FUT6 is the major α1,3‐fucosyltransferase involved in SLex biosynthesis in colon,[4] however no upregulation of FUT6 or any other fucosyltransferases could be detected in colon cancer.[3c, 5] Therefore, the decrease in B4GALNT2 expression is responsible of the SLex expression in colon.[3c] This review focusses on the human B4GALNT2 and comprehensively summarizes the main recent findings on the roles of this gene in the control of Sda and SLex antigens biosynthesis in healthy and cancer human colon. The gene discussed is B4GALNT2; the disease is cancer.