Migraine without aura is the most common form of migraine, characterized by recurrent disabling headache and associated autonomic symptoms. To identify common genetic variants associated with this ...migraine type, we analyzed genome-wide association data of 2,326 clinic-based German and Dutch individuals with migraine without aura and 4,580 population-matched controls. We selected SNPs from 12 loci with 2 or more SNPs associated with P values of <1 × 10(-5) for replication testing in 2,508 individuals with migraine without aura and 2,652 controls. SNPs at two of these loci showed convincing replication: at 1q22 (in MEF2D; replication P = 4.9 × 10(-4); combined P = 7.06 × 10(-11)) and at 3p24 (near TGFBR2; replication P = 1.0 × 10(-4); combined P = 1.17 × 10(-9)). In addition, SNPs at the PHACTR1 and ASTN2 loci showed suggestive evidence of replication (P = 0.01; combined P = 3.20 × 10(-8) and P = 0.02; combined P = 3.86 × 10(-8), respectively). We also replicated associations at two previously reported migraine loci in or near TRPM8 and LRP1. This study identifies the first susceptibility loci for migraine without aura, thereby expanding our knowledge of this debilitating neurological disorder.
Celotno besedilo
Dostopno za:
DOBA, IJS, IZUM, KILJ, NUK, PILJ, PNG, SAZU, UILJ, UKNU, UL, UM, UPUK
Abstract
Background
Renal angiomyolipoma occurs at a high frequency in patients with tuberous sclerosis complex (TSC) and is associated with potentially life-threatening complications. Despite this ...frequency and severity, there are no large population-based cohort studies. Here we present baseline and follow-up data of the international TuberOus SClerosis registry to increase disease Awareness (TOSCA) with an aim to provide detailed clinical characteristics of renal angiomyolipoma among patients with TSC.
Methods
Patients of any age with a documented clinic visit for TSC within 12 months or who were newly diagnosed with TSC before participation in the registry were eligible. Data specific to renal angiomyolipoma included physical tumour characteristics (multiple, bilateral, lesion size and growing lesions), clinical signs and symptoms, and management. The effects of age, gender and genotype on the prevalence of renal angiomyolipoma were also evaluated.
Results
Renal angiomyolipoma was reported in 51.8% of patients at baseline, with higher frequency in female patients (57.8% versus 42.2%). The median age at diagnosis was 12 years. Prevalence of angiomyolipoma was higher in patients with TSC2 compared with TSC1 mutations (59.2% versus 33.3%, P < 0.01). Of the 1031 patients with angiomyolipoma at baseline, multiple lesions were reported in 88.4% and bilateral in 83.9% of patients, while the size of angiomyolipoma was >3 cm in 34.3% of patients. Most patients were asymptomatic (82%). Frequently reported angiomyolipoma-related symptoms included bleeding, pain, elevated blood pressure and impaired renal function. Embolization and mammalian target of rapamycin inhibitors were the two most common treatment modalities.
Conclusions
The TOSCA registry highlights the burden of renal angiomyolipoma in patients with TSC and shows that renal manifestations are initially asymptomatic and are influenced by gender and genotype. Furthermore, the occurrence of significant problems from angiomyolipoma in a minority of younger patients suggests that surveillance should begin in infancy or at initial diagnosis.
Axon pathfinding and synapse formation are essential processes for nervous system development and function. The assembly of myelinated fibres and nodes of Ranvier is mediated by a number of cell ...adhesion molecules of the immunoglobulin superfamily including neurofascin, encoded by the NFASC gene, and its alternative isoforms Nfasc186 and Nfasc140 (located in the axonal membrane at the node of Ranvier) and Nfasc155 (a glial component of the paranodal axoglial junction). We identified 10 individuals from six unrelated families, exhibiting a neurodevelopmental disorder characterized with a spectrum of central (intellectual disability, developmental delay, motor impairment, speech difficulties) and peripheral (early onset demyelinating neuropathy) neurological involvement, who were found by exome or genome sequencing to carry one frameshift and four different homozygous non-synonymous variants in NFASC. Expression studies using immunostaining-based techniques identified absent expression of the Nfasc155 isoform as a consequence of the frameshift variant and a significant reduction of expression was also observed in association with two non-synonymous variants affecting the fibronectin type III domain. Cell aggregation studies revealed a severely impaired Nfasc155-CNTN1/CASPR1 complex interaction as a result of the identified variants. Immunofluorescence staining of myelinated fibres from two affected individuals showed a severe loss of myelinated fibres and abnormalities in the paranodal junction morphology. Our results establish that recessive variants affecting the Nfasc155 isoform can affect the formation of paranodal axoglial junctions at the nodes of Ranvier. The genetic disease caused by biallelic NFASC variants includes neurodevelopmental impairment and a spectrum of central and peripheral demyelination as part of its core clinical phenotype. Our findings support possible overlapping molecular mechanisms of paranodal damage at peripheral nerves in both the immune-mediated and the genetic disease, but the observation of prominent central neurological involvement in NFASC biallelic variant carriers highlights the importance of this gene in human brain development and function.
