TGFB1 and colorectal carcinoma: For example, the single-nucleotide polymorphism (SNP) 509C/T on the TGF-β1 gene promoter region can influence the infiltration of DCs at the invasive margin of the tumour, with the T-allele of the TGFB1 -509C/T SNP having a protective factor for the development of CRC.