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Down's syndrome (trisomy 21) is well recognized to be associated with several autoimmune conditions such as hypothyroidism, celiac disease, and diabetes mellitus. Antiphospholipid syndrome (APS), an immune disorder, can cause a stroke due to the prothrombotic state. APS is associated with several autoimmune diseases including systemic lupus erythematosus, rheumatoid arthritis, and systemic vasculitis, as well as Down's syndrome. Down's syndrome is linked to several other risk factors for stroke including congenital heart disease, moyamoya disease, and arterial dissection. We present the case of a 3-year-old girl child patient with Down's syndrome, who presented with an acute arterial ischemic stroke secondary to carotid artery dissection and subsequently was also confirmed to have APS. We review the literature on Down's syndrome and APS, the proposed pathophysiology, and management strategies. We present a case of a 3-year-old girl with Down's syndrome and who presented with stroke, review previously published cases, and discuss the conditions and their management. Autoimmune conditions, such as antiphospholipid syndrome, are more common in individuals with Down's syndrome, and as such should be investigated when these children present with symptoms suggestive of stroke.

BACKGROUND: The U.K. 100,000 Genomes Project is in the process of investigating the role of genome sequencing in patients with undiagnosed rare diseases after usual care and the alignment of this research with health care implementation in the U.K. National Health Service. Other parts of this project focus on patients with cancer and infection.METHODS: We conducted a pilot study involving 4660 participants from 2183 families, among whom 161 disorders covering a broad spectrum of rare diseases were present. We collected data on clinical features with the use of Human Phenotype Ontology terms, undertook genome sequencing, applied automated variant prioritization on the basis of applied virtual gene panels and phenotypes, and identified novel pathogenic variants through research analysis.RESULTS: Diagnostic yields varied among family structures and were highest in family trios (both parents and a proband) and families with larger pedigrees. Diagnostic yields were much higher for disorders likely to have a monogenic cause (35%) than for disorders likely to have a complex cause (11%). Diagnostic yields for intellectual disability, hearing disorders, and vision disorders ranged from 40 to 55%. We made genetic diagnoses in 25% of the probands. A total of 14% of the diagnoses were made by means of the combination of research and automated approaches, which was critical for cases in which we found etiologic noncoding, structural, and mitochondrial genome variants and coding variants poorly covered by exome sequencing. Cohortwide burden testing across 57,000 genomes enabled the discovery of three new disease genes and 19 new associations. Of the genetic diagnoses that we made, 25% had immediate ramifications for clinical decision making for the patients or their relatives.CONCLUSIONS: Our pilot study of genome sequencing in a national health care system showed an increase in diagnostic yield across a range of rare diseases. (Funded by the National Institute for Health Research and others.).

Objectives The aim of this study was to describe the clinicopathological findings, management and outcome of cats with refeeding syndrome (RS) following prolonged starvation. Methods Records from four referral hospitals were searched between May 2013 and November 2019 and retrospectively evaluated. Inclusion criteria were the presence of a risk factor for RS, such as severe weight loss or emaciation following a period of presumed starvation, hypophosphataemia or a delta phosphorous exceeding 30% reduction following refeeding, being treated on the basis of a clinical diagnosis of RS and one or more derangement of hypokalaemia, hypoglycaemia or hyperglycaemia. Results Eleven cats were identified, which had been missing for a median of 6 weeks (range 3–104 weeks). Mean ± SD percentage weight loss was 46% ± 7% (n = 8). Eight of 11 cats developed hypophosphataemia with a mean delta phosphorous of −47% ± 9%. All cats were documented to be hypokalaemic. During hospitalisation, 10/11 cats developed hyperglycaemia and 7/11 cats developed hypoglycaemia. Cardiovascular, gastrointestinal and neurological signs were common. Eight of 11 cats displayed new or progressive neurological deficits after refeeding, including mentation changes and cerebellar dysfunction. All cats became anaemic and seven cats required a blood transfusion. Eight cats survived to discharge after a mean of 14 ± 4 days of hospitalisation. Six cats developed acute kidney injury (AKI; International Renal Interest Society stage 1). The presence of AKI ( P = 0.024) was associated with non-survival and maximum bilirubin concentration was significantly higher in non-survivors ( P = 0.018). Conclusions and relevance Cats with RS in this cohort had been missing, presumed starved, for more than 3 weeks. In addition to hypophosphataemia and hypokalaemia, altered glucose homeostasis and organ damage involving the liver and kidneys were common. Cats with RS appear to have a good prognosis, but prolonged intensive care is required.

