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Lafora disease (LD) is a severe form of progressive myoclonus epilepsy inherited in an autosomal recessive fashion. It is associated with biallelic pathogenic variations in EPM2A or NHLRC1, which encode laforin and malin, respectively. The disease usually starts with adolescent onset seizures followed by progressive dementia, refractory status epilepticus and eventually death within 10 years of onset. LD is generally accepted as having a homogenous clinical course with no considerable differences between EPM2A or NHLRC1 associated forms. Nevertheless, late-onset and slow progressing forms of the disease have also been reported. Herein, we have performed clinical and genetic analyses of 14 LD patients from 12 different families and identified 8 distinct biallelic variations in these patients. Five of these variations were novel and/or associated with the LD phenotype for the first time. Interestingly, almost half of the cases were homozygous for the rare rs769301934 (NM_198586.3(NHLRC1): c.436 G > A; p.(Asp146Asn)) allele in NHLRC1. A less severe phenotype with an onset at a later age may be the reason for the biased inflation of this variant, which is already present in the human gene pool and can hence arise in the homozygous form in populations with increased parental consanguinity.
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Alelos , Estudios de Asociación Genética , Predisposición Genética a la Enfermedad , Variación Genética , Enfermedad de Lafora/diagnóstico , Enfermedad de Lafora/genética , Ubiquitina-Proteína Ligasas/genética , Consanguinidad , Familia , Estudios de Asociación Genética/métodos , Genotipo , Humanos , Linaje , Fenotipo , TurquíaRESUMEN
Mutations in the sarcomeric protein titin, encoded by TTN, are emerging as a common cause of myopathies. The diagnosis of a TTN-related myopathy is, however, often not straightforward due to clinico-pathological overlap with other myopathies and the prevalence of TTN variants in control populations. Here, we present a combined clinico-pathological, genetic and biophysical approach to the diagnosis of TTN-related myopathies and the pathogenicity ascertainment of TTN missense variants. We identified 30 patients with a primary TTN-related congenital myopathy (CM) and two truncating variants, or one truncating and one missense TTN variant, or homozygous for one TTN missense variant. We found that TTN-related myopathies show considerable overlap with other myopathies but are strongly suggested by a combination of certain clinico-pathological features. Presentation was typically at birth with the clinical course characterized by variable progression of weakness, contractures, scoliosis and respiratory symptoms but sparing of extraocular muscles. Cardiac involvement depended on the variant position. Our biophysical analyses demonstrated that missense mutations associated with CMs are strongly destabilizing and exert their effect when expressed on a truncating background or in homozygosity. We hypothesise that destabilizing TTN missense mutations phenocopy truncating variants and are a key pathogenic feature of recessive titinopathies that might be amenable to therapeutic intervention.
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Conectina/genética , Miotonía Congénita/diagnóstico , Miotonía Congénita/genética , Miotonía Congénita/patología , Adolescente , Adulto , Anciano , Niño , Preescolar , Femenino , Humanos , Lactante , Masculino , Persona de Mediana Edad , Mutación Missense , Adulto JovenRESUMEN
Genetic diseases are a major cause of neonatal morbidity and mortality. The clinical differential diagnosis in severely ill neonates, especially in premature infants, is challenging. Next generation sequencing (NGS) diagnostics is a valuable tool, but the turnaround time is often too long to provide a diagnosis in the time needed for clinical guidance in newborn intensive care units (NICU). To minimize turnaround time, we developed an ultra-rapid whole genome sequencing pipeline and tested it in clinical practice. Our pilot case, was a preterm infant presenting with several crises of dehydration, hypoglycaemia and hyponatremia together with nephrocalcinosis and hypertrophic cardiomyopathy. Whole genome sequencing was performed using a paired-end 2x75bp protocol. Sequencing data were exported after 50 sequencing cycles for a first analysis. After run completion, the rapid-sequencing protocol, a second analysis of the 2 x 75 paired-end run was performed. Both analyses comprised read-mapping and SNP-/indel calling on an on-site Edico Genome DRAGEN server, followed by functional annotation and pathogenicity prediction using in-house scripts. After the first analysis within 17 h, the emergency ultra-rapid protocol identified two novel compound heterozygous variants in the insulin receptor gene (INSR), pathogenic variants in which cause Donohue Syndrome. The genetic diagnosis could be confirmed by detection of hyperinsulinism and patient care adjusted. Nonetheless, we decided to pursue RNA studies, proving the functional effect of the novel splice variant and reduced expression levels of INSR in patients skin fibroblasts.
