Multiorgan manifestations of COL4A1 and COL4A2 variants and proposal for a clinical management protocol Simone Gasparini, Simona Balestrini, Luigi Francesco Saccaro, Giacomo Bacci, Giorgia Panichella, Martino Montomoli, Gaetano Cantalupo, Stefania Bigoni, Giorgia Mancano, Simona Pellacani, Vincenzo Leuzzi, Nila Volpi, Francesco Mari, Federico Melani, Mara Cavallin, Tiziana Pisano, Giulio Porcedda, Augusto Vaglio, Davide Mei, Carmen Barba, Elena Parrini, Renzo Guerrini American Journal of Medical Genetics Part C Seminars in Medical Genetics, 2024 COL4A1/2 variants are associated with highly variable multiorgan manifestations. Depicting the whole clinical spectrum of COL4A1/2‐related manifestations is challenging, and there is no consensus on management and preventative strategies. Based on a systematic review of current evidence on COL4A1/2‐related disease, we developed a clinical questionnaire that we administered to 43 individuals from 23 distinct families carrying pathogenic variants. In this cohort, we extended ophthalmological and cardiological examinations to asymptomatic individuals and those with only limited or mild, often nonspecific, clinical signs commonly occurring in the general population (i.e., oligosymptomatic). The most frequent clinical findings emerging from both the literature review and the questionnaire included stroke (203/685, 29.6%), seizures or epilepsy (199/685, 29.0%), intellectual disability or developmental delay (168/685, 24.5%), porencephaly/schizencephaly (168/685, 24.5%), motor impairment (162/685, 23.6%), cataract (124/685, 18.1%), hematuria (63/685, 9.2%), and retinal arterial tortuosity (58/685, 8.5%). In oligosymptomatic and asymptomatic carriers, ophthalmological investigations detected retinal vascular tortuosity (5/13, 38.5%), dysgenesis of the anterior segment (4/13, 30.8%), and cataract (2/13, 15.4%), while cardiological investigations were unremarkable except for mild ascending aortic ectasia in 1/8 (12.5%). Our multimodal approach confirms highly variable penetrance and expressivity in COL4A1/2‐related conditions, even at the intrafamilial level with neurological involvement being the most frequent and severe finding in both children and adults. We propose a protocol for prevention and management based on individualized risk estimation and periodic multiorgan evaluations.
Generation of a human induced pluripotent stem cell line from a patient with GM3 synthase deficiency using self-replicating RNA vector Rodolfo Tonin, Federica Feo, Silvia Falliano, Laura Giunti, Martino Calamai, Elena Procopio, Francesco Mari, Vittorio Sciruicchio, Valerio Conti, Ilaria Fanelli, Franco Bambi, Renzo Guerrini, Amelia Morrone Stem Cell Research, 2024 GM3 synthase deficiency (GM3SD) is caused by biallelic variants in the ST3GAL5 gene. Early clinical features of GM3SD include infantile onset of severe irritability and feeding difficulties, early intractable seizures, growth failure, hypotonia, sensorineural hearing impairment. We describe the generation and characterization the human induced pluripotent stem cell (hiPSC) line derived from fibroblasts of a 13-year-old girl with GM3 synthase deficiency resulted compound heterozygous for two new variants in the ST3GAL5 gene, c.1166A > G (p.His389Arg) and the c.1024G > A (p.Gly342Ser). The generated hiPSC line shows a normal karyotype, expresses pluripotency markers, and is able to differentiate into the three germ layers.
Generation of human induced pluripotent stem cell line (AOUMEYi001-A) from a patient affected by Congenital disorders of glycosylation (ALG8-CDG) using self-replicating RNA vector Rodolfo Tonin, Federica Feo, Silvia Falliano, Lorenzo Ferri, Laura Giunti, Martino Calamai, Elena Procopio, Francesco Mari, Valerio Conti, Ilaria Fanelli, Franco Bambi, Renzo Guerrini, Amelia Morrone Stem Cell Research, 2023 Congenital Disorders of Glycosylation (CDG) are rare inherited metabolic diseases caused by genetic defects in the glycosylation of proteins and lipids. In this study, we describe the generation and characterization of one human induced pluripotent stem cell (hiPSC) line from a 15-year-old male patient with CDG. The patient carried three variants, one (c.122G > A; p.Arg41Gln) inherited from his father and two (c.445 T > G; p.Leu149Arg and the novel c.980C > G; p.Thr327Arg) inherited from his mother in the ALG8 gene (OMIM #608103). The generated hiPSC line shows a normal karyotype, expresses pluripotency markers, and is able to differentiate into the three germ layers.
