What distinguishes seed-competent from non-pathogenic tau in trans-synaptic transfer?

neurodegeneration partially_addressed composite 72%
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Composite
72%
Novelty
82%
Mechanistic
—
Druggability
—
Priority
87%
Importance
92%
Tractability
78%
Market price
50%

Description

The debate established trans-synaptic transfer as likely but didn’t resolve what molecular features make some tau species capable of templating while others are not. This distinction is critical for designing interventions that block pathological spread without disrupting normal tau function.

Source: Debate session sess_SDA-2026-04-04-gap-tau-prop-20260402003221_20260412-085642 (Analysis: SDA-2026-04-04-gap-tau-prop-20260402003221)

Resolution criteria

Resolution requires: (1) cryo-EM or smFRET structural analysis of pathogenic vs non-pathogenic tau conformers, identifying conformational features that confer seed competency (≥5 distinct conformers, n≥3 preparations each); (2) orthogonal assay (PMCA, RT-QuIC, FRET) showing correlation between conformer type and seeding kinetics; (3) mutation study where introducing/deleting key conformational features changes seed competency by ≥80%. Conformational differences without functional validation are insufficient.