NOS3 and Miscarriage: Genome-wide screening has shown that siblings of patients with RSA have a greater risk of miscarriage (16), Variants associated with RSA have been detected in genes involved in the immune response (IFNG, IL10, KIR2DS2, KIR2DS3, KIR2DS4, MBL, and TNF), coagulation (F2, F5, PAI-1, and PROZ), metabolism (GSTT1 and MTHFR), hormonal regulation (ESR1 and ADRB2), angiogenesis (NOS3 and VEGFA), and endometrial and placental function (ENOS and ACE) (17–19).