Stretch-activated ion channel TMEM63B associates with developmental and epileptic encephalopathies and progressive neurodegeneration Annalisa Vetro, Cristiana Pelorosso, Simona Balestrini, Alessio Masi, Sophie Hambleton, Emanuela Argilli, Valerio Conti, Simone Giubbolini, Rebekah Barrick, Gaber Bergant, Karin Writzl, Emilia K. Bijlsma, Theresa Brunet, Pilar Cacheiro, Davide Mei, Anita Devlin, Mariëtte J.V. Hoffer, Keren Machol, Guido Mannaioni, Masamune Sakamoto, Manoj P. Menezes, Thomas Courtin, Elliott Sherr, Riccardo Parra, Ruth Richardson, Tony Roscioli, Marcello Scala, Celina von Stülpnagel, Damian Smedley, Annalaura Torella, Jun Tohyama, Reiko Koichihara, Keisuke Hamada, Kazuhiro Ogata, Takashi Suzuki, Atsushi Sugie, Jasper J. van der Smagt, Koen van Gassen, Stephanie Valence, Emma Vittery, Stephen Malone, Mitsuhiro Kato, Naomichi Matsumoto, Gian Michele Ratto, Renzo Guerrini, Francesca Pochiero, Francesco Mari, Venkateswaran Ramesh, Valeria Capra, Margherita Mancardi, Boris Keren, Cyiril Mignot, Matteo Lulli, Kendall Parks, Helen Griffin, Melanie Brugger, Vincenzo Nigro, Yuko Hirata, Reiko Koichihara, Borut Peterlin, Yuko Hirata, Ryuto Maki, Yohei Nitta, John C. Ambrose, Prabhu Arumugam, Roel Bevers, Marta Bleda, Freya Boardman-Pretty, Christopher R. Boustred, Helen Brittain, Matthew A. Brown, Mark J. Caulfield, Georgia C. Chan, Adam Giess, John N. Griffin, Angela Hamblin, Shirley Henderson, Tim J.P. Hubbard, Rob Jackson, Louise J. Jones, Dalia Kasperaviciute, Melis Kayikci, Athanasios Kousathanas, Lea Lahnstein, Anna Lakey, Sarah E.A. Leigh, Ivonne U.S. Leong, Javier F. Lopez, Fiona Maleady-Crowe, Meriel McEntagart, Federico Minneci, Jonathan Mitchell, Loukas Moutsianas, Michael Mueller, Nirupa Murugaesu, Anna C. Need, Peter O’Donovan, Chris A. Odhams, Christine Patch, Daniel Perez-Gil, Marina B. Pereira, John Pullinger, Tahrima Rahim, Augusto Rendon, Tim Rogers, Kevin Savage, Kushmita Sawant, Richard H. Scott, Afshan Siddiq, Alexander Sieghart, Samuel C. Smith, Alona Sosinsky, Alexander Stuckey, Mélanie Tanguy, Ana Lisa Taylor Tavares, Ellen R.A. Thomas, Simon R. Thompson, Arianna Tucci, Matthew J. Welland, Eleanor Williams, Katarzyna Witkowska, Suzanne M. Wood, Magdalena Zarowiecki American Journal of Human Genetics, 2023 By converting physical forces into electrical signals or triggering intracellular cascades, stretch-activated ion channels allow the cell to respond to osmotic and mechanical stress. Knowledge of the pathophysiological mechanisms underlying associations of stretch-activated ion channels with human disease is limited. Here, we describe 17 unrelated individuals with severe early-onset developmental and epileptic encephalopathy (DEE), intellectual disability, and severe motor and cortical visual impairment associated with progressive neurodegenerative brain changes carrying ten distinct heterozygous variants of TMEM63B, encoding for a highly conserved stretch-activated ion channel. The variants occurred de novo in 16/17 individuals for whom parental DNA was available and either missense, including the recurrent p.Val44Met in 7/17 individuals, or in-frame, all affecting conserved residues located in transmembrane regions of the protein. In 12 individuals, hematological abnormalities co-occurred, such as macrocytosis and hemolysis, requiring blood transfusions in some. We modeled six variants (p.Val44Met, p.Arg433His, p.Thr481Asn, p.Gly580Ser, p.Arg660Thr, and p.Phe697Leu), each affecting a distinct transmembrane domain of the channel, in transfected Neuro2a cells and demonstrated inward leak cation currents across the mutated channel even in isotonic conditions, while the response to hypo-osmotic challenge was impaired, as were the Ca2+ transients generated under hypo-osmotic stimulation. Ectopic expression of the p.Val44Met and p.Gly580Cys variants in Drosophila resulted in early death. TMEM63B-associated DEE represents a recognizable clinicopathological entity in which altered cation conductivity results in a severe neurological phenotype with progressive brain damage and early-onset epilepsy associated with hematological abnormalities in most individuals.
