Introduction:
Corticosteroid treatment is the standard of care in Duchenne muscular dystrophy (DMD), but the optimal age to initiate treatment and dosage pattern remain a matter of discussion.
...Methods:
We performed a long‐term study of alternate‐day corticosteroids in five 2‐ to 4‐year‐old DMD patients. The primary outcome measure was prolongation of the ability to walk.
Results:
One patient lost ambulation at age 10. Four patients, aged 16 to 18 were fully ambulant, and 3 of them could still climb stairs. Respiratory function was moderately reduced in 2. Left ventricular ejection fraction was > 45%. Short stature and delayed puberty were the most relevant side effects. Although the negative impact of corticosteroid treatment on growth rate remained their major concern, parents and patients stated that they preferred corticosteroid therapy.
Conclusions:
Long‐term corticosteroid treatment is effective in prolonging function but not in recovering lost function, and its early use seems appropriate. Muscle Nerve 45: 796–802, 2012
Ullrich congenital muscular dystrophy and Bethlem myopathy are skeletal muscle diseases that are due to mutations in the genes encoding collagen VI, an extracellular matrix protein forming a ...microfibrillar network that is particularly prominent in the endomysium of skeletal muscle. Myoblasts from patients affected by Ullrich congenital muscular dystrophy display functional and ultrastructural mitochondrial alterations and increased apoptosis due to inappropriate opening of the permeability transition pore, a mitochondrial inner membrane channel. These alterations could be normalized by treatment with cyclosporin A, a widely used immunosuppressant that desensitizes the permeability transition pore independently of calcineurin inhibition. Here, we report the results of an open pilot trial with cyclosporin A in five patients with collagen VI myopathies. Before treatment, all patients displayed mitochondrial dysfunction and increased frequency of apoptosis, as determined in muscle biopsies. Both of these pathologic signs were largely normalized after 1 month of oral cyclosporin A administration, which also increased muscle regeneration. These findings demonstrate that collagen VI myopathies can be effectively treated with drugs acting on the pathogenic mechanism downstream of the genetic lesion, and they represent an important proof of principle for the potential therapy of genetic diseases.
Objectives We sought to describe the diagnostic work-up, phenotype, and long-term evolution of dilated cardiomyopathy (DCM) associated with Dystrophin (DYS) defects. Background X-linked DCM ...associated with DYS defects can be clinically indistinguishable from other types of DCM. Methods The series comprises 436 consecutive male patients diagnosed with DCM. Patients underwent endomyocardial biopsy (EMB). Genetic testing employed multiplex polymerase chain reaction and multiple ligation dependent probe assay for deletions and direct sequencing of the 79 exons and flanking regions of the gene for point mutations or small rearrangements. Results We identified DYS defects in 34 of 436 patients (7.8%) (onset age 34 ± 11 years, age range 17 to 54 years); 30 had proven X-linked inheritance. The 2 phenotypes included DCM with mild skeletal myopathy and/or increased serum creatine phosphokinase (n = 28) or DCM only (n = 6). The EMB showed defective dystrophin immunostain. The DYS defects consisted of 21 in-frame deletions and 11 out-of-frame deletions as well as 1 stop and 1 splice-site mutation. During a median follow-up of 60 months (interquartile range: 11.25 to 101.34 months) we observed 17 events, all related to heart failure (HF) (median event-free survival: 83.5 months). Eight patients (23%) underwent transplantation, and 9 (26%) died of HF while waiting for transplantation. Eight patients received an implantable cardioverter-defibrillator, although none had device intervention during a median follow-up of 14 months (interquartile range: 5 to 25 months). No patient died suddenly, suffered syncope, or developed life-threatening ventricular arrhythmias. Conclusions DYS- related DCM should be suspected in male patients with increased serum creatine phosphokinase (82%) and X-linked inheritance. The disease shows a high risk of end-stage HF but a lower risk of life-threatening arrhythmias.