PURPOSE: A key property to consider in all genetic tests is clinical utility, the ability of the test to influence patient management and health outcomes. Here we assess the current clinical utility of genetic testing in diverse pediatric inherited eye disorders (IEDs).METHODS: Two hundred one unrelated children (0-5 years old) with IEDs were ascertained through the database of the North West Genomic Laboratory Hub, Manchester, UK. The cohort was collected over a 7-year period (2011-2018) and included 74 children with bilateral cataracts, 8 with bilateral ectopia lentis, 28 with bilateral anterior segment dysgenesis, 32 with albinism, and 59 with inherited retinal disorders. All participants underwent panel-based genetic testing.RESULTS: The diagnostic yield of genetic testing for the cohort was 64% (ranging from 39% to 91% depending on the condition). The test result led to altered management (including preventing additional investigations or resulting in the introduction of personalized surveillance measures) in 33% of probands (75% for ectopia lentis, 50% for cataracts, 33% for inherited retinal disorders, 7% for anterior segment dysgenesis, 3% for albinism).CONCLUSION: Genetic testing helped identify an etiological diagnosis in the majority of preschool children with IEDs. This prevented additional unnecessary testing and provided the opportunity for anticipatory guidance in significant subsets of patients.

International audience; In this paper, we consider the graph alignment problem, which is the problem of recovering, given two graphs, a one-to-one mapping between nodes that maximizes edge overlap. This problem can be viewed as a noisy version of the well-known graph isomorphism problem and appears in many applications, including social network deanonymization and cellular biology. Our focus here is on partial recovery, i.e., we look for a one-to-one mapping which is correct on a fraction of the nodes of the graph rather than on all of them, and we assume that the two input graphs to the problem are correlated Erdős-Rényi graphs of parameters (n, q, s). Our main contribution is then to give necessary and sufficient conditions on (n, q, s) under which partial recovery is possible with high probability as the number of nodes n goes to infinity. In particular, we show that it is possible to achieve partial recovery in the nqs = Θ(1) regime under certain additional assumptions.

Purpose To characterize the molecular mechanism underpinning early-onset macular drusen (EOMD), a phenotypically severe subtype of age-related macular degeneration (AMD), in a subgroup of patients. Design Multicenter case series, in vitro experimentation, and retrospective analysis of previously reported variants. Participants Seven families with apparently autosomal dominant EOMD. Methods Patients underwent a comprehensive ophthalmic assessment. Affected individuals from families A, B, and E underwent whole exome sequencing. The probands from families C, D, F, and G underwent Sanger sequencing analysis of the complement factor H (CFH) gene. Mutant recombinant factor H like-1 (FHL-1) proteins were expressed in HEK293 cells to assess the impact on FHL-1 expression and function. Previously reported EOMD-causing variants in CFH were reviewed. Main Outcome Measures Detailed clinical phenotypes, genomic findings, in vitro characterization of mutation effect on protein function, and postulation of the pathomechanism underpinning EOMD. Results All affected participants demonstrated bilateral drusen. The earliest reported age of onset was 16 years (median, 46 years). Ultra-rare (minor allele frequency [MAF], ≤0.0001) CFH variants were identified as the cause of disease in each family: CFH c.1243del, p.(Ala415ProfsTer39) het; c.350+1G→T het; c.619+1G→A het, c.380G→A, p.(Arg127His) het; c.694C→T p.(Arg232Ter) het (identified in 2 unrelated families in this cohort); and c.1291T→A, p.(Cys431Ser). All mutations affect complement control protein domains 2 through 7, and thus are predicted to impact both FHL-1, the predominant isoform in Bruch’s membrane (BrM) of the macula, and factor H (FH). In vitro analysis of recombinant proteins FHL-1R127H, FHL-1A415f/s, and FHL-1C431S demonstrated that they are not secreted, and thus are loss-of-function proteins. Review of 29 previously reported EOMD-causing mutations found that 75.8% (22/29) impact FHL-1 and FH. In total, 86.2% (25/29) of EOMD-associated variants cause haploinsufficiency of FH or FHL-1. Conclusions Early-onset macular drusen is an underrecognized, phenotypically severe subtype of AMD. We propose that haploinsufficiency of FHL-1, the main regulator of the complement pathway in BrM, where drusen develop, is an important mechanism underpinning the development of EOMD in a number of cases. Understanding the molecular basis of EOMD will shed light on AMD pathogenesis given their pathologic similarities.

