272 research outputs found
Blood RNA analysis can increase clinical diagnostic rate and resolve variants of uncertain significance
Purpose
Diagnosis of genetic disorders is hampered by large numbers of variants of uncertain significance (VUSs) identified through next-generation sequencing. Many such variants may disrupt normal RNA splicing. We examined effects on splicing of a large cohort of clinically identified variants and compared performance of bioinformatic splicing prediction tools commonly used in diagnostic laboratories.
Methods
Two hundred fifty-seven variants (coding and noncoding) were referred for analysis across three laboratories. Blood RNA samples underwent targeted reverse transcription polymerase chain reaction (RT-PCR) analysis with Sanger sequencing of PCR products and agarose gel electrophoresis. Seventeen samples also underwent transcriptome-wide RNA sequencing with targeted splicing analysis based on Sashimi plot visualization. Bioinformatic splicing predictions were obtained using Alamut, HSF 3.1, and SpliceAI software.
Results
Eighty-five variants (33%) were associated with abnormal splicing. The most frequent abnormality was upstream exon skipping (39/85 variants), which was most often associated with splice donor region variants. SpliceAI had greatest accuracy in predicting splicing abnormalities (0.91) and outperformed other tools in sensitivity and specificity.
Conclusion
Splicing analysis of blood RNA identifies diagnostically important splicing abnormalities and clarifies functional effects of a significant proportion of VUSs. Bioinformatic predictions are improving but still make significant errors. RNA analysis should therefore be routinely considered in genetic disease diagnostics
Child with Deletion 9p Syndrome Presenting with Craniofacial Dysmorphism, Developmental Delay, and Multiple Congenital Malformations
A 4-month-old Sri Lankan male child case with a de novo terminal deletion in the p22 â pter region of chromosome 9 is described. The child presented with craniofacial dysmorphism, developmental delay, and congenital malformations in agreement with the consensus phenotype. A distinctive feature observed in this child was complete collapse of the left lung due to malformation of lung tissue. Cytogenetic studies confirmed terminal deletion of the short arm of chromosome 9 distal to band p22 [46,XY,del(9)(p22 â pter)]. This is the first reported case of a de novo deletion 9p syndrome associated with pulmonary hypoplasia. This finding contributes to the widening of the spectrum of phenotypic features associated with deletion 9p syndrome
Facile synthesis and proposed mechanism of α,Ïâoxetanyl-telechelic poly(3-nitratomethyl-3-methyl oxetane) by an SN2(i) nitrato displacement method in basic media
The synthesis of a novel heterocyclicâtelechelic polymer, α,Ï-oxetanyl-telechelic poly(3-nitratomethyl-3-methyl oxetane), is described. Infrared spectroscopy (IR), gel permeation chromatography (GPC), and nuclear magnetic resonance (NMR) spectroscopy have been used to confirm the successful synthesis, demonstrating the presence of the telechelic-oxetanyl moieties. Synthesis of the terminal functionalities has been achieved via displacement of nitrato groups, in a manner similar to that employed with other leaving groups such as azido, bromo, and nitro, initiated by nucleophiles. In the present case, displacement occurs on the ends of a nitrato-functionalized polymer driven by the formation of sodium nitrate, which is supported by the polar aprotic solvent N,N-dimethyl formamide. The formation of an alkoxide at the polymer chain ends is favored and allows internal back-biting to the nearest carbon bearing the nitrato group, intrinsically in an SN2(i) reaction, leading to α,Ï-oxetanyl functionalization. The telechelic-oxetanyl moieties have the potential to be cross-linked by chemical (e.g., acidic) or radiative (e.g., ultraviolet) curing methods without the use of high temperatures, usually below 100°C. This type of material was designed for future use as a contraband simulant, whereby it would form the predominant constituent of elastomeric composites comprising rubbery polymer with small quantities of solids, typically crystals of contraband substances, such as explosives or narcotics. This method also provides an alternative approach to ring closure and synthesis of heterocycles
Policing unacceptable protest in England and Wales: A case study of the policing of anti-fracking protests
In recent years public order policing policy in England and Wales has undergone significant changes. A âhuman rights compliantâ model of protest policing has been developed since 2009 and this article makes a contribution to the body of academic work considering the impact of these changes on operational policing. Drawing upon a longitudinal case study of the policing of protests against âfrackingâ in Salford, Greater Manchester, in 2013-2014, the article contrasts post-2009 policy and academic discourses on protest policing with the experiences of anti-fracking protesters. To develop this assessment, the article also draws attention to previously unexplored definitions of acceptable and unacceptable protest set out by police in more recent policy, and considers the extent to which these definitions are reflected in the police response to anti-fracking protest. The article suggests that a police commitment to a human rights approach to protest facilitation is, at least in the case of anti-fracking protest, contingent on the focus and form of political activism
Analysing the European Union's responses to organized crime through different securitization lenses
