Journal of Personalized Medicine

Editorial

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Open AccessEditorial

Understanding Neuromuscular Health and Disease: Advances in Genetics, Omics, and Molecular Function

by William J. Duddy and Stephanie Duguez

J. Pers. Med. 2021, 11(5), 438; https://doi.org/10.3390/jpm11050438 - 20 May 2021

Viewed by 2660

Abstract

The field of neuromuscular research has seen considerable recent advances in the molecular and cellular understanding of muscle biology, and the treatment of neuromuscular disease [...] Full article

(This article belongs to the Special Issue Understanding Neuromuscular Health and Disease: Advances in Genetics, Omics, and Molecular Function)

Research

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14 pages, 3965 KiB

Open AccessArticle

A Genotype-Phenotype Correlation Study of Exon Skip-Equivalent In-Frame Deletions and Exon Skip-Amenable Out-of-Frame Deletions across the DMD Gene to Simulate the Effects of Exon-Skipping Therapies: A Meta-Analysis

by Saeed Anwar, Merry He, Kenji Rowel Q. Lim, Rika Maruyama and Toshifumi Yokota

J. Pers. Med. 2021, 11(1), 46; https://doi.org/10.3390/jpm11010046 - 14 Jan 2021

Cited by 10 | Viewed by 4612

Abstract

Dystrophinopathies are caused by mutations in the DMD gene. Out-of-frame deletions represent most mutational events in severe Duchenne muscular dystrophy (DMD), while in-frame deletions typically lead to milder Becker muscular dystrophy (BMD). Antisense oligonucleotide-mediated exon skipping converts an out-of-frame transcript to an in-frame [...] Read more.

Dystrophinopathies are caused by mutations in the DMD gene. Out-of-frame deletions represent most mutational events in severe Duchenne muscular dystrophy (DMD), while in-frame deletions typically lead to milder Becker muscular dystrophy (BMD). Antisense oligonucleotide-mediated exon skipping converts an out-of-frame transcript to an in-frame one, inducing a truncated but partially functional dystrophin protein. The reading frame rule, however, has many exceptions. We thus sought to simulate clinical outcomes of exon-skipping therapies for DMD exons from clinical data of exon skip-equivalent in-frame deletions, in which the expressed quasi-dystrophins are comparable to those resulting from exon-skipping therapies. We identified a total of 1298 unique patients with exon skip-equivalent mutations in patient registries and the existing literature. We classified them into skip-equivalent deletions of each exon and statistically compared the ratio of DMD/BMD and asymptomatic individuals across the DMD gene. Our analysis identified that five exons are associated with significantly milder phenotypes than all other exons when corresponding exon skip-equivalent in-frame deletion mutations occur. Most exon skip-equivalent in-frame deletions were associated with a significantly milder phenotype compared to corresponding exon skip-amenable out-of-frame mutations. This study indicates the importance of genotype-phenotype correlation studies in the rational design of exon-skipping therapies. Full article

(This article belongs to the Special Issue Understanding Neuromuscular Health and Disease: Advances in Genetics, Omics, and Molecular Function)

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10 pages, 2638 KiB

Open AccessArticle

Gene Editing Targeting the DUX4 Polyadenylation Signal: A Therapy for FSHD?

by Romains Joubert, Virginie Mariot, Marine Charpentier, Jean Paul Concordet and Julie Dumonceaux

J. Pers. Med. 2021, 11(1), 7; https://doi.org/10.3390/jpm11010007 - 23 Dec 2020

Cited by 13 | Viewed by 3535

Abstract

Facioscapulohumeral dystrophy (FSHD, OMIM: 158900, 158901) is the most common dystrophy in adults and so far, there is no treatment. Different loci of the disease have been characterized and they all lead to the aberrant expression of the DUX4 protein, which impairs the [...] Read more.

