Both MSS cohorts showed a high rate of cancers (≥40%) with targeted deletion events at several loci previously associated with CRC, such as 18q21.1–18q21.2 (which includes SMAD2, SMAD4, DCC) and 17p13.1 (p53) (Table S4A in File S1). Here, SMAD4 is linked to colorectal carcinoma.