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Analysisstrong confidence 4 of 5: Replicated in peer-reviewed work by more than one group.king

Is the selectivity just pan-essentiality? No: it explains 0.4% of the variance

also called essentiality confound regression · residual-vs-confound control

The obvious objection to our genome-wide hit list is that genes every cell needs will look important in KMT2A-rearranged cells too, so the ranking is measuring neediness rather than anything about the fusion. We tested that directly and it is not what is happening: how essential a gene is in general predicts almost nothing about how much more the KMT2A-rearranged lines need it.

The same thing, for a scientist

Across 1,379 random protein-coding genes the KMT2A-rearranged-versus-other-leukaemia difference regressed on pan-essentiality (mean Chronos gene effect across all lines) gives difference = -0.0050 + 0.0128 x pan-essentiality, Pearson r = +0.065, r^2 = 0.0043. Residual SD 0.0701 against raw SD 0.0703: removing the confound removes essentially none of the spread. MEN1's residual z is -12.2, the most extreme of 22 probes. The sign of the slope is positive, i.e. more-essential genes show slightly LESS differential requirement, which is the opposite of the direction the objection predicts.

Go deeper
The objection, stated properly so it can be killed

The genome-wide scan ranks genes by how much more the KMT2A-rearranged lines need them than other leukaemia lines. A reviewer's first move is to say that the top of such a list is always contaminated: ribosomal proteins, proteasome subunits and spliceosome components are required by every cell, they have the most negative scores everywhere, and any difference statistic built on them inherits that floor. On this reading MEN1 ranking first is an artefact of MEN1 being broadly required, not evidence of anything fusion-specific.

That is a quantitative claim and it can be measured rather than argued about. If it is right, pan-essentiality should predict the difference statistic, and the top hits should mostly disappear once you subtract what essentiality already explains.

It explains 0.4% of the variance, and with the wrong sign

Regressing the difference on pan-essentiality across 1,379 random protein-coding genes:

quantityvalue
slope+0.0128
intercept-0.0050
Pearson r+0.065
r squared0.0043
residual SD0.0701
raw SD0.0703

Pan-essentiality accounts for 0.4% of the variance in the difference statistic. Residual SD is 0.0701 against a raw SD of 0.0703 - subtracting the confound removes about a quarter of one percent of the spread. There is nothing there to correct for.

The slope is also positive, meaning more-essential genes show slightly less differential requirement. The objection predicts the opposite sign. Whatever is driving the ranking, it is not a pan-essentiality floor.

Residuals: the controls separate from the hits, in the right direction

Each probe's residual is its difference minus what essentiality predicts, expressed as a z against the random-gene residual distribution. Negative means selectively required in the rearranged lines beyond what general neediness explains.

probepan-essentialityresidual z
MEN1-0.363-12.2
FLT3-0.147-11.9
PSIP1 (LEDGF)0.028-8.0
KMT2A-0.206-7.6
DOT1L-0.148-3.2
DPY30-0.390-0.8
ribosome (60S sample)-2.268-1.9
proteasome (20S)-2.2382.1
GAPDH-1.5431.1

The pan-essential controls behave exactly as they should once essentiality is accounted for. The ribosome sample is the most essential thing in the table (-2.27) and its residual z is only -1.86; the proteasome is equally essential and comes out at +2.12, i.e. slightly less needed by the rearranged lines. GAPDH, profoundly essential, lands at +1.14. Meanwhile MEN1 is barely essential on average (-0.363) and residual z -12.2.

So the genes at the top of the list are not the essential ones. They are a different set, and MEN1 leads it.

What this does not establish

A single linear fit on a single confound is a crude instrument, and it is the only confound tested here. Ruling out pan-essentiality does not rule out lineage, co-occurring mutations, growth rate, culture medium or screen batch - DPY30 has already failed on other designs in this project even though it passes a permutation test, and this analysis does not rescue it (residual z -0.76).

A negative residual means not explained by essentiality. It does not mean caused by the fusion. And the sample is eleven rearranged lines, none of them infant-derived, which is the population the project actually cares about.