Mechanism of KMT5B haploinsufficiency in neurodevelopment in humans and mice Sarah E. Sheppard, Laura Bryant, Rochelle N. Wickramasekara, Courtney Vaccaro, Brynn Robertson, Jodi Hallgren, Jason Hulen, Cynthia J. Watson, Victor Faundes, Yannis Duffourd, Pearl Lee, M. Celeste Simon, Xavier de la Cruz, Natália Padilla, Marco Flores-Mendez, Naiara Akizu, Jacqueline Smiler, Renata Pellegrino Da Silva, Dong Li, Michael March, Abdias Diaz-Rosado, Isabella Peixoto de Barcelos, Zhao Xiang Choa, Chin Yan Lim, Christèle Dubourg, Hubert Journel, Florence Demurger, Maureen Mulhern, Cigdem Akman, Natalie Lippa, Marisa Andrews, Dustin Baldridge, John Constantino, Arie van Haeringen, Irina Snoeck-Streef, Penny Chow, Anne Hing, John M. Graham, Margaret Au, Laurence Faivre, Wei Shen, Rong Mao, Janice Palumbos, David Viskochil, William Gahl, Cynthia Tifft, Ellen Macnamara, Natalie Hauser, Rebecca Miller, Jessica Maffeo, Alexandra Afenjar, Diane Doummar, Boris Keren, Pamela Arn, Sarah Macklin-Mantia, Ilse Meerschaut, Bert Callewaert, André Reis, Christiane Zweier, Carole Brewer, Anand Saggar, Marie F. Smeland, Ajith Kumar, Frances Elmslie, Charu Deshpande, Mathilde Nizon, Benjamin Cogne, Yvette van Ierland, Martina Wilke, Marjon van Slegtenhorst, Suzanne Koudijs, Jin Yun Chen, David Dredge, Danielle Pier, Saskia Wortmann, Erik-Jan Kamsteeg, Johannes Koch, Devon Haynes, Lynda Pollack, Hannah Titheradge, Kara Ranguin, Anne-Sophie Denommé-Pichon, Sacha Weber, Rubén Pérez de la Fuente, Jaime Sánchez del Pozo, Jose Miguel Lezana Rosales, Pascal Joset, Katharina Steindl, Anita Rauch, Davide Mei, Francesco Mari, Renzo Guerrini, James Lespinasse, Frédéric Tran Mau-Them, Christophe Philippe, Benjamin Dauriat, Laure Raymond, Sébastien Moutton, Anna M. Cueto-González, Tiong Yang Tan, Cyril Mignot, Sarah Grotto, Florence Renaldo, Theodore G. Drivas, Laura Hennessy, Anna Raper, Ilaria Parenti, Frank J. Kaiser, Alma Kuechler, Øyvind L. Busk, Lily Islam, Jacob A. Siedlik, Lindsay B. Henderson, Jane Juusola, Richard Person, Rhonda E. Schnur, Antonio Vitobello, Siddharth Banka, Elizabeth J. Bhoj, Holly A. F. Stessman Science Advances, 2023 Pathogenic variants in KMT5B , a lysine methyltransferase, are associated with global developmental delay, macrocephaly, autism, and congenital anomalies (OMIM # 617788). Given the relatively recent discovery of this disorder, it has not been fully characterized. Deep phenotyping of the largest ( n = 43) patient cohort to date identified that hypotonia and congenital heart defects are prominent features that were previously not associated with this syndrome. Both missense variants and putative loss-of-function variants resulted in slow growth in patient-derived cell lines. KMT5B homozygous knockout mice were smaller in size than their wild-type littermates but did not have significantly smaller brains, suggesting relative macrocephaly, also noted as a prominent clinical feature. RNA sequencing of patient lymphoblasts and Kmt5b haploinsufficient mouse brains identified differentially expressed pathways associated with nervous system development and function including axon guidance signaling. Overall, we identified additional pathogenic variants and clinical features in KMT5B -related neurodevelopmental disorder and provide insights into the molecular mechanisms of the disorder using multiple model systems.
