This group of genes and proteins forms a highly enriched protein–protein network (STRING analysis PPI enrichment p-value 1−16) with functional enrichments in IL-15 signaling (GO: Biological Processes), T-cell receptor complex (GO: Cellular components) and KEGG pathways for primary immune deficiency and Th1 and Th2 cell differentiation (Supplemental Database S2). Here, IL15 is linked to Immunodeficiency.