They then conducted targeted copy number and mutation screening of a replication cohort of 146 patients with familial or early‐onset CRC patients, and 28 unsequenced samples from the initial cohort (n = 39) and found 2 missense variants in Bub3 which were not present in 1154 controls and were assumed to be pathogenic. This evidence concerns the gene BUB3 and colorectal carcinoma.