A Schematic Approach to Defining the Prevalence of COL VI Variants in Five Years of Next-Generation Sequencing Gemma Marinella, Guja Astrea, Bianca Buchignani, Denise Cassandrini, Stefano Doccini, Massimiliano Filosto, Daniele Galatolo, Salvatore Gallone, Fabio Giannini, Diego Lopergolo, Maria Antonietta Maioli, Francesca Magri, Alessandro Malandrini, Paola Mandich, Francesco Mari, Roberto Massa, Sabrina Mata, Federico Melani, Maurizio Moggio, Tiziana E. Mongini, Rosa Pasquariello, Elena Pegoraro, Federica Ricci, Giulia Ricci, Carmelo Rodolico, Anna Rubegni, Gabriele Siciliano, Martina Sperti, Chiara Ticci, Paola Tonin, Filippo M. Santorelli, Roberta Battini International Journal of Molecular Sciences, 2022 Objective: To define the prevalence of variants in collagen VI genes through a next-generation sequencing (NGS) approach in undiagnosed patients with suspected neuromuscular disease and to propose a diagnostic flowchart to assess the real pathogenicity of those variants. Methods: In the past five years, we have collected clinical and molecular information on 512 patients with neuromuscular symptoms referred to our center. To pinpoint variants in COLVI genes and corroborate their real pathogenicity, we sketched a multistep flowchart, taking into consideration the bioinformatic weight of the gene variants, their correlation with clinical manifestations and possible effects on protein stability and expression. Results: In Step I, we identified variants in COLVI-related genes in 48 patients, of which three were homozygous variants (Group 1). Then, we sorted variants according to their CADD score, clinical data and complementary studies (such as muscle and skin biopsy, study of expression of COLVI on fibroblast or muscle and muscle magnetic resonance). We finally assessed how potentially pathogenic variants (two biallelic and 12 monoallelic) destabilize COL6A1-A2-A3 subunits. Overall, 15 out of 512 patients were prioritized according to this pipeline. In seven of them, we confirmed reduced or absent immunocytochemical expression of collagen VI in cultured skin fibroblasts or in muscle tissue. Conclusions: In a real-world diagnostic scenario applied to heterogeneous neuromuscular conditions, a multistep integration of clinical and molecular data allowed the identification of about 3% of those patients harboring pathogenetic collagen VI variants.
