RESUMEN
Detection of structural variants (SVs) is currently biased toward those that alter copy number. The relative contribution of inversions toward genetic disease is unclear. In this study, we analyzed genome sequencing data for 33,924 families with rare disease from the 100,000 Genomes Project. From a database hosting >500 million SVs, we focused on 351 genes where haploinsufficiency is a confirmed disease mechanism and identified 47 ultra-rare rearrangements that included an inversion (24 bp to 36.4 Mb, 20/47 de novo). Validation utilized a number of orthogonal approaches, including retrospective exome analysis. RNA-seq data supported the respective diagnoses for six participants. Phenotypic blending was apparent in four probands. Diagnostic odysseys were a common theme (>50 years for one individual), and targeted analysis for the specific gene had already been performed for 30% of these individuals but with no findings. We provide formal confirmation of a European founder origin for an intragenic MSH2 inversion. For two individuals with complex SVs involving the MECP2 mutational hotspot, ambiguous SV structures were resolved using long-read sequencing, influencing clinical interpretation. A de novo inversion of HOXD11-13 was uncovered in a family with Kantaputra-type mesomelic dysplasia. Lastly, a complex translocation disrupting APC and involving nine rearranged segments confirmed a clinical diagnosis for three family members and resolved a conundrum for a sibling with a single polyp. Overall, inversions play a small but notable role in rare disease, likely explaining the etiology in around 1/750 families across heterogeneous clinical cohorts.
Asunto(s)
Inversión Cromosómica , Enfermedades Raras , Humanos , Enfermedades Raras/genética , Masculino , Femenino , Inversión Cromosómica/genética , Linaje , Genoma Humano , Secuenciación Completa del Genoma , Proteína 2 de Unión a Metil-CpG/genética , Mutación , Proteínas de Homeodominio/genética , Persona de Mediana EdadRESUMEN
BACKGROUND: Amyotrophic lateral sclerosis (ALS) is a neurodegenerative disease of the upper and lower motor neurons with varying ages of onset, progression and pathomechanisms. Monogenic childhood-onset ALS, although rare, forms an important subgroup of ALS. We recently reported specific SPTLC1 variants resulting in sphingolipid overproduction as a cause for juvenile ALS. Here, we report six patients from six independent families with a recurrent, de novo, heterozygous variant in SPTLC2 c.778G>A [p.Glu260Lys] manifesting with juvenile ALS. METHODS: Clinical examination of the patients along with ancillary and genetic testing, followed by biochemical investigation of patients' blood and fibroblasts, was performed. RESULTS: All patients presented with early-childhood-onset progressive weakness, with signs and symptoms of upper and lower motor neuron degeneration in multiple myotomes, without sensory neuropathy. These findings were supported on ancillary testing including nerve conduction studies and electromyography, muscle biopsies and muscle ultrasound studies. Biochemical investigations in plasma and fibroblasts showed elevated levels of ceramides and unrestrained de novo sphingolipid synthesis. Our studies indicate that SPTLC2 variant [c.778G>A, p.Glu260Lys] acts distinctly from hereditary sensory and autonomic neuropathy (HSAN)-causing SPTLC2 variants by causing excess canonical sphingolipid biosynthesis, similar to the recently reported SPTLC1 ALS associated pathogenic variants. Our studies also indicate that serine supplementation, which is a therapeutic in SPTLC1 and SPTCL2-associated HSAN, is expected to exacerbate the excess sphingolipid synthesis in serine palmitoyltransferase (SPT)-associated ALS. CONCLUSIONS: SPTLC2 is the second SPT-associated gene that underlies monogenic, juvenile ALS and further establishes alterations of sphingolipid metabolism in motor neuron disease pathogenesis. Our findings also have important therapeutic implications: serine supplementation must be avoided in SPT-associated ALS, as it is expected to drive pathogenesis further.
