Browsing by Author "Faivre, Laurence"

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    Missense variants in ANKRD11 cause KBG syndrome by impairment of stability or transcriptional activity of the encoded protein
    (Elsevier, 2022-10) de Boer, Elke; Ockeloen, Charlotte W.; Kampen, Rosalie A.; Hampstead, Juliet E.; Dingemans, Alexander J. M.; Rots, Dmitrijs; Lütje, Lukas; Ashraf, Tazeen; Baker, Rachel; Barat-Houari, Mouna; Angle, Brad; Chatron, Nicolas; Denommé-Pichon, Anne-Sophie; Devinsky, Orrin; Dubourg, Christèle; Elmslie, Frances; Elloumi, Houda Zghal; Faivre, Laurence; Fitzgerald-Butt, Sarah; Geneviève, David; Goos, Jacqueline A. C.; Helm, Benjamin M.; Kini, Usha; Lasa-Aranzasti, Amaia; Lesca, Gaetan; Lynch, Sally A.; Mathijssen, Irene M. J.; McGowan, Ruth; Monaghan, Kristin G.; Odent, Syvie; Pfundt, Rolph; Putoux, Audrey; van Reeuwijk, Jeroen; Santen, Gijs W. E.; Sasaki, Erina; Sorlin, Arthur; van der Spek, Peter J.; Stegmann, Alexander P. A.; Swagemakers, Sigrid M. A.; Valenzuela, Irene; Viora-Dupont, Eléonore; Vitobello, Antonio; Ware, Stephanie M.; Wéber, Mathys; Gilissen, Christian; Low, Karen J.; Fisher, Simon E.; Vissers, Lisenka E. L. M.; Wong, Maggie M. K.; Kleefstra, Tjitske; Pediatrics, School of Medicine
    Purpose Although haploinsufficiency of ANKRD11 is among the most common genetic causes of neurodevelopmental disorders, the role of rare ANKRD11 missense variation remains unclear. We characterized clinical, molecular, and functional spectra of ANKRD11 missense variants. Methods We collected clinical information of individuals with ANKRD11 missense variants and evaluated phenotypic fit to KBG syndrome. We assessed pathogenicity of variants through in silico analyses and cell-based experiments. Results We identified 20 unique, mostly de novo, ANKRD11 missense variants in 29 individuals, presenting with syndromic neurodevelopmental disorders similar to KBG syndrome caused by ANKRD11 protein truncating variants or 16q24.3 microdeletions. Missense variants significantly clustered in repression domain 2 at the ANKRD11 C-terminus. Of the 10 functionally studied missense variants, 6 reduced ANKRD11 stability. One variant caused decreased proteasome degradation and loss of ANKRD11 transcriptional activity. Conclusion Our study indicates that pathogenic heterozygous ANKRD11 missense variants cause the clinically recognizable KBG syndrome. Disrupted transrepression capacity and reduced protein stability each independently lead to ANKRD11 loss-of-function, consistent with haploinsufficiency. This highlights the diagnostic relevance of ANKRD11 missense variants, but also poses diagnostic challenges because the KBG-associated phenotype may be mild and inherited pathogenic ANKRD11 (missense) variants are increasingly observed, warranting stringent variant classification and careful phenotyping.
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    Missense variants in TAF1 and developmental phenotypes: Challenges of determining pathogenicity
    (Wiley, 2019-10-23) Cheng, Hanyin; Capponi, Simona; Wakeling, Emma; Marchi, Elaine; Li, Quan; Zhao, Mengge; Weng, Chunhua; Piatek, Stefan G.; Ahlfors, Helena; Kleyner, Robert; Rope, Alan; Lumaka, Aimé; Lukusa, Prosper; Devriendt, Koenraad; Vermeesch, Joris; Posey, Jennifer E.; Palmer, Elizabeth E.; Murray, Lucinda; Leon, Eyby; Diaz, Jullianne; Worgan, Lisa; Mallawaarachchi, Amali; Vogt, Julie; de Munnik, Sonja A.; Dreyer, Lauren; Baynam, Gareth; Ewans, Lisa; Stark, Zornitza; Lunke, Sebastian; Gonçalves, Ana R.; Soares, Gabriela; Oliveira, Jorge; Fassi, Emily; Willing, Marcia; Waugh, Jeff L.; Faivre, Laurence; Riviere, Jean-Baptiste; Moutton, Sebastien; Mohammed, Shehla; Payne, Katelyn; Walsh, Laurence; Begtrup, Amber; Guillen Sacoto, Maria J.; Douglas, Ganka; Alexander, Nora; Buckley, Michael F.; Mark, Paul R.; Adès, Lesley C.; Sandaradura, Sarah A.; Lupski, James R.; Roscioli, Tony; Agrawal, Pankaj B.; Kline, Antonie D.; Wang, Kai; Timmers, T. Marc; Lyon, Gholson J.; Neurology, School of Medicine
    We recently described a new neurodevelopmental syndrome (TAF1/MRXS33 intellectual disability syndrome) (MIM# 300966) caused by pathogenic variants involving the X-linked gene TAF1, which participates in RNA polymerase II transcription. The initial study reported eleven families, and the syndrome was defined as presenting early in life with hypotonia, facial dysmorphia, and developmental delay that evolved into intellectual disability (ID) and/or autism spectrum disorder (ASD). We have now identified an additional 27 families through a genotype-first approach. Familial segregation analysis, clinical phenotyping, and bioinformatics were capitalized on to assess potential variant pathogenicity, and molecular modelling was performed for those variants falling within structurally characterized domains of TAF1. A novel phenotypic clustering approach was also applied, in which the phenotypes of affected individuals were classified using 51 standardized Human Phenotype Ontology (HPO) terms. Phenotypes associated with TAF1 variants show considerable pleiotropy and clinical variability, but prominent among previously unreported effects were brain morphological abnormalities, seizures, hearing loss, and heart malformations. Our allelic series broadens the phenotypic spectrum of TAF1/MRXS33 intellectual disability syndrome and the range of TAF1 molecular defects in humans. It also illustrates the challenges for determining the pathogenicity of inherited missense variants, particularly for genes mapping to chromosome X.