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Antígenos CD/genética , Enfermedades Genéticas Congénitas/diagnóstico , Secuenciación de Nucleótidos de Alto Rendimiento , Hipoglucemia/diagnóstico , Receptor de Insulina/genética , Deshidratación/diagnóstico , Deshidratación/genética , Femenino , Enfermedades Genéticas Congénitas/genética , Enfermedades Genéticas Congénitas/patología , Humanos , Hipoglucemia/patología , Lactante , Mortalidad Infantil , Recién Nacido , Recien Nacido Prematuro , Unidades de Cuidado Intensivo Neonatal , Masculino , Anotación de Secuencia Molecular , Polimorfismo de Nucleótido Simple/genética , Isoformas de Proteínas/genética , Secuenciación Completa del GenomaRESUMEN
Congenital myopathies (CMs) are a heterogeneous group of inherited muscle disorders characterized by muscle weakness at birth, while limb-girdle muscular dystrophies (LGMD) have a later onset and slower disease progression. Thus, detailed clinical phenotyping of genetically defined disease entities are required for the full understanding of genotype-phenotype correlations. A recently defined myopathic genetic disease entity is caused by bi-allelic variants in a gene coding for pyridine nucleotide-disulfide oxidoreductase domain 1 (PYROXD1) with unknown substrates. Here, we present three patients from two consanguineous Turkish families with mild LGMD, facial weakness, normal CK levels, and slow progress. Genomic analyses revealed a homozygous known pathogenic missense variant (c.464A>G, p.Asn155Ser) in family 1 with two affected females. In the affected male of family 2, we found this variant in a compound heterozygous state together with a novel frameshift variant (c.329_332delTCTG, p.Leu112Valfs*8), which is the second frameshift variant known so far in PYROXD1. We have been able to define a large homozygous region in family 1 sharing a common haplotype with family 2 in the critical region. Our data suggest that c.464A>G is a Turkish founder mutation. To gain deeper insights, we performed a systematic review of all published PYROXD1-related myopathy cases. Our analysis showed that the c.464A > G variant was found in 87% (20/23) of the patients and that it may cause either a childhood- or adult-onset phenotype, irrespective of its presence in a homozygous or compound heterozygous state. Interestingly, only four patients had elevated CK levels (up to 1000 U/L), and cardiac involvement was found in few compound heterozygous cases.
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Debilidad Muscular/genética , Enfermedades Musculares/genética , Distrofia Muscular de Cinturas/genética , Oxidorreductasas actuantes sobre Donantes de Grupos Sulfuro/genética , Adolescente , Adulto , Niño , Preescolar , Femenino , Predisposición Genética a la Enfermedad , Haplotipos , Humanos , Lactante , Recién Nacido , Masculino , Debilidad Muscular/patología , Enfermedades Musculares/patología , Distrofia Muscular de Cinturas/patología , Linaje , Fenotipo , Adulto JovenRESUMEN
An amendment to this paper has been published and can be accessed via a link at the top of the paper.
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PURPOSE: Fetal akinesia has multiple clinical subtypes with over 160 gene associations, but the genetic etiology is not yet completely understood. METHODS: In this study, 51 patients from 47 unrelated families were analyzed using next-generation sequencing (NGS) techniques aiming to decipher the genomic landscape of fetal akinesia (FA). RESULTS: We have identified likely pathogenic gene variants in 37 cases and report 41 novel variants. Additionally, we report putative pathogenic variants in eight cases including nine novel variants. Our work identified 14 novel disease-gene associations for fetal akinesia: ADSSL1, ASAH1, ASPM, ATP2B3, EARS2, FBLN1, PRG4, PRICKLE1, ROR2, SETBP1, SCN5A, SCN8A, and ZEB2. Furthermore, a sibling pair harbored a homozygous copy-number variant in TNNT1, an ultrarare congenital myopathy gene that has been linked to arthrogryposis via Gene Ontology analysis. CONCLUSION: Our analysis indicates that genetic defects leading to primary skeletal muscle diseases might have been underdiagnosed, especially pathogenic variants in RYR1. We discuss three novel putative fetal akinesia genes: GCN1, IQSEC3 and RYR3. Of those, IQSEC3, and RYR3 had been proposed as neuromuscular disease-associated genes recently, and our findings endorse them as FA candidate genes. By combining NGS with deep clinical phenotyping, we achieved a 73% success rate of solved cases.
