Mast cells also contribute to cardiac hypertrophy and fibrosis by synthesizing and secreting pro-hypertrophic and pro-fibrotic cytokines (e.g., TNF-α and IL-6) and growth factors [e.g., transforming growth factor (TGF)-β and basic fibroblast growth factor] (Gordon and Galli, 1990; Gordon et al., 1990; Shiota et al., 2003; Sun et al., 2007; Meléndez et al., 2010). The gene discussed is TNF; the disease is cardiac hypertrophy.