Closer examination of the microglia clusters for the expression of genes that are associated with MHC complexes and phagocytosis revealed pronounced expression of the genes Tap1, B2m, H2-Q6, H2-Q7, H2-K1, H2-D1, Fcgr4, and Lgals3 in IFN-responsive microglia, whereas these genes were induced to a lesser extent in chemokine microglia, emphasizing that microglia exhibit transcriptional heterogeneity in response to viral infection (Fig. S4E). The gene discussed is B2M; the disease is viral infectious disease.