In response to the stroke stress, many cytokines such as brain-derived neurotrophic factor (BDNF), vascular endothelial growth factor (VEGF), insulin-like growth factor-1, and fibroblast growth factor-2 participate in proliferation of progenitor cells in both the SVZ and SGZ (Wiltrout et al., 2007). The gene discussed is VEGFA; the disease is stroke disorder.