1. Genotype-phenotype correlations in SCN8A-related disorders reveal prognostic and therapeutic implications
- Author
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Luxembourg Centre for Systems Biomedicine (LCSB): Bioinformatics Core (R. Schneider Group) [research center], BMBF, Treat-ION, 01GM1907 [sponsor], Johannesen, Katrine M., Liu, Yuanyuan, Koko, Mahmoud, Gjerulfsen, Cathrine E., Sonnenberg, Lukas, Schubert, Julian, Fenger, Christina D., Eltokhi, Ahmed, Rannap, Maert, Koch, Nils A., Lauxmann, Stephan, Krüger, Johanna, Kegele, Josua, Canafoglia, Laura, Franceschetti, Silvana, Mayer, Thomas, Rebstock, Johannes, Zacher, Pia, Ruf, Susanne, Alber, Michael, Sterbova, Katalin, Lassuthová, Petra, Vlckova, Marketa, Lemke, Johannes R., Platzer, Konrad, Krey, Ilona, Heine, Constanze, Wieczorek, Dagmar, Kroell-Seger, Judith, Lund, Caroline, Klein, Karl Martin, Billie Au, P. Y., Rho, Jong M., Ho, Alice W., Masnada, Silvia, Veggiotti, Pierangelo, Giordano, Lucio, Accorsi, Patrizia, Hoei-Hansen, Christina E., Striano, Pasquale, Zara, Federico, Verhelst, Helene, Verhoeven, Judith S., van der Zwaag, Bert, Harder, Aster V. E., Brilstra, Eva, Pendziwiat, Manuela, Lebon, Sebastian, Vaccarezza, Maria, Minh Le, Ngoc, Christensen, Jakob, Grønborg, Sabine, Scherer, Stephen W., Howe, Jennifer, Fazeli, Walid, Howell, Katherine B., Leventer, Richard, Stutterd, Chloe, Walsh, Sonja, Gerard, Marion, Gerard, Bénédicte, Matricardi, Sara, Bonardi, Claudia M., Sartori, Stefano, Berger, Andrea, Hoffman-Zacharska, Dorota, Mastrangelo, Massimo, Darra, Francesca, Vøllo, Arve, Motazacker, M. Mahdi, Lakeman, Phillis, Nizon, Mathilde, Betzler, Cornelia, Altuzarra, Cecilia, Caume, Roseline, Roubertie, Agathe, Gélisse, Philippe, Marini, Carla, Guerrini, Renzo, Bilan, Frederic, Tibussek, Daniel, Koch-Hogrebe, Margarete, Perry, M. Scott, Ichikawa, Shoji, Dadali, Elena, Sharkov, Artem, Mishina, Irina, Abramov, Mikhail, Kanivets, Ilya, Korostelev, Sergey, Kutsev, Sergey, Wain, Karen E., Eisenhauer, Nancy, Wagner, Monisa, Savatt, Juliann M., Müller-Schlüter, Karen, Bassan, Haim, Borovikov, Artem, Nassogne, Marie-Cecile, Destrée, Anne, Schoonjans, An-Sofie, Meuwissen, Marije, Buzatu, Marga, Jansen, Anna, Scalais, Emmanuel, Srivastava, Siddharth, Tan, Wen-Hann, Olson, Heather E., Loddenkemper, Tobias, Poduri, Annapurna, Helbig, Katherine L., Helbig, Ingo, Fitzgerald, Mark P., Goldberg, Ethan M., Roser, Timo, Borggraefe, Ingo, Brünger, Tobias, May, Patrick, Lal, Dennis, Lederer, Damien, Rubboli, Guido, Heyne, Henrike O., Lesca, Gaetan, Hedrich, Ulrike B. S., Benda, Jan, Gardella, Elena, Lerche, Holger, Møller, Rikke S., Luxembourg Centre for Systems Biomedicine (LCSB): Bioinformatics Core (R. Schneider Group) [research center], BMBF, Treat-ION, 01GM1907 [sponsor], Johannesen, Katrine M., Liu, Yuanyuan, Koko, Mahmoud, Gjerulfsen, Cathrine E., Sonnenberg, Lukas, Schubert, Julian, Fenger, Christina D., Eltokhi, Ahmed, Rannap, Maert, Koch, Nils A., Lauxmann, Stephan, Krüger, Johanna, Kegele, Josua, Canafoglia, Laura, Franceschetti, Silvana, Mayer, Thomas, Rebstock, Johannes, Zacher, Pia, Ruf, Susanne, Alber, Michael, Sterbova, Katalin, Lassuthová, Petra, Vlckova, Marketa, Lemke, Johannes R., Platzer, Konrad, Krey, Ilona, Heine, Constanze, Wieczorek, Dagmar, Kroell-Seger, Judith, Lund, Caroline, Klein, Karl Martin, Billie Au, P. Y., Rho, Jong M., Ho, Alice W., Masnada, Silvia, Veggiotti, Pierangelo, Giordano, Lucio, Accorsi, Patrizia, Hoei-Hansen, Christina E., Striano, Pasquale, Zara, Federico, Verhelst, Helene, Verhoeven, Judith S., van