Interestingly, the composition of GEMs expressed in these subtypes can be represented as a tree (Fig 2C) that mimics the development path of CD8+ T cells: All subtypes expressed GEM1, which represents a transcriptomic process shared by cells of the lymphoid lineage; expression of GEM3 differentiates tumor infiltrating and peripheral CD8+ T cells; expression of other GEMs further leads to differentiation of cells into subtypes. This evidence concerns the gene CD8A and neoplasm.