MED13L-related intellectual disability: involvement of missense variants and delineation of the phenotype.

Fiche publication


Date publication

mai 2018

Journal

Neurogenetics

Auteurs

Membres identifiés du Cancéropôle Est :
Pr FAIVRE Laurence, Pr KUENTZ Paul


Tous les auteurs :
Smol T, Petit F, Piton A, Keren B, Sanlaville D, Afenjar A, Baker S, Bedoukian EC, Bhoj EJ, Bonneau D, Boudry-Labis E, Bouquillon S, Boute-Benejean O, Caumes R, Chatron N, Colson C, Coubes C, Coutton C, Devillard F, Dieux-Coeslier A, Doco-Fenzy M, Ewans LJ, Faivre L, Fassi E, Field M, Fournier C, Francannet C, Genevieve D, Giurgea I, Goldenberg A, Green AK, Guerrot AM, Heron D, Isidor B, Keena BA, Krock BL, Kuentz P, Lapi E, Le Meur N, Lesca G, Li D, Marey I, Mignot C, Nava C, Nesbitt A, Nicolas G, Roche-Lestienne C, Roscioli T, Satre V, Santani A, Stefanova M, Steinwall Larsen S, Saugier-Veber P, Picker-Minh S, Thuillier C, Verloes A, Vieville G, Wenzel M, Willems M, Whalen S, Zarate YA, Ziegler A, Manouvrier-Hanu S, Kalscheuer VM, Gerard B, Ghoumid J

Résumé

Molecular anomalies in MED13L, leading to haploinsufficiency, have been reported in patients with moderate to severe intellectual disability (ID) and distinct facial features, with or without congenital heart defects. Phenotype of the patients was referred to "MED13L haploinsufficiency syndrome." Missense variants in MED13L were already previously described to cause the MED13L-related syndrome, but only in a limited number of patients. Here we report 36 patients with MED13L molecular anomaly, recruited through an international collaboration between centers of expertise for developmental anomalies. All patients presented with intellectual disability and severe language impairment. Hypotonia, ataxia, and recognizable facial gestalt were frequent findings, but not congenital heart defects. We identified seven de novo missense variations, in addition to protein-truncating variants and intragenic deletions. Missense variants clustered in two mutation hot-spots, i.e., exons 15-17 and 25-31. We found that patients carrying missense mutations had more frequently epilepsy and showed a more severe phenotype. This study ascertains missense variations in MED13L as a cause for MED13L-related intellectual disability and improves the clinical delineation of the condition.

Mots clés

Cardiopathy, Intellectual disability, MED13L, Mediator complex

Référence

Neurogenetics. 2018 May;19(2):93-103