@article {918, title = {De novo variants in SNAP25 cause an early-onset developmental and epileptic encephalopathy.}, journal = {Genet Med}, volume = {23}, year = {2021}, month = {2021 04}, pages = {653-660}, abstract = {

PURPOSE: This study aims to provide a comprehensive description of the phenotypic and genotypic spectrum of SNAP25 developmental and epileptic encephalopathy (SNAP25-DEE) by reviewing newly identified and previously reported individuals.

METHODS: Individuals harboring heterozygous missense or loss-of-function variants in SNAP25 were assembled through collaboration with international colleagues, matchmaking platforms, and literature review. For each individual, detailed phenotyping, classification, and structural modeling of the identified variant were performed.

RESULTS: The cohort comprises 23 individuals with pathogenic or likely pathogenic de novo variants in SNAP25. Intellectual disability and early-onset epilepsy were identified as the core symptoms of SNAP25-DEE, with recurrent findings of movement disorders, cerebral visual impairment, and brain atrophy. Structural modeling for all variants predicted possible functional defects concerning SNAP25 or impaired interaction with other components of the SNARE complex.

CONCLUSION: We provide a comprehensive description of SNAP25-DEE with intellectual disability and early-onset epilepsy mostly occurring before the age of two years. These core symptoms and additional recurrent phenotypes show an overlap to genes encoding other components or associated proteins of the SNARE complex such as STX1B, STXBP1, or VAMP2. Thus, these findings advance the concept of a group of neurodevelopmental disorders that may be termed "SNAREopathies."

}, keywords = {Brain Diseases, Child, Preschool, Epilepsy, Humans, Intellectual Disability, Neurodevelopmental Disorders, Phenotype, Synaptosomal-Associated Protein 25}, issn = {1530-0366}, doi = {10.1038/s41436-020-01020-w}, author = {Kl{\"o}ckner, Chiara and Sticht, Heinrich and Zacher, Pia and Popp, Bernt and Babcock, Holly E and Bakker, Dewi P and Barwick, Katy and Bonfert, Michaela V and B{\"o}nnemann, Carsten G and Brilstra, Eva H and Chung, Wendy K and Clarke, Angus J and Devine, Patrick and Donkervoort, Sandra and Fraser, Jamie L and Friedman, Jennifer and Gates, Alyssa and Ghoumid, Jamal and Hobson, Emma and Horvath, Gabriella and Keller-Ramey, Jennifer and Keren, Boris and Kurian, Manju A and Lee, Virgina and Leppig, Kathleen A and Lundgren, Johan and McDonald, Marie T and McLaughlin, Heather M and McTague, Amy and Mefford, Heather C and Mignot, Cyril and Mikati, Mohamad A and Nava, Caroline and Raymond, F Lucy and Sampson, Julian R and Sanchis-Juan, Alba and Shashi, Vandana and Shieh, Joseph T C and Shinawi, Marwan and Slavotinek, Anne and St{\"o}dberg, Tommy and Stong, Nicholas and Sullivan, Jennifer A and Taylor, Ashley C and Toler, Tomi L and van den Boogaard, Marie-Jos{\'e} and van der Crabben, Saskia N and van Gassen, Koen L I and van Jaarsveld, Richard H and Van Ziffle, Jessica and Wadley, Alexandrea F and Wagner, Matias and Wigby, Kristen and Wortmann, Saskia B and Zarate, Yuri A and M{\o}ller, Rikke S and Lemke, Johannes R and Platzer, Konrad} } @article {670, title = {CTCF variants in 39 individuals with a variable neurodevelopmental disorder broaden the mutational and clinical spectrum.}, journal = {Genet Med}, volume = {21}, year = {2019}, month = {2019 12}, pages = {2723-2733}, abstract = {

PURPOSE: Pathogenic variants in the chromatin organizer CTCF were previously reported in seven individuals with a neurodevelopmental disorder (NDD).

METHODS: Through international collaboration we collected data from 39 subjects with variants in CTCF. We performed transcriptome analysis on RNA from blood samples and utilized Drosophila melanogaster to investigate the impact of Ctcf dosage alteration on nervous system development and function.