Facioscapulohumeral dystrophy (FSHD, OMIM: 158900, 158901) is the most common dystrophy in adults and so far, there is no treatment. Different loci of the disease have been characterized and they all lead to the aberrant expression of the DUX4 protein, which impairs the function of the muscle, ultimately leading to cell death. Here, we used gene editing to try to permanently shut down DUX4 expression by targeting its poly(A) sequence. We used transcription activator-like effector nucleases (TALEN) and CRISPR-Cas9 nucleases in vitro on FSHD myoblasts. More than 150 TOPO clones were sequenced and only indels were observed in 4%. Importantly, in 2 of them, the DUX4 poly(A) signal was eliminated at the genomic level but DUX4 mRNA was still produced thanks to the use of a non-canonical upstream poly(A) signal sequence. These experiments show that targeting DUX4 PAS at the genomic level might not be an appropriate gene editing strategy for FSHD therapy. Full article

(This article belongs to the Special Issue Understanding Neuromuscular Health and Disease: Advances in Genetics, Omics, and Molecular Function)

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18 pages, 3023 KiB

Open AccessArticle

Genotype–Phenotype Correlations in Duchenne and Becker Muscular Dystrophy Patients from the Canadian Neuromuscular Disease Registry

by Kenji Rowel Q. Lim, Quynh Nguyen and Toshifumi Yokota

J. Pers. Med. 2020, 10(4), 241; https://doi.org/10.3390/jpm10040241 - 23 Nov 2020

Cited by 24 | Viewed by 5174

Abstract

Duchenne muscular dystrophy (DMD) is a fatal neuromuscular disorder generally caused by out-of-frame mutations in the DMD gene. In contrast, in-frame mutations usually give rise to the milder Becker muscular dystrophy (BMD). However, this reading frame rule does not always hold true. Therefore, [...] Read more.

Duchenne muscular dystrophy (DMD) is a fatal neuromuscular disorder generally caused by out-of-frame mutations in the DMD gene. In contrast, in-frame mutations usually give rise to the milder Becker muscular dystrophy (BMD). However, this reading frame rule does not always hold true. Therefore, an understanding of the relationships between genotype and phenotype is important for informing diagnosis and disease management, as well as the development of genetic therapies. Here, we evaluated genotype–phenotype correlations in DMD and BMD patients enrolled in the Canadian Neuromuscular Disease Registry from 2012 to 2019. Data from 342 DMD and 60 BMD patients with genetic test results were analyzed. The majority of patients had deletions (71%), followed by small mutations (17%) and duplications (10%); 2% had negative results. Two deletion hotspots were identified, exons 3–20 and exons 45–55, harboring 86% of deletions. Exceptions to the reading frame rule were found in 13% of patients with deletions. Surprisingly, C-terminal domain mutations were associated with decreased wheelchair use and increased forced vital capacity. Dp116 and Dp71 mutations were also linked with decreased wheelchair use, while Dp140 mutations significantly predicted cardiomyopathy. Finally, we found that 12.3% and 7% of DMD patients in the registry could be treated with FDA-approved exon 51- and 53-skipping therapies, respectively. Full article

(This article belongs to the Special Issue Understanding Neuromuscular Health and Disease: Advances in Genetics, Omics, and Molecular Function)

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22 pages, 2665 KiB

Open AccessArticle

Multi-Omics Identifies Circulating miRNA and Protein Biomarkers for Facioscapulohumeral Dystrophy

by Christopher R. Heier, Aiping Zhang, Nhu Y Nguyen, Christopher B. Tully, Aswini Panigrahi, Heather Gordish-Dressman, Sachchida Nand Pandey, Michela Guglieri, Monique M. Ryan, Paula R. Clemens, Mathula Thangarajh, Richard Webster, Edward C. Smith, Anne M. Connolly, Craig M. McDonald, Peter Karachunski, Mar Tulinius, Amy Harper, Jean K. Mah, Alyson A. Fiorillo, Yi-Wen Chen and Cooperative International Neuromuscular Research Group (CINRG) Investigators Show full author list Hide full author list

J. Pers. Med. 2020, 10(4), 236; https://doi.org/10.3390/jpm10040236 - 19 Nov 2020

Cited by 12 | Viewed by 4543

Abstract

The development of therapeutics for muscle diseases such as facioscapulohumeral dystrophy (FSHD) is impeded by a lack of objective, minimally invasive biomarkers. Here we identify circulating miRNAs and proteins that are dysregulated in early-onset FSHD patients to develop blood-based molecular biomarkers. Plasma samples [...] Read more.

