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BACKGROUND: Renal tubular dysgenesis (RTD) is a severe disorder with poor prognosis significantly impacting the proximal tubules of the kidney while maintaining an anatomically normal gross structure. The genetic origin of RTD, involving variants in the ACE, REN, AGT, and AGTR1 genes, affects various enzymes or receptors within the Renin angiotensin system (RAS). This condition manifests prenatally with oligohydramninos and postnatally with persistent anuria, severe refractory hypotension, and defects in skull ossification. CASE PRESENTATION: In this report, we describe a case of a female patient who, despite receiving multi vasopressor treatment, experienced persistent hypotension, ultimately resulting in early death at five days of age. While there was a history of parental consanguinity, no reported family history of renal disease existed. Blood samples from the parents and the remaining DNA sample of the patient underwent Whole Genome Sequencing (WGS). The genetic analysis revealed a rare homozygous loss of function variant (NM_000685.5; c.415C > T; p.Arg139*) in the Angiotensin II Receptor Type 1 (AGTR1) gene. CONCLUSION: This case highlights the consequence of loss-of-function variants in AGTR1 gene leading to RTD, which is characterized by high mortality rate at birth or during the neonatal period. Furthermore, we provide a comprehensive review of previously reported variants in the AGTR1 gene, which is the least encountered genetic cause of RTD, along with their associated clinical features.
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Túbulos Renales Proximales/anomalías , Receptor de Angiotensina Tipo 1 , Anomalías Urogenitales , Humanos , Femenino , Receptor de Angiotensina Tipo 1/genética , Recién Nacido , Mutación con Pérdida de Función , Resultado Fatal , Hipotensión/genéticaRESUMEN
BACKGROUND: Variants in HECW2 have recently been reported to cause a neurodevelopmental disorder with hypotonia, seizures and impaired language; however, only six variants have been reported and the clinical characteristics have only broadly been defined. METHODS: Molecular and clinical data were collected from clinical and research cohorts. Massive parallel sequencing was performed and identified individuals with a HECW2-related neurodevelopmental disorder. RESULTS: We identified 13 novel missense variants in HECW2 in 22 unpublished cases, of which 18 were confirmed to have a de novo variant. In addition, we reviewed the genotypes and phenotypes of previously reported and new cases with HECW2 variants (n=35 cases). All variants identified are missense, and the majority of likely pathogenic and pathogenic variants are located in or near the C-terminal HECT domain (88.2%). We identified several clustered variants and four recurrent variants (p.(Arg1191Gln);p.(Asn1199Lys);p.(Phe1327Ser);p.(Arg1330Trp)). Two variants, (p.(Arg1191Gln);p.(Arg1330Trp)), accounted for 22.9% and 20% of cases, respectively. Clinical characterisation suggests complete penetrance for hypotonia with or without spasticity (100%), developmental delay/intellectual disability (100%) and developmental language disorder (100%). Other common features are behavioural problems (88.9%), vision problems (83.9%), motor coordination/movement (75%) and gastrointestinal issues (70%). Seizures were present in 61.3% of individuals. Genotype-phenotype analysis shows that HECT domain variants are more frequently associated with cortical visual impairment and gastrointestinal issues. Seizures were only observed in individuals with variants in or near the HECT domain. CONCLUSION: We provide a comprehensive review and expansion of the genotypic and phenotypic spectrum of HECW2 disorders, aiding future molecular and clinical diagnosis and management.