Background Inherited vitreoretinopathies arise as a consequence of congenital retinal vascularisation abnormalities. They represent a phenotypically and genetically heterogeneous group of disorders that can have a major impact on vision. Several genes encoding proteins and effectors of the canonical Wnt/β-catenin pathway have been associated and precise diagnosis, although difficult, is essential for proper clinical management including syndrome specific management where appropriate. This work aimed to investigate the molecular basis of disease in a single proband born to consanguineous parents, who presented with microphthalmia, persistent foetal vasculature, posterior lens vacuoles, vitreoretinal dysplasia, microcephaly, hypotelorism and global developmental delay, and was registered severely visually impaired by 5 months of age. Methods Extensive genomic pre-screening, including microarray comparative genomic hybridisation and sequencing of a 114 gene panel associated with cataract and congenital ophthalmic disorders was conducted by an accredited clinical laboratory. Whole exome sequencing (WES) was undertaken on a research basis and in vitro TOPflash transcriptional reporter assay was utilised to assess the impact of the putative causal variant. Results In the proband, WES revealed a novel, likely pathogenic homozygous mutation in the cadherin-associated protein beta-1 gene (CTNNB1), c.884C>G; p.(Ala295Gly), which encodes a co-effector molecule of the Wnt/β-catenin pathway. The proband’s parents were shown to be heterozygous carriers but ophthalmic examination did not detect any abnormalities. Functional assessment of the missense variant demonstrated significant reduction of β-catenin activity. Conclusions This is the first report of a biallelic disease-causing variation in CTNNB1. We conclude that this biallelic, transcriptional inactivating mutation of CTNNB1 causes a severe, syndromic form of microphthalmia, persistent foetal vasculature and vitreoretinal dysplasia that results in serious visual loss in infancy.

Background Immune-mediated haemolytic anaemia (IMHA) is a common autoimmune condition in dogs associated with a high rate of morbidity and mortality. Further work is required to understand the systemic consequences of IMHA and identify novel therapeutic targets. Hypertension is a negative prognostic indicator in people with autoimmune disease. There is increasing evidence that hypertension has an inflammatory aetiopathogenesis and responds favourably to immunosuppressive treatment. However, the prevalence and clinical signifiance of hypertension in canine IMHA has not been investigated. Study Aims Determine the prevalence of hypertension in dogs with IMHA, and the relationships of systolic blood pressure (SBP) and hypertension with short-term mortality. Design and Methods Retrospective study in university teaching veterinary hospital intensive care unit. Dogs with IMHA were compared with a control group of dogs with idiopathic epilepsy. Hypertension was defined as SBP ≥160 mmHg and severe hypertension as SBP ≥180 mmHg. Patient data, treatments and within-hospital mortality were recorded. Comparisons between IMHA and control groups were made for SBP (independent t-test) and hypertension (Fisher’s exact test). In-patient mortality was compared between hypertensive and normotensive IMHA dogs by Fisher’s exact test. Results SBP was increased in 26 dogs with IMHA (161 mmHg SD 21) compared to 23 control dogs (138 mmHg SD14; P Conclusion IMHA is a risk factor for hypertension but hypertension does not predict short-term mortality in IMHA. Hypertension in dogs may also have an inflammatory aetiology and canine IMHA has translatable potential as a naturally occurring model of hypertension in autoimmune disease.

