An imbalance of pro-angiogenic and anti-angiogenic factors in the maternal circulation has been demonstrated during preeclampsia, specifically increased levels of the anti-angiogenic soluble fms-like tyrosine kinase 1 (sFlt-1), and reduced levels of pro-angiogenic placental growth factor (PlGF) [11,12]. This evidence concerns the gene FLT1 and preeclampsia.