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 .
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%) .
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.
Applied to two independent datasets (TBRU: 849 total eGenes; OneK1K: 985), Dynema found single-context interaction effects replicating across cohorts β allelic direction concordance 0.92β0.98 and z-score correlations 0.84β0.88 for cell-state canonical variates CV1βCV3 . 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 .
Code: Dynema.jl and Dynema_analysis.
Know what changed, what holds up, and what remains uncertain. Every Friday. No ads.