@article {737, title = {ASC-1 Is a Cell Cycle Regulator Associated with Severe and Mild Forms of Myopathy.}, journal = {Ann Neurol}, volume = {87}, year = {2020}, month = {2020 02}, pages = {217-232}, abstract = {

OBJECTIVE: Recently, the ASC-1 complex has been identified as a mechanistic link between amyotrophic lateral sclerosis and spinal muscular atrophy (SMA), and 3 mutations of the ASC-1 gene TRIP4 have been associated with SMA or congenital myopathy. Our goal was to define ASC-1 neuromuscular function and the phenotypical spectrum associated with TRIP4 mutations.

METHODS: Clinical, molecular, histological, and magnetic resonance imaging studies were made in 5 families with 7 novel TRIP4 mutations. Fluorescence activated cell sorting and Western blot were performed in patient-derived fibroblasts and muscles and in Trip4 knocked-down C2C12 cells.

RESULTS: All mutations caused ASC-1 protein depletion. The clinical phenotype was purely myopathic, ranging from lethal neonatal to mild ambulatory adult patients. It included early onset axial and proximal weakness, scoliosis, rigid spine, dysmorphic facies, cutaneous involvement, respiratory failure, and in the older cases, dilated cardiomyopathy. Muscle biopsies showed multiminicores, nemaline rods, cytoplasmic bodies, caps, central nuclei, rimmed fibers, and/or mild endomysial fibrosis. ASC-1 depletion in C2C12 and in patient-derived fibroblasts and muscles caused accelerated proliferation, altered expression of cell cycle proteins, and/or shortening of the G0/G1 cell cycle phase leading to cell size reduction.

INTERPRETATION: Our results expand the phenotypical and molecular spectrum of TRIP4-associated disease to include mild adult forms with or without cardiomyopathy, associate ASC-1 depletion with isolated primary muscle involvement, and establish TRIP4 as a causative gene for several congenital muscle diseases, including nemaline, core, centronuclear, and cytoplasmic-body myopathies. They also identify ASC-1 as a novel cell cycle regulator with a key role in cell proliferation, and underline transcriptional coregulation defects as a novel pathophysiological mechanism. ANN NEUROL 2020;87:217-232.

}, keywords = {Adult, Amino Acid Transport System y+, Cell Cycle, Cells, Cultured, Child, Child, Preschool, Female, Fibroblasts, Humans, Infant, Male, Middle Aged, Muscle Proteins, Muscle, Skeletal, Muscular Diseases, Mutation, Pedigree, Phenotype, Transcription Factors}, issn = {1531-8249}, doi = {10.1002/ana.25660}, author = {Villar-Quiles, Roc{\'\i}o N and Catervi, Fabio and Cabet, Eva and Juntas-Morales, Raul and Genetti, Casie A and Gidaro, Teresa and Koparir, Asuman and Yuksel, Adnan and Coppens, Sandra and Deconinck, Nicolas and Pierce-Hoffman, Emma and Lornage, Xavi{\`e}re and Durigneux, Julien and Laporte, Jocelyn and Rendu, John and Romero, Norma B and Beggs, Alan H and Servais, Laurent and Coss{\'e}e, Mireille and Oliv{\'e}, Montse and B{\"o}hm, Johann and Duband-Goulet, Isabelle and Ferreiro, Ana} } @article {561, title = {Novel SPEG mutations in congenital myopathies: Genotype-phenotype correlations.}, journal = {Muscle Nerve}, volume = {59}, year = {2019}, month = {2019 03}, pages = {357-362}, abstract = {

INTRODUCTION: Centronuclear myopathies (CNMs) are a subtype of congenital myopathies (CMs) characterized by muscle weakness, predominant type 1 fibers, and increased central nuclei. SPEG (striated preferentially expressed protein kinase) mutations have recently been identified in 7 CM patients (6 with CNMs). We report 2 additional patients with SPEG mutations expanding the phenotype and evaluate genotype-phenotype correlations associated with SPEG mutations.

METHODS: Using whole exome/genome sequencing in CM families, we identified novel recessive SPEG mutations in 2 patients.