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Enfermedades Fetales/genética , Factores de Intercambio de Guanina Nucleótido/genética , Proteínas de Unión al ARN/genética , Canal Liberador de Calcio Receptor de Rianodina/genética , Transactivadores/genética , Adolescente , Adulto , Artrogriposis/genética , Artrogriposis/patología , Niño , Preescolar , Variaciones en el Número de Copia de ADN/genética , Femenino , Enfermedades Fetales/patología , Predisposición Genética a la Enfermedad , Secuenciación de Nucleótidos de Alto Rendimiento , Humanos , Lactante , Recién Nacido , Masculino , Enfermedades Musculares/genética , Enfermedades Musculares/patología , Adulto JovenRESUMEN
OBJECTIVE: Horizontal gaze palsy with progressive scoliosis (HGPPS) is a rare, autosomal recessive disorder resulting from axonal midline crossing defect due to variants in ROBO3. METHODS: We retrospectively evaluated demographics, clinical phenotype, course of spinal deformities, and neuroimaging findings of six Turkish patients with HGPPS. We performed targeted gene testing by next-generation sequencing. RESULTS: The median age at symptom onset and diagnosis was 1.5 years (0.5-4), and 11 years (2-16), respectively. Oculomotor signs were the most common presenting symptom (n = 4), followed by scoliosis (n = 2). The course of scoliosis was progressive and accompanied by kyphosis, showed intrafamilial variability, and was corrected surgically in three of the patients. Intellectual disability (n = 4), hypergonadotropic hypogonadism (n = 2), hearing loss (n = 2), and tranisent movement disorders (n = 1) were additional features. Targeted gene sequencing revealed five distinct homozygous variants. Of the four novel variants, two of them were located in the acceptor site of the noncoding region of the gene, remaining two were missense and frameshift variants, located in immunoglobulin-like domain-2, and cytoplasmic signaling motif 2, respectively. Structural magnetic resonance imaging (MRI) and diffusion tensor imaging (DTI) showed the absence of decussation of superior cerebellar peduncle and dorsal transverse pontine fibers. INTERPRETATION: Spectrum of HGPPS is further expanded with novel variants in the ROBO3 with clinical and radiological fingerprints. Spinal deformities require close orthopedic screening and individualized approach. Intellectual disability and hearing loss emerge as additional features. Hypogonadism and transient subtle movement disorders require further attention and confirmation from other series.
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Receptores de Superficie Celular , Escoliosis , Humanos , Escoliosis/genética , Escoliosis/diagnóstico por imagen , Masculino , Femenino , Niño , Adolescente , Preescolar , Estudios Retrospectivos , Receptores de Superficie Celular/genética , Oftalmoplejía Externa Progresiva Crónica/genética , Receptores Inmunológicos/genética , Lactante , Fenotipo , Trastornos Congénitos de Denervación Craneal , Proteínas RoundaboutRESUMEN
PURPOSE: We analyzed the surgical results of patients who were treated and followed up for prostate cancer in our clinic to predict the relationship between periprostatic adipose tissue and patients with and without pathologically upstaged disease. MATERIALS AND METHODS: The study included patients who had undergone robot-assisted radical prostatectomy and preoperative multiparametric prostate magnetic resonance imaging between 18 February 2019 and 1 April 2022. The patients were divided into two groups, and the surgical and transrectal ultrasound-guided biopsy pathology results were compared according to tumor grade and distribution in 124 patients who met the selection criteria. We analyzed the relationships between upgrading/upstaging and periprostatic adipose tissue thickness (PPATT) and subcutaneous adipose tissue thickness (SATT) as measured in magnetic resonance imaging. RESULTS: The median PPATT was 4.03 mm, whereas the median SATT was 36.4 mm. Upgrading was detected in 45 patients (36.3%), and upstaging was detected in 42 patients (33.9%). A receiver operating characteristic regression analysis revealed that a PPATT >3 mm was a predictive factor for upstaging after radical prostatectomy (area under curve=0.623, 95% confidence interval [CI] 0.519-0.727, p=0.025). Multivariate logistic regression analyses revealed that prostate specific antigen density ≥0.15 ng/mL/cm3 (odds ratio [OR] 5.054, 95% CI 2.008-12.724, p=0.001), International Society of Urological Pathology grade ≥4 (OR 9.369, 95% CI 2.109-21.626, p=0.003) and higher PPATT (OR 1.358, 95% CI 1.081-1.707, p=0.009) were independent risk factors for upstaging after radical prostatectomy. CONCLUSIONS: We believe that the PPATT may be a predictive indicator for upstaging after robot-assisted laparoscopic radical prostatectomy.