Asunto(s)
Esclerosis Amiotrófica Lateral , Neuropatías Hereditarias Sensoriales y Autónomas , Enfermedades Neurodegenerativas , Niño , Humanos , Esclerosis Amiotrófica Lateral/genética , Esfingolípidos , Serina C-Palmitoiltransferasa/genética , Serina C-Palmitoiltransferasa/metabolismo , Neuropatías Hereditarias Sensoriales y Autónomas/genética , SerinaRESUMEN
Cerebral palsy (CP) causes neurological disability in early childhood. Hypoxic-ischaemic injury plays a major role in its aetiology, nevertheless, genetic and epigenetic factors may contribute to the clinical presentation. Mutations in ADD3 (encoding γ-adducin) gene have been described in a monogenic form of spastic quadriplegic cerebral palsy (OMIM 601568). We studied a 16-year-old male with spastic diplegia. Several investigations including neurometabolic testing, brain and spine magnetic resonance imaging (MRI) and CGH-Array were normal. Further, clinical genetics assessment and whole exome sequencing (WES) gave the diagnosis. We generated an animal model using Drosophila to study the effects of γ-adducin loss and gain of function. WES revealed a biallelic variant in the ADD3 gene, NM_016824.5(ADD3): c.1100G > A, p.(Gly367Asp). Mutations in this gene have been described as an ultra-rare autosomal recessive, which is a known form of inherited cerebral palsy. Molecular modelling suggests that this mutation leads to a loss of structural integrity of γ-adducin and is therefore expected to result in a decreased level of functional protein. Pan-neuronal over-expression or knock-down of the Drosophila ortholog of ADD3 called hts caused a reduction of life span and impaired locomotion thereby phenocopying aspects of the human disease. Our animal experiments present a starting point to understand the biological processes underpinning the clinical phenotype and pathogenic mechanisms, to gain insights into potential future methods for treating or preventing ADD3 related spastic quadriplegic cerebral palsy.
Asunto(s)
Parálisis Cerebral , Paraparesia Espástica , Paraplejía Espástica Hereditaria , Animales , Masculino , Preescolar , Humanos , Adolescente , Drosophila/genética , Paraparesia Espástica/genética , Espasticidad Muscular , Mutación , Paraplejía Espástica Hereditaria/genética , Proteínas de Unión a Calmodulina/genéticaRESUMEN
We present eight families with arthrogryposis multiplex congenita and myopathy bearing a TTN intron 213 extended splice-site variant (NM_001267550.1:c.39974-11T>G), inherited in trans with a second pathogenic TTN variant. Muscle-derived RNA studies of three individuals confirmed mis-splicing induced by the c.39974-11T>G variant; in-frame exon 214 skipping or use of a cryptic 3' splice-site effecting a frameshift. Confounding interpretation of pathogenicity is the absence of exons 213-217 within the described skeletal muscle TTN N2A isoform. However, RNA-sequencing from 365 adult human gastrocnemius samples revealed that 56% specimens predominantly include exons 213-217 in TTN transcripts (inclusion rate ≥66%). Further, RNA-sequencing of five fetal muscle samples confirmed that 4/5 specimens predominantly include exons 213-217 (fifth sample inclusion rate 57%). Contractures improved significantly with age for four individuals, which may be linked to decreased expression of pathogenic fetal transcripts. Our study extends emerging evidence supporting a vital developmental role for TTN isoforms containing metatranscript-only exons.
Asunto(s)
Empalme Alternativo , Artrogriposis/diagnóstico , Artrogriposis/genética , Conectina/genética , Genes Recesivos , Predisposición Genética a la Enfermedad , Enfermedades Musculares/diagnóstico , Enfermedades Musculares/genética , Niño , Preescolar , Femenino , Estudios de Asociación Genética , Humanos , Lactante , Masculino , Mutación , Linaje , Fenotipo , RadiografíaRESUMEN
The ß-tropomyosin gene encodes a component of the sarcomeric thin filament. Rod-shaped dimers of tropomyosin regulate actin-myosin interactions and ß-tropomyosin mutations have been associated with nemaline myopathy, cap myopathy, Escobar syndrome and distal arthrogryposis types 1A and 2B. In this study, we expand the allelic spectrum of ß-tropomyosin-related myopathies through the identification of a novel ß-tropomyosin mutation in two clinical contexts not previously associated with ß-tropomyosin. The first clinical phenotype is core-rod myopathy, with a ß-tropomyosin mutation uncovered by whole exome sequencing in a family with autosomal dominant distal myopathy and muscle biopsy features of both minicores and nemaline rods. The second phenotype, observed in four unrelated families, is autosomal dominant trismus-pseudocamptodactyly syndrome (distal arthrogryposis type 7; previously associated exclusively with myosin heavy chain 8 mutations). In all four families, the mutation identified was a novel 3-bp in-frame deletion (c.20_22del) that results in deletion of a conserved lysine at the seventh amino acid position (p.K7del). This is the first mutation identified in the extreme N-terminus of ß-tropomyosin. To understand the potential pathogenic mechanism(s) underlying this mutation, we performed both computational analysis and in vivo modelling. Our theoretical model predicts that the mutation disrupts the N-terminus of the α-helices of dimeric ß-tropomyosin, a change predicted to alter protein-protein binding between ß-tropomyosin and other molecules and to disturb head-to-tail polymerization of ß-tropomyosin dimers. To create an in vivo model, we expressed wild-type or p.K7del ß-tropomyosin in the developing zebrafish. p.K7del ß-tropomyosin fails to localize properly within the thin filament compartment and its expression alters sarcomere length, suggesting that the mutation interferes with head-to-tail ß-tropomyosin polymerization and with overall sarcomeric structure. We describe a novel ß-tropomyosin mutation, two clinical-histopathological phenotypes not previously associated with ß-tropomyosin and pathogenic data from the first animal model of ß-tropomyosin-related myopathies.