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Discapacidad Intelectual , Trastornos del Neurodesarrollo , Ubiquitina-Proteína Ligasas , Genotipo , Humanos , Discapacidad Intelectual/genética , Hipotonía Muscular/genética , Hipotonía Muscular/patología , Trastornos del Neurodesarrollo/genética , Fenotipo , Convulsiones/genética , Ubiquitina-Proteína Ligasas/genéticaRESUMEN
OBJECTIVES: To determine the impact of genetic muscle disorders and identify the sociodemographic, illness, and symptom factors influencing quality of life. METHODS: Adults (aged 16-90 years) with a confirmed clinical or molecular diagnosis of a genetic muscle disorder identified as part of a nationwide prevalence study were invited to complete an assessment of the impact of their condition. Quality of life was measured using the World Health Organization Quality of Life questionnaire. Impact was measured via the prevalence of symptoms and comparisons of quality of life against New Zealand norms. Multivariate regression models were used to identify the most significant predictors of quality of life domains. RESULTS: 490/596 participants completed the assessment (82.2% consent rate). Quality of life was lower than the general population on physical (t = 9.37 p < 0.0001, d = 0.54) social (t = 2.27 p = 0.02, d = 0.13) and environmental domains (t = 2.28 p = 0.02, d = 0.13), although effect sizes were small. No difference was found on the psychological domain (t = - 1.17 p = 0.24, d = 0.07). Multivariate regression models (predicting 42%-64% of the variance) revealed personal factors (younger age, being in employment and in a relationship), symptoms (lower pain, fatigue, and sleep difficulties), physical health (no need for ventilation support, fewer activity limitations and no comorbidities), and psychosocial factors (lower depression, anxiety, behavioural dyscontrol and higher self-efficacy, satisfaction with health care and social support) contributed to improved quality of life. CONCLUSIONS: A range of factors influence the quality of life in adults diagnosed with a genetic muscle disorder and some may serve as targets for multi-faceted intervention.
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Enfermedades Musculares , Calidad de Vida , Adulto , Ansiedad/psicología , Trastornos de Ansiedad , Depresión/psicología , Humanos , Calidad de Vida/psicología , Encuestas y CuestionariosRESUMEN
BACKGROUND: Möbius (Moebius) and Poland's syndromes are two rare congenital syndromes characterized by non-progressive bilateral (and often asymmetric) dysfunction of the 6th and 7th cranial nerves and hypoplasia of the pectoral muscles associated with chest wall and upper limb anomalies respectively. Manifest simultaneously as Poland-Möbius (Poland-Moebius) syndrome, debate continues as to whether this is a distinct nosological entity or represents phenotypic variation as part of a spectrum of disorders of rhomboencephalic development. Etiological hypotheses implicate both genetic and environmental factors. The PLXND1 gene codes for a protein expressed in the fetal central nervous system and vascular endothelium and is thus involved in embryonic neurogenesis and vasculogenesis. It is located at chromosome region 3q21-q22, a locus of interest for Möbius syndrome. CASE PRESENTATION: We present the first report of a patient with Poland-Möbius syndrome and a mutation in the PLXND1 gene. A child with Poland-Möbius syndrome and a maternally inherited missense variant (NM_015103.2:ex14:c.2890G > Ap.V964M) in the PLXND1 gene is described. In order to contextualize these findings, the literature was examined to identify other confirmed cases of Poland-Möbius syndrome for which genetic data were available. Fourteen additional cases of Poland-Möbius syndrome with genetic studies are described in the literature. None implicated the PLXND1 gene which has previously been implicated in isolated Möbius syndrome. CONCLUSIONS: This report provides further evidence in support of a role for PLXND1 mutations in Möbius syndrome and reasserts the nosological link between Möbius and Poland's syndromes. LEVEL OF EVIDENCE: Level V, Descriptive Study.
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Síndrome de Mobius , Síndrome de Poland , Pared Torácica , Niño , Humanos , Síndrome de Mobius/diagnóstico , Síndrome de Mobius/genética , Síndrome de Mobius/complicaciones , Síndrome de Poland/diagnóstico , Síndrome de Poland/genética , Síndrome de Poland/complicaciones , Mutación , Sistema Nervioso CentralRESUMEN
PURPOSE: Human serine/threonine kinase 4 (STK4) deficiency is a rare, autosomal recessive genetic disorder leading to combined immunodeficiency; however, the extent to which immune signaling and host defense are impaired is unclear. We assessed the functional consequences of a novel, homozygous nonsense STK4 mutation (NM_006282.2:c.871C > T, p.Arg291*) identified in a pediatric patient by comparing his innate and adaptive cell-mediated and humoral immune responses with those of three heterozygous relatives and unrelated controls. METHODS: The genetic etiology was verified by whole genome and Sanger sequencing. STK4 gene and protein expression was measured by quantitative RT-PCR and immunoblotting, respectively. Cellular abnormalities were assessed by high-throughput RT-RCR, RNA-Seq, ELISA, and flow cytometry. Antibody responses were assessed by ELISA and phage immunoprecipitation-sequencing. RESULTS: The patient exhibited partial loss of STK4 expression and complete loss of STK4 function combined with recurrent viral and bacterial infections, notably persistent Epstein-Barr virus viremia and pulmonary tuberculosis. Cellular and molecular analyses revealed abnormal fractions of T cell subsets, plasmacytoid dendritic cells, and NK cells. The transcriptional responses of the patient's whole blood and PBMC samples indicated dysregulated interferon signaling, impaired T cell immunity, and increased T cell apoptosis as well as impaired regulation of cytokine-induced adhesion and leukocyte chemotaxis genes. Nonetheless, the patient had detectable vaccine-specific antibodies and IgG responses to various pathogens, consistent with a normal CD19 + B cell fraction, albeit with a distinctive antibody repertoire, largely driven by herpes virus antigens. CONCLUSION: Patients with STK4 deficiency can exhibit broad impairment of immune function extending beyond lymphoid cells.