The development of therapeutics for muscle diseases such as facioscapulohumeral dystrophy (FSHD) is impeded by a lack of objective, minimally invasive biomarkers. Here we identify circulating miRNAs and proteins that are dysregulated in early-onset FSHD patients to develop blood-based molecular biomarkers. Plasma samples from clinically characterized individuals with early-onset FSHD provide a discovery group and are compared to healthy control volunteers. Low-density quantitative polymerase chain reaction (PCR)-based arrays identify 19 candidate miRNAs, while mass spectrometry proteomic analysis identifies 13 candidate proteins. Bioinformatic analysis of chromatin immunoprecipitation (ChIP)-seq data shows that the FSHD-dysregulated DUX4 transcription factor binds to regulatory regions of several candidate miRNAs. This panel of miRNAs also shows ChIP signatures consistent with regulation by additional transcription factors which are up-regulated in FSHD (FOS, EGR1, MYC, and YY1). Validation studies in a separate group of patients with FSHD show consistent up-regulation of miR-100, miR-103, miR-146b, miR-29b, miR-34a, miR-454, miR-505, and miR-576. An increase in the expression of S100A8 protein, an inflammatory regulatory factor and subunit of calprotectin, is validated by Enzyme-Linked Immunosorbent Assay (ELISA). Bioinformatic analyses of proteomics and miRNA data further support a model of calprotectin and toll-like receptor 4 (TLR4) pathway dysregulation in FSHD. Moving forward, this panel of miRNAs, along with S100A8 and calprotectin, merit further investigation as monitoring and pharmacodynamic biomarkers for FSHD. Full article

(This article belongs to the Special Issue Understanding Neuromuscular Health and Disease: Advances in Genetics, Omics, and Molecular Function)

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15 pages, 2695 KiB

Open AccessArticle

Comparison of Serum Pharmacodynamic Biomarkers in Prednisone-Versus Deflazacort-Treated Duchenne Muscular Dystrophy Boys

by Shefa Tawalbeh, Alison Samsel, Heather Gordish-Dressman, Yetrib Hathout, CINRG-DNHS Investigators and Utkarsh J. Dang

J. Pers. Med. 2020, 10(4), 164; https://doi.org/10.3390/jpm10040164 - 12 Oct 2020

Cited by 6 | Viewed by 3787

Abstract

Prednisone (Pred) and Deflazacort (Dfz) are commonly used glucocorticoids (GCs) for Duchenne muscular dystrophy (DMD) treatment and management. While GCs are known to delay the loss of ambulation and motor abilities, chronic use can result in onerous side effects, e.g., weight gain, growth [...] Read more.

Prednisone (Pred) and Deflazacort (Dfz) are commonly used glucocorticoids (GCs) for Duchenne muscular dystrophy (DMD) treatment and management. While GCs are known to delay the loss of ambulation and motor abilities, chronic use can result in onerous side effects, e.g., weight gain, growth stunting, loss of bone density, etc. Here, we use the CINRG Duchenne natural history study to gain insight into comparative safety of Pred versus Dfz treatment through GC-responsive pharmacodynamic (PD) biomarkers. Longitudinal trajectories of SOMAscan^® protein data obtained on serum of DMD boys aged 4 to 10 (Pred: n = 7; Dfz: n = 8) were analyzed after accounting for age and time on treatment. Out of the pre-specified biomarkers, seventeen candidate proteins were differentially altered between the two drugs (p < 0.05). These include IGFBP-2 and AGER associated with diabetes complications, and MMP-3 associated with extracellular remodeling. As a follow-up, IGFBP-2, MMP-3, and IGF-I were quantified with an ELISA using a larger sample size of DMD biosamples (Dfz: n = 17, Pred: n = 12; up to 76 sera samples) over a longer treatment duration. MMP-3 and IGFBP-2 validated the SOMAscan^® signal, however, IGF-I did not. This study identified GC-responsive biomarkers, some associated with safety, that highlight differential PD response between Dfz and Pred. Full article

(This article belongs to the Special Issue Understanding Neuromuscular Health and Disease: Advances in Genetics, Omics, and Molecular Function)

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14 pages, 1236 KiB

Open AccessArticle

Clinical and Laboratory Associations with Methotrexate Metabolism Gene Polymorphisms in Rheumatoid Arthritis

by Leon G. D’Cruz, Kevin G. McEleney, Kyle B. C. Tan, Priyank Shukla, Philip V. Gardiner, Patricia Connolly, Caroline Conway, Diego Cobice and David S. Gibson

J. Pers. Med. 2020, 10(4), 149; https://doi.org/10.3390/jpm10040149 - 26 Sep 2020

Cited by 12 | Viewed by 4438

Abstract

Rheumatoid arthritis (RA) is a chronic systemic autoimmune disease that causes loss of joint function and significantly reduces quality of life. Plasma metabolite concentrations of disease-modifying anti-rheumatic drugs (DMARDs) can influence treatment efficacy and toxicity. This study explored the relationship between DMARD-metabolising gene [...] Read more.

