Endothelial tone and placental vascularization function as intrinsic phenotypic domains for NOS3 effects, as demonstrated by the research of Dai et al. and Zeng et al., which clarifies the genetic signal’s correlation with preeclampsia, associating T-786C and 4b/a (and, in specific models, G894T) with an increased risk and recording reduced systemic NO levels in affected individuals [48,49]. The gene discussed is NOS3; the disease is preeclampsia.