RESULTS: The individuals in our cohort carried 2 deletions, 8 likely gene-disruptive, 2 splice-site, and 20 different missense variants, most of them de novo. Two cases were familial. The associated phenotype was of variable severity extending from mild developmental delay or normal IQ to severe intellectual disability. Feeding difficulties and behavioral abnormalities were common, and variable other findings including growth restriction and cardiac defects were observed. RNA-sequencing in five individuals identified 3828 deregulated genes enriched for known NDD genes and biological processes such as transcriptional regulation. Ctcf dosage alteration in Drosophila resulted in impaired gross neurological functioning and learning and memory deficits.

CONCLUSION: We significantly broaden the mutational and clinical spectrum ofCTCF-associated NDDs. Our data shed light onto the functional role of CTCF by identifying deregulated genes and show that Ctcf alterations result in nervous system defects in Drosophila.

}, issn = {1530-0366}, doi = {10.1038/s41436-019-0585-z}, author = {Konrad, Enrico D H and Nardini, Niels and Caliebe, Almuth and Nagel, Inga and Young, Dana and Horvath, Gabriella and Santoro, Stephanie L and Shuss, Christine and Ziegler, Alban and Bonneau, Dominique and Kempers, Marlies and Pfundt, Rolph and Legius, Eric and Bouman, Arjan and Stuurman, Kyra E and {\~O}unap, Katrin and Pajusalu, Sander and Wojcik, Monica H and Vasileiou, Georgia and Le Guyader, Gwena{\"e}l and Schnelle, Hege M and Berland, Siren and Zonneveld-Huijssoon, Evelien and Kersten, Simone and Gupta, Aditi and Blackburn, Patrick R and Ellingson, Marissa S and Ferber, Matthew J and Dhamija, Radhika and Klee, Eric W and McEntagart, Meriel and Lichtenbelt, Klaske D and Kenney, Amy and Vergano, Samantha A and Abou Jamra, Rami and Platzer, Konrad and Ella Pierpont, Mary and Khattar, Divya and Hopkin, Robert J and Martin, Richard J and Jongmans, Marjolijn C J and Chang, Vivian Y and Martinez-Agosto, Julian A and Kuismin, Outi and Kurki, Mitja I and Pietil{\"a}inen, Olli and Palotie, Aarno and Maarup, Timothy J and Johnson, Diana S and Venborg Pedersen, Katja and Laulund, Lone W and Lynch, Sally A and Blyth, Moira and Prescott, Katrina and Canham, Natalie and Ibitoye, Rita and Brilstra, Eva H and Shinawi, Marwan and Fassi, Emily and Sticht, Heinrich and Gregor, Anne and Van Esch, Hilde and Zweier, Christiane} } @article {594, title = {Spatially clustering de novo variants in CYFIP2, encoding the cytoplasmic FMRP interacting protein 2, cause intellectual disability and seizures.}, journal = {Eur J Hum Genet}, volume = {27}, year = {2019}, month = {2019 May}, pages = {747-759}, abstract = {

CYFIP2, encoding the evolutionary highly conserved cytoplasmic FMRP interacting protein 2, has previously been proposed as a candidate gene for intellectual disability and autism because of its important role linking FMRP-dependent transcription regulation and actin polymerization via the WAVE regulatory complex (WRC). Recently, de novo variants affecting the amino acid p.Arg87 of CYFIP2 were reported in four individuals with epileptic encephalopathy. We here report 12 independent patients harboring a variety of de novo variants in CYFIP2 broadening the molecular and clinical spectrum of a novel CYFIP2-related neurodevelopmental disorder. Using trio whole-exome or -genome sequencing, we identified 12 independent patients carrying a total of eight distinct de novo variants in CYFIP2 with a shared phenotype of intellectual disability, seizures, and muscular hypotonia. We detected seven different missense variants, of which two occurred recurrently (p.(Arg87Cys) and p.(Ile664Met)), and a splice donor variant in the last intron for which we showed exon skipping in the transcript. The latter is expected to escape nonsense-mediated mRNA decay resulting in a truncated protein. Despite the large spacing in the primary structure, the variants spatially cluster in the tertiary structure and are all predicted to weaken the interaction with WAVE1 or NCKAP1 of the actin polymerization regulating WRC-complex. Preliminary genotype-phenotype correlation indicates a profound phenotype in p.Arg87 substitutions and a more variable phenotype in other alterations. This study evidenced a variety of de novo variants in CYFIP2 as a novel cause of mostly severe intellectual disability with seizures and muscular hypotonia.

