Retroviral genetic transduction of the single-chain variable domain anti-carcinoembryonic Ag (CEA) Fcε receptor I γ-chain fusion (scFv anti-CEA) receptor amplified expression of this receptor in naïve mouse T lymphocytes as shown by Darcy et al. Additionally, they established that the altered T-cells were capable of inducing CEA-positive cell lysis via perforin-mediated pathways and emphasized the importance of interferon γ in colorectal tumor control. This evidence concerns the gene CEACAM5 and colorectal neoplasm.