RESULTS: Patient 1, with severe muscle weakness requiring respiratory support, dilated cardiomyopathy, ophthalmoplegia, and findings of nonspecific CM on muscle biopsy carried a homozygous SPEG mutation (p.Val3062del). Patient 2, with milder muscle weakness, ophthalmoplegia, and CNM carried compound heterozygous mutations (p.Leu728Argfs*82) and (p.Val2997Glyfs*52).

CONCLUSIONS: The 2 patients add insight into genotype-phenotype correlations of SPEG-associated CMs. Clinicians should consider evaluating a CM patient for SPEG mutations even in the absence of CNM features. Muscle Nerve 59:357-362, 2019.

}, keywords = {Biopsy, Child, Child, Preschool, Consanguinity, Exome, Female, Genetic Association Studies, Humans, Infant, Male, Muscle Proteins, Muscle Weakness, Muscle, Skeletal, Mutation, Myopathies, Structural, Congenital, Protein-Serine-Threonine Kinases, Sequence Analysis}, issn = {1097-4598}, doi = {10.1002/mus.26378}, author = {Qualls, Anita E and Donkervoort, Sandra and Herkert, Johanna C and D{\textquoteright}Gama, Alissa M and Bharucha-Goebel, Diana and Collins, James and Chao, Katherine R and Foley, A Reghan and Schoots, Mirthe H and Jongbloed, Jan D H and B{\"o}nnemann, Carsten G and Agrawal, Pankaj B} } @article {487, title = {Detection of variants in dystroglycanopathy-associated genes through the application of targeted whole-exome sequencing analysis to a large cohort of patients with unexplained limb-girdle muscle weakness.}, journal = {Skelet Muscle}, volume = {8}, year = {2018}, month = {2018 07 30}, pages = {23}, abstract = {

BACKGROUND: Dystroglycanopathies are a clinically and genetically heterogeneous group of disorders that are typically characterised by limb-girdle muscle weakness. Mutations in 18 different genes have been associated with dystroglycanopathies, the encoded proteins of which typically modulate the binding of α-dystroglycan to extracellular matrix ligands by altering its glycosylation. This results in a disruption of the structural integrity of the myocyte, ultimately leading to muscle degeneration.

METHODS: Deep phenotypic information was gathered using the PhenoTips online software for 1001 patients with unexplained limb-girdle muscle weakness from 43 different centres across 21 European and Middle Eastern countries. Whole-exome sequencing with at least 250~ng DNA was completed using an Illumina exome capture and a 38~Mb baited target. Genes known to be associated with dystroglycanopathies were analysed for disease-causing variants.

RESULTS: Suspected pathogenic variants were detected in DPM3, ISPD, POMT1 and FKTN in one patient each, in POMK in two patients, in GMPPB in three patients, in FKRP in eight patients and in POMT2 in ten patients. This indicated a frequency of 2.7\% for the disease group within the cohort of 1001 patients with unexplained limb-girdle muscle weakness. The phenotypes of the 27 patients were highly variable, yet with a fundamental presentation of proximal muscle weakness and elevated serum creatine kinase.

CONCLUSIONS: Overall, we have identified 27 patients with suspected pathogenic variants in dystroglycanopathy-associated genes. We present evidence for the genetic and phenotypic diversity of the dystroglycanopathies as a disease group, while also highlighting the advantage of incorporating next-generation sequencing into the diagnostic pathway of rare diseases.

}, keywords = {Adolescent, Adult, Aged, Aged, 80 and over, Child, Child, Preschool, Dystroglycans, Female, Genetic Predisposition to Disease, Genetic Variation, Glycosylation, Heterozygote, Homozygote, Humans, Male, Middle Aged, Muscle Proteins, Muscular Dystrophies, Limb-Girdle, Mutation, Phenotype, Whole Exome Sequencing, Young Adult}, issn = {2044-5040}, doi = {10.1186/s13395-018-0170-1}, author = {Johnson, Katherine and Bertoli, Marta and Phillips, Lauren and Topf, Ana and Van den Bergh, Peter and Vissing, John and Witting, Nanna and Nafissi, Shahriar and Jamal-Omidi, Shirin and {\L}usakowska, Anna and Kostera-Pruszczyk, Anna and Potulska-Chromik, Anna and Deconinck, Nicolas and Wallgren-Pettersson, Carina and Strang-Karlsson, Sonja and Colomer, Jaume and Claeys, Kristl G and De Ridder, Willem and Baets, Jonathan and von der Hagen, Maja and Fern{\'a}ndez-Torr{\'o}n, Roberto and Zulaica Ijurco, Miren and Espinal Valencia, Juan Bautista and Hahn, Andreas and Durmus, Hacer and Willis, Tracey and Xu, Liwen and Valkanas, Elise and Mullen, Thomas E and Lek, Monkol and MacArthur, Daniel G and Straub, Volker} } @article {638, title = {A defect in myoblast fusion underlies Carey-Fineman-Ziter syndrome.}, journal = {Nat Commun}, volume = {8}, year = {2017}, month = {2017 07 06}, pages = {16077}, abstract = {