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Síndromes de Inmunodeficiencia/genética , Péptidos y Proteínas de Señalización Intracelular/genética , Proteínas Serina-Treonina Quinasas/genética , Anticuerpos Antibacterianos/sangre , Anticuerpos Antivirales/sangre , Adhesión Celular/genética , Quimiotaxis/genética , Citocinas/genética , Células Dendríticas/inmunología , Infecciones por Virus de Epstein-Barr/sangre , Infecciones por Virus de Epstein-Barr/genética , Humanos , Síndromes de Inmunodeficiencia/sangre , Péptidos y Proteínas de Señalización Intracelular/deficiencia , Células Asesinas Naturales/inmunología , Masculino , Mutación , Proteínas Serina-Treonina Quinasas/deficiencia , Linfocitos T/inmunología , Transcriptoma , Tuberculosis Pulmonar/sangre , Tuberculosis Pulmonar/genéticaRESUMEN
BACKGROUND: Lung cancer is a major cause of death in New Zealand. In recent years, targeted therapies have improved outcomes. AIM: To determine the uptake of anaplastic lymphoma kinase (ALK) testing, and the prevalence, demographic profile and outcomes of ALK-positive non-small-cell lung cancer (NSCLC), in New Zealand, where no national ALK-testing guidelines or subsidised ALK tyrosine kinase inhibitor (TKI) therapies are available. METHODS: A population-based observational study reviewed databases to identify patients presenting with non-squamous NSCLC over 6.5 years in northern New Zealand. We report the proportion tested for ALK gene rearrangements and the results. NSCLC samples tested by fluorescence in situ hybridisation were retested by next generation sequencing and ALK immunohistochemistry. A survival analysis compared ALK-positive patients treated or not treated with ALK TKI therapy. RESULTS: From a total of 3130 patients diagnosed with non-squamous NSCLC, 407 (13%) were tested for ALK gene rearrangements, and patient selection was variable and inequitable. Among those tested, 34 (8.4%) had ALK-positive NSCLC. ALK-positive disease was more prevalent in younger versus older patients, non-smokers versus smokers and in Maori, Pacific or Asian ethnic groups than in New Zealand Europeans. Fluorescence in situ hybridisation, ALK immunohistochemistry and next generation sequencing showed broad concordance for detecting ALK-positive disease under local testing conditions. Among patients with ALK-positive metastatic NSCLC, those treated with ALK TKI survived markedly longer than those not treated with ALK TKI (median overall survival 5.12 vs 0.55 years). CONCLUSION: Lung cancer outcomes in New Zealand may be improved by providing national guidelines and funding policy for ALK testing and access to subsidised ALK TKI therapy.