Asunto(s)
Lisina/genética , Enfermedades Musculares/diagnóstico , Enfermedades Musculares/genética , Eliminación de Secuencia , Tropomiosina/genética , Adolescente , Adulto , Secuencia de Aminoácidos , Animales , Niño , Femenino , Humanos , Masculino , Persona de Mediana Edad , Datos de Secuencia Molecular , Enfermedades Musculares/patología , Tropomiosina/química , Adulto Joven , Pez CebraRESUMEN
Spinal muscular atrophy (SMA) is an autosomal recessive disorder with progressive muscle atrophy and weakness, caused by biallelic mutations in the survival motor neuron 1 (SNM1) gene. Onasemnogene abeparvovec (OA) is an approved gene replacement therapy for patients with SMA. We report on two patients with SMA type 1, weighing 20 kg, previously treated with Nusinersen, who received OA infusion at 7 years of age. To our knowledge, these two patients are the heaviest treated in the real-world and we describe their different courses after gene therapy, including liver impairment requiring long-term steroid treatment and additional immunosuppression, with only transitory improvement in functional outcomes. Our cases illustrate how careful risk-benefit consideration is required in treating older and heavier SMA patients with OA, especially in view of the multiple treatment choices available for older patients with SMA.
RESUMEN
Background: Spinal muscular atrophy (SMA) is a progressive neuromuscular disease caused by mutations in Survival motor neuron 1 (SMN1) gene, leading to reduction in survival motor neuron protein (SMN), key for motor neuron survival and function in the brainstem and spinal cord. Risdiplam is an orally administered SMN2-splicing modifier which increases production of functional SMN protein. Risdiplam was offered in the UK under early access to medicines scheme (EAMS) to SMA type 1 and 2 patients aged 2 months and older, not suitable for authorised treatments from September 2020 to December 2021. Objective: To describe the largest paediatric European real-world set of data on patients' characteristics and short-term safety for risdiplam in Great Britain through EAMS. Methods: We collated data from SMA REACH UK a national clinical and research network for all patients enrolled onto EAMS and assessed all submitted adverse events. Results: Of the 92 patients; 78% were Type 2 SMA, mean age 10.9 years, range 0-17 years. 56 were treatment naïve, 33 previously treated; of these 25 had received nusinersen, 3 previous treatment unknown. Sixty adverse events (AEs) were reported occurring in 34 patients. The commonest were respiratory tract infections and gastrointestinal disturbance. Four life-threatening events were reported with 2 deaths and permanent cessation of risdiplam in 3 patients.Overall, 38/60 AEs were considered unrelated to risdiplam, 10/60 related to risdiplam and for 12/60 causality not specified. Conclusions: This study found a safety profile similar to clinical trials with no new safety concerns identified. With the restricted eligibility of onasemnogene abeparvovec and complications of nusinersen administration, EAMS allowed access or continued treatment to naïve patients or patients no longer suitable for approved medications. Collection of longitudinal data for this complex population is needed, to provide greater insights into risdiplam's role in addressing patients' needs into the future.
