Although loss of functional Cosmc caused by mutation, deletion, or hypermethylation has been widely recognized as a prevailing mechanism underlying aberrant O‐glycosylation observed in several types of cancers including CRC,7, 9, 10, 11, 12, 13, 14 little is known why there is an elevated expression of Cosmc in CRC, which appears to contradict the data obtained from some tumour‐derived cell lines and certain types of malignancies such as pancreatic cancer.18 Here we sought to investigate the molecular mechanisms underlying elevated Cosmc expression in CRC tissues. Here, C1GALT1C1 is linked to familial pancreatic carcinoma.