Syndromic disorders caused by gain-of-function variants in KCNH1, KCNK4, and KCNN3-a subgroup of K+ channelopathies

Karen W. Gripp, Sarah F. Smithson, Ingrid J. Scurr, Julia Baptista, Anirban Majumdar, Germaine Pierre, Maggie Williams, Lindsay B. Henderson, Ingrid M. Wentzensen, Heather McLaughlin, Lisette Leeuwen, Marleen E. H. Simon, Ellen van Binsbergen, Mary Beth P. Dinulos, Julie D. Kaplan, Anne McRae, Andrea Superti-Furga, Jean-Marc Good, Kerstin Kutsche*

*Bijbehorende auteur voor dit werk

    OnderzoeksoutputAcademicpeer review

    14 Citaten (Scopus)
    51 Downloads (Pure)


    Decreased or increased activity of potassium channels caused by loss-of-function and gain-of-function (GOF) variants in the corresponding genes, respectively, underlies a broad spectrum of human disorders affecting the central nervous system, heart, kidney, and other organs. While the association of epilepsy and intellectual disability (ID) with variants affecting function in genes encoding potassium channels is well known, GOF missense variants in K+ channel encoding genes in individuals with syndromic developmental disorders have only recently been recognized. These syndromic phenotypes include Zimmermann-Laband and Temple-Baraitser syndromes, caused by dominant variants in KCNH1, FHEIG syndrome due to dominant variants in KCNK4, and the clinical picture associated with dominant variants in KCNN3. Here we review the presentation of these individuals, including five newly reported with variants in KCNH1 and three additional individuals with KCNN3 variants, all variants likely affecting function. There is notable overlap in the phenotypic findings of these syndromes associated with dominant KCNN3, KCNH1, and KCNK4 variants, sharing developmental delay and/or ID, coarse facial features, gingival enlargement, distal digital hypoplasia, and hypertrichosis. We suggest to combine the phenotypes and define a new subgroup of potassium channelopathies caused by increased K+ conductance, referred to as syndromic neurodevelopmental K+ channelopathies due to dominant variants in KCNH1, KCNK4, or KCNN3.

    Originele taal-2English
    Pagina's (van-tot)1384-1395
    Aantal pagina's12
    TijdschriftEuropean Journal of Human Genetics
    Vroegere onlinedatum16-feb.-2021
    StatusPublished - sep.-2021

    Citeer dit