Asunto(s)
Compuestos Azo , Atrofia Muscular Espinal , Atrofias Musculares Espinales de la Infancia , Humanos , Niño , Recién Nacido , Lactante , Preescolar , Adolescente , Reino Unido , Atrofia Muscular Espinal/tratamiento farmacológico , Atrofia Muscular Espinal/genética , Atrofias Musculares Espinales de la Infancia/tratamiento farmacológico , Pirimidinas/efectos adversosRESUMEN
Background and Objectives: Nusinersen has shown significant functional motor benefit in the milder types of spinal muscular atrophy (SMA). Less is known on the respiratory outcomes in patients with nusinersen-treated SMA. The aim of this study was to describe changes in respiratory function in pediatric patients with SMA type 2 and 3 on regular treatment with nusinersen within the iSMAc international cohort and to compare their trajectory with the natural history (NH) data published by the consortium in 2020. Methods: This is a 5-year retrospective observational study of pediatric SMA type 2 and nonambulant type 3 (age ≤18 years) treated with nusinersen. The primary objective was to compare the slopes of decline in forced vital capacity % predicted (FVC% pred.), FVC, and age when FVC dropped below 60% between the treated patients and a control group from the natural history cohort. Data on peak cough flow and the use of noninvasive ventilation (NIV) and cough assist were collected. Results: Data were available for 69 treated patients, 53 were SMA type 2 and 16 type 3. The mean (SD) age at first injection was 8.5 (3.2) and 9.7 (3.7) years, respectively. The median (interquartile range) treatment duration was 1 (0.7; 1.9) and 1.2 (0.9; 1.9) years, respectively. At the time of the first nusinersen injection, 24 of 52 (46%) patients with SMA type 2 and 2 of 16 (13%) patients with SMA type 3 were on NIV. Forty-three of 53 (81%) and 4 of 16 (25%) patients used cough device. FVC% pred. in treated patients with SMA type 2 declined annually by 2.3% vs 3.9% in NH (p = 0.08) and in treated patients with type 3 by 2.6% vs 3.4% NH (p = 0.59). Patients treated reached FVC <60% later than untreated (12.1 vs 10 years, p = 0.05). A higher percentage of treated vs untreated patients maintained FVC% pred. equal/above their baseline after 12 (65% vs 36%) and 24 (50% vs 24%) months, respectively. NIV use among treated did not significantly change throughout 1-year follow-up. Discussion: This study included the largest real-world cohort of pediatric patients with milder SMA types. The results suggest a positive role of nusinersen in delaying the respiratory decline in patients treated longer than 1 year when compared with natural history. Larger cohorts and longer observation are planned. Classification of Evidence: This study provided Class III evidence that nusinersen slows progression for patients with SMA types 2 and 3 compared with a natural history cohort.
RESUMEN
Background: Real-world data on the efficacy and safety of onasemnogene abeparvovec (OA) in spinal muscular atrophy (SMA) are needed, especially to overcome uncertainties around its use in older and heavier children. This study evaluated the efficacy and safety of OA in patients with SMA type 1 in the UK, including patients ≥2 years old and weighing ≥13.5 kg. Methods: This observational cohort study used data from patients with genetically confirmed SMA type 1 treated with OA between May 2021 and January 2023, at 6 infusion centres in the United Kingdom. Functional outcomes were assessed using age-appropriate functional scales. Safety analyses included review of liver function, platelet count, cardiac assessments, and steroid requirements. Findings: Ninety-nine patients (45 SMA therapy-naïve) were treated with OA (median age at infusion: 10 [range, 0.6-89] months; median weight: 7.86 [range, 3.2-20.2] kg; duration of follow-up: 3-22 months). After OA infusion, mean ± SD change in CHOP-INTEND score was 11.0 ± 10.3 with increased score in 66/78 patients (84.6%); patients aged <6 months had a 13.9 points higher gain in CHOP-INTEND score than patients ≥2 years (95% CI, 6.8-21.0; P < 0.001). Asymptomatic thrombocytopenia (71/99 patients; 71.7%), asymptomatic troponin-I elevation (30/89 patients; 33.7%) and transaminitis (87/99 patients; 87.9%) were reported. No thrombotic microangiopathy was observed. Median steroid treatment duration was 97 (range, 28-548) days with dose doubled in 35/99 patients (35.4%). There were 22.5-fold increased odds of having a transaminase peak >100 U/L (95% CI, 2.3-223.7; P = 0.008) and 21.2-fold increased odds of steroid doubling, as per treatment protocol (95% CI, 2.2-209.2; P = 0.009) in patients weighing ≥13.5 kg versus <8.5 kg. Weight at infusion was positively correlated with steroid treatment duration (r = 0.43; P < 0.001). Worsening transaminitis, despite doubling of oral prednisolone, led to treatment with intravenous methylprednisolone in 5 children. Steroid-sparing immunosuppressants were used in 5 children to enable steroid weaning. Two deaths apparently unrelated to OA were reported. Interpretation: OA led to functional improvements and was well tolerated with no persistent clinical complications, including in older and heavier patients. Funding: Novartis Innovative Therapies AG provided a grant for independent medical writing services.
