ARID1A and breast cancer: We ranked the top 20 most frequently mutated genes across our samples: AHNAK, ALMS1, ANKRD12, ARID1A, ARHGAP35, BEST1, BPTF, CALM2, F5, HIVEP1, MACF1, MDN1, MIK67, MUC3A, MUC12, MUC16, SOS1, TET2, WIPF1, ZFHX4 (Fig. 5E, Supplementary Fig. S9, Supplementary Table S8) and validated these genes in publicly available data sets using cBioPortal, comparing metastatic (n = 396) vs non-metastatic (n = 5158) BC samples.