived lever, and each comes with a source and a falsifier. None is a treatment.
Class. broad-spectrum chemical chaperone / proteostasis modulator
Mechanism. Lowers endoplasmic-reticulum stress, induces folding chaperones, and rescues secretion/thermostability of diverse misfolded MISSENSE proteins (documented for CFTR-F508del, myocilin, type-III collagen, protein C, aquaporin-2, among others). Direction: stabilise / re-deepen the fold. Allele scope: residual / missense only — cannot rescue an absent (null) product, and rescue depends on the specific allele. LOW fold-specificity: a broad modulator, not a target-specific stabiliser.
Prior-art. Broad chemical chaperone; no approved indication for this specific rare disease, so the direction match is a speculative, untested hypothesis. (These agents' actual approvals -- urea-cycle disorders for 4-PBA; cholestatic liver disease and gallstone dissolution for UDCA -- are not among the diseases they surface against here, so no broad pair qualifies as a rediscovery.)
Safety (qualitative; no magnitude). post-marketing safety profile on record (approved for urea-cycle disorders; qualitative; no magnitude)
Falsifier. If sodium phenylbutyrate (4-PBA) (a broad stabilise agent) does NOT re-deepen the healthy well / restore thermostability for a RESIDUAL AVPR2 missense allele in a nephrogenic_diabetes_insipidus_x_linked model -- i.e. produces no rescue beyond what a null allele shows -- the gamma-restore(stabilise) direction is refuted for sodium phenylbutyrate (4-PBA) here. Null / large-deletion alleles are excluded by construction.
Class. bile-acid chemical chaperone / ER-stress reducer
Mechanism. Bile-acid chemical chaperone that reduces endoplasmic-reticulum stress and assists folding of misfolded proteins; the taurine conjugate (TUDCA) is the more-studied chaperone form. Direction: stabilise the fold. Allele scope: residual / missense only. LOW fold-specificity.
Prior-art. Broad chemical chaperone; no approved indication for this specific rare disease, so the direction match is a speculative, untested hypothesis. (These agents' actual approvals -- urea-cycle disorders for 4-PBA; cholestatic liver disease and gallstone dissolution for UDCA -- are not among the diseases they surface against here, so no broad pair qualifies as a rediscovery.)
Safety (qualitative; no magnitude). post-marketing safety profile on record (approved for primary biliary cholangitis and gallstone dissolution; qualitative; no magnitude)
Falsifier. If ursodeoxycholic acid (UDCA; taurine conjugate TUDCA) (a broad stabilise agent) does NOT re-deepen the healthy well / restore thermostability for a RESIDUAL AVPR2 missense allele in a nephrogenic_diabetes_insipidus_x_linked model -- i.e. produces no rescue beyond what a null allele shows -- the gamma-restore(stabilise) direction is refuted for ursodeoxycholic acid (UDCA; taurine conjugate TUDCA) here. Null / large-deletion alleles are excluded by construction.
⚠ Mechanism-direction only — do not self-administer; no dose (unvalidated; set by a physician / national authority); not an approved use.
Evidence & provenance
What is reproduced vs. cited for this page.
element
grade
basis
R19 switch & cusp geometry (this page)
[V] verified
emerged from measured promoter γ of AVPR2; deterministic, 2×sha256 identical
corrective direction
[F] forced
forced by the cusp sign; falsifiable (see lever falsifiers)
mapped agents / leads
[O] open
direction-concordance only; corpus-pinned (2026-06-21); no dose, no efficacy/safety magnitude
Reading the agent column. VALIDATION SIGNAL -- the agent is already approved / established standard for this disease, so the direction logic recovered known clinical practice. Not a new claim by this kit. GENUINE HYPOTHESIS -- no approved indication for this disease; the direction match is a direction-only, untested [O] lead. Basis field grades the evidence (investigational here / in a related condition / off-label / speculative).