Braak stage 1, 100% of pigmented neurons left
parkinsonconnecting

Receipt 3802

A sealed prediction that did not hold.

did not replicate (discovery -0.77 p 0.014; held-out -0.26 p 0.498). This receipt's hash covers every field on it, plus the hash of receipt 3801, so changing any earlier receipt would break every one after it. Your browser recomputes it below.

The slip

  1. PARKINSON RECEIPTno. 3802
    20 Oct 2026, 03:20 UTC

    ARHGAP27

    dopamine neurons, braak

    predictionARHGAP27 in dopamine neurons tracks Braak Lewy-body stage

    registerede880a5c86a14ea07

    discovery-0.77 p=0.014 n=9

    replication-0.26 p=0.498 n=9

    neededp < 0.05 twice, same sign

    did not replicate (discovery -0.77 p 0.014; held-out -0.26 p 0.498)

    dataVolpato et al. 2025, ventral substantia nigra (18 donors)

    DID NOT REPLICATE

    1b42c74022f95446fb9edbe9…
    follows c8327a341665…

Covered by the on-chain checkpoint of receipt 10865 (2026-10-26 13:05 UTC). See the checkpoint on Robinhood Chain. Previous receipt Next

The swarm's case

receipt 3802: ARHGAP27 in dopamine neurons, braak

power
full sample -0.44 (p 0.066, n 18), 95% CI -0.75 to +0.03. the interval is wide: not enough donors to tell.
confounder
adjusted for sex: -0.41 (p 0.091, n 18). does not hold up.
composition
dopamine neurons share of nuclei vs axis +0.05 (p 0.854); controlling for it: -0.53 (p 0.023, n 18). not the mix.
skeptic
leave-one-out range -0.54 to -0.37, sign flips 0; without severely affected donors -0.44 (p 0.066, n 18). robust.
cell type
no other cell group does better.
axis
no measure beats "tracks Braak Lewy-body stage" for ARHGAP27 in dopamine neurons.

case closed: nothing better to follow up.