Facts and figures
scriptanalyses/depmap-essentiality-confound/run.py
statusexecuted
run date2026-09-19
seed20260919
n random genes1379
n kmt2a rearranged11
n other leukemia43
slope0.01284
intercept-0.00499
pearson r0.0652
r squared0.0043
residual sd0.0701
raw sd0.0703
headlinePan-essentiality explains 0.4% of the variance in the difference statistic, with a positive slope - the opposite sign to the objection. MEN1 residual z = -12.2.
control problemThe pan-essential controls behave correctly: ribosome -1.86, proteasome +2.12, GAPDH +1.14. DPY30 remains unrescued at -0.76, consistent with its failures on the within-subtype, line-normalised and variance-matched designs.
caveatA linear fit on one confound is crude, and essentiality is not the only thing differing between the groups. A negative residual means 'not explained by essentiality', not 'caused by the fusion'. Eleven rearranged lines, none infant-derived.
residuals
MEN1-0.866MEN1: -0.8656FLT3-0.843FLT3: -0.8425CCND3-0.623CCND3: -0.623PSIP1-0.565PSIP1: -0.5645MEF2C-0.560MEF2C: -0.5601KMT2A-0.541KMT2A: -0.5411MYB-0.475MYB: -0.4746ZFP64-0.410ZFP64: -0.4098BCL2-0.396BCL2: -0.3959MEIS1-0.306MEIS1: -0.3056KAT7-0.296KAT7: -0.2963DOT1L-0.231DOT1L: -0.231ACTB-0.182ACTB: -0.1818Mediator-0.174Mediator: -0.1742ribosome (60S sample)-0.165ribosome (60S sample): -0.1647MLLT1-0.149MLLT1: -0.1492SEC-0.095SEC: -0.0947DPY30-0.063DPY30: -0.0631HOXA9-0.048HOXA9: -0.0479PAF1C-0.023PAF1C: -0.0232GAPDH0.055GAPDH: 0.055proteasome (20S)0.115proteasome (20S): 0.1152
residuals — the numbers behind the chart
{
  "MEN1": {
    "difference": -0.8656,
    "pan_essentiality": -0.3631,
    "residual": -0.8559,
    "residual_z": -12.2,
    "kind": "gene"
  },
  "FLT3": {
    "difference": -0.8425,
    "pan_essentiality": -0.1466,
    "residual": -0.8356,
    "residual_z": -11.91,
    "kind": "gene"
  },
  "CCND3": {
    "difference": -0.623,
    "pan_essentiality": -0.3479,
    "residual": -0.6136,
    "residual_z": -8.75,
    "kind": "gene"
  },
  "PSIP1": {
    "difference": -0.5645,
    "pan_essentiality": 0.0278,
    "residual": -0.5599,
    "residual_z": -7.98,
    "kind": "gene"
  },
  "MEF2C": {
    "difference": -0.5601,
    "pan_essentiality": -0.0385,
    "residual": -0.5546,
    "residual_z": -7.91,
    "kind": "gene"
  },
  "KMT2A": {
    "difference": -0.5411,
    "pan_essentiality": -0.2062,
    "residual": -0.5335,
    "residual_z": -7.61,
    "kind": "gene"
  },
  "MYB": {
    "difference": -0.4746,
    "pan_essentiality": -0.384,
    "residual": -0.4647,
    "residual_z": -6.63,
    "kind": "gene"
  },
  "ZFP64": {
    "difference": -0.4098,
    "pan_essentiality": -0.0051,
    "residual": -0.4047,
    "residual_z": -5.77,
    "kind": "gene"
  },
  "BCL2": {
    "difference": -0.3959,
    "pan_essentiality": -0.0362,
    "residual": -0.3904,
    "residual_z": -5.57,
    "kind": "gene"
  },
  "MEIS1": {
    "difference": -0.3056,
    "pan_essentiality": -0.053,
    "residual": -0.2999,
    "residual_z": -4.28,
    "kind": "gene"
  },
  "KAT7": {
    "difference": -0.2963,
    "pan_essentiality": -0.2999,
    "residual": -0.2875,
    "residual_z": -4.1,
    "kind": "gene"
  },
  "DOT1L": {
    "difference": -0.231,
    "pan_essentiality": -0.148,
    "residual": -0.2241,
    "residual_z": -3.2,
    "kind": "gene"
  },
  "ACTB": {
    "difference": -0.1818,
    "pan_essentiality": -0.8145,
    "residual": -0.1663,
    "residual_z": -2.37,
    "kind": "gene"
  },
  "Mediator": {
    "difference": -0.1742,
    "pan_essentiality": -0.783,
    "residual": -0.1592,
    "residual_z": -2.27,
    "kind": "complex"
  },
  "MLLT1": {
    "difference": -0.1492,
