Gene identification and functional analyses of genetically unsolved patients with neuromuscular disorders

• Applicant: Professorin Dr. Brunhilde Wirth
• Subject Area: Molecular and Cellular Neurology and Neuropathology ; Human Genetics
• Term: from 2019 to 2022
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 417989143

• Final Report Year: 2023

Final Report Abstract

5q-associated spinal muscular atrophy (SMA) is one of the most common neuromuscular disorders (NMD) and the leading hereditary cause of infant mortality. SMA without deletions or point mutations in SMN1 (non-5q SMA) is a clinically and genetically heterogeneous group of disorders and is difficult to distinguish from 5q-SMA. The disease-causing gene has been identified in approximately 45% of patients with non-5q SMA/lower motor neuron disease. Here we wanted to apply the ultimate sequencing strategies and perform trio/quattro genome sequencing (GS) and/or RNAseq along with advanced bioinformatic tools to identify the causative gene for unresolved cases where previous genetic analyses (NMD gene panel or WES) have failed. In addition, we will functionally analyse novel candidate genes for which there is strong genetic evidence of disease association. Key Results: We performed genome sequencing in 81 samples (trios/quattro in unresolved families with NMD) and 165 RNA-Seq analyses. We established 16 lymphoblastoid cell lines from blood and 25 fibroblast cell lines from skin biopsies of unresolved NMD cases and family members. We have performed extensive functional studies in two disease-causing genes, GBF1 and CAPRIN1, and in a third disease candidate gene, we have already generated mice carrying the pathogenic variants and are about to establish human inducible pluripotent stem cells using CRISPR-Cas9 genome editing technologies. These studies are still ongoing. We identified a novel mechanism using multi-omics approaches to understand the mechanism causing upregulation of Plastin3, which is a potent protective modifier for SMA but also a biomarker for cancer and osteoarthritis. This was a comprehensive and medically high-relevant project. Every new gene is deepening our knowledge on neuronal pathways/circuits and opens up new therapeutic possibilities for rare but complex and age-related neuropathies as well.

Publications

• De Novo and Inherited Variants in GBF1 are Associated with Axonal Neuropathy Caused by Golgi Fragmentation. The American Journal of Human Genetics, 107(4), 763-777.
  Mendoza-Ferreira, Natalia; Karakaya, Mert; Cengiz, Nur; Beijer, Danique; Brigatti, Karlla W.; Gonzaga-Jauregui, Claudia; Fuhrmann, Nico; Hölker, Irmgard; Thelen, Maximilian P.; Zetzsche, Sebastian; Rombo, Roman; Puffenberger, Erik G.; De Jonghe, Peter; Deconinck, Tine; Zuchner, Stephan; Strauss, Kevin A.; Carson, Vincent; Schrank, Bertold; Wunderlich, Gilbert ... & Wirth, Brunhilde
  
• Hereditary polyneuropathy with optic atrophy due to PDXK variant leading to impaired Vitamin B6 metabolism. Neuromuscular Disorders, 30(7), 583-589.
  Keller, Natalie; Mendoza-Ferreira, Natalia; Maroofian, Reza; Chelban, Viorica; Khalil, Youssef; Mills, Philippa B.; Boostani, Reza; Torbati, Paria Najarzadeh; Karimiani, Ehsan Ghayoor; Thiele, Holger; Houlden, Henry; Wirth, Brunhilde & Karakaya, Mert
  
• An ancestral 10-bp repeat expansion in VWA1 causes recessive hereditary motor neuropathy. Brain, 144(2), 584-600.
  Pagnamenta, Alistair T.; Kaiyrzhanov, Rauan; Zou, Yaqun; Da'as, Sahar I.; Maroofian, Reza; Donkervoort, Sandra; Dominik, Natalia; Lauffer, Marlen; Ferla, Matteo P.; Orioli, Andrea; Giess, Adam; Tucci, Arianna; Beetz, Christian; Sedghi, Maryam; Ansari, Behnaz; Barresi, Rita; Basiri, Keivan; Cortese, Andrea; Elgar, Greg ... & Houlden, Henry
  
• De novo DNM1L variant presenting with severe muscular atrophy, dystonia and sensory neuropathy. European Journal of Medical Genetics, 64(2), 104134.
  Keller, Natalie; Paketci, Cem; Edem, Pinar; Thiele, Holger; Yis, Uluc; Wirth, Brunhilde & Karakaya, Mert
  
• Genomic variants causing mitochondrial dysfunction are common in hereditary lower motor neuron disease. Human Mutation, 42(4), 460-472.
  Keller, Natalie; Paketci, Cem; Altmueller, Janine; Fuhrmann, Nico; Wunderlich, Gilbert; Schrank, Bertold; Unver, Olcay; Yilmaz, Sanem; Boostani, Reza; Karimiani, Ehsan Ghayoor; Motameny, Susanne; Thiele, Holger; Nürnberg, Peter; Maroofian, Reza; Yis, Uluc; Wirth, Brunhilde & Karakaya, Mert
  
• VPS13D: One Family, Same Mutations, Two Phenotypes. Movement Disorders Clinical Practice, 8(5), 803-806.
  Petry‐Schmelzer, Jan Niklas; Keller, Natalie; Karakaya, Mert; Wirth, Brunhilde; Fink, Gereon R. & Wunderlich, Gilbert
  
• CAPRIN1 haploinsufficiency causes a neurodevelopmental disorder with language impairment, ADHD and ASD. Brain, 146(2), 534-548.
  Pavinato, Lisa; Delle, Vedove Andrea; Carli, Diana; Ferrero, Marta; Carestiato, Silvia; Howe, Jennifer L.; Agolini, Emanuele; Coviello, Domenico A.; van de Laar, Ingrid; Au, Ping Yee Billie; Di Gregorio, Eleonora; Fabbiani, Alessandra; Croci, Susanna; Mencarelli, Maria Antonietta; Bruno, Lucia P.; Renieri, Alessandra; Veltra, Danai; Sofocleous, Christalena; Faivre, Laurence ... & Brusco, Alfredo
  
• CAPRIN1P512L causes aberrant protein aggregation and associates with early-onset ataxia. Cellular and Molecular Life Sciences, 79(10).
  Delle, Vedove Andrea; Natarajan, Janani; Zanni, Ginevra; Eckenweiler, Matthias; Muiños-Bühl, Anixa; Storbeck, Markus; Guillén, Boixet Jordina; Barresi, Sabina; Pizzi, Simone; Hölker, Irmgard; Körber, Friederike; Franzmann, Titus M.; Bertini, Enrico S.; Kirschner, Janbernd; Alberti, Simon; Tartaglia, Marco & Wirth, Brunhilde
  
• Epigenetic regulation of plastin 3 expression by the macrosatellite DXZ4 and the transcriptional regulator CHD4. The American Journal of Human Genetics, 110(3), 442-459.
  Strathmann, Eike A.; Hölker, Irmgard; Tschernoster, Nikolai; Hosseinibarkooie, Seyyedmohsen; Come, Julien; Martinat, Cecile; Altmüller, Janine & Wirth, Brunhilde