NTRK1 and colonic neoplasm: Genomic studies have identified ∼25 genes recurrently mutated in colon tumours, leading to misregulation of five distinct signalling pathways22, 27, 28, 29: Wnt, receptor tyrosine kinase (RTK)/Ras, p53, transforming growth factor-β and PI3K (Supplementary Table 1 and Supplementary Data 1).