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Carcinoma de Pulmón de Células no Pequeñas , Neoplasias Pulmonares , Quinasa de Linfoma Anaplásico/genética , Carcinoma de Pulmón de Células no Pequeñas/tratamiento farmacológico , Carcinoma de Pulmón de Células no Pequeñas/genética , Detección Precoz del Cáncer , Reordenamiento Génico , Humanos , Neoplasias Pulmonares/diagnóstico , Neoplasias Pulmonares/tratamiento farmacológico , Neoplasias Pulmonares/epidemiología , Nueva Zelanda/epidemiología , Inhibidores de Proteínas Quinasas , Proteínas Tirosina Quinasas Receptoras/genéticaRESUMEN
OBJECTIVE: To review the experience of a pharmacist-led interprofessional attention deficit hyperactivity disorder (ADHD) clinic in a large integrated health care system. PRACTICE DESCRIPTION: Kaiser Permanente Northwest (KPNW) is a nonprofit managed health care system that provides integrated care to more than 625,000 members in Oregon and southwest Washington. Most health care encounters occur within KPNW facilities and with KPNW health professionals or support staff using a common electronic medical record. PRACTICE INNOVATION: A team-based adult ADHD service was implemented with collaboration among the mental health, primary care, and pharmacy departments. EVALUATION: The patients were assessed by a psychiatrist for diagnosis and care guidance. METHODS: A pharmacist, working under the collaborative drug therapy management partnership, then initiated and managed the patient's medications through telephone encounters until the patient was stable. The care of the patient was then transitioned back to primary care and not added to psychiatry's caseload. RESULTS: A total of 914 patients were treated by the adult ADHD clinic since the initiation of the service in the fall of 2015. Of these patients, 610 were stabilized successfully by the ADHD clinic pharmacists. The ADHD clinic pharmacists conducted 2634 patient encounters over the study period and averaged 3.7 telephone follow-ups per successful patient, with follow-ups approximately every 2 weeks. The organization realized a cost savings of $761,280 during this time period on the basis of the cost of a mental health provider adjusting and addressing ADHD medications versus pharmacy staff working to stabilize the patient. CONCLUSION: The implementation of a collaborative adult ADHD service has demonstrated a successful alliance of primary care, mental health, and pharmacy in a large managed care organization. In addition to increased efficiency and evidence-based practice, the adult ADHD clinic resulted in cost savings and improved access to mental health care.
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Trastorno por Déficit de Atención con Hiperactividad , Servicios Farmacéuticos , Adulto , Trastorno por Déficit de Atención con Hiperactividad/tratamiento farmacológico , Humanos , Administración del Tratamiento Farmacológico , Oregon , Farmacéuticos , WashingtónRESUMEN
BACKGROUND: Sudden cardiac death among children and young adults is a devastating event. We performed a prospective, population-based, clinical and genetic study of sudden cardiac death among children and young adults. METHODS: We prospectively collected clinical, demographic, and autopsy information on all cases of sudden cardiac death among children and young adults 1 to 35 years of age in Australia and New Zealand from 2010 through 2012. In cases that had no cause identified after a comprehensive autopsy that included toxicologic and histologic studies (unexplained sudden cardiac death), at least 59 cardiac genes were analyzed for a clinically relevant cardiac gene mutation. RESULTS: A total of 490 cases of sudden cardiac death were identified. The annual incidence was 1.3 cases per 100,000 persons 1 to 35 years of age; 72% of the cases involved boys or young men. Persons 31 to 35 years of age had the highest incidence of sudden cardiac death (3.2 cases per 100,000 persons per year), and persons 16 to 20 years of age had the highest incidence of unexplained sudden cardiac death (0.8 cases per 100,000 persons per year). The most common explained causes of sudden cardiac death were coronary artery disease (24% of cases) and inherited cardiomyopathies (16% of cases). Unexplained sudden cardiac death (40% of cases) was the predominant finding among persons in all age groups, except for those 31 to 35 years of age, for whom coronary artery disease was the most common finding. Younger age and death at night were independently associated with unexplained sudden cardiac death as compared with explained sudden cardiac death. A clinically relevant cardiac gene mutation was identified in 31 of 113 cases (27%) of unexplained sudden cardiac death in which genetic testing was performed. During follow-up, a clinical diagnosis of an inherited cardiovascular disease was identified in 13% of the families in which an unexplained sudden cardiac death occurred. CONCLUSIONS: The addition of genetic testing to autopsy investigation substantially increased the identification of a possible cause of sudden cardiac death among children and young adults. (Funded by the National Health and Medical Research Council of Australia and others.).
