Romain Bourcier, Solena Le Scouarnec, Stéphanie Bonnaud, Matilde Karakachoff, Emmanuelle Bourcereau, Sandrine Heurtebise-Chrétien, Céline Menguy, Christian Dina, Floriane Simonet, Alexis Moles, Cédric Lenoble, Pierre Lindenbaum, Stéphanie Chatel, Bertrand Isidor, Emmanuelle Génin, Jean-François Deleuze, Jean-Jacques Schott, Hervé Le Marec, ICAN Study Group, Hubert Desal, Romain Bourcier, Benjamin Daumas-Duport, Bertrand Isidor, Jérôme Connault, Pierre Lebranchu, Thierry Le Tourneau, Marie Pierre Viarouge, Chrisanthi Papagiannaki, Michel Piotin, Hocine Redjem, Mikael Mazighi, Jean Philippe Desilles, Olivier Naggara, Denis Trystram, Myriam Edjlali-Goujon, Christine Rodriguez, Waghi Ben Hassen, Suzanna Saleme, Charbel Mounayer, Olivier Levrier, Pierre Aguettaz, Xavier Combaz, Anne Pasco, Emeline Berthier, Marc Bintner, Marc Molho, Pascale Gauthier, Cyril Chivot, Vincent Costalat, Cyril Darganzil, Alain Bonafé, Anne Christine Januel, Caterina Michelozzi, Christophe Cognard, Fabrice Bonneville, Philippe Tall, Jean Darcourt, Alessandra Biondi, Cristina Iosif, Elisa Pomero, Jean Christophe Ferre, Jean Yves Gauvrit, François Eugene, Hélène Raoult, Jean Christophe Gentric, Julien Ognard, René Anxionnat, Serge Bracard, Anne Laure Derelle, Romain Tonnelet, Laurent Spelle, Léon Ikka, Robert Fahed, Aymeric Rouchaud, Augustin Ozanne, Jildaz Caroff, Nidal Ben Achour, Jacques Moret, Emmanuel Chabert, Jérôme Berge, Gaultier Marnat, Xavier Barreau, Florent Gariel, Frédéric Clarencon, Mohammed Aggour, Frédéric Ricolfi, Adrien Chavent, Pierre Thouant, Pablo Lebidinsky, Brivael Lemogne, Denis Herbreteau, Richard Bibi, Laurent Pierot, Sébastien Soize, Marc Antoine Labeyrie, Christophe Vandendries, Emmanuel Houdart, Appoline Kazemi, Xavier Leclerc, Jean Pierre Pruvo, Sophie Gallas, Stéphane Velasco, Gervaise Loirand, Hubert Desal, Richard Redon

Intracranial aneurysms (IAs) are acquired cerebrovascular abnormalities characterized by localized dilation and wall thinning in intracranial arteries, possibly leading to subarachnoid hemorrhage and severe outcome in case of rupture. Here, we identified one rare nonsense variant (c.1378A>T) in the last exon of ANGPTL6 (Angiopoietin-Like 6)-which encodes a circulating pro-angiogenic factor mainly secreted from the liver-shared by the four tested affected members of a large pedigree with multiple IA-affected case subjects. We showed a 50% reduction of ANGPTL6 serum concentration in individuals heterozygous for the c.1378A>T allele (p.Lys460Ter) compared to relatives homozygous for the normal allele, probably due to the non-secretion of the truncated protein produced by the c.1378A>T transcripts. Sequencing ANGPTL6 in a series of 94 additional index case subjects with familial IA identified three other rare coding variants in five case subjects. Overall, we detected a significant enrichment (p = 0.023) in rare coding variants within this gene among the 95 index case subjects with familial IA, compared to a reference population of 404 individuals with French ancestry. Among the 6 recruited families, 12 out of 13 (92%) individuals carrying IA also carry such variants in ANGPTL6, versus 15 out of 41 (37%) unaffected ones. We observed a higher rate of individuals with a history of high blood pressure among affected versus healthy individuals carrying ANGPTL6 variants, suggesting that ANGPTL6 could trigger cerebrovascular lesions when combined with other risk factors such as hypertension. Altogether, our results indicate that rare coding variants in ANGPTL6 are causally related to familial forms of IA.