Rheumatoid arthritis (RA) is a chronic systemic autoimmune disease that causes loss of joint function and significantly reduces quality of life. Plasma metabolite concentrations of disease-modifying anti-rheumatic drugs (DMARDs) can influence treatment efficacy and toxicity. This study explored the relationship between DMARD-metabolising gene variants and plasma metabolite levels in RA patients. DMARD metabolite concentrations were determined by tandem mass-spectrometry in plasma samples from 100 RA patients with actively flaring disease collected at two intervals. Taqman probes were used to discriminate single-nucleotide polymorphism (SNP) genotypes in cohort genomic DNA: rs246240 (ABCC1), rs1476413 (MTHFR), rs2231142 (ABCG2), rs3740065 (ABCC2), rs4149081 (SLCO1B1), rs4846051 (MTHFR), rs10280623 (ABCB1), rs16853826 (ATIC), rs17421511 (MTHFR) and rs717620 (ABCC2). Mean plasma concentrations of methotrexate (MTX) and MTX-7-OH metabolites were higher (p < 0.05) at baseline in rs4149081 GA genotype patients. Patients with rs1476413 SNP TT or CT alleles have significantly higher (p < 0.001) plasma poly-glutamate metabolites at both study time points and correspondingly elevated disease activity scores. Patients with the rs17421511 SNP AA allele reported significantly lower pain scores (p < 0.05) at both study intervals. Genotyping strategies could help prioritise treatments to RA patients most likely to gain clinical benefit whilst minimizing toxicity. Full article

(This article belongs to the Special Issue Understanding Neuromuscular Health and Disease: Advances in Genetics, Omics, and Molecular Function)

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Review

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44 pages, 1169 KiB

Open AccessFeature PaperReview

Of rAAV and Men: From Genetic Neuromuscular Disorder Efficacy and Toxicity Preclinical Studies to Clinical Trials and Back

by Laurine Buscara, David-Alexandre Gross and Nathalie Daniele

J. Pers. Med. 2020, 10(4), 258; https://doi.org/10.3390/jpm10040258 - 28 Nov 2020

Cited by 18 | Viewed by 6174

Abstract

Neuromuscular disorders are a large group of rare pathologies characterised by skeletal muscle atrophy and weakness, with the common involvement of respiratory and/or cardiac muscles. These diseases lead to life-long motor deficiencies and specific organ failures, and are, in their worst-case scenarios, life [...] Read more.

Neuromuscular disorders are a large group of rare pathologies characterised by skeletal muscle atrophy and weakness, with the common involvement of respiratory and/or cardiac muscles. These diseases lead to life-long motor deficiencies and specific organ failures, and are, in their worst-case scenarios, life threatening. Amongst other causes, they can be genetically inherited through mutations in more than 500 different genes. In the last 20 years, specific pharmacological treatments have been approved for human usage. However, these “à-la-carte” therapies cover only a very small portion of the clinical needs and are often partially efficient in alleviating the symptoms of the disease, even less so in curing it. Recombinant adeno-associated virus vector-mediated gene transfer is a more general strategy that could be adapted for a large majority of these diseases and has proved very efficient in rescuing the symptoms in many neuropathological animal models. On this solid ground, several clinical trials are currently being conducted with the whole-body delivery of the therapeutic vectors. This review recapitulates the state-of-the-art tools for neuron and muscle-targeted gene therapy, and summarises the main findings of the spinal muscular atrophy (SMA), Duchenne muscular dystrophy (DMD) and X-linked myotubular myopathy (XLMTM) trials. Despite promising efficacy results, serious adverse events of various severities were observed in these trials. Possible leads for second-generation products are also discussed. Full article

(This article belongs to the Special Issue Understanding Neuromuscular Health and Disease: Advances in Genetics, Omics, and Molecular Function)

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28 pages, 732 KiB

Open AccessReview

What Can Machine Learning Approaches in Genomics Tell Us about the Molecular Basis of Amyotrophic Lateral Sclerosis?

by Christina Vasilopoulou, Andrew P. Morris, George Giannakopoulos, Stephanie Duguez and William Duddy

J. Pers. Med. 2020, 10(4), 247; https://doi.org/10.3390/jpm10040247 - 26 Nov 2020

Cited by 13 | Viewed by 4849

Abstract

Amyotrophic Lateral Sclerosis (ALS) is the most common late-onset motor neuron disorder, but our current knowledge of the molecular mechanisms and pathways underlying this disease remain elusive. This review (1) systematically identifies machine learning studies aimed at the understanding of the genetic architecture [...] Read more.