Duchenne muscular dystrophy (DMD) is a rare neuromuscular disease caused by pathogenic variations in the
gene. There is a need for robust DMD biomarkers for diagnostic screening and to aid therapy ...monitoring. Creatine kinase, to date, is the only routinely used blood biomarker for DMD, although it lacks specificity and does not correlate with disease severity. To fill this critical gap, we present here novel data about dystrophin protein fragments detected in human plasma by a suspension bead immunoassay using two validated anti-dystrophin-specific antibodies. Using both antibodies, a reduction of the dystrophin signal is detected in a small cohort of plasma samples from DMD patients when compared to healthy controls, female carriers, and other neuromuscular diseases. We also demonstrate the detection of dystrophin protein by an antibody-independent method using targeted liquid chromatography mass spectrometry. This last assay detects three different dystrophin peptides in all healthy individuals analysed and supports our finding that dystrophin protein is detectable in plasma. The results of our proof-of-concept study encourage further studies in larger sample cohorts to investigate the value of dystrophin protein as a low invasive blood biomarker for diagnostic screening and clinical monitoring of DMD.
Duchenne muscular dystrophy (DMD) is caused by pathogenic variants in the DMD gene leading to the lack of dystrophin. Variability in the disease course suggests that other factors influence disease ...progression. With this study we aimed to identify genetic factors that may account for some of the variability in the clinical presentation. We compared whole-exome sequencing (WES) data in 27 DMD patients with extreme phenotypes to identify candidate variants that could affect disease progression. Validation of the candidate SNPs was performed in two independent cohorts including 301 (BIO-NMD cohort) and 109 (CINRG cohort of European ancestry) DMD patients, respectively. Variants in the Tctex1 domain containing 1 (TCTEX1D1) gene on chromosome 1 were associated with age of ambulation loss. The minor alleles of two independent variants, known to affect TCTEX1D1 coding sequence and induce skipping of its exon 4, were associated with earlier loss of ambulation. Our data show that disease progression of DMD is affected by a new locus on chromosome 1 and demonstrate the possibility to identify genetic modifiers in rare diseases by studying WES data in patients with extreme phenotypes followed by multiple layers of validation.
Incontinentia pigmenti (IP; Online Mendelian Inheritance in Man catalog #308300) is an X-linked dominant ectodermal disorder caused by mutations of the inhibitor of κ polypeptide gene enchancer in B ...cells, kinase γ (
)/ nuclear factor κB, essential modulator (
) gene. Hemizygous
loss-of-function (LoF) mutations are lethal in males, thus patients are female, and the disease is always transmitted from an IP-affected mother to her daughter. We present 2 families with father-to-daughter transmission of IP and provide for the first time molecular evidence that the combination of somatic and germ-line mosaicism for
loss of function mutations in IP males resulted in the transmission of the disease to a female child. We searched for the
mutant allele in blood, urine, skin, and sperm DNA and found that the 2 fathers were somatic and germ-line mosaics for the p.Gln132×mutation or the exon 4-10 deletion of
, respectively. The highest level of
mutant cells was detected in the sperm, which might explain the recurrence of the disease. We therefore recommend careful clinical evaluation in IP male cases and the genetic investigation in sperm DNA to ensure correct genetic counseling and prevent the risk of paternal transmission of IP.