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Laparoscopía , Imágenes de Resonancia Magnética Multiparamétrica , Robótica , Masculino , Humanos , Próstata/diagnóstico por imagen , Prostatectomía , Tejido Adiposo/diagnóstico por imagenRESUMEN
Background: Pediatric patients with undiagnosed conditions, particularly those suspected of having Mendelian genetic disorders, pose a significant challenge in healthcare. This study investigates the diagnostic yield of whole-genome sequencing (WGS) in a pediatric cohort with diverse phenotypes, particularly focusing on the role of clinical expertise in interpreting WGS results. Methods: A retrospective cohort study was conducted at Acibadem University's Maslak Hospital in Istanbul, Turkey, involving pediatric patients (0-18 years) who underwent diagnostic WGS testing. Clinical assessments, family histories, and previous laboratory and imaging studies were analyzed. Variants were classified and interpreted in conjunction with clinical findings. Results: The cohort comprised 172 pediatric patients, aged 0-5 years (62.8%). International patients (28.5%) were from 20 different countries. WGS was used as a first-tier approach in 61.6% of patients. The diagnostic yield of WGS reached 61.0%, enhanced by reclassification of variants of uncertain significance (VUS) through reverse phenotyping by an experienced clinical geneticist. Consanguinity was 18.6% of the overall cohort. Dual diagnoses were carried out for 8.5% of solved patients. Discussion: Our study particularly advocates for the selection of WGS as a first-tier testing approach in infants and children with rare diseases, who were under 5 years of age, thereby potentially shortening the duration of the diagnostic odyssey. The results also emphasize the critical role of a single clinical geneticist's expertise in deep phenotyping and reverse phenotyping, which contributed significantly to the high diagnostic yield.
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Introduction: Rare and ultra-rare genetic conditions significantly contribute to infant morbidity and mortality, often presenting with atypical features and genetic heterogeneity that complicate management. Rapid genome sequencing (RGS) offers a timely and cost-effective approach to diagnosis, aiding in early clinical management and reducing unnecessary interventions. This pilot study represents the inaugural use of next-generation sequencing (NGS) as a diagnostic instrument for critically ill neonatal and pediatric ICU patients in a Turkish hospital setting. Methods: Ten infants were enrolled based on predefined inclusion criteria, and trio RGS was performed. The mean age of the participants was 124â days, with congenital abnormalities being the most common indication for testing. Three patients had consanguineous parents. The mean turnaround time from enrollment to delivery of results was 169â h, with a diagnostic yield of 50%. Results: Three patients received a definitive molecular diagnosis, impacting their clinical management. Two patients benefited from the exclusion of Mendelian conditions, leading to alternative diagnoses. Discussion: This study demonstrates the feasibility and results of RGS in Turkish hospital settings, emphasizing the importance of timely genetic diagnosis in reducing the diagnostic odyssey for families and improving patient care. Further research is needed to evaluate the cost-effectiveness and applicability of RGS in the Turkish healthcare system for children with diseases of uncertain etiology.
