DEFA1 and Sepsis: Furthermore, our previous genetic association study found that the doses of genes encoding HNP1–3 (DEFA1/DEFA3), which display extensive copy number variations (CNVs) (25, 26), significantly impacted the clinical phenotype of sepsis, so that Chinese Han patients with high genetic copy number of DEFA1/DEFA3 were more susceptible to severe sepsis (defined as sepsis plus organ dysfunction according to the old criteria for defining sepsis) (27).