Examining the afferents to cortical OPCs in the secondary motor (premotor, MOs, M2) cortex, injection of SADΔG-EGFP(EnvA) into MOs of Pdgfra::CreER-(gp4-TVA)fl mice (Figure 3B) again resulted in infection of Pdgfra+/EGFP+ starter OPCs. This evidence concerns the gene PDGFRA and infection.