My maternal great-grandfather, maternal uncle, and mother all had burst brain aneurysms; my mother fortunately survived hers. Her sister had a blood-vessel abno

My maternal great-grandfather, maternal uncle, and mother all had burst brain aneurysms; my mother fortunately survived hers. Her sister had a blood-vessel abnormality in her brain related to a benign tumor. Whether the genes / gene networks are known or not, it seems very obvious that there's something hereditary going on there. In one of the cases in the article, the 15-year-old who died had scarring in his heart and a blood relative who already had a heart implant related to arrythmias. They confirmed he had genes related to this issue as well. Seems pretty open-and-shut.