Impact of variant density and repetitive regions on Illumina variant calling. Variant density is the number of (true or false) variants in a 100bp window centred on a call. a and b) the distribution of variant densities for true positive (TP), false positive (FP) and false negative (FN) calls. The y-axis, percent, indicates the percent of all calls of that decision that fall within the density bin on the x-axis. Illumina calls, aggregated across all samples are shown in a, while b shows Clair3 calls from simplex sup-basecalled reads at 100x depth. c) impact of repetitive regions on the F1 score (y-axis) for Clair3 (100x simplex sup) and Illumina. The x-axis indicates whether variants that fall within repetitive regions are excluded from the calculation of the F1 score. Points indicate the F1 score for a single sample.