Amyotrophic Lateral Sclerosis (ALS) is the most common late-onset motor neuron disorder, but our current knowledge of the molecular mechanisms and pathways underlying this disease remain elusive. This review (1) systematically identifies machine learning studies aimed at the understanding of the genetic architecture of ALS, (2) outlines the main challenges faced and compares the different approaches that have been used to confront them, and (3) compares the experimental designs and results produced by those approaches and describes their reproducibility in terms of biological results and the performances of the machine learning models. The majority of the collected studies incorporated prior knowledge of ALS into their feature selection approaches, and trained their machine learning models using genomic data combined with other types of mined knowledge including functional associations, protein-protein interactions, disease/tissue-specific information, epigenetic data, and known ALS phenotype-genotype associations. The importance of incorporating gene-gene interactions and cis-regulatory elements into the experimental design of future ALS machine learning studies is highlighted. Lastly, it is suggested that future advances in the genomic and machine learning fields will bring about a better understanding of ALS genetic architecture, and enable improved personalized approaches to this and other devastating and complex diseases. Full article

(This article belongs to the Special Issue Understanding Neuromuscular Health and Disease: Advances in Genetics, Omics, and Molecular Function)

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15 pages, 1361 KiB

Open AccessReview

Modelling Neuromuscular Diseases in the Age of Precision Medicine

by Alfina A. Speciale, Ruth Ellerington, Thomas Goedert and Carlo Rinaldi

J. Pers. Med. 2020, 10(4), 178; https://doi.org/10.3390/jpm10040178 - 17 Oct 2020

Cited by 7 | Viewed by 4253

Abstract

Advances in knowledge resulting from the sequencing of the human genome, coupled with technological developments and a deeper understanding of disease mechanisms of pathogenesis are paving the way for a growing role of precision medicine in the treatment of a number of human [...] Read more.

Advances in knowledge resulting from the sequencing of the human genome, coupled with technological developments and a deeper understanding of disease mechanisms of pathogenesis are paving the way for a growing role of precision medicine in the treatment of a number of human conditions. The goal of precision medicine is to identify and deliver effective therapeutic approaches based on patients’ genetic, environmental, and lifestyle factors. With the exception of cancer, neurological diseases provide the most promising opportunity to achieve treatment personalisation, mainly because of accelerated progress in gene discovery, deep clinical phenotyping, and biomarker availability. Developing reproducible, predictable and reliable disease models will be key to the rapid delivery of the anticipated benefits of precision medicine. Here we summarize the current state of the art of preclinical models for neuromuscular diseases, with particular focus on their use and limitations to predict safety and efficacy treatment outcomes in clinical trials. Full article

(This article belongs to the Special Issue Understanding Neuromuscular Health and Disease: Advances in Genetics, Omics, and Molecular Function)

11 pages, 243 KiB

Open AccessFeature PaperReview

Advances in Genetic Characterization and Genotype–Phenotype Correlation of Duchenne and Becker Muscular Dystrophy in the Personalized Medicine Era

by Omar Sheikh and Toshifumi Yokota

J. Pers. Med. 2020, 10(3), 111; https://doi.org/10.3390/jpm10030111 - 3 Sep 2020

Cited by 20 | Viewed by 6064

Abstract

Currently, Duchenne muscular dystrophy (DMD) and the related condition Becker muscular dystrophy (BMD) can be usually diagnosed using physical examination and genetic testing. While BMD features partially functional dystrophin protein due to in-frame mutations, DMD largely features no dystrophin production because of out-of-frame [...] Read more.