RESUMEN
BACKGROUND: Mutations in COL4A1 are responsible for a spectrum of clinical phenotypes characterized by neurological, ocular, and renal involvement. Neurological features are the most prominent but as such are rather nonspecific. CASE PRESENTATION: Here, we report three new cases that, like five patients we previously described, show the novel common finding of raised creatine kinase (CK) concentration. CONCLUSION: Raised CK concentration, in addition to intracranial calcification, is to be considered another useful pointer to a final diagnosis of COL4A1-related disease.
Asunto(s)
Encefalopatías/genética , Encefalopatías/metabolismo , Calcinosis/etiología , Colágeno Tipo IV/genética , Creatina Quinasa/metabolismo , Mutación/genética , Adolescente , Adulto , Encefalopatías/patología , Calcinosis/genética , Corteza Cerebral/patología , Niño , Preescolar , Femenino , Humanos , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Fibras Nerviosas Mielínicas/patologíaRESUMEN
Here, we describe a five year old girl with congenital HIV who had a six-week onset of rapidly deteriorating mobility and progressive proximal muscle weakness, associated with a raised Creatine Kinase (CK) level of 4330 U/L [25-200 U/L], subsequently diagnosed with an inflammatory myositis. Potential causes were investigated by paediatric neurology and immunology teams. Her viral load had been undetectable over the preceding two years, excluding a primary HIV myositis. While MRI scanning did not show evidence of definite myositis, a muscle biopsy showed evidence of an inflammatory process, comprising a moderate endomysial, perimysial and perivascular mononuclear (CD8â+âT cell) infiltrate with increased MHC expression. No particular features of dermatomyositis or immune-mediated necrotising myopathy were identified and there were no features of an inclusion body myositis.Given the absence of active HIV infection, the role of anti-retroviral medications was considered. She had had a recent switch in medication, from twice daily Raltegravir (an Integrase Strand Transfer Inhibitor, INSTI) to once daily Dolutegravir (an INSTI) while continuing on an established daily protocol of Abacavir and Lamivudine (Nucleoside Reverse Transcriptase Inhibitors). Changing the Dolutegravir back to Raltegravir, in combination with continuing Lamivudine and Abacavir for two months made no difference to her weakness or CK levels. Moreover, this drug regimen had been well-tolerated over the preceding 19 month period. Changing the anti-retroviral regime completely to a single drug class (Protease Inhibitors) of Ritonavir and Darunavir, resulted in a dramatic improvement in her symptomatology. Within ten days she regained the ability to stand and walk, with a reduction in her CK from 1700 U/L at time of switch to 403 U/L [25-200]. This case highlights the potential risk of developing inflammatory myositis from anti-retrovirals even 19 months into treatment.
Asunto(s)
Antirretrovirales/efectos adversos , Terapia Antirretroviral Altamente Activa/efectos adversos , Infecciones por VIH/tratamiento farmacológico , Miositis/etiología , Preescolar , Femenino , Humanos , Lamivudine/efectos adversos , Raltegravir Potásico/efectos adversos , Carga ViralRESUMEN
Decreased or increased activity of potassium channels caused by loss-of-function and gain-of-function (GOF) variants in the corresponding genes, respectively, underlies a broad spectrum of human disorders affecting the central nervous system, heart, kidney, and other organs. While the association of epilepsy and intellectual disability (ID) with variants affecting function in genes encoding potassium channels is well known, GOF missense variants in K+ channel encoding genes in individuals with syndromic developmental disorders have only recently been recognized. These syndromic phenotypes include Zimmermann-Laband and Temple-Baraitser syndromes, caused by dominant variants in KCNH1, FHEIG syndrome due to dominant variants in KCNK4, and the clinical picture associated with dominant variants in KCNN3. Here we review the presentation of these individuals, including five newly reported with variants in KCNH1 and three additional individuals with KCNN3 variants, all variants likely affecting function. There is notable overlap in the phenotypic findings of these syndromes associated with dominant KCNN3, KCNH1, and KCNK4 variants, sharing developmental delay and/or ID, coarse facial features, gingival enlargement, distal digital hypoplasia, and hypertrichosis. We suggest to combine the phenotypes and define a new subgroup of potassium channelopathies caused by increased K+ conductance, referred to as syndromic neurodevelopmental K+ channelopathies due to dominant variants in KCNH1, KCNK4, or KCNN3.
