We accurately quantitated the abundance of each allele from next-generation sequencing (NGS) data (Methods and Extended Data Fig. 3a) and, after assessing homogeneous representation of the variants in the different pools (Extended Data Fig. 3b and Supplementary Table 2), we screened two pools (Pool4 and Pool5) encompassing the region of ARID1B at the interface with BRG1 (amino acids 1970–2130) in both cancer proliferation assay and protein stability assay (Fig. 1b and Extended Data Fig. 2c). Here, ARID1B is linked to cancer.