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Rare disease patients constitute a significant part of the healthcare system of all countries. However, the information on the experiences during disease processes and daily life of rare disease patients is still limited. So far, there is a small number of studies conducted in Türkiye, and they mainly cover specific issues like education or anxiety. Here we present a comprehensive survey analysis conducted among the patients and their families within the scope of the Istanbul Solution Platform for Undiagnosed and Rare Diseases-ISTisNA project. A total of 498 individuals responded to the survey, and 58% of the participants answered all questions. The majority of the patients were in the age range of 1-10 years (44.7%), and 91% of all the patients had a precise diagnosis. The diagnosis rate in the first 6 months was 69%, and almost 10% of the patients remained undiagnosed. The mothers were the primary caregivers (72%). Nearly 30% of the caregivers had to quit their jobs and 25% of the patients (0-18 years) had to leave school. Accessing physicians with relevant specialization and reaching treatments/medications/supplements were the two main obstacles the participants mentioned, with a frequency of 81% and 73%, respectively. Around 50% of participants noted that they commonly faced difficulties at work/school and in their social lives. The highest expectation or priority was the establishment of rare disease-specific diagnosis and treatment centers, accurate and detailed information on diseases in the Turkish language, and easy access to physicians, treatments, and supportive therapies. To the best of our knowledge, this is the most comprehensive survey conducted on the rare disease community in Türkiye. These results show that regardless of the country, the individuals affected by rare diseases and their families have similar problems and expectations. On the other hand, regional and country-specific issues are still in the line to be solved. These studies can provide a deeper insight into rare diseases and guide the activities of Türkiye's national rare disease action plan.
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Motivación , Enfermedades Raras , Femenino , Humanos , Lactante , Preescolar , Niño , Atención a la Salud , Ansiedad , MadresRESUMEN
The modulatory effect of C-Vx, a novel therapeutic agent, on the immune system of COVID-19 patients was investigated. The functions of T and NK cells of COVID-19 patients with different disease severity were evaluated by flow cytometry in response to C-Vx stimulation. The levels of pro- and anti-inflammatory cytokines were detected by multiplex assay in supernatants after cell culture with C-Vx. Bradykinin, IRF3, and IFN-α levels were also measured by ELISA in the presence or absence of C-Vx stimulation. As a result, increased CD107a expression was observed on NK cells in response to C-Vx addition. The proliferation of T cell subsets was increased by C-Vx, decreasing by disease severity. IL-4 and IL-10 levels were elevated while IFN-γ and IL-17 levels were reduced in T cells following C-Vx stimulation. However, the levels of pro-inflammatory IL-1ß, IL-6, IL-8, IFN-γ and GM-CSF were significantly increased upon C-Vx stimulation. IFN-α levels tended to increase after incubation with C-Vx. These findings support an immunomodulatory action of C-Vx on the immune system of patients with a mild and moderate phase of COVID-19.
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COVID-19 , Humanos , Citocinas , Interferón gamma/metabolismo , Linfocitos T , Células Asesinas NaturalesRESUMEN
Erroneous immune responses in COVID-19 could have detrimental effects, which makes investigation of immune network underlying COVID-19 pathogenesis a requisite. This study aimed to investigate COVID-19 related alterations within the frame of innate and adaptive immunity. Thirty-four patients clinically diagnosed with mild, moderate and severe COVID-19 disease were enrolled in this study. Decreased ILC1 and increased ILC2 subsets were detected in mild and moderate patients compared to healthy controls. NK cell subsets and cytotoxic capacity of NK cells were decreased in severe patients. Moreover, CD3+ T cells were reduced in severe patients and a negative correlation was found between CD3+ T cells and D-dimer levels. Likewise, moderate and severe patients showed diminished CD3+CD8+ T cells. Unlike T and NK cells, plasmablast and plasma cells were elevated in patients and IgG and IgA levels were particularly increased in severe patients. Severe patients also showed elevated serum levels of pro-inflammatory cytokines such as TNF-α, IL-6 and IL-8, reduced intracellular IFN-γ and increased intracellular IL-10 levels. Our findings emphasize that SARS-CoV-2 infection significantly alters immune responses and innate and acquired immunity are differentially modulated in line with the clinical severity of the disease. Elevation of IL-10 levels in NK cells and reduction of CD3+ and CD8+ T cells in severe patients might be considered as a protective response against the harmful effect of cytokine storm seen in COVID-19.
