The initial stage of this biocollection based on the recruitment of large families for genetic linkage analysis. This is a first step to identify patients with intracranial aneurysms occurring in a family context, and to conduct a comprehensive investigation according to clinical guidelines in force to assess the potentially informative family and ensure their adherence to the prior biocollection. The next step is the fine and accurate phenotyping of each of the family members (imaging) and the collection of a blood sample for DNA extraction for molecular genetic analysis.