One common form of familial AVM is Hereditary Hemorrhagic Telangiectasia, caused by autosomal dominant mutations in TGF-β/BMP-9 signaling pathway genes such as ENG, ACVRL1/ALK1, and SMAD4. Capillary malformation–arteriovenous malformation, another familial form of AVM is caused by mutations in EPHB4-RAS-ERK signaling pathway genes: RASA1 and EPHB4. One recent study systematically investigated the contribution of germline variants to bAVM and explore the critical molecular pathways underlying the pathogenesis of bAVM. Here, TGFB1 is linked to arteriovenous malformations of the brain.