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COVID-19 , Linfocitos T CD8-positivos/metabolismo , Citocinas/metabolismo , Humanos , Inmunidad Innata , Inmunoglobulina A/metabolismo , Inmunoglobulina G/metabolismo , Interleucina-10/metabolismo , Interleucina-6/metabolismo , Interleucina-8/metabolismo , Células Asesinas Naturales , SARS-CoV-2 , Factor de Necrosis Tumoral alfa/metabolismoRESUMEN
The Coronavirus Disease 2019 (COVID-19) was declared a pandemic in March 2020 by the World Health Organization (WHO). As of May 25th, 2021 there were 2.059.941 SARS-COV2 genome sequences that have been submitted to the GISAID database, with numerous variations. Here, we aim to analyze the SARS-CoV-2 genome data submitted to the GISAID database from Turkey and to determine the variant and clade distributions by the end of May 2021, in accordance with their appearance timeline. We compared these findings to USA, Europe, and Asia data as well. We have also evaluated the effects of spike protein variations, detected in a group of genome sequences of 13 patients who applied to our clinic, by using 3D modeling algorithms. For this purpose, we analyzed 4607 SARS-CoV-2 genome sequences submitted by different lab centers from Turkey to the GISAID database between March 2020 and May 2021. Described mutations were also introduced in silico to the spike protein structure to analyze their isolated impacts on the protein structure. The most abundant clade was GR followed by G, GH, and GRY and we did not detect any V clade. The most common variant was B.1, followed by B.1.1, and the UK variant, B.1.1.7. Our results clearly show a concordance between the variant distributions, the number of cases, and the timelines of different variant accumulations in Turkey. The 3D simulations indicate an increase in the surface hydrophilicity of the reference spike protein and the detected mutations. There was less surface hydrophilicity increase in the Asp614Gly mutation, which exhibits a more compact conformation around the ACE-2 receptor binding domain region, rendering the structure in a "down" conformation. Our genomic findings can help to model vaccination programs and protein modeling may lead to different approaches for COVID-19 treatment strategies.
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Genoma Viral , SARS-CoV-2/genética , Glicoproteína de la Espiga del Coronavirus/química , Adulto , Anciano , Algoritmos , COVID-19/patología , COVID-19/virología , Femenino , Humanos , Masculino , Persona de Mediana Edad , Simulación de Dinámica Molecular , Mutación , Filogenia , Dominios Proteicos/genética , SARS-CoV-2/clasificación , SARS-CoV-2/aislamiento & purificación , SARS-CoV-2/metabolismo , Glicoproteína de la Espiga del Coronavirus/genética , Glicoproteína de la Espiga del Coronavirus/metabolismo , Turquía , Adulto JovenRESUMEN
The interplay between the immune system, sleep dysfunction and cognitive impairment participates in the progression of disability in multiple sclerosis (MS). Our aim was to identify molecular pathways and B cell associated with separate components of MS disability. Benign MS, non-benign MS patients and healthy controls were recruited. Patients underwent polysomnography and cognitive studies. Microarray and bioinformatics analysis performed using peripheral blood mononuclear cell samples identified B cell-associated genes with the most significantly altered expression. Expression levels of these genes were validated by real-time PCR and peripheral blood cell subsets were examined by flow cytometry. Putative correlations among clinical and laboratory parameters were investigated by correlation network analysis. Sleep and cognitive functions were equally impaired in BMS and NBMS. BMS patients showed significantly reduced memory B cell and increased regulatory B cell percentages than NBMS patients. Among genes that were selected by bioinformatics, levels of BLK, BLNK, BANK1, FCRL2, TGFB1 and KCNS3 genes were significantly different among study subgroups. Correlation network analysis showed associations among physical-cognitive disability and sleep dysfunction measures of MS versus expression levels of selected genes. BMS and NBMS differ by physical disability but not cognitive and sleep dysfunction. Different components of disability in MS are associated with peripheral blood B cell ratios and B cell related gene expression levels. Thus, it is likely that altered B cell functions participate in the progression of disability in MS.