Reanalysis of inconclusive exome/genome sequencing data increases the diagnosis yield of patients with rare diseases. However, the cost and efforts required for reanalysis prevent its routine ...implementation in research and clinical environments. The Solve-RD project aims to reveal the molecular causes underlying undiagnosed rare diseases. One of the goals is to implement innovative approaches to reanalyse the exomes and genomes from thousands of well-studied undiagnosed cases. The raw genomic data is submitted to Solve-RD through the RD-Connect Genome-Phenome Analysis Platform (GPAP) together with standardised phenotypic and pedigree data. We have developed a programmatic workflow to reanalyse genome-phenome data. It uses the RD-Connect GPAP's Application Programming Interface (API) and relies on the big-data technologies upon which the system is built. We have applied the workflow to prioritise rare known pathogenic variants from 4411 undiagnosed cases. The queries returned an average of 1.45 variants per case, which first were evaluated in bulk by a panel of disease experts and afterwards specifically by the submitter of each case. A total of 120 index cases (21.2% of prioritised cases, 2.7% of all exome/genome-negative samples) have already been solved, with others being under investigation. The implementation of solutions as the one described here provide the technical framework to enable periodic case-level data re-evaluation in clinical settings, as recommended by the American College of Medical Genetics.
Hemiplegic migraine (HM) is a rare and severe subtype of autosomal dominant migraine, characterized by a complex aura including some degree of motor weakness. Mutations in four genes (CACNA1A, ...ATP1A2, SCN1A and PRRT2) have been detected in familial and in sporadic cases. This genetically and clinically heterogeneous disorder is often accompanied by permanent ataxia, epileptic seizures, mental retardation, and chronic progressive cerebellar atrophy. Here we report a mutation screening in the CACNA1A and ATP1A2 genes in 18 patients with HM. Furthermore, intragenic copy number variant (CNV) analysis was performed in CACNA1A using quantitative approaches. We identified four previously described missense CACNA1A mutations (p.Ser218Leu, p.Thr501Met, p.Arg583Gln, and p.Thr666Met) and two missense changes in the ATP1A2 gene, the previously described p.Ala606Thr and the novel variant p.Glu825Lys. No structural variants were found. This genetic screening allowed the identification of more than 30% of the disease alleles, all present in a heterozygous state. Functional consequences of the CACNA1A‐p.Thr501Met mutation, previously described only in association with episodic ataxia, and ATP1A2‐p.Glu825Lys, were investigated by means of electrophysiological studies, cell viability assays or Western blot analysis. Our data suggest that both these variants are disease‐causing.
Hemiplegic migraine (HM) is a rare and severe subtype of autosomal dominant migraine. Here we report a mutation and CNV screening in the CACNA1A and ATP1A2 genes in 18 HM patients. We identified four previously described missense changes in CACNA1A and two missense changes in ATP1A2, one of them, p.Glu825Lys, novel. No structural variants were found. Functional studies including electrophysiology, cell viability assays, and Western blot analysis, were performed for two of the identified mutations, suggesting pathogenicity.
ABSTRACT
BACKGROUND AND PURPOSE
The diagnosis of Chiari malformation type I (CMI) relies on MRI identification of a tonsillar descent (TD) through the foramen magnum, reflecting the overcrowding of ...an underdeveloped posterior cranial fossa (PCF). However, TD occurs in some patients with normal‐sized PCF and, conversely, some patients with borderline or no TD have small PCF. We thus sought to identify a set of prototypic PCF measures for the diagnosis of CMI.