In the past 30 years, organized crime (OC) has shifted from being an issue of little, or no concern, to being considered one of the key security threats facing the European Union (EU), the economic and political fabric of its society and its citizens. The purpose of this article is to understand how OC has come to be understood as one of the major security threats in the EU, by applying different lenses of Securitization Theory (ST). More specifically, the research question guiding this article is whether applying different ST approaches can lead us to draw differing conclusions as to whether OC has been successfully securitized in the EU. Building on the recent literature that argues that this theoretical framework has branched out into different approaches, this article wishes to contrast two alternative views of how a security problem comes into being, in order to verify whether different approaches can lead to diverging conclusions regarding the same phenomenon. The purpose of this exercise is to contribute to the further development of ST by pointing out that the choice in approach bears direct consequences on reaching a conclusion regarding the successful character of a securitization process. Starting from a reflection on ST, the article proceeds with applying a âlinguistic approachâ to the case study, which it then contrasts with a âsociological approachâ. The article proposes that although the application of a âlinguistic approachâ seems to indicate that OC has become securitized in the EU, it also overlooks a number of elements, which the âsociological approachâ renders visible and which lead us to refute the initial conclusion
The impact of curriculum hierarchies on the development of professional self in teaching: student-teachers of drama negotiating issues of subject status at the interface between drama and English
At the level of policy the relative âvalueâ of subjects is determined by their official curriculum designation, creating a hierarchy of learning within which particular subjects are categorised as optional to the educational experience of young people. This situation is well-illustrated by the marginalised position of drama in the National Curriculum for England and Wales in which drama appears as an adjunct to the âcoreâ subject English. Yet at school level drama has survived as a discrete and reasonably embedded subject. Drawing on questionnaire and interview data, I investigate the effects of this mismatch on the emergence of pedagogical content knowledge, linked to notions of professional self, in drama student-teachers at one university in the UK. Findings indicate that the student-teachers, whilst not entirely eschewing a less-regulated relationship between the two subjects, view the curriculum for English and its accompanying assessment regime as an inadequate host for drama. In addition, they regard teacher autonomy over curriculum content and pedagogy as indicative of a high degree of professional expertise. This suggests that a case can be made for re-evaluating the nature of the relationship between drama and English and its representation in policy-constructed curricula
A systematic analysis of splicing variants identifies new diagnoses in the 100,000 Genomes Project
Background
Genomic variants which disrupt splicing are a major cause of rare genetic diseases. However, variants which lie outside of the canonical splice sites are difficult to interpret clinically. Improving the clinical interpretation of non-canonical splicing variants offers a major opportunity to uplift diagnostic yields from whole genome sequencing data.
Methods
Here, we examine the landscape of splicing variants in whole-genome sequencing data from 38,688 individuals in the 100,000 Genomes Project and assess the contribution of non-canonical splicing variants to rare genetic diseases. We use a variant-level constraint metric (the mutability-adjusted proportion of singletons) to identify constrained functional variant classes near exonâintron junctions and at putative splicing branchpoints. To identify new diagnoses for individuals with unsolved rare diseases in the 100,000 Genomes Project, we identified individuals with de novo single-nucleotide variants near exonâintron boundaries and at putative splicing branchpoints in known disease genes. We identified candidate diagnostic variants through manual phenotype matching and confirmed new molecular diagnoses through clinical variant interpretation and functional RNA studies.
Results
We show that near-splice positions and splicing branchpoints are highly constrained by purifying selection and harbour potentially damaging non-coding variants which are amenable to systematic analysis in sequencing data. From 258 de novo splicing variants in known rare disease genes, we identify 35 new likely diagnoses in probands with an unsolved rare disease. To date, we have confirmed a new diagnosis for six individuals, including four in whom RNA studies were performed.
Conclusions
Overall, we demonstrate the clinical value of examining non-canonical splicing variants in individuals with unsolved rare diseases
Cortical injury in multiple sclerosis; the role of the immune system
The easily identifiable, ubiquitous demyelination and neuronal damage that occurs within the cerebral white matter of patients with multiple sclerosis (MS) has been the subject of extensive study. Accordingly, MS has historically been described as a disease of the white matter. Recently, the cerebral cortex (gray matter) of patients with MS has been recognized as an additional and major site of disease pathogenesis. This acknowledgement of cortical tissue damage is due, in part, to more powerful MRI that allows detection of such injury and to focused neuropathology-based investigations. Cortical tissue damage has been associated with inflammation that is less pronounced to that which is associated with damage in the white matter. There is, however, emerging evidence that suggests cortical damage can be closely associated with robust inflammation not only in the parenchyma, but also in the neighboring meninges. This manuscript will highlight the current knowledge of inflammation associated with cortical tissue injury. Historical literature along with contemporary work that focuses on both the absence and presence of inflammation in the cerebral cortex and in the cerebral meninges will be reviewed
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