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    Rare deleterious mutations of HNRNP genes result in shared neurodevelopmental disorders
    (BMC, 2021-04-19) Gillentine, Madelyn A.; Wang, Tianyun; Hoekzema, Kendra; Rosenfeld, Jill; Liu, Pengfei; Guo, Hui; Kim, Chang N.; De Vries, Bert B.A.; Vissers, Lisenka E.L.M.; Nordenskjold, Magnus; Kvarnung, Malin; Lindstrand, Anna; Nordgren, Ann; Gecz, Jozef; Iascone, Maria; Cereda, Anna; Scatigno, Agnese; Maitz, Silvia; Zanni, Ginevra; Bertini, Enrico; Zweier, Christiane; Schuhmann, Sarah; Wiesener, Antje; Pepper, Micah; Panjwani, Heena; Torti, Erin; Abid, Farida; Anselm, Irina; Srivastava, Siddharth; Atwal, Paldeep; Bacino, Carlos A.; Bhat, Gifty; Cobian, Katherine; Bird, Lynne M.; Friedman, Jennifer; Wright, Meredith S.; Callewaert, Bert; Petit, Florence; Mathieu, Sophie; Afenjar, Alexandra; Christensen, Celenie K.; White, Kerry M.; Elpeleg, Orly; Berger, Itai; Espineli, Edward J.; Fagerberg, Christina; Brasch-Andersen, Charlotte; Hansen, Lars Kjærsgaard; Feyma, Timothy; Hughes, Susan; Thiffault, Isabelle; Sullivan, Bonnie; Yan, Shuang; Keller, Kory; Keren, Boris; Mignot, Cyril; Kooy, Frank; Meuwissen, Marije; Basinger, Alice; Kukolich, Mary; Philips, Meredith; Ortega, Lucia; Drummond-Borg, Margaret; Lauridsen, Mathilde; Sorensen, Kristina; Lehman, Anna; Lopez-Range, Elena; Levy, Paul; Lessel, Davor; Lotze, Timothy; Madan-Khetarpal, Suneeta; Sebastian, Jessica; Vento, Jodie; Vats, Divya; Benman, L. Manace; Mckee, Shane; Mirzaa, Ghayda M.; Muss, Candace; Pappas, John; Peeters, Hilde; Romano, Corrado; Elia, Maurizio; Galesi, Ornella; Simon, Marleen E.H.; Van Gassen, Koen L.I.; Simpson, Kara; Stratton, Robert; Syed, Sabeen; Thevenon, Julien; Palafoll, Irene Valenzuela; Vitobello, Antonio; Bournez, Marie; Faivre, Laurence; Xia, Kun; Earl, Rachel K.; Nowakowski, Tomasz; Bernier, Raphael A.; Eichler, Evan E.; Pediatrics, School of Medicine
    Background: With the increasing number of genomic sequencing studies, hundreds of genes have been implicated in neurodevelopmental disorders (NDDs). The rate of gene discovery far outpaces our understanding of genotype-phenotype correlations, with clinical characterization remaining a bottleneck for understanding NDDs. Most disease-associated Mendelian genes are members of gene families, and we hypothesize that those with related molecular function share clinical presentations. Methods: We tested our hypothesis by considering gene families that have multiple members with an enrichment of de novo variants among NDDs, as determined by previous meta-analyses. One of these gene families is the heterogeneous nuclear ribonucleoproteins (hnRNPs), which has 33 members, five of which have been recently identified as NDD genes (HNRNPK, HNRNPU, HNRNPH1, HNRNPH2, and HNRNPR) and two of which have significant enrichment in our previous meta-analysis of probands with NDDs (HNRNPU and SYNCRIP). Utilizing protein homology, mutation analyses, gene expression analyses, and phenotypic characterization, we provide evidence for variation in 12 HNRNP genes as candidates for NDDs. Seven are potentially novel while the remaining genes in the family likely do not significantly contribute to NDD risk. Results: We report 119 new NDD cases (64 de novo variants) through sequencing and international collaborations and combined with published clinical case reports. We consider 235 cases with gene-disruptive single-nucleotide variants or indels and 15 cases with small copy number variants. Three hnRNP-encoding genes reach nominal or exome-wide significance for de novo variant enrichment, while nine are candidates for pathogenic mutations. Comparison of HNRNP gene expression shows a pattern consistent with a role in cerebral cortical development with enriched expression among radial glial progenitors. Clinical assessment of probands (n = 188-221) expands the phenotypes associated with HNRNP rare variants, and phenotypes associated with variation in the HNRNP genes distinguishes them as a subgroup of NDDs. Conclusions: Overall, our novel approach of exploiting gene families in NDDs identifies new HNRNP-related disorders, expands the phenotypes of known HNRNP-related disorders, strongly implicates disruption of the hnRNPs as a whole in NDDs, and supports that NDD subtypes likely have shared molecular pathogenesis. To date, this is the first study to identify novel genetic disorders based on the presence of disorders in related genes. We also perform the first phenotypic analyses focusing on related genes. Finally, we show that radial glial expression of these genes is likely critical during neurodevelopment. This is important for diagnostics, as well as developing strategies to best study these genes for the development of therapeutics.