Base Editor Repair Outcome Simulator (2D)

Cytosine base editing converts a single C:G base pair to T:A without cutting both DNA strands — but the raw chemistry only creates a uracil intermediate, and what the cell does with that uracil determines whether the edit actually lands, and where. This 2D canvas view lays a real 20 nt protospacer plus NGG PAM flat on the screen, highlights the deaminase's real editing window (positions 4-8), and computes a separate, position-dependent deamination probability for every cytosine that window — peaking in the middle and tapering at the edges, exactly as published base-editor efficiency profiles do. Running batches of simulated cells samples every window cytosine independently through the same stochastic repair race as the 3D model (unedited / precise C→T / silent reversion / indel), and a live per-position histogram lets you watch the bell-shaped efficiency curve emerge from the data.