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Linfocitos B Reguladores , Disfunción Cognitiva , Esclerosis Múltiple , Trastornos del Sueño-Vigilia , Cognición , HumanosRESUMEN
Genetic generalized epilepsies (GGE) are genetically determined, as their name implies and they are clinically characterized by generalized seizures involving both sides of the brain in the absence of detectable brain lesions or other known causes. GGEs are yet complex and are influenced by many different genetic and environmental factors. Methylation specific epigenetic marks are one of the players of the complex epileptogenesis scenario leading to GGE. In this study, we have set out to perform genome-wide methylation profiling to analyze GGE trios each consisting of an affected parent-offspring couple along with an unaffected parent. We have developed a novel scoring scheme within trios to categorize each locus analyzed as hypo or hypermethylated. This stringent approach classified differentially methylated genes in each trio and helped us to produce trio specific and pooled gene lists with inherited and aberrant methylation levels. In order to analyze the methylation differences from a boarder perspective, we performed enrichment analysis with these lists using the PANOGA software. This collective effort has led us to detect pathways associated with the GGE phenotype, including the neurotrophin signaling pathway. We have demonstrated a trio based approach to genome-wide DNA methylation analysis that identified individual and possibly minor changes in methylation marks that could be involved in epileptogenesis leading to GGE.
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Metilación de ADN , Epigénesis Genética , Epilepsia Generalizada/genética , Predisposición Genética a la Enfermedad , Genoma Humano , Factores de Crecimiento Nervioso/genética , Adulto , Niño , Electroencefalografía , Epilepsia Generalizada/diagnóstico por imagen , Epilepsia Generalizada/metabolismo , Epilepsia Generalizada/fisiopatología , Femenino , Perfilación de la Expresión Génica , Sitios Genéticos , Estudio de Asociación del Genoma Completo , Genotipo , Humanos , Patrón de Herencia , Masculino , Redes y Vías Metabólicas/genética , Factores de Crecimiento Nervioso/metabolismo , Núcleo Familiar , FenotipoRESUMEN
Charcot-Marie-Tooth type 4 (CMT4) is an autosomal recessive severe form of neuropathy with genetic heterogeneity. CMT4B1 is caused by mutations in the myotubularin-related 2 (MTMR2) gene and as a member of the myotubularin family, the MTMR2 protein is crucial for the modulation of membrane trafficking. To enable future clinical trials, we performed a detailed review of the published cases with MTMR2 mutations and describe four novel cases identified through whole-exome sequencing (WES). The four unrelated families harbor novel homozygous mutations in MTMR2 (NM_016156, Family 1: c.1490dupC; p.Phe498IlefsTer2; Family 2: c.1479+1G>A; Family 3: c.1090C>T; p.Arg364Ter; Family 4: c.883C>T; p.Arg295Ter) and present with CMT4B1-related severe early-onset motor and sensory neuropathy, generalized muscle atrophy, facial and bulbar weakness, and pes cavus deformity. The clinical description of the new mutations reported here overlap with previously reported CMT4B1 phenotypes caused by mutations in the phosphatase domain of MTMR2, suggesting that nonsense MTMR2 mutations, which are predicted to result in loss or disruption of the phosphatase domain, are associated with a severe phenotype and loss of independent ambulation by the early twenties. Whereas the few reported missense mutations and also those truncating mutations occurring at the C-terminus after the phosphatase domain cause a rather mild phenotype and patients were still ambulatory above the age 30 years. Charcot-Marie-Tooth neuropathy and Centronuclear Myopathy causing mutations have been shown to occur in proteins involved in membrane remodeling and trafficking pathway mediated by phosphoinositides. Earlier studies have showing the rescue of MTM1 myopathy by MTMR2 overexpression, emphasize the importance of maintaining the phosphoinositides equilibrium and highlight a potential compensatory mechanism amongst members of this pathway. This proved that the regulation of expression of these proteins involved in the membrane remodeling pathway may compensate each other's loss- or gain-of-function mutations by restoring the phosphoinositides equilibrium. This provides a potential therapeutic strategy for neuromuscular diseases resulting from mutations in the membrane remodeling pathway.