}, issn = {1476-5438}, doi = {10.1038/s41431-018-0331-z}, author = {Zweier, Markus and Begemann, Ana{\"\i}s and McWalter, Kirsty and Cho, Megan T and Abela, Lucia and Banka, Siddharth and Behring, Bettina and Berger, Andrea and Brown, Chester W and Carneiro, Maryline and Chen, Jiani and Cooper, Gregory M and Finnila, Candice R and Guillen Sacoto, Maria J and Henderson, Alex and H{\"u}ffmeier, Ulrike and Joset, Pascal and Kerr, Bronwyn and Lesca, Gaetan and Leszinski, Gloria S and McDermott, John Henry and Meltzer, Meira R and Monaghan, Kristin G and Mostafavi, Roya and {\~O}unap, Katrin and Plecko, Barbara and Powis, Z{\"o}e and Purcarin, Gabriela and Reimand, Tiia and Riedhammer, Korbinian M and Schreiber, John M and Sirsi, Deepa and Wierenga, Klaas J and Wojcik, Monica H and Papuc, Sorina M and Steindl, Katharina and Sticht, Heinrich and Rauch, Anita} } @article {483, title = {De Novo Variants in the F-Box Protein FBXO11 in 20 Individuals with a Variable Neurodevelopmental Disorder.}, journal = {Am J Hum Genet}, volume = {103}, year = {2018}, month = {2018 08 02}, pages = {305-316}, abstract = {

Next-generation sequencing combined with international data sharing has enormously facilitated identification of new disease-associated genes and mutations. This is particularly true for genetically extremely heterogeneous entities such as neurodevelopmental disorders (NDDs). Through exome sequencing and world-wide collaborations, we identified and assembled 20 individuals with de novo variants in FBXO11. They present with mild to severe developmental delay associated with a range of features including short (4/20) or tall (2/20) stature, obesity (5/20), microcephaly (4/19) or macrocephaly (2/19), behavioral problems (17/20), seizures (5/20), cleft lip or palate or bifid uvula (3/20), and minor skeletal anomalies. FBXO11 encodes a member of the F-Box protein family, constituting a subunit of an E3-ubiquitin ligase complex. This complex is involved in ubiquitination and proteasomal degradation and thus in controlling critical biological processes by regulating protein turnover. The identified de novo aberrations comprise two large deletions, ten likely gene disrupting variants, and eight missense variants distributed throughout FBXO11. Structural modeling for missense variants located in the CASH or the Zinc-finger UBR domains suggests destabilization of the protein. This, in combination with the observed spectrum and localization of identified variants and the lack of apparent genotype-phenotype correlations, is compatible with loss of function or haploinsufficiency as an underlying mechanism. We implicate de novo missense and likely gene disrupting variants in FBXO11 in a neurodevelopmental disorder with variable intellectual disability and various other features.

}, issn = {1537-6605}, doi = {10.1016/j.ajhg.2018.07.003}, author = {Gregor, Anne and Sadleir, Lynette G and Asadollahi, Reza and Azzarello-Burri, Silvia and Battaglia, Agatino and Ousager, Lilian Bomme and Boonsawat, Paranchai and Bruel, Ange-Line and Buchert, Rebecca and Calpena, Eduardo and Cogn{\'e}, Benjamin and Dallapiccola, Bruno and Distelmaier, Felix and Elmslie, Frances and Faivre, Laurence and Haack, Tobias B and Harrison, Victoria and Henderson, Alex and Hunt, David and Isidor, Bertrand and Joset, Pascal and Kumada, Satoko and Lachmeijer, Augusta M A and Lees, Melissa and Lynch, Sally Ann and Martinez, Francisco and Matsumoto, Naomichi and McDougall, Carey and Mefford, Heather C and Miyake, Noriko and Myers, Candace T and Moutton, S{\'e}bastien and Nesbitt, Addie and Novelli, Antonio and Orellana, Carmen and Rauch, Anita and Rosello, Monica and Saida, Ken and Santani, Avni B and Sarkar, Ajoy and Scheffer, Ingrid E and Shinawi, Marwan and Steindl, Katharina and Symonds, Joseph D and Zackai, Elaine H and Reis, Andr{\'e} and Sticht, Heinrich and Zweier, Christiane} }