BRAT1-related disorders: phenotypic spectrum and phenotype-genotype correlations from 97 patients.

Engel, Camille Valence, Stéphanie Delplancq, Geoffroy Maroofian, Reza Accogli, Andrea Agolini, Emanuele Alkuraya, Fowzan S Baglioni, Valentina Bagnasco, Irene Becmeur-Lefebvre, Mathilde Bertini, Enrico Borggraefe, Ingo Brischoux-Boucher, Elise Bruel, Ange-Line Brusco, Alfredo Bubshait, Dalal K Cabrol, Christelle Cilio, Maria-Roberta [UCL] Cornet, Marie-Coralie Coubes, Christine Danhaive, Olivier [UCL] Delague, Valérie Denommé-Pichon, Anne-Sophie Di Giacomo, Marilena Carmela Doco-Fenzy, Martine Engels, Hartmut Cremer, Kirsten Gérard, Marion Gleeson, Joseph G Heron, Delphine Goffeney, Joanna Guimier, Anne Harms, Frederike L Houlden, Henry Iacomino, Michele Kaiyrzhanov, Rauan Kamien, Benjamin Karimiani, Ehsan Ghayoor Kraus, Dror Kuentz, Paul Kutsche, Kerstin Lederer, Damien Massingham, Lauren Mignot, Cyril Morris-Rosendahl, Déborah Nagarajan, Lakshmi Odent, Sylvie Ormières, Clothilde Partlow, Jennifer Neil Pasquier, Laurent Penney, Lynette Philippe, Christophe Piccolo, Gianluca Poulton, Cathryn Putoux, Audrey Rio, Marlène Rougeot, Christelle Salpietro, Vincenzo Scheffer, Ingrid Schneider, Amy Srivastava, Siddharth Straussberg, Rachel Striano, Pasquale Valente, Enza Maria Venot, Perrine Villard, Laurent Vitobello, Antonio Wagner, Johanna Wagner, Matias Zaki, Maha S Zara, Federizo Lesca, Gaetan Yassaee, Vahid Reza Miryounesi, Mohammad Hashemi-Gorji, Farzad Beiraghi, Mehran Ashrafzadeh, Farah Galehdari, Hamid Walsh, Christopher Novelli, Antonio Tacke, Moritz Sadykova, Dinara Maidyrov, Yerdan Koneev, Kairgali Shashkin, Chingiz Capra, Valeria Zamani, Mina Van Maldergem, Lionel Burglen, Lydie Piard, Juliette et al.[show all]

BRAT1 biallelic variants are associated with rigidity and multifocal seizure syndrome, lethal neonatal (RMFSL), and neurodevelopmental disorder associating cerebellar atrophy with or without seizures syndrome (NEDCAS). To date, forty individuals have been reported in the literature. We collected clinical and molecular data from 57 additional cases allowing us to study a large cohort of 97 individuals and draw phenotype-genotype correlations. Fifty-nine individuals presented with BRAT1-related RMFSL phenotype. Most of them had no psychomotor acquisition (100%), epilepsy (100%), microcephaly (91%), limb rigidity (93%), and died prematurely (93%). Thirty-eight individuals presented a non-lethal phenotype of BRAT1-related NEDCAS phenotype. Seventy-six percent of the patients in this group were able to walk and 68% were able to say at least a few words. Most of them had cerebellar ataxia (82%), axial hypotonia (79%) and cerebellar atrophy (100%). Genotype-phenotype correlations in our cohort revealed that biallelic nonsense, frameshift or inframe deletion/insertion variants result in the severe BRAT1-related RMFSL phenotype (46/46; 100%). In contrast, genotypes with at least one missense were more likely associated with NEDCAS (28/34; 82%). The phenotype of patients carrying splice variants was variable: 41% presented with RMFSL (7/17) and 59% with NEDCAS (10/17).