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Enfermedades Cardiovasculares/genética , Causas de Muerte , Muerte Súbita Cardíaca/epidemiología , Pruebas Genéticas , Adolescente , Adulto , Distribución por Edad , Factores de Edad , Australia/epidemiología , Autopsia , Enfermedades Cardiovasculares/mortalidad , Niño , Preescolar , Femenino , Predisposición Genética a la Enfermedad , Humanos , Incidencia , Lactante , Recién Nacido , Masculino , Nueva Zelanda/epidemiología , Estudios Prospectivos , Adulto JovenRESUMEN
BACKGROUND: Previous epidemiological studies of genetic muscle disorders have relied on medical records to identify cases and may be at risk of selection biases or have focused on selective population groups. OBJECTIVES: This study aimed to determine age-standardised prevalence of genetic muscle disorders through a nationwide, epidemiological study across the lifespan using the capture-recapture method. METHODS: Adults and children with a confirmed clinical or molecular diagnosis of a genetic muscle disorder, resident in New Zealand on April 1, 2015 were identified using multiple overlapping sources. Genetic muscle disorders included the muscular dystrophies, congenital myopathies, ion channel myopathies, GNE myopathy, and Pompe disease. Prevalence per 100,000 persons by age, sex, disorder, ethnicity and geographical region with 95% CIs was calculated using Poisson distribution. Direct standardisation was applied to age-standardise prevalence to the world population. Completeness of case ascertainment was determined using capture-recapture modelling. RESULTS: Age standardised minimal point prevalence of all genetic muscle disorders was 22.3 per 100,000 (95% CI 19.5-25.6). Prevalence in Europeans of 24.4 per 100,000, (95% CI 21.1-28.3) was twice that observed in NZ's other 3 main ethnic groups; Maori (12.6 per 100,000, 95% CI 7.8-20.5), Pasifika (11.0 per 100,000, 95% CI 5.4-23.3), and Asian (9.13 per 100,000, 95% CI 5.0-17.8). Crude prevalence of myotonic dystrophy was 3 times higher in Europeans (10.5 per 100,000, 9.4-11.8) than Maori and Pasifika (2.5 per 100,000, 95% CI 1.5-4.2 and 0.7 per 100,000, 95% CI 0.1-2.7 respectively). There were considerable regional variations in prevalence, although there was no significant association with social deprivation. The final capture-recapture model, with the least deviance, estimated the study ascertained 99.2% of diagnosed cases. CONCLUSIONS: Ethnic and regional differences in the prevalence of genetic muscle disorders need to be considered in service delivery planning, evaluation, and decision making.
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Enfermedades Musculares/etnología , Enfermedades Musculares/genética , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Niño , Preescolar , Femenino , Humanos , Lactante , Masculino , Persona de Mediana Edad , Enfermedades Musculares/diagnóstico , Nueva Zelanda/etnología , Vigilancia de la Población/métodos , Prevalencia , Adulto JovenRESUMEN
BACKGROUND: We aimed to determine the mutation yield and clinical applicability of "molecular autopsy" following sudden arrhythmic death syndrome (SADS) by validating and utilizing low-cost high-throughput technologies: Fluidigm Access Array PCR-enrichment with Illumina HiSeq 2000 next generation sequencing (NGS). METHODS: We validated and optimized the NGS platform with a subset of 46 patients by comparison with Sanger sequencing of coding exons of major arrhythmia risk-genes (KCNQ1, KCNH2, SCN5A, KCNE1, KCNE2, RYR2). A combined large multi-ethnic international SADS cohort was sequenced utilizing the NGS platform to determine overall molecular yield; rare variants identified by NGS were subsequently reconfirmed by Sanger sequencing. RESULTS: The NGS platform demonstrated 100% sensitivity for pathogenic variants as well as 87.20% sensitivity and 99.99% specificity for all substitutions (optimization subset, n = 46). The positive predictive value (PPV) for NGS for rare substitutions was 16.0% (27 confirmed rare variants of 169 positive NGS calls in 151 additional cases). The overall molecular yield in 197 multi-ethnic SADS cases (mean age 22.6 ± 14.4 years, 68% male) was 5.1% (95% confidence interval 2.0-8.1%), representing 10 cases carrying pathogenic or likely pathogenic risk-mutations. CONCLUSIONS: Molecular autopsy with Fluidigm Access Array and Illumina HiSeq NGS utilizing a selected panel of LQTS/BrS and CPVT risk-genes offers moderate diagnostic yield, albeit requiring confirmatory Sanger-sequencing of mutational variants.
