TLR4 and HELLP syndrome: Genes involved in innate immunity, such as Toll-like receptor 4 (TLR4) (Hirschfeld et al., 2006), oligomerization domain 2 (NOD2) (Rijn et al., 2008), and tumor necrosis factor (TNF)-alpha (Molvarec et al., 2008), among others, have been found to be associated with early-onset PE, HELLP syndrome, and severe FGR complicated by PE.