der Zwaag, Bert, Harder, Aster V. E., Brilstra, Eva, Pendziwiat, Manuela, Lebon, Sebastian, Vaccarezza, Maria, Minh Le, Ngoc, Christensen, Jakob, Grønborg, Sabine, Scherer, Stephen W., Howe, Jennifer, Fazeli, Walid, Howell, Katherine B., Leventer, Richard, Stutterd, Chloe, Walsh, Sonja, Gerard, Marion, Gerard, Bénédicte, Matricardi, Sara, Bonardi, Claudia M., Sartori, Stefano, Berger, Andrea, Hoffman-Zacharska, Dorota, Mastrangelo, Massimo, Darra, Francesca, Vøllo, Arve, Motazacker, M. Mahdi, Lakeman, Phillis, Nizon, Mathilde, Betzler, Cornelia, Altuzarra, Cecilia, Caume, Roseline, Roubertie, Agathe, Gélisse, Philippe, Marini, Carla, Guerrini, Renzo, Bilan, Frederic, Tibussek, Daniel, Koch-Hogrebe, Margarete, Perry, M. Scott, Ichikawa, Shoji, Dadali, Elena, Sharkov, Artem, Mishina, Irina, Abramov, Mikhail, Kanivets, Ilya, Korostelev, Sergey, Kutsev, Sergey, Wain, Karen E., Eisenhauer, Nancy, Wagner, Monisa, Savatt, Juliann M., Müller-Schlüter, Karen, Bassan, Haim, Borovikov, Artem, Nassogne, Marie-Cecile, Destrée, Anne, Schoonjans, An-Sofie, Meuwissen, Marije, Buzatu, Marga, Jansen, Anna, Scalais, Emmanuel, Srivastava, Siddharth, Tan, Wen-Hann, Olson, Heather E., Loddenkemper, Tobias, Poduri, Annapurna, Helbig, Katherine L., Helbig, Ingo, Fitzgerald, Mark P., Goldberg, Ethan M., Roser, Timo, Borggraefe, Ingo, Brünger, Tobias, May, Patrick, Lal, Dennis, Lederer, Damien, Rubboli, Guido, Heyne, Henrike O., Lesca, Gaetan, Hedrich, Ulrike B. S., Benda, Jan, Gardella, Elena, Lerche, Holger, and Møller, Rikke S.
- Abstract
We report detailed functional analyses and genotype-phenotype correlations in 392 individuals carrying disease-causing variants in SCN8A, encoding the voltage-gated Na+ channel NaV1.6, with the aim of describing clinical phenotypes related to functional effects. Six different clinical subgroups could be identified: 1) Benign familial infantile epilepsy (BFIE) (n = 15, normal cognition, treatable seizures), 2) intermediate epilepsy (n = 33, mild ID, partially pharmaco-responsive), 3) developmental and epileptic encephalopathy (DEE, n = 177, severe ID, majority pharmaco-resistant), 4) generalized epilepsy (n = 20, mild to moderate ID, frequently with absence seizures), 5) unclassifiable epilepsy (n = 127), and 6) neurodevelopmental disorder without epilepsy (n = 20, mild to moderate ID). Groups 1–3 presented with focal or multifocal seizures (median age of onset: four months) and focal epileptiform discharges, whereas the onset of seizures in group 4 was later (median: 42 months) with generalized epileptiform discharges. We performed functional studies expressing missense variants in ND7/23 neuroblastoma cells and primary neuronal cultures using recombinant tetrodotoxin-insensitive human NaV1.6 channels and whole-cell patch-clamping. Two variants causing DEE showed a strong gain-of-function (GOF, hyperpolarising shift of steady-state activation, strongly increased neuronal firing rate), and one variant causing BFIE or intermediate epilepsy showed a mild GOF (defective fast inactivation, less increased firing). In contrast, all three variants causing generalized epilepsy induced a loss-of-function (LOF, reduced current amplitudes, depolarising shift of steady-state activation, reduced neuronal firing). Including previous studies, functional effects were known for 170 individuals. All 136 individuals carrying a functionally tested GOF variant had either focal (97, groups 1–3), or unclassifiable epilepsy (39), whereas 34 with a LOF variant had either generalized (14), no
- Published
- 2022