    "pan_essentiality": -0.0065,
    "residual": -0.1441,
    "residual_z": -2.06,
    "kind": "gene"
  },
  "ribosome (60S sample)": {
    "difference": -0.1647,
    "pan_essentiality": -2.2685,
    "residual": -0.1306,
    "residual_z": -1.86,
    "kind": "complex"
  },
  "SEC": {
    "difference": -0.0947,
    "pan_essentiality": -0.3879,
    "residual": -0.0847,
    "residual_z": -1.21,
    "kind": "complex"
  },
  "DPY30": {
    "difference": -0.0631,
    "pan_essentiality": -0.3896,
    "residual": -0.0531,
    "residual_z": -0.76,
    "kind": "gene"
  },
  "HOXA9": {
    "difference": -0.0479,
    "pan_essentiality": -0.1725,
    "residual": -0.0407,
    "residual_z": -0.58,
    "kind": "gene"
  },
  "PAF1C": {
    "difference": -0.0232,
    "pan_essentiality": -0.7417,
    "residual": -0.0087,
    "residual_z": -0.12,
    "kind": "complex"
  },
  "GAPDH": {
    "difference": 0.055,
    "pan_essentiality": -1.5426,
    "residual": 0.0798,
    "residual_z": 1.14,
    "kind": "gene"
  },
  "proteasome (20S)": {
    "difference": 0.1152,
    "pan_essentiality": -2.2379,
    "residual": 0.1489,
    "residual_z": 2.12,
    "kind": "complex"
  }
}
How this could bite us back
  • Refuting the loudest objection is not the same as validating the hit list. Essentiality was the easiest confound to test and it fell; the harder ones - lineage and co-occurring mutation - are still open, and a reviewer who has read this will ask for them next.
  • An r squared of 0.004 is such a complete null that it is worth asking whether the regression was set up to be able to fail. It can: the same framework puts the 20S proteasome at +2.12 and GAPDH at +1.14, which is the confound visibly doing work on the genes where it should.
Still open
  1. Does the result hold in infant-derived KMT2A-rearranged lines, of which this sample contains none?
  2. Which confound does explain the residual spread, given essentiality explains almost none of it - lineage, co-mutation, or proliferation rate?
  3. Why is the slope positive? A mild ceiling effect on already-lethal genes would do it, but that is a guess and it is testable.
Every source behind this entry (1)
  1. E1strong confidence 4 of 5: Replicated in peer-reviewed work by more than one group.database

    Across 1,379 random protein-coding genes, pan-essentiality explains 0.43% of the variance in the KMT2A-rearranged-versus-other difference statistic (r = +0.065, slope +0.0128, residual SD 0.0701 vs raw SD 0.0703). MEN1's essentiality-adjusted residual is z = -12.2, the most extreme of 22 probes, while the ribosome sample reaches only -1.86 and the 20S proteasome is +2.12.

    What this evidence cannot show

    Computed by the coordinator on 2026-09-19; script and full output are in analyses/depmap-essentiality-confound/. Eleven KMT2A-rearranged lines against 43 other leukaemia lines, rearrangement status from Cellosaurus. A linear fit on one confound is crude and essentiality is not the only thing differing between the groups. None of the eleven rearranged lines is infant-derived.

    Evidence that argues against this (1)
    • This refutes the pan-essentiality objection specifically, not the general class of confounding. The same project's within-subtype, line-normalised and variance-matched designs disagree with the permutation test about DPY30, and this analysis leaves that disagreement exactly where it was: DPY30's residual z is -0.76, comfortably inside the noise. A control that clears one confound and fails three others has not been vindicated. Broad Institute DepMap / Open Targets Platform 2026
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