Molecular analysis of SMARD1 patient-derived cells demonstrates that nonsense-mediated mRNA decay is impaired Michela Taiana, Alessandra Govoni, Sabrina Salani, Nicole Kleinschmidt, Noemi Galli, Matteo Saladini, Stefano Bruno Ghezzi, Valentina Melzi, Margherita Bersani, Roberto Del Bo, Oliver Muehlemann, Enrico Bertini, Valeria Sansone, Emilio Albamonte, Sonia Messina, Francesco Mari, Elisabetta Cesaroni, Liliana Porfiri, Francesco Danilo Tiziano, Gian Luca Vita, Maria Sframeli, Carmen Bonanno, Nereo Bresolin, Giacomo Comi, Stefania Corti, Monica Nizzardo Journal of Neurology Neurosurgery and Psychiatry, 2022 peroxidase–conjugated antibody (Molecular Probes/Invitrogen) in saturating solution. The western
Bi-allelic variants in MTMR5/SBF1 cause Charcot-Marie-Tooth type 4B3 featuring mitochondrial dysfunction Beatrice Berti, Giovanna Longo, Francesco Mari, Stefano Doccini, Ilaria Piccolo, Maria Alice Donati, Francesca Moro, Renzo Guerrini, Filippo M. Santorelli, Vittoria Petruzzella BMC Medical Genomics, 2021 Background Charcot-Marie-Tooth disease (CMT) type 4B3 (CMT4B3) is a rare form of genetic neuropathy associated with variants in the MTMR5/SBF1 gene. MTMR5/SBF1 is a pseudophosphatase predicted to regulate endo-lysosomal trafficking in tandem with other MTMRs. Although almost ubiquitously expressed, pathogenic variants primarily impact on the peripheral nervous system, corroborating the involvement of MTMR5/SBF1 and its molecular partners in Schwann cells-mediated myelinization. Case presentation We report a case of severe CMT4B3 characterized by early-onset motor and axonal polyneuropathy in an Italian child in absence of any evidence of brain and spine MRI abnormalities or intellectual disability and with a biochemical profile suggestive of mitochondrial disease. Using an integrated approach combining both NGS gene panels and WES analysis, we identified two novel compound heterozygous missense variants in MTMR5/SBF1 gene, p.R763H (c.2291G > A) and p.G1064E (c.3194G > A). Studies in muscle identified partial defects of oxidative metabolism. Conclusion We describe the first case of an early onset severe polyneuropathy with motor and axonal involvement, due to recessive variants in the MTMR5/SBF1 gene, with no evidence of brain and spine MRI abnormalities, intellectual disability, no clinical and neurophysiological evidences of distal sensory impairment, and rapid neuromuscular deterioration. This report suggests that MTMR5/SBF1 should be considered in cases of infantile-onset CMT with secondary mitochondrial dysfunction.
Leopard-like retinopathy and severe early-onset portal hypertension expand the phenotype of KARS1-related syndrome: a case report Francesca Peluso, V. Palazzo, G. Indolfi, F. Mari, Roberta Pasqualetti, E. Procopio, C. Nesti, R. Guerrini, F. Santorelli, S. Giglio BMC Medical Genomics, 2021 Background Mutations in lysyl-tRNA synthetase ( KARS1 ), an enzyme that charges tRNA with the amino acid lysine in both the cytoplasm and mitochondria, have been associated thus far with autosomal recessive Charcot–Marie–Tooth type CMTRIB, hearing loss type DFNB89, and mitochondrial encephalohepatopathy (MEH) featuring neurodevelopmental disorders with microcephaly, white matter changes, and cardiac and hepatic failure in less than 30 patients. Case presentation We report the clinical, biochemical and molecular findings of a 14-month-old girl with severe MEH compatible clinical features, profound sensorineural hearing loss, leopard spot retinopathy, pancytopenia, and advanced liver disease with portal hypertension leading to death at the age of 30 months. Conclusions Whole exome sequencing identified two rare variants in KARS1 gene. Our report expands the allelic and clinical features of tRNA synthase disorders. Moreover, with our report we confirm the usefulness of WES as first tier diagnostic method in infants with complex multisystem phenotypes.