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Arritmias Cardíacas/genética , Autopsia/métodos , Análisis Mutacional de ADN , Muerte Súbita Cardíaca/etiología , Secuenciación de Nucleótidos de Alto Rendimiento , Técnicas Analíticas Microfluídicas , Mutación , Patología Molecular , Reacción en Cadena de la Polimerasa , Adolescente , Adulto , Arritmias Cardíacas/diagnóstico , Arritmias Cardíacas/mortalidad , Australia , Causas de Muerte , Niño , Preescolar , Europa (Continente) , Femenino , Predisposición Genética a la Enfermedad , Herencia , Humanos , Lactante , Masculino , Nueva Zelanda , Linaje , Valor Predictivo de las Pruebas , Reproducibilidad de los Resultados , Factores de Riesgo , Adulto JovenRESUMEN
Very long chain acyl-CoA dehydrogenase deficiency (VLCADD, OMIM #201475) has been increasingly diagnosed since the advent of expanded newborn screening (NBS). Elevated levels of tetradecenoyl-L-carnitine (C14:1) in newborn screening blood spot samples are particularly common in New Zealand, however this has not translated into increased VLCADD clinical presentations. A high proportion of screen-positive cases in NZ are of Maori or Pacific ethnicity and positive for the c.1226C > T (p.Thr409Met) ACADVL gene variant. We performed a retrospective, blinded, case-control study of 255 cases, born between 2006 and 2013, with elevated NBS C14:1 levels between 0.9 and 2.4 µmol/L, below the NZ C14:1 notification cut-off of 2.5 µmol/L. Coded healthcare records were audited for cases and age- and ethnicity- matched controls. The clinical records of those with possible VLCADD-related symptoms were reviewed. The follow-up period was 6 months to 7 years. Two of 247 cases (0.8 %) had possible VLCADD-like symptoms while four of 247 controls (2 %) had VLCADD-like symptoms (p = 0.81). Maori were overrepresented (68 % of the cohort vs 15 % of population). Targeted analysis of the c.1226 locus revealed the local increase in screening C14:1 levels is associated with the c.1226C > T variant (97/152 alleles tested), found predominantly in Maori and Pacific people. There was no increase in clinically significant childhood disease, irrespective of ethnicity. The study suggests that children with elevated C14:1, between 0.9-2.4 µmol/L, on NBS are at very low risk of clinically significant childhood disease. A minimally interventional approach to managing these patients is indicated, at least in the New Zealand population.
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Acil-CoA Deshidrogenasa de Cadena Larga/deficiencia , Carnitina/sangre , Errores Innatos del Metabolismo Lipídico/sangre , Errores Innatos del Metabolismo Lipídico/diagnóstico , Enfermedades Mitocondriales/sangre , Enfermedades Mitocondriales/diagnóstico , Enfermedades Musculares/sangre , Enfermedades Musculares/diagnóstico , Acil-CoA Deshidrogenasa de Cadena Larga/sangre , Estudios de Casos y Controles , Síndromes Congénitos de Insuficiencia de la Médula Ósea , Femenino , Humanos , Recién Nacido , Errores Innatos del Metabolismo Lipídico/tratamiento farmacológico , Masculino , Enfermedades Mitocondriales/tratamiento farmacológico , Enfermedades Musculares/tratamiento farmacológico , Tamizaje Neonatal , Nueva Zelanda , Estudios RetrospectivosRESUMEN
Two male siblings from a consanguineous union presented in early infancy with marked truncal hypotonia, a general paucity of movement, extrapyramidal signs and cognitive delay. By mid-childhood they had made little developmental progress and remained severely hypotonic and bradykinetic. They developed epilepsy and had problems with autonomic dysfunction and oculogyric crises. They had a number of orthopaedic problems secondary to their hypotonia. Cerebrospinal fluid (CSF) neurotransmitters were initially normal, apart from mildly elevated 5-hydroxyindolacetic acid, and the children did not respond favourably to a trial of levodopa-carbidopa. The youngest died from respiratory complications at 10 years of age. Repeat CSF neurotransmitters in the older sibling at eight years of age showed slightly low homovanillic acid and 5-hydroxyindoleacetic acid levels. Whole-exome sequencing revealed a novel mutation homozygous in both children in the monoamine transporter gene SLC18A2 (p.Pro237His), resulting in brain dopamine-serotonin vesicular transport disease. This is the second family to be described with a mutation in this gene. Treatment with the dopamine agonist pramipexole in the surviving child resulted in mild improvements in alertness, communication, and eye movements. This case supports the identification of the causal mutation in the original case, expands the clinical phenotype of brain dopamine-serotonin vesicular transport disease and confirms that pramipexole treatment may lead to symptomatic improvement in affected individuals.
