In infections with Leishmania major, susceptibility to the infection is related to the immune response skewing towards a Th2 cell profile, with the production of anti‐inflammatory cytokines such as interleukin (IL) 4, IL‐10, IL‐13 and transforming growth factor‐beta (TGF‐β), as well as the presence of M2 macrophages, eosinophilia, increased polyamine production, decreased nitric oxide (NO) production and increased production of neutralising IgA and IgG1 antibodies [37]. The gene discussed is TGFB1; the disease is infection.