Multinucleate cellular syncytial formation is a hallmark of skeletal muscle differentiation. Myomaker, encoded by Mymk (Tmem8c), is a well-conserved plasma membrane protein required for myoblast fusion to form multinucleated myotubes in mouse, chick, and zebrafish. Here, we report that autosomal recessive mutations in MYMK (OMIM 615345) cause Carey-Fineman-Ziter syndrome in humans (CFZS; OMIM 254940) by reducing but not eliminating MYMK function. We characterize MYMK-CFZS as a congenital myopathy with marked facial weakness and additional clinical and pathologic features that distinguish it from other congenital neuromuscular syndromes. We show that a heterologous cell fusion assay in vitro and allelic complementation experiments in mymk knockdown and mymk zebrafish in vivo can differentiate between MYMK wild type, hypomorphic and null alleles. Collectively, these data establish that MYMK activity is necessary for normal muscle development and maintenance in humans, and expand the spectrum of congenital myopathies to include cell-cell fusion deficits.

}, keywords = {Adult, Amino Acid Sequence, Animals, Cell Fusion, Child, Disease Models, Animal, Embryo, Nonmammalian, Female, Gene Expression, Genes, Recessive, Genetic Complementation Test, Humans, Infant, Male, Membrane Proteins, Mobius Syndrome, Morphogenesis, Muscle Proteins, Muscle, Skeletal, Muscular Diseases, Mutation, Myoblasts, Pedigree, Pierre Robin Syndrome, Sequence Alignment, Sequence Homology, Amino Acid, Zebrafish, Zebrafish Proteins}, issn = {2041-1723}, doi = {10.1038/ncomms16077}, author = {Di Gioia, Silvio Alessandro and Connors, Samantha and Matsunami, Norisada and Cannavino, Jessica and Rose, Matthew F and Gilette, Nicole M and Artoni, Pietro and de Macena Sobreira, Nara Lygia and Chan, Wai-Man and Webb, Bryn D and Robson, Caroline D and Cheng, Long and Van Ryzin, Carol and Ramirez-Martinez, Andres and Mohassel, Payam and Leppert, Mark and Scholand, Mary Beth and Grunseich, Christopher and Ferreira, Carlos R and Hartman, Tyler and Hayes, Ian M and Morgan, Tim and Markie, David M and Fagiolini, Michela and Swift, Amy and Chines, Peter S and Speck-Martins, Carlos E and Collins, Francis S and Jabs, Ethylin Wang and B{\"o}nnemann, Carsten G and Olson, Eric N and Carey, John C and Robertson, Stephen P and Manoli, Irini and Engle, Elizabeth C} } @article {384, title = {Neonatal fractures as a presenting feature of LMOD3-associated congenital myopathy.}, journal = {Am J Med Genet A}, volume = {173}, year = {2017}, month = {2017 Oct}, pages = {2789-2794}, abstract = {

Nemaline myopathy is a rare inherited disorder characterized by weakness, hypotonia, and depressed deep tendon reflexes. It is clinically and genetically heterogeneous, with the most severe phenotype presenting as perinatal akinesia, severe muscle weakness, feeding difficulties and respiratory failure, leading to early mortality. Pathogenic variants in 12 genes, encoding components of the sarcomere or factors related to myogenesis, have been reported in patients affected with the disorder. Here, we describe an early, lethal presentation of decreased fetal movements, hypotonia, muscle weakness, and neonatal respiratory failure requiring ventilator support in three siblings from a consanguineous family. All exhibited perinatal fractures, and thus, a skeletal dysplasia was considered as possibly contributing to the phenotype. However, whole exome sequencing revealed a homozygous, loss-of-function pathogenic variant in LMOD3, which has recently been associated with nemaline myopathy and, in a subset of patients, perinatal fractures. This case demonstrates the importance of considering congenital neuromuscular disorders in the differential diagnosis of perinatal fractures.