Mutations in more than 250 genes are implicated in inherited retinal dystrophy; the encoded proteins are involved in a broad spectrum of pathways. The presence of unsolved families after highly parallel sequencing strategies suggests that further genes remain to be identified. Whole-exome and -genome sequencing studies employed here in large cohorts of affected individuals revealed biallelic mutations in ARHGEF18 in three such individuals. ARHGEF18 encodes ARHGEF18, a guanine nucleotide exchange factor that activates RHOA, a small GTPase protein that is a key component of tight junctions and adherens junctions. This biological pathway is known to be important for retinal development and function, as mutation of CRB1, encoding another component, causes retinal dystrophy. The retinal structure in individuals with ARHGEF18 mutations resembled that seen in subjects with CRB1 mutations. Five mutations were found on six alleles in the three individuals: c.808A>G (p.Thr270Ala), c.1617+5G>A (p.Asp540Glyfs ∗ 63), c.1996C>T (p.Arg666 ∗ ), c.2632G>T (p.Glu878 ∗ ), and c.2738_2761del (p.Arg913_Glu920del). Functional tests suggest that each disease genotype might retain some ARHGEF18 activity, such that the phenotype described here is not the consequence of nullizygosity. In particular, the p.Thr270Ala missense variant affects a highly conserved residue in the DBL homology domain, which is required for the interaction and activation of RHOA. Previously, knock-out of Arhgef18 in the medaka fish has been shown to cause larval lethality which is preceded by retinal defects that resemble those seen in zebrafish Crumbs complex knock-outs. The findings described here emphasize the peculiar sensitivity of the retina to perturbations of this pathway, which is highlighted as a target for potential therapeutic strategies.

Kirsty Odell, Associate and Georgina Hall, Paralegal at specialist healthcare law firm Hempsons explain what you need to do once you have incorporated a company

In the United Kingdom, genetic counsellors work together with clinical geneticists and clinical scientist colleagues within specialist genetics services, but they also often work in multidisciplinary teams (MDTs) outside of such services. There, they contribute genetic knowledge together with expert understanding of how to communicate genetic information effectively. They can offer education and support to the MDT, while providing management advice for both affected patients and the extended at-risk family members. As genomic technologies are implemented across many disciplines within healthcare, genetic counsellors are playing a key role in enabling non-genetic health professionals learn, understand and integrate genomic data into their practice. They are also involved in curriculum development, workforce planning, research, regulation and policy creation - all with the aim of ensuring a robust evidence base from which to practise, together with clear guidelines on what constitutes competence and good practice. The Association of Genetic Nurses and Counsellors (AGNC) in The United Kingdom (UK) and Republic of Ireland is committed to supporting genetic counsellors, across all sectors of healthcare and research, as they help deliver genomic medicine for the patient, family and world-class health services.European Journal of Human Genetics advance online publication, 22 March 2017; doi:10.1038/ejhg.2017.28.

Next-generation sequencing (NGS) provides diagnostic information for many rare conditions. The evolution of NGS for panel, exome, and genome testing is set to be the platform for transforming genomic diagnosis in the National Health Service (NHS). Inherited retinal dystrophies (IRDs) are a highly genetically heterogeneous disease group causing progressive visual impairment. IRDs are ideal for an NGS panel approach due to phenotypic overlap and were one of the first diagnostic panels to be developed in the NHS. While diagnostic yield for patients with IRD has improved significantly with NGS, a proportion of patients remain without a diagnosis. The clinical value of NGS testing is well understood; however, the patient experience of panel testing is not well documented. Semi-structured qualitative telephone interviews were conducted with 23 participants with IRD who had undergone NGS testing. Interviews were transcribed verbatim and analysed using interpretative phenomenological analysis. Participants’ experiences were interpreted to explore the psychosocial and service delivery impact of this testing technology, inclusive of those who received a pathogenic, negative, carrier status or variant of uncertain significance result. Collectively, three core themes were identified: (1) the journey towards a genomic diagnosis, (2) the impact of NGS testing, (3) service delivery of NGS tests. Disclosure of results had no reported adverse implications. Participants appreciated an open discussion about the potential for an uncertain or unexpected result, prior to testing. They valued pre-test counselling discussions, expert opinions and on-going care from genomic services. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (10.1007/s12687-019-00406-x) contains supplementary material, which is available to authorized users.