Currently, Duchenne muscular dystrophy (DMD) and the related condition Becker muscular dystrophy (BMD) can be usually diagnosed using physical examination and genetic testing. While BMD features partially functional dystrophin protein due to in-frame mutations, DMD largely features no dystrophin production because of out-of-frame mutations. However, BMD can feature a range of phenotypes from mild to borderline DMD, indicating a complex genotype–phenotype relationship. Despite two mutational hot spots in dystrophin, mutations can arise across the gene. The use of multiplex ligation amplification (MLPA) can easily assess the copy number of all exons, while next-generation sequencing (NGS) can uncover novel or confirm hard-to-detect mutations. Exon-skipping therapy, which targets specific regions of the dystrophin gene based on a patient’s mutation, is an especially prominent example of personalized medicine for DMD. To maximize the benefit of exon-skipping therapies, accurate genetic diagnosis and characterization including genotype–phenotype correlation studies are becoming increasingly important. In this article, we present the recent progress in the collection of mutational data and optimization of exon-skipping therapy for DMD/BMD. Full article

(This article belongs to the Special Issue Understanding Neuromuscular Health and Disease: Advances in Genetics, Omics, and Molecular Function)

34 pages, 3871 KiB

Open AccessReview

Molecular and Cellular Mechanisms Affected in ALS

by Laura Le Gall, Ekene Anakor, Owen Connolly, Udaya Geetha Vijayakumar, William J. Duddy and Stephanie Duguez

J. Pers. Med. 2020, 10(3), 101; https://doi.org/10.3390/jpm10030101 - 25 Aug 2020

Cited by 91 | Viewed by 11832

Abstract

Amyotrophic lateral sclerosis (ALS) is a terminal late-onset condition characterized by the loss of upper and lower motor neurons. Mutations in more than 30 genes are associated to the disease, but these explain only ~20% of cases. The molecular functions of these genes [...] Read more.

Amyotrophic lateral sclerosis (ALS) is a terminal late-onset condition characterized by the loss of upper and lower motor neurons. Mutations in more than 30 genes are associated to the disease, but these explain only ~20% of cases. The molecular functions of these genes implicate a wide range of cellular processes in ALS pathology, a cohesive understanding of which may provide clues to common molecular mechanisms across both familial (inherited) and sporadic cases and could be key to the development of effective therapeutic approaches. Here, the different pathways that have been investigated in ALS are summarized, discussing in detail: mitochondrial dysfunction, oxidative stress, axonal transport dysregulation, glutamate excitotoxicity, endosomal and vesicular transport impairment, impaired protein homeostasis, and aberrant RNA metabolism. This review considers the mechanistic roles of ALS-associated genes in pathology, viewed through the prism of shared molecular pathways. Full article

(This article belongs to the Special Issue Understanding Neuromuscular Health and Disease: Advances in Genetics, Omics, and Molecular Function)

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23 pages, 510 KiB

Open AccessReview

The Identification of Novel Biomarkers Is Required to Improve Adult SMA Patient Stratification, Diagnosis and Treatment

by Piera Smeriglio, Paul Langard, Giorgia Querin and Maria Grazia Biferi

J. Pers. Med. 2020, 10(3), 75; https://doi.org/10.3390/jpm10030075 - 29 Jul 2020

Cited by 32 | Viewed by 7631

Abstract

Spinal muscular atrophy (SMA) is currently classified into five different subtypes, from the most severe (type 0) to the mildest (type 4) depending on age at onset, best motor function achieved, and copy number of the SMN2 gene. The two recent approved treatments [...] Read more.

Spinal muscular atrophy (SMA) is currently classified into five different subtypes, from the most severe (type 0) to the mildest (type 4) depending on age at onset, best motor function achieved, and copy number of the SMN2 gene. The two recent approved treatments for SMA patients revolutionized their life quality and perspectives. However, upon treatment with Nusinersen, the most widely administered therapy up to date, a high degree of variability in therapeutic response was observed in adult SMA patients. These data, together with the lack of natural history information and the wide spectrum of disease phenotypes, suggest that further efforts are needed to develop precision medicine approaches for all SMA patients. Here, we compile the current methods for functional evaluation of adult SMA patients treated with Nusinersen. We also present an overview of the known molecular changes underpinning disease heterogeneity. We finally highlight the need for novel techniques, i.e., -omics approaches, to capture phenotypic differences and to understand the biological signature in order to revise the disease classification and device personalized treatments. Full article

(This article belongs to the Special Issue Understanding Neuromuscular Health and Disease: Advances in Genetics, Omics, and Molecular Function)

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12 pages, 598 KiB

Open AccessReview

DUX4 Expression in FSHD Muscles: Focus on Its mRNA Regulation

by Eva Sidlauskaite, Laura Le Gall, Virginie Mariot and Julie Dumonceaux

J. Pers. Med. 2020, 10(3), 73; https://doi.org/10.3390/jpm10030073 - 28 Jul 2020

Cited by 12 | Viewed by 5026

Abstract

Facioscapulohumeral dystrophy (FSHD) is the most frequent muscular disease in adults. FSHD is characterized by a weakness and atrophy of a specific set of muscles located in the face, the shoulder, and the upper arms. FSHD patients may present different genetic defects, but [...] Read more.