The genetic diagnostics of inherited neuromuscular diseases (NMDs) is challenging due to their clinical and genetic heterogeneity. We launched an online survey within the EURO-NMD European Reference ...Network (ERN) to collect information about the availability/distribution of genetic testing across 61 ERN health care providers (HCPs). A 17 items questionnaire was designed to address methods used, the number of genetic tests available, the clinical pathway to access genetic testing, the use of next-generation sequencing (NGS) and participation to quality assessment schemes (QAs). A remarkable number of HCPs (49%) offers greater than or equal to 500 genetic tests per year, 43,6% offers 100-500 genetic tests per year, and 7,2% less than or equal to 100 per year. NGS is used by 94% of centres, Sanger sequencing by 84%, MLPA by 66% and Southern blotting by 36%. The majority of centres (60%) offer NGS for all patients that fulfil criteria for NMD of genetic origin. Pipelines for NGS vary amongst centres, even within the same national system. Referral of patients to genetic laboratories by specialists was frequently reported (58%), and 65% of centres participates in genetic testing QAs. We specifically evaluated how many centres cover SMA, DMD, Pompe, LGMDs, and TTR genes/diseases genetic diagnosis, since these rare diseases benefit from personalised therapies. We used the Orphanet EUGT numbers, provided by 82% of HCPs. SMA, DMD, LGMD, TTR and GAA genes are covered by EUGTs although with different numbers and modalities. The number of genetic tests for NMDs offered across HCPs National Health systems is quite high, including routine techniques and NGS. The number and type of tests offered and the clinical practices differ among centres. We provided evidence that survey tools might be useful to learn about the state-of-the-art of ERN health-related activities and to foster harmonisation and standardisation of the complex care for the rare disease patients in the EU.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Newborn screening for treatable disorders is one of the great public health success stories of the twentieth century worldwide. This commentary examines the potential use of a new technology, next ...generation sequencing, in newborn screening through the lens of the Wilson and Jungner criteria. Each of the ten criteria are examined to show how they might be applied by programmes using genomic sequencing as a screening tool. While there are obvious advantages to a method that can examine all disease-causing genes in a single assay at an ever-diminishing cost, implementation of genomic sequencing at scale presents numerous challenges, some which are intrinsic to screening for rare disease and some specifically linked to genomics-led screening. In addition to questions specific to routine screening considerations, the ethical, communication, data management, legal, and social implications of genomic screening programmes require consideration.
Following the reverse genetics strategy developed in the 1980s to pioneer the identification of disease genes, genome(s) sequencing has opened the era of genomics medicine. The human genome project ...has led to an innumerable series of applications of omics sciences on global health, from which rare diseases (RDs) have greatly benefited. This has propelled the scientific community towards major breakthroughs in disease genes discovery, in technical innovations in bioinformatics, and in the development of patients' data registries and omics repositories where sequencing data are stored. Rare diseases were the first diseases where nucleic acid-based therapies have been applied. Gene therapy, molecular therapy using RNA constructs, and medicines modulating transcription or translation mechanisms have been developed for RD patients and started a new era of medical science breakthroughs. These achievements together with optimization of highly scalable next generation sequencing strategies now allow movement towards genetic newborn screening. Its applications in human health will be challenging, while expected to positively impact the RD diagnostic journey. Genetic newborn screening brings many complexities to be solved, technical, strategic, ethical, and legal, which the RD community is committed to address. Genetic newborn screening initiatives are therefore blossoming worldwide, and the EU-IMI framework has funded the project Screen4Care. This large Consortium will apply a dual genetic and digital strategy to design a comprehensive genetic newborn screening framework to be possibly translated into the future health care.
Non-coding RNAs in muscle dystrophies Erriquez, Daniela; Perini, Giovanni; Ferlini, Alessandra
International Journal of Molecular Sciences,
09/2013, Letnik:
14, Številka:
10
Journal Article, Book Review
Recenzirano
Odprti dostop
ncRNAs are the most recently identified class of regulatory RNAs with vital functions in gene expression regulation and cell development. Among the variety of roles they play, their involvement in ...human diseases has opened new avenues of research towards the discovery and development of novel therapeutic approaches. Important data come from the field of hereditary muscle dystrophies, like Duchenne muscle dystrophy and Myotonic dystrophies, rare diseases affecting 1 in 7000-15,000 newborns and is characterized by severe to mild muscle weakness associated with cardiac involvement. Novel therapeutic approaches are now ongoing for these diseases, also based on splicing modulation. In this review we provide an overview about ncRNAs and their behavior in muscular dystrophy and explore their links with diagnosis, prognosis and treatments, highlighting the role of regulatory RNAs in these pathologies.
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