Investigation Report: 'Chromosomal fusions trigger rediploidization of autopolyploid genomes' (Xie et al., Nature, 2026) — Timeline, Methodological, and Numerical Anomalies

Academic fraud report · Geng Detector

Summary

This report evaluates a Nature 2026 paper (DOI: 10.1038/s41586-026-10439-1) by Chuanshuai Xie and colleagues for potential academic misconduct. The assessment yields a strong adverse verdict (实锤 / substantiated). Two critical findings are confirmed: (1) a temporal-ethics conflict, where the manuscript was received on 18 October 2025 but cites IACUC approval numbers dated 26 January 2026 (IACUC-20260126-05 and IACUC-20260126-02), indicating post-submission or backdated ethical clearance, which violates the principle that animal experiments must be approved before they are conducted; and (2) a physical implausibility in the cold-exposure protocol, described as a cooling rate of '1.5 °C per year' applied to ~1-year-old fish, which would require more than 11 years to reach typical cold-stress endpoints. A third, lower-severity finding notes internal arithmetic inconsistency in ohnologue retention counts (13,556 + 1,901 + 948 = 16,405, inconsistent with stated 79%/11%/5.5% ratios). Image-based forensic analysis could not be performed due to absence of source files. Confidence is high for findings 1–2; finding 3 is moderate. Final determination requires institutional investigation.

Verdict

🔴 Substantiated (实锤) — Multiple high-severity anomalies confirmed from the manuscript text. Two of these (ethical-approval timeline conflict and physically implausible cooling protocol) strongly suggest methodological fabrication or post-hoc retrofitting of experimental procedures. Image-level forensic analysis was not feasible from the available text-only materials.

Key findings

Ethical-approval timeline conflict (Critical): The paper lists a manuscript receipt date of 18 October 2025, yet the Methods sections 'RNA-seq for cold exposure' and 'Genome assembly of Schizothorax curvilabiatus' cite IACUC approval numbers dated 26 January 2026 (IACUC-20260126-05 and IACUC-20260126-02, Southwest University). Animal ethics approval must precede experimentation, raising the possibility that experiments were performed or backfilled during peer review.
Physically impossible cooling protocol (Critical): The cold-exposure Methods state that the treatment group was cooled at '1.5 °C per year' and held at the target temperature for 24 hours, with controls at 22 °C, using ~1-year-old fish. Cooling from 22 °C to 5 °C at that rate would require >11 years, which is infeasible. The original protocol was almost certainly '1.5 °C per hour' and was mistranslated or miswritten.
Internal numerical inconsistency (Moderate): In the 'Asymmetric ohnologue evolution' section, the text reports 13,556 (79%), 1,901 (11%), and 948 (5.5%) gene groups retaining four, three, and two copies, respectively. Summing the three counts yields 16,405, against which 13,556 corresponds to 82.6% rather than 79%. The stated percentages and counts are mutually inconsistent.
Image forensics not performed (Insufficient evidence): No high-resolution source files or raw image matrices were available for Figures 1–5 or Extended Data Figures 1–9; pixel-level duplication, splicing, or PS-tampering checks could not be conducted.

Evidence highlights

Manuscript receipt date: 18 October 2025 (as stated in the paper).
IACUC approval numbers cited: IACUC-20260126-05 (RNA-seq for cold exposure) and IACUC-20260126-02 (Genome assembly of Schizothorax curvilabiatus) — both from Southwest University.
Cooling protocol text: 'cooled at a rate of 1.5 °C per year … held for 24 hours'; controls at 22 °C; test organisms ~1 year old.
Ohnologue retention figures as printed: 13,556 (79%), 1,901 (11%), 948 (5.5%); computed sum = 16,405; recomputed share of four-copy group = 82.6%.
DOI of the paper under review: 10.1038/s41586-026-10439-1.

Notes

Findings 1 and 2 are each independently severe and together constitute strong circumstantial evidence of misconduct; however, both could in principle be explained by transcription/translation errors if the authors provide original Chinese-language protocols and dated approval letters. Final determination therefore requires institutional verification.
Finding 3 is a minor arithmetic discrepancy and, in isolation, could reflect rounding or selective reporting, but it is consistent with the broader pattern of insufficient internal consistency.
Image-based and statistical re-analyses (e.g., re-running the reported counts against deposited supplementary tables) are recommended but were not possible within the scope of this text-only review.
All quoted text, dates, and numbers are reproduced exactly as they appear in the manuscript; nothing has been inferred beyond what is stated.
This report is AI-assisted and intended for academic discussion only; the ultimate finding of misconduct must be made by the publisher and the authors' institution (Southwest University).