}, keywords = {Female, Fractures, Bone, Homozygote, Humans, Infant, Newborn, Male, Muscle Proteins, Mutation, Myopathies, Structural, Congenital, Pedigree}, issn = {1552-4833}, doi = {10.1002/ajmg.a.38383}, author = {Abbott, Megan and Jain, Mahim and Pferdehirt, Rachel and Chen, Yuqing and Tran, Alyssa and Duz, Mehmet B and Seven, Mehmet and Gibbs, Richard A and Muzny, Donna and Lee, Brendan and Marom, Ronit and Burrage, Lindsay C} } @article {387, title = {Novel Genetic Triggers and Genotype-Phenotype Correlations in Patients With Left Ventricular Noncompaction.}, journal = {Circ Cardiovasc Genet}, volume = {10}, year = {2017}, month = {2017 Aug}, abstract = {

BACKGROUND: Left ventricular noncompaction (LVNC) is a genetically and phenotypically heterogeneous disease and, although increasingly recognized in clinical practice, there is a lack of widely accepted diagnostic criteria. We sought to identify novel genetic causes of LVNC and describe genotype-phenotype correlations.

METHODS AND RESULTS: A total of 190 patients from 174 families with left ventricular hypertrabeculation (LVHT) or LVNC were referred for cardiac magnetic resonance and whole-exome sequencing. A total of 425 control individuals were included to identify variants of interest (VOIs). We found an excess of 138 VOIs in 102 (59\%) unrelated patients in 54 previously identified LVNC or other known cardiomyopathy genes. VOIs were found in 68 of 90 probands with LVNC and 34 of 84 probands with LVHT (76\% and 40\%, respectively; <0.001). We identified 0, 1, and >=2 VOIs in 72, 74, and 28 probands, respectively. We found increasing number of VOIs in a patient strongly correlated with several markers of disease severity, including ratio of noncompacted to compacted myocardium (<0.001) and left ventricular ejection fraction (=0.01). The presence of sarcomeric gene mutations was associated with increased occurrence of late gadolinium enhancement (=0.004).

CONCLUSIONS: LVHT and LVNC likely represent a continuum of genotypic disease with differences in severity and variable phenotype explained, in part, by the number of VOIs and whether mutations are present in sarcomeric or nonsarcomeric genes. Presence of VOIs is common in patients with LVHT. Our findings expand the current clinical and genetic diagnostic approaches for patients with LVHT and LVNC.

}, keywords = {Adaptor Proteins, Signal Transducing, Adolescent, Adult, Aged, Cardiac Myosins, Carrier Proteins, Child, Connectin, Female, Genetic Association Studies, Genetic Variation, Heart Ventricles, Humans, LIM Domain Proteins, Magnetic Resonance Imaging, Cine, Male, Middle Aged, Muscle Proteins, Myocardium, Myosin Heavy Chains, Prospective Studies, Severity of Illness Index, Tropomyosin, Ventricular Dysfunction, Left, Young Adult}, issn = {1942-3268}, doi = {10.1161/CIRCGENETICS.117.001763}, author = {Miszalski-Jamka, Karol and Jefferies, John L and Mazur, Wojciech and G{\l}owacki, Jan and Hu, Jianhong and Lazar, Monika and Gibbs, Richard A and Liczko, Jacek and K{\l}y{\'s}, Jan and Venner, Eric and Muzny, Donna M and Rycaj, Jaros{\l}aw and Bia{\l}kowski, Jacek and Kluczewska, Ewa and Kalarus, Zbigniew and Jhangiani, Shalini and Al-Khalidi, Hussein and Kukulski, Tomasz and Lupski, James R and Craigen, William J and Bainbridge, Matthew N} } @article {35, title = {IFT52 mutations destabilize anterograde complex assembly, disrupt ciliogenesis and result in short rib polydactyly syndrome.}, journal = {Hum Mol Genet}, volume = {25}, year = {2016}, month = {2016 Sep 15}, pages = {4012-4020}, abstract = {