The diagnostic approach to mitochondrial disorders in children in the era of next-generation sequencing: A 4-year cohort study Deborah Tolomeo, Daniele Orsucci, Claudia Nesti, Jacopo Baldacci, Roberta Battini, Claudio Bruno, Giorgia Bruno, Denise Cassandrini, Stefano Doccini, M. Alice Donati, Annarita Ferrari, Simona Fiori, Chiara Fiorillo, Renzo Guerrini, Francesco Mari, Martino Montomoli, Francesca Pochiero, Elena Procopio, Lucia Ruggiero, Simone Sampaolo, Federico Sicca, Chiara Ticci, Anna Rubegni, Filippo M. Santorelli Journal of Clinical Medicine, 2021
ATP1A2-and ATP1A3-associated early profound epileptic encephalopathy and polymicrogyria Annalisa Vetro, Hang N Nielsen, Rikke Holm, Robert F Hevner, Elena Parrini, Zoe Powis, Rikke S Møller, Cristina Bellan, Alessandro Simonati, Gaétan Lesca, Katherine L Helbig, Elizabeth E Palmer, Davide Mei, Elisa Ballardini, Arie Van Haeringen, Steffen Syrbe, Vincenzo Leuzzi, Giovanni Cioni, Cynthia J Curry, Gregory Costain, Margherita Santucci, Karen Chong, Grazia M S Mancini, Jill Clayton-Smith, Stefania Bigoni, Ingrid E Scheffer, William B Dobyns, Bente Vilsen, Renzo Guerrini, Damien Sanlaville, Rani Sachdev, Ian Andrews, Francesco Mari, Anna Cavalli, Carmen Barba, Beatrice De Maria, Giampaolo Garani, Johannes R Lemke, Mario Mastrangelo, Emily Tam, Elizabeth Donner, Helen Branson, Fabiola P Monteiro, Fernando Kok, Katherine B Howell, Stephanie Leech, Heather Mefford, Alison Muir, and Brain, 2021
Next Generation Molecular Diagnosis of Hereditary Spastic Paraplegias: An Italian Cross-Sectional Study Angelica D'Amore, Alessandra Tessa, Carlo Casali, Maria Teresa Dotti, Alessandro Filla, Gabriella Silvestri, Antonella Antenora, Guja Astrea, Melissa Barghigiani, Roberta Battini, Carla Battisti, Irene Bruno, Cristina Cereda, Clemente Dato, Giuseppe Di Iorio, Vincenzo Donadio, Monica Felicori, Nicola Fini, Chiara Fiorillo, Salvatore Gallone, Federica Gemignani, Gian Luigi Gigli, Claudio Graziano, Renzo Guerrini, Fiorella Gurrieri, Ariana Kariminejad, Maria Lieto, Charles Marques LourenḈo, Alessandro Malandrini, Paola Mandich, Christian Marcotulli, Francesco Mari, Luca Massacesi, Maria A. B. Melone, Andrea Mignarri, Roberta Milone, Olimpia Musumeci, Elena Pegoraro, Alessia Perna, Antonio Petrucci, Antonella Pini, Francesca Pochiero, Maria Roser Pons, Ivana Ricca, Salvatore Rossi, Marco Seri, Franco Stanzial, Francesca Tinelli, Antonio Toscano, Mariarosaria Valente, Antonio Federico, Anna Rubegni, Filippo Maria Santorelli Frontiers in Neurology, 2018
Delineating SPTAN1 associated phenotypes: From isolated epilepsy to encephalopathy with progressive brain atrophy Steffen Syrbe, Frederike L Harms, Elena Parrini, Martino Montomoli, Ulrike Mütze, Katherine L Helbig, Tilman Polster, Beate Albrecht, Ulrich Bernbeck, Ellen van Binsbergen, Saskia Biskup, Lydie Burglen, Jonas Denecke, Bénédicte Heron, Henrike O Heyne, Georg F Hoffmann, Frauke Hornemann, Takeshi Matsushige, Ryuki Matsuura, Mitsuhiro Kato, G Christoph Korenke, Alma Kuechler, Constanze Lämmer, Andreas Merkenschlager, Cyril Mignot, Susanne Ruf, Mitsuko Nakashima, Hirotomo Saitsu, Hannah Stamberger, Tiziana Pisano, Jun Tohyama, Sarah Weckhuysen, Wendy Werckx, Julia Wickert, Francesco Mari, Nienke E Verbeek, Rikke S Møller, Bobby Koeleman, Naomichi Matsumoto, William B Dobyns, Domenica Battaglia, Johannes R Lemke, Kerstin Kutsche, Renzo Guerrini Brain, 2017
