For example, drugs that block immune checkpoint inhibitors, such as anti-CTLA-4 and anti-PD-1/PD-L1, have been approved for use in several types of cancer and have shown promising results in clinical trials (Wojtukiewicz et al. 2021; Xiang et al. 2022; Sové et al. 2022). This evidence concerns the gene CTLA4 and cancer.