To validate the prognostic value of GPI-anchored biosynthesis related genes in BC, we develop a gene signature (GPIS) based on 21 GPI-anchored biosynthesis related genes and the characteristic factors of T cell exhaustion (TNF, IL-2, IFN-γ).The Metabric dataset, with its high number of patients, served as the training set, while the TCGA cohort, with its low number of samples, served as the validation set. The gene discussed is IFNG; the disease is breast cancer.