Developmental and epileptic encephalopathies (DEE) refer to a heterogeneous group of devastating neurodevelopmental disorders. Variants in KCNB1 have been recently reported in patients with early-onset DEE. KCNB1 encodes the alpha subunit of the delayed-rectifier voltage-dependent potassium channel Kv 2.1. We review the 37 previously reported patients carrying 29 distinct KCNB1 variants and significantly expand the mutational spectrum describing 18 novel variants from 27 unreported patients. Most variants occur de novo and mainly consist of missense variants located on the voltage sensor and the pore domain of Kv 2.1. We also report the first inherited variant (p.Arg583*). KCNB1-related encephalopathies encompass a wide spectrum of neurodevelopmental disorders with predominant language difficulties and behavioral impairment. Eighty-five percent of patients developed epilepsies with variable syndromes and prognosis. Truncating variants in the C-terminal domain are associated with a less severe epileptic phenotype. Overall, this report provides an up-to-date review of the mutational and clinical spectrum of KCNB1, strengthening its place as a causal gene in DEEs and emphasizing the need for further functional studies to unravel the underlying mechanisms.

Expanding the genetic and phenotypic relevance of KCNB1 variants in developmental and epileptic encephalopathies: 27 new patients and overview of the literature / Bar, C; Barcia, G; Jennesson, M; Le Guyader, G; Schneider, A; Mignot, C; Lesca, G; Breuillard, D; Montomoli, M; Keren, B; Doummar, D; de Villemeur, Tb; Afenjar, A; Marey, I; Gerard, M; Isnard, H; Poisson, A; Dupont, S; Berquin, P; Meyer, P; Genevieve, D; De Saint Martin, A; El Chehadeh, S; Chelly, J; Guët, A; Scalais, E; Dorison, N; Myers, Ct; Mefford, Hc; Howell, Kb; Marini, C; Freeman, Jl; Nica, A; Terrone, G; Sekhara, T; Lebre, As; Odent, S; Sadleir, Lg; Munnich, A; Guerrini, R; Scheffer, Ie; Kabashi, E; Nabbout, R. - In: HUMAN MUTATION. - ISSN 1059-7794. - 41:1(2020), pp. 69-80. [10.1002/humu.23915]

Expanding the genetic and phenotypic relevance of KCNB1 variants in developmental and epileptic encephalopathies: 27 new patients and overview of the literature.

Terrone G;
2020

Abstract

Developmental and epileptic encephalopathies (DEE) refer to a heterogeneous group of devastating neurodevelopmental disorders. Variants in KCNB1 have been recently reported in patients with early-onset DEE. KCNB1 encodes the alpha subunit of the delayed-rectifier voltage-dependent potassium channel Kv 2.1. We review the 37 previously reported patients carrying 29 distinct KCNB1 variants and significantly expand the mutational spectrum describing 18 novel variants from 27 unreported patients. Most variants occur de novo and mainly consist of missense variants located on the voltage sensor and the pore domain of Kv 2.1. We also report the first inherited variant (p.Arg583*). KCNB1-related encephalopathies encompass a wide spectrum of neurodevelopmental disorders with predominant language difficulties and behavioral impairment. Eighty-five percent of patients developed epilepsies with variable syndromes and prognosis. Truncating variants in the C-terminal domain are associated with a less severe epileptic phenotype. Overall, this report provides an up-to-date review of the mutational and clinical spectrum of KCNB1, strengthening its place as a causal gene in DEEs and emphasizing the need for further functional studies to unravel the underlying mechanisms.
2020
Expanding the genetic and phenotypic relevance of KCNB1 variants in developmental and epileptic encephalopathies: 27 new patients and overview of the literature / Bar, C; Barcia, G; Jennesson, M; Le Guyader, G; Schneider, A; Mignot, C; Lesca, G; Breuillard, D; Montomoli, M; Keren, B; Doummar, D; de Villemeur, Tb; Afenjar, A; Marey, I; Gerard, M; Isnard, H; Poisson, A; Dupont, S; Berquin, P; Meyer, P; Genevieve, D; De Saint Martin, A; El Chehadeh, S; Chelly, J; Guët, A; Scalais, E; Dorison, N; Myers, Ct; Mefford, Hc; Howell, Kb; Marini, C; Freeman, Jl; Nica, A; Terrone, G; Sekhara, T; Lebre, As; Odent, S; Sadleir, Lg; Munnich, A; Guerrini, R; Scheffer, Ie; Kabashi, E; Nabbout, R. - In: HUMAN MUTATION. - ISSN 1059-7794. - 41:1(2020), pp. 69-80. [10.1002/humu.23915]
File in questo prodotto:
Non ci sono file associati a questo prodotto.

I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.

Utilizza questo identificativo per citare o creare un link a questo documento: https://hdl.handle.net/11588/759750
Citazioni
  • ???jsp.display-item.citation.pmc??? ND
  • Scopus 28
  • ???jsp.display-item.citation.isi??? 28
social impact