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In addition to a complex inheritance pattern in genetic generalized epilepsy (GGE) syndromes, some studies have recently identified SLC2A1 variants which lead to glucose transporter type 1 (GLUT1) defects, in patients diagnosed with GGE. Here, we investigated the possible role of SLC2A1 variants in GGE patients with eyelid myoclonia (EM) which is a rare generalized seizure type associated with drug resistance and cognitive dysfunction. After polymerase chain reaction with designed primers, sequencing of all SLC2A1 exons was performed for 25 GGE-EM patients, as well as a control group of 15 GGE patients with absence seizures. Although various single nucleotide polymorphisms clustered in the ninth exon were detected, no variant was found in the two groups with GGE. Even though the patient number in this study is small, the data suggest that SLC2A1 variants do not play any causative role in GGE associated with EM.
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Epilepsia Generalizada/genética , Transportador de Glucosa de Tipo 1/genética , Mioclonía/genética , Adolescente , Adulto , Epilepsia Generalizada/complicaciones , Femenino , Humanos , Masculino , Persona de Mediana Edad , Mioclonía/etiología , Adulto JovenRESUMEN
Autosomal dominant lateral temporal lobe epilepsy (ADLTE) is an autosomal dominant epileptic syndrome characterized by focal seizures with auditory or aphasic symptoms. The same phenotype is also observed in a sporadic form of lateral temporal lobe epilepsy (LTLE), namely idiopathic partial epilepsy with auditory features (IPEAF). Heterozygous mutations in LGI1 account for up to 50% of ADLTE families and only rarely observed in IPEAF cases. In this study, we analysed a cohort of 26 individuals with LTLE diagnosed according to the following criteria: focal epilepsy with auditory aura and absence of cerebral lesions on brain MRI. All patients underwent clinical, neuroradiological and electroencephalography examinations and afterwards they were screened for mutations in LGI1 gene. The single LGI1 mutation identified in this study is a novel missense variant (NM_005097.2: c.1013T>C; p.Phe338Ser) observed de novo in a sporadic patient. This is the first study involving clinical analysis of a LTLE cohort from Turkey and genetic contribution of LGI1 to ADLTE phenotype. Identification of rare LGI1 gene mutations in sporadic cases supports diagnosis as ADTLE and draws attention to potential familial clustering of ADTLE in suggestive generations, which is especially important for genetic counselling.
Asunto(s)
Epilepsia del Lóbulo Temporal/genética , Mutación , Proteínas/genética , Adulto , Secuencia de Aminoácidos , Estudios de Cohortes , Análisis Mutacional de ADN , Epilepsia del Lóbulo Temporal/diagnóstico , Epilepsia del Lóbulo Temporal/fisiopatología , Femenino , Pruebas Genéticas , Humanos , Péptidos y Proteínas de Señalización Intracelular , Masculino , Datos de Secuencia Molecular , Homología de Secuencia de Aminoácido , TurquíaRESUMEN
Parkinson's disease (PD) is a neurodegenerative disorder characterized by progressive degeneration of the dopaminergic neurons in substantia nigra, presumably due to increased apoptosis and oxidative stress. To investigate whether PD-induced survival/apoptosis gene expression changes can serve as prognostic biomarkers of PD, we measured expression levels of phosphatidylinositol-4,5-bisphosphate 3-kinase (PI3K)/Akt pathway factors and additional apoptotic and anti-apoptotic factors in peripheral blood mononuclear cells (PBMC) of PD patients (n=50) and healthy controls (n=50) by real time PCR. Expression levels of apoptotic factors phosphatase and tensin homolog (PTEN) and mitochondrial apoptosis-inducing factor 1 (AIFM1) were significantly decreased, anti-apoptotic factors DJ-1 and Akt-1 were significantly increased and anti-apoptotic Bcl-2 was significantly decreased in PD patients. Expression levels of AIFM1 were significantly correlated with Hoehn-Yahr scores. Moreover, PD patients with postural instability showed significantly reduced expression levels of anti-apoptotic DJ-1, Akt-1 and mTOR than PD patients without postural instability. Expression profiles of brain samples of mice with rotenone-induced PD model and PBMC samples of PD patients showed remarkable resemblance. Our results indicate that the anti-apoptotic PI3K/Akt pathway is over activated in PD, presumably as an effort to compensate for increased neuronal apoptosis and oxidative stress. By contrast, patients with postural instability show reduced anti-apoptotic factor expression suggesting that this compensating mechanism fails in patients with this particular motor symptom. PBMC expression levels of AIFM1 might serve as a biomarker of disability and disease progression in PD.