METHODS
We performed nineteen measurements of the PCF on sagittal MRI of 100 cases with cerebellar TD ≥5 mm and 50 control individuals, compared the average values in both cohorts and used logistic regression to devise a probability model to predict CMI status.
RESULTS
Significant decrements were detected for several PCF‐related measures in the patients’ cohort. We developed a probability model that combined seven of these parameters to predict diagnosis with 93% sensitivity and 92% specificity.
CONCLUSIONS
The addition of simple morphometric measurements in the diagnostic work‐up of patients with suspected CMI may facilitate radiological diagnosis. Moreover, identification of the subset of CMI that arise from basichondrocranium underdevelopment is important for both, selection of the most appropriate therapeutic approach as well as proper CMI categorization in research studies.
Objective
Phosphomannomutase deficiency (PMM2 congenital disorder of glycosylation PMM2‐CDG) causes cerebellar syndrome and strokelike episodes (SLEs). SLEs are also described in patients with ...gain‐of‐function mutations in the CaV2.1 channel, for which acetazolamide therapy is suggested. Impairment in N‐glycosylation of CaV2.1 promotes gain‐of‐function effects and may participate in cerebellar syndrome in PMM2‐CDG. AZATAX was designed to establish whether acetazolamide is safe and improves cerebellar syndrome in PMM2‐CDG.
Methods
A clinical trial included PMM2‐CDG patients, with a 6‐month first‐phase single acetazolamide therapy group, followed by a randomized 5‐week withdrawal phase. Safety was assessed. The primary outcome measure was improvement in the International Cooperative Ataxia Rating Scale (ICARS). Other measures were the Nijmegen Pediatric CDG Rating Scale (NPCRS), a syllable repetition test (PATA test), and cognitive scores.
Results
Twenty‐four patients (mean age = 12.3 ± 4.5 years) were included, showing no serious adverse events. Thirteen patients required dose adjustment due to low bicarbonate or asthenia. There were improvements on ICARS (34.9 ± 23.2 vs 40.7 ± 24.8, effect size = 1.48, 95% confidence interval CI = 4.0–7.6, p < 0.001), detected at 6 weeks in 18 patients among the 20 responders, on NPCRS (95% CI = 0.3–1.6, p = 0.013) and on the PATA test (95% CI = 0.5–3.0, p = 0.006). Acetazolamide improved prothrombin time, factor X, and antithrombin. Clinical severity, epilepsy, and lipodystrophy predicted greater response. The randomized withdrawal phase showed ICARS worsening in the withdrawal group (effect size = 1.46, 95% CI = 2.65–7.52, p = 0.001).
Interpretation
AZATAX is the first clinical trial of PMM2‐CDG. Acetazolamide is well tolerated and effective for motor cerebellar syndrome. Its ability to prevent SLEs and its long‐term effects on kidney function should be addressed in future studies. Ann Neurol 2019;85:740–751
Background
Cortical spreading depolarization, the cause of migraine aura, is a short-lasting depolarization wave that moves across the brain cortex, transiently suppressing neuronal activity. ...Prophylactic treatments for migraine, such as topiramate or valproate, reduce the number of cortical spreading depression events in rodents.
Objective
To investigate whether cortical spreading depolarization with and without chronic treatment with topiramate or valproate affect the DNA methylation of the cortex.
Methods
Sprague-Dawley rats were intraperitoneally injected with saline, topiramate or valproate for four weeks when cortical spreading depolarization were induced and genome-wide DNA methylation was performed in the cortex of six rats per group.
Results
The DNA methylation profile of the cortex was significantly modified after cortical spreading depolarization, with and without topiramate or valproate. Interestingly, topiramate reduced by almost 50% the number of differentially methylated regions, whereas valproate increased them by 17%, when comparing to the non-treated group after cortical spreading depolarization induction. The majority of the differentially methylated regions lay within intragenic regions, and the analyses of functional group over-representation retrieved several enriched functions, including functions related to protein processing in the cortical spreading depolarization without treatment group; functions related to metabolic processes in the cortical spreading depolarization with topiramate group; and functions related to synapse and ErbB, MAPK or retrograde endocannabinoid signaling in the cortical spreading depolarization with valproate group.
Conclusions
Our results may provide insights into the underlying physiological mechanisms of migraine with aura and emphasize the role of epigenetics in migraine susceptibility.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
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