The short-rib polydactyly syndromes (SRPS) encompass a radiographically and genetically heterogeneous group of skeletal ciliopathies that are characterized by a long narrow chest, short extremities, and variable occurrence of polydactyly. Radiographic abnormalities include undermineralization of the calvarium, shortened and bowed appendicular bones, trident shaped acetabula and polydactyly. In a case of SRPS we identified compound heterozygosity for mutations in IFT52, which encodes a component of the anterograde intraflagellar transport complex. The IFT52 mutant cells synthesized a significantly reduced amount of IFT52 protein, leading to reduced synthesis of IFT74, IFT81, IFT88 and ARL13B, other key anterograde complex members. Ciliogenesis was also disrupted in the mutant cells, with a 60\% reduction in the presence of cilia on mutant cells and loss of cilia length regulation for the cells with cilia. These data demonstrate that IFT52 is essential for anterograde complex integrity and for the biosynthesis and maintenance of cilia. The data identify a new locus for SRPS and show that IFT52 mutations result in a ciliopathy with primary effects on the skeleton.

}, keywords = {Carrier Proteins, Cilia, Ciliopathies, Cytoskeletal Proteins, Flagella, Humans, Intracellular Signaling Peptides and Proteins, Multiprotein Complexes, Muscle Proteins, Mutation, Short Rib-Polydactyly Syndrome, Skeleton, Tumor Suppressor Proteins}, issn = {1460-2083}, doi = {10.1093/hmg/ddw241}, author = {Zhang, Wenjuan and Taylor, S Paige and Nevarez, Lisette and Lachman, Ralph S and Nickerson, Deborah A and Bamshad, Michael and Krakow, Deborah and Cohn, Daniel H} } @article {56, title = {Mutations in the Histone Modifier PRDM6 Are Associated with Isolated Nonsyndromic Patent Ductus Arteriosus.}, journal = {Am J Hum Genet}, volume = {98}, year = {2016}, month = {2016 06 02}, pages = {1082-1091}, abstract = {

Nonsyndromic patent ductus arteriosus (PDA) is a common congenital heart defect (CHD) with both inherited and acquired causes, but the disease mechanisms have remained elusive. Using combined genome-wide linkage analysis and whole-exome sequencing (WES), we identified independent mutations in PRDM6, which encodes a nuclear protein that is specific to vascular smooth muscle cells (VSMC), has histone methyl transferase activities, and acts as a transcriptional suppressor of contractile proteins. In~vitro assays showed that the mutations cause loss of function either by intracellular redistribution of the protein and/or by alteration of its methyltransferase activities. Wild-type embryonic ductus arteriosus (DA) exhibited high levels of PRDM6, which rapidly declined postnatally as the number of VSMCs necessary for ductus contraction increased. This dynamic change suggests that PRDM6 plays a key role in maintaining VSMCs in an undifferentiated stage in order to promote their proliferation and that its loss of activity results in premature differentiation and impaired remodeling of the DA. Our findings identify PRDM6 mutations as underlying genetic causes of nonsyndromic isolated PDA in humans and implicates the wild-type protein in epigenetic regulation of ductus remodeling.

}, keywords = {Cell Differentiation, Cells, Cultured, Ductus Arteriosus, Patent, Epigenesis, Genetic, Female, Fluorescent Antibody Technique, Histones, Humans, Immunoblotting, Male, Muscle Proteins, Muscle, Smooth, Vascular, Mutation, Pedigree, Transcription Factors}, issn = {1537-6605}, doi = {10.1016/j.ajhg.2016.03.022}, author = {Li, Na and Subrahmanyan, Lakshman and Smith, Emily and Yu, Xiaoqing and Zaidi, Samir and Choi, Murim and Mane, Shrikant and Nelson-Williams, Carol and Behjati, Mohaddeseh and Kazemi, Mohammad and Hashemi, Mohammad and Fathzadeh, Mohsen and Narayanan, Anand and Tian, Likun and Montazeri, Farhad and Mani, Mitra and Begleiter, Michael L and Coon, Brian G and Lynch, Henry T and Olson, Eric N and Zhao, Hongyu and Ruland, J{\"u}rgen and Lifton, Richard P and Mani, Arya} }