2018 MEETING 20-22 JUNE 2018 BOOK OF ABSTRACTS OXFORD ENCALS Meeting 2018 Acknowledgements ENCALS would like to thank the following sponsors for their generous support of this year’s meeting. Gold Sponsor Silver Sponsors Bronze Sponsors 2 ENCALS Meeting 2018 Poster Session 1: Wednesday 20th June, 18:00 - 19:30 Entrance Hall: A01 Hot-spot KIF5A mutations cause familial ALS David Brenner* (1), Rüstem Yilmaz (1), Kathrin Müller (1), Torsten Grehl (2), Susanne Petri (3), Thomas Meyer (4), Julian Grosskreutz (5), Patrick Weydt (1, 6), Wolfgang Ruf (1), Christoph Neuwirth (7), Markus Weber (7), Susana Pinto (8, 9), Kristl G. Claeys (10, 11, 12), Berthold Schrank (13), Berit Jordan (14), Antje Knehr (1), Kornelia Günther (1), Annemarie Hübers (1), Daniel Zeller (15), The German ALS network MND-NET, Christian Kubisch (16, 17), Sibylle Jablonka (18), Michael Sendtner (18), Thomas Klopstock (19), Mamede de Carvalho (8, 20), Anne Sperfeld (14), Guntram Borck (16), Alexander E. Volk (16, 17), Johannes Dorst (1), Joachim Weis (10), Markus Otto (1), Joachim Schuster (1), Kelly del Tredici (1), Heiko Braak (1), Karin M. Danzer (1), Axel Freischmidt (1), Thomas Meitinger (21), Tim M. Strom (21), Albert C. Ludolph (1), Peter M. Andersen (1, 9), and Jochen H. Weishaupt (1) Heterozygous missense mutations in the N-terminal motor or coiled-coil domains of the kinesin family member 5A (KIF5A) gene cause monogenic spastic paraplegia (HSP10) and Charcot-Marie-Tooth disease type 2 (CMT2). Moreover, heterozygous de novo frame-shift mutations in the C-terminal domain of KIF5A are associated with neonatal intractable myoclonus, a neurodevelopmental syndrome. These findings, together with the observation that many of the disease genes associated with amyotrophic lateral sclerosis disrupt cytoskeletal function and intracellular transport, led us to hypothesize that mutations in KIF5A are also a cause of amyotrophic lateral sclerosis. Using whole exome sequencing followed by rare variant analysis of 426 patients with familial amyotrophic lateral sclerosis and 6137 control subjects, we detected an enrichment of KIF5A splice-site mutations in amyotrophic lateral sclerosis (2/426 compared to 0/6137 in controls; P = 4.2 × 10−3), both located in a hot-spot in the C-terminus of the protein and predicted to affect splicing exon 27. We additionally show co-segregation with amyotrophic lateral sclerosis of two canonical splice-site mutations in two families. Investigation of lymphoblast cell lines from patients with KIF5A splice-site mutations revealed the loss of mutant RNA expression and suggested haploinsufficiency as the most probable underlying molecular mechanism. Furthermore, mRNA sequencing of a rare non-synonymous missense mutation (predicting p.Arg1007Gly) located in the C-terminus of the protein shortly upstream of the splice donor of exon 27 revealed defective KIF5A pre-mRNA splicing in respective patient-derived cell lines owing to abrogation of the donor site. Finally, the non-synonymous single nucleotide variant 3 ENCALS Meeting 2018 rs113247976 (minor allele frequency = 1.00% in controls, n = 6137), also located in the C-terminal region [p.(Pro986Leu) in exon 26], was significantly enriched in familial amyotrophic lateral sclerosis patients (minor allele frequency = 3.40%; P = 1.28 × 10−7). Our study demonstrates that mutations located specifically in a C-terminal hotspot of KIF5A can cause a classical amyotrophic lateral sclerosis phenotype, and underline the involvement of intracellular transport processes in amyotrophic lateral sclerosis pathogenesis. 1) Neurology Department, Ulm University, Ulm, Germany. 2) Department of Neurology, Alfried Krupp Hospital, Essen, Germany. 3) Department of Neurology, Hannover Medical School, Hannover, Germany. 4) Charité University Hospital, Humboldt-University, Berlin, Germany. 5) Department of Neurology, Jena University Hospital, Jena, Germany. 6) Department for Neurodegenerative Disorders and Gerontopsychiatry, Bonn University, Bonn, Germany. 7) Kantonsspital St. Gallen, ALS Outpatient Clinic, St. Gallen, Switzerland. 8) Department of Neurosciences and Mental Health, Hospital de Santa Maria-CHLN, Lisbon, Portugal. 9) Department of Pharmacology and Clinical Neuroscience, Umeå University, Umeå, Sweden. 10) Institute of Neuropathology, RWTH Aachen University Hospital, Aachen, Germany. 11) Department of Neurology, RWTH Aachen University Hospital, Aachen, Germany. 12) Department of Neurology, University Hospitals Leuven, Leuven, Belgium. Laboratory for Muscle Diseases and Neuropathies, Department of Neurosciences, Experimental Neurology, KU Leuven – University of Leuven, Leuven, Belgium. 13) Department of Neurology, DKD HELIOS Klinik Wiesbaden, Wiesbaden, Germany. 