RT Journal Article SR Electronic T1 Further delineation of the MECP2 duplication syndrome phenotype in 59 French male patients, with a particular focus on morphological and neurological features JF Journal of Medical Genetics JO J Med Genet FD BMJ Publishing Group Ltd SP jmedgenet-2017-104956 DO 10.1136/jmedgenet-2017-104956 A1 Marguerite Miguet A1 Laurence Faivre A1 Jeanne Amiel A1 Mathilde Nizon A1 Renaud Touraine A1 Fabienne Prieur A1 Laurent Pasquier A1 Mathilde Lefebvre A1 Julien Thevenon A1 Christèle Dubourg A1 Sophie Julia A1 Catherine Sarret A1 Ganaëlle Remerand A1 Christine Francannet A1 Fanny Laffargue A1 Odile Boespflug-Tanguy A1 Albert David A1 Bertrand Isidor A1 Jacqueline Vigneron A1 Bruno Leheup A1 Laetitia Lambert A1 Christophe Philippe A1 Mylène Béri-Dexheimer A1 Jean-Marie Cuisset A1 Joris Andrieux A1 Ghislaine Plessis A1 Annick Toutain A1 Laurent Guibaud A1 Valérie Cormier-Daire A1 Marlene Rio A1 Jean-Paul Bonnefont A1 Bernard Echenne A1 Hubert Journel A1 Lydie Burglen A1 Sandrine Chantot-Bastaraud A1 Thierry Bienvenu A1 Clarisse Baumann A1 Laurence Perrin A1 Séverine Drunat A1 Pierre-Simon Jouk A1 Klaus Dieterich A1 Françoise Devillard A1 Didier Lacombe A1 Nicole Philip A1 Sabine Sigaudy A1 Anne Moncla A1 Chantal Missirian A1 Catherine Badens A1 Nathalie Perreton A1 Christel Thauvin-Robinet A1 Réseau AChro-Puce A1 Jean-Michel Pedespan A1 Caroline Rooryck A1 Cyril Goizet A1 Catherine Vincent-Delorme A1 Bénédicte Duban-Bedu A1 Nadia Bahi-Buisson A1 Alexandra Afenjar A1 Kim Maincent A1 Delphine Héron A1 Jean-Luc Alessandri A1 Dominique Martin-Coignard A1 Gaëtan Lesca A1 Massimiliano Rossi A1 Martine Raynaud A1 Patrick Callier A1 Anne-Laure Mosca-Boidron A1 Nathalie Marle A1 Charles Coutton A1 Véronique Satre A1 Cédric Le Caignec A1 Valérie Malan A1 Serge Romana A1 Boris Keren A1 Anne-Claude Tabet A1 Valérie Kremer A1 Sophie Scheidecker A1 Adeline Vigouroux A1 Marilyn Lackmy-Port-Lis A1 Damien Sanlaville A1 Marianne Till A1 Maryline Carneiro A1 Brigitte Gilbert-Dussardier A1 Marjolaine Willems A1 Hilde Van Esch A1 Vincent Des Portes A1 Salima El Chehadeh YR 2018 UL http://jmg.bmj.com/content/early/2018/04/03/jmedgenet-2017-104956.abstract AB The Xq28 duplication involving the MECP2 gene (MECP2 duplication) has been mainly described in male patients with severe developmental delay (DD) associated with spasticity, stereotypic movements and recurrent infections. Nevertheless, only a few series have been published. We aimed to better describe the phenotype of this condition, with a focus on morphological and neurological features. Through a national collaborative study, we report a large French series of 59 affected males with interstitial MECP2 duplication. Most of the patients (93%) shared similar facial features, which evolved with age (midface hypoplasia, narrow and prominent nasal bridge, thick lower lip, large prominent ears), thick hair, livedo of the limbs, tapered fingers, small feet and vasomotor troubles. Early hypotonia and global DD were constant, with 21% of patients unable to walk. In patients able to stand, lower limbs weakness and spasticity led to a singular standing habitus: flexion of the knees, broad-based stance with pseudo-ataxic gait. Scoliosis was frequent (53%), such as divergent strabismus (76%) and hypermetropia (54%), stereotypic movements (89%), without obvious social withdrawal and decreased pain sensitivity (78%). Most of the patients did not develop expressive language, 35% saying few words. Epilepsy was frequent (59%), with a mean onset around 7.4 years of age, and often (62%) drug-resistant. Other medical issues were frequent: constipation (78%), and recurrent infections (89%), mainly lung. We delineate the clinical phenotype of MECP2 duplication syndrome in a large series of 59 males. Pulmonary hypertension appeared as a cause of early death in these patients, advocating its screening early in life.