Asunto(s)
Anomalías Múltiples/genética , Canalopatías/genética , Anomalías Craneofaciales/genética , Canales de Potasio Éter-A-Go-Go/genética , Fibromatosis Gingival/genética , Mutación con Ganancia de Función , Hallux/anomalías , Deformidades Congénitas de la Mano/genética , Discapacidad Intelectual/genética , Uñas Malformadas/genética , Canales de Potasio/genética , Canales de Potasio de Pequeña Conductancia Activados por el Calcio/genética , Pulgar/anomalías , Anomalías Múltiples/patología , Adolescente , Adulto , Canalopatías/patología , Niño , Anomalías Craneofaciales/patología , Femenino , Fibromatosis Gingival/patología , Hallux/patología , Deformidades Congénitas de la Mano/patología , Humanos , Discapacidad Intelectual/patología , Masculino , Uñas Malformadas/patología , Fenotipo , Pulgar/patologíaRESUMEN
OBJECTIVE: To explore the phenotypic spectrum of RHOBTB2-related disorders and specifically to determine whether patients fulfill criteria for alternating hemiplegia of childhood (AHC), we report the clinical features of 11 affected individuals. METHODS: Individuals with RHOBTB2-related disorders were identified through a movement disorder clinic at a specialist pediatric center, with additional cases identified through collaboration with other centers internationally. Clinical data were acquired through retrospective case-note review. RESULTS: Eleven affected patients were identified. All had heterozygous missense variants involving exon 9 of RHOBTB2, confirmed as de novo in 9 cases. All had a complex motor phenotype, including at least 2 different kinds of movement disorder, e.g., ataxia and dystonia. Many patients demonstrated several features fulfilling the criteria for AHC: 10 patients had a movement disorder including paroxysmal elements, and 8 experienced hemiplegic episodes. In contrast to classic AHC, commonly caused by mutations in ATP1A3, these events were reported later only in RHOBTB2 mutation-positive patients from 20 months of age. Seven patients had epilepsy, but of these, 4 patients achieved seizure freedom. All patients had intellectual disability, usually moderate to severe. Other features include episodes of marked skin color change and gastrointestinal symptoms, each in 4 patients. CONCLUSION: Although heterozygous RHOBTB2 mutations were originally described in early infantile epileptic encephalopathy type 64, our study confirms that they account for a more expansive clinical phenotype, including a complex polymorphic movement disorder with paroxysmal elements resembling AHC. RHOBTB2 testing should therefore be considered in patients with an AHC-like phenotype, particularly those negative for ATPA1A3 mutations.
Asunto(s)
Proteínas de Unión al GTP/genética , Hemiplejía/genética , Proteínas Supresoras de Tumor/genética , Adolescente , Niño , Preescolar , Femenino , Humanos , Masculino , Persona de Mediana Edad , Mutación Missense , Fenotipo , Adulto JovenRESUMEN
Pathogenic variants in the Glycyl-tRNA synthetase gene cause the allelic disorders Charcot-Marie-Tooth disease type 2D and distal hereditary motor neuropathy type V. We describe clinical features in 8 unrelated patients found to have Glycyl-tRNA synthetase variants by Next Generation Sequencing. In addition to upper limb predominant symptoms, other presentations included failure to thrive, feeding difficulties and lower limb dominant symptoms. Variability in the age at testing ranged from 14 months to 59 years. The youngest being symptomatic from 3 months and ventilator-dependent. Sequence variants were reported as pathogenic, p.(Glu125Lys), p.(His472Arg); likely pathogenic, p.(His216Arg), p.(Gly327Arg), p.(Lys510Gln), p.(Met555Val); and of uncertain significance, p.(Arg27Pro). Our case series describes novel Glycyl-tRNA synthetase variants and demonstrates the clinical utility of Next Generation Sequencing testing for patients with hereditary neuropathy. Identification of novel variants by Next Generation Sequencing illustrates that there exists a wide spectrum of clinical features and supports the newer simplified classification of neuropathies.
