The spectrum of mutations in TCF7L2 in CRC encompasses single nucleotide exchanges and small insertions/deletions leading to nonsense, missense, and frame-shift mutations throughout the entire coding region, as well as translocations, copy number changes and deep deletions, many of which are likely to result in alleles with partial or complete TCF7L2 loss-of-function [2, 17, 18]. The gene discussed is TCF7L2; the disease is colorectal carcinoma.