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     Quick Explanation



    Dynema is a Julia-implemented Poisson GLM with cluster-robust variance estimators that maps cell-state-dependent eQTLs genome-wide at single-cell resolution, with calibrated type I error, ~1.4 s per test in ~500,000 cells, cross-dataset replication, and autoimmune-disease colocalization such as TSPAN32 with rheumatoid arthritis


     Long Explanation



    What Dynema Is

    Dynema is a computational method for genome-wide, cell-state-dependent eQTL mapping at single-cell resolution. It uses a Poisson GLM with cluster-robust variance estimators (CRVE) and score/Lagrange multiplier tests, implemented in Julia. The motivating problem: pseudobulk eQTL approaches average away cell-state-dependent regulatory effects, and existing single-cell mixed models (scPME, CellRegMap, scLME) are both computationally heavy and statistically miscalibrated .

    Evidence 1: Statistical Calibration

    Under a genotype-permuted null in TBRU memory T cells (259 donors, ~500,089 cells), Dynema's analytical and bootstrap p-values were <0.01 in only 0.8% and 0.7% of interaction tests β€” close to the nominal 1%. Inflated false positives hit scPME (2.6%), CellRegMap (4.6%), and scLME (3.9%) .

    Evidence 2: Speed and Scaling

    On ~500,000 cells, Dynema completed a multi-context interaction test in ~1.4 seconds per variant-gene pair β€” 10.5Γ— faster than scPME and 1442Γ— faster than CellRegMap . Because the method is applied test-by-test per variant-gene pair, this speed is what makes genome-wide scanning feasible.

    Evidence 3: Biological Results

    Applied to two independent datasets (TBRU: 849 total eGenes; OneK1K: 985), Dynema found single-context interaction effects replicating across cohorts β€” allelic direction concordance 0.92–0.98 and z-score correlations 0.84–0.88 for cell-state canonical variates CV1–CV3 . Critically, after conditioning on the lead main eQTL, 71 (27%) and 117 (43%) interaction eGenes remained significant in TBRU and OneK1K β€” many cell-state effects are genetically distinct from main effects . At TSPAN32, the interaction effect colocalized with seropositive rheumatoid arthritis GWAS (PP.H4 = 0.99 TBRU, 0.98 OneK1K) while the main effect did not .

    Limitations and What Could Change These Conclusions

    • CRVE assumes donor independence β€” related individuals are out of scope; robustness can degrade in small samples (partially addressed by score bootstrapping) .
    • Only resting peripheral T cells were analyzed; other cell types, tissues, and activated/disease states are untested, and calibration beyond two T cell cohorts is unknown.
    • The TSPAN32 colocalization is correlational β€” it implies shared causal variants, not proven causal mechanisms.
    • Falsification: a null benchmark in another large single-cell eQTL dataset with >1% of Dynema interaction tests significant at p<0.01 would undermine the calibration claim.

    Code: Dynema.jl and Dynema_analysis.



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    Updated: September 08, 2026

     Hypothesis Graveyard



    Single-cell mixed models (scPME, CellRegMap, scLME) are the natural framework for context eQTLs β€” rejected empirically here because they show 3-5Γ— inflated type I error and are up to 1442Γ— slower than the simpler CRVE approach.


    Cell-state-dependent eQTLs are mostly the same variants as main eQTLs β€” rejected: 27-43% of interaction eGenes remain significant after conditioning on the lead main variant.

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