Asunto(s)
Enfermedad de Charcot-Marie-Tooth/genética , Enfermedad de Charcot-Marie-Tooth/fisiopatología , Glicina-ARNt Ligasa/genética , Atrofia Muscular Espinal/genética , Atrofia Muscular Espinal/fisiopatología , Adolescente , Adulto , Niño , Preescolar , Femenino , Secuenciación de Nucleótidos de Alto Rendimiento , Humanos , Lactante , Masculino , Persona de Mediana Edad , Adulto JovenRESUMEN
We describe the presentation and follow-up of a three-year-old girl with nemaline myopathy due to a de-novo variant in ACTA1 (encoding skeletal alpha actin) and moderately low enzyme level of Complex I of the mitochondrial respiratory chain. She presented in the neonatal period with hypotonia, followed by weakness in the facial, bulbar, respiratory and neck flexors muscles. A biopsy of her quadriceps muscle at the age of one year showed nemaline rods. Based on her clinical presentation of a congenital myopathy and histopathological features on a muscle biopsy, ACTA1 was sequenced, and this revealed a novel sequence variant, c.760 A>C p. (Asn254His). In addition, mitochondrial respiratory chain enzymatic activity of skeletal muscle biopsy showed a moderately low activity of complex I (nicotinamide adenine dinucleotide (NADH): ubiquinone oxidoreductase). Disturbances of Complex I of the respiratory chain have been reported in patients with nemaline myopathy, although the mechanism remains unclear.
Asunto(s)
Actinas/genética , Complejo I de Transporte de Electrón/deficiencia , Enfermedades Mitocondriales/genética , Miopatías Nemalínicas/genética , Preescolar , Complejo I de Transporte de Electrón/genética , Femenino , Humanos , Enfermedades Mitocondriales/enzimología , Enfermedades Mitocondriales/patología , Músculo Esquelético/enzimología , Músculo Esquelético/patología , Miopatías Nemalínicas/enzimología , Miopatías Nemalínicas/patologíaRESUMEN
OBJECTIVE: To assess the real-world management practices of subjects with type 2 diabetes mellitus (T2DM) and type 1 diabetes mellitus (T1DM) in India. METHODS: This cross-sectional study was conducted between 7 March 2016 and 15 May 2016 in India as part of the seventh wave (2016) of the International Diabetes Management Practices Study (IDMPS). Adult subjects with T1DM or T2DM visiting physicians during a 2-week recruitment period were included. RESULTS: A total of 55 physicians included 539 subjects who met eligibility criteria. Of 495 subjects with T2DM, 303 were treated with oral glucose lowering drugs (OGLDs) only, 158 were treated with OGLD + insulin, and 27 received insulin only. Among 44 subjects with T1DM receiving insulin, 13 (29.5%) were also treated with OGLD therapy. The most commonly used insulin regimens were basal alone (69/184; 37.5%) and premixed alone (63/184; 34.2%) in subjects with T2DM, and basal + prandial insulin (24/44; 54.5%) in subjects with T1DM. Proportions of subjects achieving glycemic targets were low [glycated haemoglobin (HbA1c) <7%: T1DM = 7.3% (3/44), T2DM = 25.2% (106/495); as targeted by the treating physician: T1DM = 31.8% (14/44), T2DM = 32.1% (59/185); global target: T1DM = 4.8% (2/42) and T2DM = 1.7% (8/482)]. In subjects with T2DM, HbA1c <7% was noted in 11/22 subjects receiving insulin only and 76/260 receiving only OGLDs. Lack of experience in self-managing insulin dosing, poor diabetes education and failure to titrate insulin dosages were the main reasons for non-achievement of glycemic targets. CONCLUSION: Timely insulinization, education and empowerment of people with diabetes may help improve glycemic control in India.
RESUMEN
Inappropriate stimulation or defective negative regulation of the type I interferon response can lead to autoinflammation. In genetically uncharacterized cases of the type I interferonopathy Aicardi-Goutières syndrome, we identified biallelic mutations in LSM11 and RNU7-1, which encode components of the replication-dependent histone pre-mRNA-processing complex. Mutations were associated with the misprocessing of canonical histone transcripts and a disturbance of linker histone stoichiometry. Additionally, we observed an altered distribution of nuclear cyclic guanosine monophosphate-adenosine monophosphate synthase (cGAS) and enhanced interferon signaling mediated by the cGAS-stimulator of interferon genes (STING) pathway in patient-derived fibroblasts. Finally, we established that chromatin without linker histone stimulates cyclic guanosine monophosphate-adenosine monophosphate (cGAMP) production in vitro more efficiently. We conclude that nuclear histones, as key constituents of chromatin, are essential in suppressing the immunogenicity of self-DNA.