Facioscapulohumeral dystrophy (FSHD) is the most frequent muscular disease in adults. FSHD is characterized by a weakness and atrophy of a specific set of muscles located in the face, the shoulder, and the upper arms. FSHD patients may present different genetic defects, but they all present epigenetic alterations of the D4Z4 array located on the subtelomeric part of chromosome 4, leading to chromatin relaxation and, ultimately, to the aberrant expression of one gene called DUX4. Once expressed, DUX4 triggers a cascade of deleterious events, eventually leading to muscle dysfunction and cell death. Here, we review studies on DUX4 expression in skeletal muscle to determine the genetic/epigenetic factors and regulatory proteins governing DUX4 expression, with particular attention to the different transcripts and their very low expression in muscle. Full article

(This article belongs to the Special Issue Understanding Neuromuscular Health and Disease: Advances in Genetics, Omics, and Molecular Function)

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27 pages, 1880 KiB

Open AccessReview

A Systematic Review of Genotype–Phenotype Correlation across Cohorts Having Causal Mutations of Different Genes in ALS

by Owen Connolly, Laura Le Gall, Gavin McCluskey, Colette G Donaghy, William J Duddy and Stephanie Duguez

J. Pers. Med. 2020, 10(3), 58; https://doi.org/10.3390/jpm10030058 - 29 Jun 2020

Cited by 36 | Viewed by 11162

Abstract

Amyotrophic lateral sclerosis is a rare and fatal neurodegenerative disease characterised by progressive deterioration of upper and lower motor neurons that eventually culminates in severe muscle atrophy, respiratory failure and death. There is a concerning lack of understanding regarding the mechanisms that lead [...] Read more.

Amyotrophic lateral sclerosis is a rare and fatal neurodegenerative disease characterised by progressive deterioration of upper and lower motor neurons that eventually culminates in severe muscle atrophy, respiratory failure and death. There is a concerning lack of understanding regarding the mechanisms that lead to the onset of ALS and as a result there are no reliable biomarkers that aid in the early detection of the disease nor is there an effective treatment. This review first considers the clinical phenotypes associated with ALS, and discusses the broad categorisation of ALS and ALS-mimic diseases into upper and lower motor neuron diseases, before focusing on the genetic aetiology of ALS and considering the potential relationship of mutations of different genes to variations in phenotype. For this purpose, a systematic review is conducted collating data from 107 original published clinical studies on monogenic forms of the disease, surveying the age and site of onset, disease duration and motor neuron involvement. The collected data highlight the complexity of the disease’s genotype–phenotype relationship, and thus the need for a nuanced approach to the development of clinical assays and therapeutics. Full article

(This article belongs to the Special Issue Understanding Neuromuscular Health and Disease: Advances in Genetics, Omics, and Molecular Function)

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9 pages, 222 KiB

Open AccessReview

An Omics View of Emery–Dreifuss Muscular Dystrophy

by Nicolas Vignier and Antoine Muchir

J. Pers. Med. 2020, 10(2), 50; https://doi.org/10.3390/jpm10020050 - 15 Jun 2020

Cited by 3 | Viewed by 4609

Abstract

Recent progress in Omics technologies has started to empower personalized healthcare development at a thorough biomolecular level. Omics have subsidized medical breakthroughs that have started to enter clinical proceedings. The use of this scientific know-how has surfaced as a way to provide a [...] Read more.

Recent progress in Omics technologies has started to empower personalized healthcare development at a thorough biomolecular level. Omics have subsidized medical breakthroughs that have started to enter clinical proceedings. The use of this scientific know-how has surfaced as a way to provide a more far-reaching view of the biological mechanisms behind diseases. This review will focus on the discoveries made using Omics and the utility of these approaches for Emery–Dreifuss muscular dystrophy. Full article

(This article belongs to the Special Issue Understanding Neuromuscular Health and Disease: Advances in Genetics, Omics, and Molecular Function)

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