14) Department of Neurology Martin-Luther-University Halle-Wittenberg, Halle/Saale, Germany. 15) Department of Neurology, University of Würzburg, Würzburg, Germany. 16) Institute of Human Genetics, Ulm University, Ulm, Germany. 17) Institute of Human Genetics, University Medical Center Hamburg-Eppendorf, Hamburg, Germany. 18) Institute of Clinical Neurobiology, University Hospital of Würzburg, Würzburg, Germany. 19) Department of Neurology with Friedrich-Baur-Institute, University of Munich, Munich, Germany. German Center for Neurodegenerative Diseases (DZNE), Munich, Germany. Munich Cluster for Systems Neurology (SyNergy), Munich, Germany. 20) Instituto de Medicina Molecular and Institute of Physiology, Faculty of Medicine, University of Lisbon, Portugal. 21) SyNergy, Munich Cluster for Systems Neurology, Ludwig Maximilians Universität München, Germany. Institute of Human Genetics, Technische Universität München, München, Germany. 4 ENCALS Meeting 2018 A02 Alterations of C9orf72, SOD1, TARDBP, FUS and UBQLN2 genes with amyotrophic lateral sclerosis Vildan Çiftçi 1, Türker Bilgen 2, Şule Darbaş 1, Yunus Arıkan 1, Hilmi Uysal 3*, Sibel Berker Karaüzüm 1 Objective: The aim of this study is to determine existence and frequency of the genomic alterations in C9orf72, SOD1, TARDBP, FUS and UBQLN2 genes which are frequently observed in familial(fALS) and sporadic(sALS) ALS diagnosed cases. Materials-Methods: Genomic DNA was isolated from peripheral blood in 12 fALS and 18 sALS. C9orf72 gene expansion was checked by triplet-primer PCR amplification and fragment analysis. All sequences encoding the SOD1, TARDBP, FUS and UBQLN2 genes were screened by DNA sequencing. Results: In intron1 of C9orf72 gene in 2 sALS cases c.-45+162_-45+163insGGGGCC heterozygote change was detected. In SOD1 gene in 2 fALS and 5 sALS heterozygote and in 1 sALS homozygote c.72+133C>T change in intron1; in 1 fALS novel c.169+41C>A heterozygote change in intron 2; in 3 fALS c.239+34A>C heterozygote change in intron 3 was found. In intron 5 of TARDBP gene in 6 cases c.714+67_714+68insG homozygote change was detected. In FUS gene mutation screening revealed c.147C>A change in exon3 with heterozygosity in 3 sALS, in exon4 c.291C>T change with heterozygosity in 5 fALS and 8 sALS and with homozygousity in 4 fALS and 8 sALS; also in intron 11 novel c.1067-61T>C heterozygote in 3 sALS and 1 fALS. In UBQLN2 gene 1 sALS novel c.1371G>C heterozygote change was determinated. Conclusion: C9orf72 hexanucleotide repeat expansion was observed 6,6% in 32 cases as known pathogenic mutation. In this study, three novel changes have been identified. Clinical significance of these changes is not yet known. The existence of variation in FUS gene in all cases supports that this gene is highly polymorphic. Keywords: ALS, sporadic ALS, familial ALS, genomic alterations 1) Akdeniz University Faculty of Medicine, Department of Medical Biology and Genetics, Antalya 2) Namık Kemal University, Health High School, Department of Nutrition and Dietetic, Tekirdağ 3) Akdeniz University Faculty of Medicine, Department of Neurology, Antalya 5 ENCALS Meeting 2018 A03 Novel ALS-associated mutations in the ARPP21 gene cause abnormal protein aggregation and altered neuronal morphology Chun Hao Wong (1)(*), Simon D Topp (1), Youn-Bok Lee (1), Sarah Mueller (1), Graham Cocks (1), Bradley N Smith (1), Nicola Ticozzi (2), John Landers (3), Christopher E Shaw (1) Background ALS is a highly heterogeneous neurodegenerative disease in which multiple, rare genetic causes may contribute. Here, we report a new disease- associated gene ARPP21 identified through whole-exome sequencing in a cohort of familial ALS cases. Two novel variants are shared by several unrelated index cases with no mutations in currently known ALS genes. To validate the involvement of ARPP21 in ALS, we have screened the gene extensively and studied the identified variants in cellular models. Materials and Methods Direct sequencing was performed on over 2000 ALS cases and 1000 controls of UK, US and Italian origin. Disease modelling was performed in HEK239T, SH-SY5Y and primary rat cortical neurons. Results Both variants linked with familial ALS (p.P563L; p.P747L) are replicated in a sporadic ALS cohort. The p.Proline563 residue is found to be substituted to glutamine in two sporadic cases of UK and Italian origin. These mutations are absent in both public databases and local control cohorts. Immunohistochemistry against the endogenous ARPP21 protein in human post-mortem cerebellum and spinal cord tissues suggests that it is a predominantly cytosolic phosphoprotein that is highly enriched in the neuronal population. Functional assays indicate that the ALS-associated mutations could cause disease hallmarks including enhanced detergent-insoluble aggregates, dysregulation