Asunto(s)
Cromatina/metabolismo , Histonas/metabolismo , Interferón Tipo I/biosíntesis , Precursores del ARN/metabolismo , Proteínas de Unión al ARN/genética , Ribonucleoproteína Nuclear Pequeña U7/genética , Enfermedades Autoinmunes del Sistema Nervioso/genética , Enfermedades Autoinmunes del Sistema Nervioso/inmunología , Línea Celular , ADN/inmunología , Regulación de la Expresión Génica/genética , Regulación de la Expresión Génica/inmunología , Células HCT116 , Células HEK293 , Enfermedades Autoinflamatorias Hereditarias/genética , Enfermedades Autoinflamatorias Hereditarias/inmunología , Humanos , Proteínas de la Membrana/metabolismo , Malformaciones del Sistema Nervioso/genética , Malformaciones del Sistema Nervioso/inmunología , Nucleótidos Cíclicos/biosíntesis , Nucleotidiltransferasas/metabolismoRESUMEN
Developing an automatic signature verification system is challenging and demands a large number of training samples. This is why synthetic handwriting generation is an emerging topic in document image analysis. Some handwriting synthesizers use the motor equivalence model, the well-established hypothesis from neuroscience, which analyses how a human being accomplishes movement. Specifically, a motor equivalence model divides human actions into two steps: 1) the effector independent step at cognitive level and 2) the effector dependent step at motor level. In fact, recent work reports the successful application to Western scripts of a handwriting synthesizer, based on this theory. This paper aims to adapt this scheme for the generation of synthetic signatures in two Indic scripts, Bengali (Bangla), and Devanagari (Hindi). For this purpose, we use two different online and offline databases for both Bengali and Devanagari signatures. This paper reports an effective synthesizer for static and dynamic signatures written in Devanagari or Bengali scripts. We obtain promising results with artificially generated signatures in terms of appearance and performance when we compare the results with those for real signatures.
RESUMEN
There is very limited evidence about the views of men with Duchenne muscular dystrophy (DMD) and end of life issues including death and dying. Studies have shown the physiological and psychological benefits of talking about and planning for end of life. Despite policy documents and guidance in the UK about end of life planning, there is consensus on the need for improvement. The study reported here is a qualitative one with 15 men with DMD (aged 20-45 years). Participants could not recall any significant conversations with clinicians about end of life and assumed that clinicians were reluctant to discuss the issue. The men in the study wanted to be given proactive cues that they could bring up topics such as death and dying and wanted to have these conversations with clinicians who combined expert knowledge about the condition as well as good listening skills. Topics of interest to participants included likely nature and place of death; practical planning for funerals and wills; and sources of information and support. Emotional or psychological support to think about end of life was not routinely offered and participants found it very difficult to discuss these issues with family members. The study suggests that more could be done to encourage clinicians, men with Duchenne, family members and the wider NMD community to pay attention to end of life planning issues and the associated need for emotional support and high quality interactions between patients and clinicians.
Asunto(s)
Planificación Anticipada de Atención , Distrofia Muscular de Duchenne/psicología , Cuidado Terminal/psicología , Adulto , Femenino , Humanos , Masculino , Persona de Mediana Edad , Investigación Cualitativa , Adulto JovenRESUMEN
BACKGROUND: A high prevalence of hypogonadism in men with Type-2 diabetes mellitus (T2DM) has been reported worldwide. OBJECTIVES: To evaluate the prevalence of hypogonadism in Indian males with T2DM and assess the primary and secondary hypogonadism along with androgen deficiency. MATERIALS AND METHODS: In this cross-sectional study, 900 men with T2DM were evaluated using androgen deficiency in aging male questionnaire. They were screened for demographic characteristics, gonadal hormone levels, lipid profile, and glycosylated hemoglobin. RESULTS: The prevalence of hypogonadism in T2DM patients was found to be 20.7% (186 out of 900). Hypogonadism was of testicular origin (primary) in 48/186 (25.8%) patients, of pituitary or hypothalamic origin (secondary) in 14/186 (7.53%), and remaining 124/186 (66.67%) patients were found to have low testosterone with the inappropriate normal level of luteinizing hormone and Follicle-stimulating hormone. 451/900 (50.1%) patients were only symptomatic but had normal testosterone levels. Further 263 patients out 900 were asymptomatic, of which 51/900 (5.7%) patients had low levels of testosterone and 212/900 (23.5%) patients had normal testosterone level without symptoms. There were no deaths or other serious adverse events except mild pyrexia which was not related to the study. CONCLUSION: Hypogonadism diagnosis, at times, might not be validated with the help of androgen deficiency questionnaire or symptoms only. Given the large number of patients of T2DM in India, the incidence of hypogonadism is more in diabetic patients as compared to the general population. Hence, implementation of screening programs in diabetic patients is necessary to understand and detect individuals with low serum total testosterone at any early stage and to supplement testosterone accordingly.