As one of the most crucial proinflammatory cytokines, IL-17A plays an important role in host defense against pathogen infection by stimulating cytokines (TNF-α, GM-CSF, etc) and chemokines (CXCL1, CXCL2, IL-8, etc) expression leading to neutrophil expansion and chemotaxis [2]. The gene discussed is IL17A; the disease is infection.