a, Schematic illustrating off-target candidates arising due to multiple different haplotypes. MM, mismatch. b, Number of off-target candidates present in the 1000 Genomes dataset for each CRISPR endonuclease for 12 therapeutically relevant genes at different allele frequencies. c, Distribution of the number of off-target candidates per platinum target for each CRISPR endonuclease. d, Distribution of the number of off-target candidates per enzyme for the 4 CRISPR endonucleases studied here.