Dominant variants in major spliceosome U4 and U5 small nuclear RNA genes cause neurodevelopmental disorders through splicing disruption.
Nava C., Cogne B., Santini A., Leitão E., Lecoquierre F., Chen Y., Stenton SL., Besnard T., Heide S., Baer S., Jakhar A., Neuser S., Keren B., Faudet A., Forlani S., Faoucher M., Uguen K., Platzer K., Afenjar A., Alessandri J-L., Andres S., Angelini C., Aral B., Arveiler B., Attie-Bitach T., Aubert Mucca M., Banneau G., Barakat TS., Barcia G., Baulac S., Beneteau C., Benkerdou F., Bernard V., Bézieau S., Bonneau D., Bonnet-Dupeyron M-N., Boussion S., Boute O., Brischoux-Boucher E., Bryen SJ., Buratti J., Busa T., Caliebe A., Capri Y., Cassinari K., Caumes R., Cenni C., Chambon P., Charles P., Christodoulou J., Colson C., Conrad S., Cospain A., Coursimault J., Courtin T., Couse M., Coutton C., Creveaux I., D'Gama AM., Dauriat B., de Sainte Agathe J-M., Del Gobbo G., Delahaye-Duriez A., Delanne J., Denommé-Pichon A-S., Dieux-Coeslier A., Do Souto Ferreira L., Doco-Fenzy M., Drukewitz S., Duboc V., Dubourg C., Duffourd Y., Dyment D., El Chehadeh S., Elmaleh M., Faivre L., Fennelly S., Fischer H., Fradin M., Galludec Vaillant C., Ganne B., Ghoumid J., Goel H., Gokce-Samar Z., Goldenberg A., Gonfreville Robert R., Gorokhova S., Goujon L., Granier V., Gras M., Greally JM., Greiten B., Gueguen P., Guerrot A-M., Guha S., Guimier A., Haack TB., Hadj Abdallah H., Halleb Y., Harbuz R., Harris M., Hentschel J., Héron B., Hitz M-P., Innes AM., Jadas V., Januel L., Jean-Marçais N., Jobanputra V., Jobic F., Jornea L., Jost C., Julia S., Kaiser FJ., Kaschta D., Kaya S., Ketteler P., Khadija B., Kilpert F., Knopp C., Kraft F., Krey I., Lackmy M., Laffargue F., Lambert L., Lamont R., Laugel V., Laurie S., Lauzon JL., Lebreton L., Lebrun M., Legendre M., Leguern E., Lehalle D., Lejeune E., Lesca G., Lesieur-Sebellin M., Levy J., Linglart A., Lyonnet S., Lüthy K., Ma AS., Mach C., Mandel J-L., Mansour-Hendili L., Marcadier J., Marin V., Margot H., Marquet V., May A., Mayr JA., Meridda C., Michaud V., Michot C., Nadeau G., Naudion S., Nguyen L., Nizon M., Nowak F., Odent S., Olin V., Osei-Owusu IA., Osmond M., Õunap K., Pasquier L., Passemard S., Pauly M., Patat O., Pensec M., Perrin-Sabourin L., Petit F., Philippe C., Planes M., Poduri A., Poirsier C., Pouzet A., Prince B., Prouteau C., Pujol A., Racine C., Rama M., Ramond F., Ranguin K., Raway M., Reis A., Renaud M., Revencu N., Richard A-C., Riera-Navarro L., Rius R., Rodriguez D., Rodriguez-Palmero A., Rondeau S., Roser-Unruh A., Rougeot Jung C., Safraou H., Satre V., Saugier-Veber P., Sauvestre C., Schaefer E., Shao W., Schanze I., Schlump J-U., Schlüter Martin A., Schluth-Bolard C., Schuhmann S., Schröder C., Sebastin M., Sigaudy S., Spielmann M., Spodenkiewicz M., St Clair L., Steffann J., Stoeva R., Surowy H., Tarnopolsky MA., Todosi C., Toutain A., Tran Mau-Them F., Unterlauft A., Van-Gils J., Vanlerberghe C., Vasileiou G., Vera G., Verdel A., Verloes A., Vial Y., Vignal C., Vincent M., Vincent-Delorme C., Vincent-Devulder A., Vitobello A., Weber S., Willems M., Zaafrane-Khachnaoui K., Zacher P., Zeltner L., Ziegler A., Galej WP., Dollfus H., Thauvin C., Boycott KM., Marijon P., Lermine A., Malan V., Rio M., Kuechler A., Isidor B., Drunat S., Smol T., Chatron N., Piton A., Nicolas G., Wagner M., Abou Jamra R., Héron D., Mignot C., Blanc P., O'Donnell-Luria A., Whiffin N., Charbonnier C., Charenton C., Thevenon J., Depienne C.
The major spliceosome contains five small nuclear RNAs (snRNAs; U1, U2, U4, U5 and U6) essential for splicing. Variants in RNU4-2, encoding U4, cause a neurodevelopmental disorder called ReNU syndrome. We investigated de novo variants in 50 snRNA-encoding genes in a French cohort of 23,649 individuals with rare disorders and gathered additional cases through international collaborations. Altogether, we identified 145 previously unreported probands with (likely) pathogenic variants in RNU4-2 and 21 individuals with de novo and/or recurrent variants in RNU5B-1 and RNU5A-1, encoding U5. Pathogenic variants typically arose de novo on the maternal allele and cluster in regions critical for splicing. RNU4-2 variants mainly localize to two structures, the stem III and T-loop/quasi-pseudoknot, which position the U6 ACAGAGA box for 5' splice site recognition and associate with different phenotypic severity. RNU4-2 variants result in specific defects in alternative 5' splice site usage and methylation patterns (episignatures) that correlate with variant location and clinical severity. This study establishes RNU5B-1 as a neurodevelopmental disorder gene, suggests RNU5A-1 as a strong candidate and highlights the role of de novo variants in snRNAs.