Among preterm neonates who eventually developed ROP, some researchers found that VEGF concentrations in the early period of life in cord blood at birth and circulating blood are significantly lower than those in their non-ROP counterparts [72,85,86], while some observed the opposite results [87,88,89] and others found no difference [40,58,90]. The gene discussed is VEGFA; the disease is retinopathy of prematurity.