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Encefalopatías/genética , Encefalopatías/metabolismo , Encéfalo/metabolismo , Dopamina/metabolismo , Trastornos Parkinsonianos/genética , Trastornos Parkinsonianos/metabolismo , Serotonina/metabolismo , Encéfalo/efectos de los fármacos , Encefalopatías/tratamiento farmacológico , Carbidopa/uso terapéutico , Niño , Humanos , Levodopa/uso terapéutico , Masculino , Trastornos Parkinsonianos/tratamiento farmacológico , Polimorfismo de Nucleótido Simple/genéticaRESUMEN
BACKGROUND: Long QT syndrome (LQTS) is an autosomal dominant condition predisposing to sudden death from malignant arrhythmia. Genetic testing identifies many missense single nucleotide variants of uncertain pathogenicity. Establishing genetic pathogenicity is an essential prerequisite to family cascade screening. Many laboratories use in silico prediction tools, either alone or in combination, or metaservers, in order to predict pathogenicity; however, their accuracy in the context of LQTS is unknown. We evaluated the accuracy of five in silico programs and two metaservers in the analysis of LQTS 1-3 gene variants. METHODS: The in silico tools SIFT, PolyPhen-2, PROVEAN, SNPs&GO and SNAP, either alone or in all possible combinations, and the metaservers Meta-SNP and PredictSNP, were tested on 312 KCNQ1, KCNH2 and SCN5A gene variants that have previously been characterised by either in vitro or co-segregation studies as either "pathogenic" (283) or "benign" (29). The accuracy, sensitivity, specificity and Matthews Correlation Coefficient (MCC) were calculated to determine the best combination of in silico tools for each LQTS gene, and when all genes are combined. RESULTS: The best combination of in silico tools for KCNQ1 is PROVEAN, SNPs&GO and SIFT (accuracy 92.7%, sensitivity 93.1%, specificity 100% and MCC 0.70). The best combination of in silico tools for KCNH2 is SIFT and PROVEAN or PROVEAN, SNPs&GO and SIFT. Both combinations have the same scores for accuracy (91.1%), sensitivity (91.5%), specificity (87.5%) and MCC (0.62). In the case of SCN5A, SNAP and PROVEAN provided the best combination (accuracy 81.4%, sensitivity 86.9%, specificity 50.0%, and MCC 0.32). When all three LQT genes are combined, SIFT, PROVEAN and SNAP is the combination with the best performance (accuracy 82.7%, sensitivity 83.0%, specificity 80.0%, and MCC 0.44). Both metaservers performed better than the single in silico tools; however, they did not perform better than the best performing combination of in silico tools. CONCLUSIONS: The combination of in silico tools with the best performance is gene-dependent. The in silico tools reported here may have some value in assessing variants in the KCNQ1 and KCNH2 genes, but caution should be taken when the analysis is applied to SCN5A gene variants.
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Biología Computacional/métodos , Simulación por Computador , Síndrome de QT Prolongado/genética , Mutación , Canal de Potasio ERG1 , Canales de Potasio Éter-A-Go-Go/genética , Humanos , Canal de Potasio KCNQ1/genética , Canal de Sodio Activado por Voltaje NAV1.5/genética , Polimorfismo de Nucleótido SimpleRESUMEN
INTRODUCTION: The accurate prediction of the risk of sudden cardiac death (SCD) in hypertrophic cardiomyopathy (HCM) remains elusive. Corrected QT interval (QTc) duration is a known risk factor in various cardiac conditions. Single nucleotide polymorphisms (SNPs) have been linked to QTc length, and to SCD. Here we investigated the role of 21 candidate SNPs in QTc duration and SCD events in patients with HCM. METHODS AND RESULTS: This HCM registry-based study included patients with an ECG, medical history, first SCD event data, and DNA available. Each individual SNP was assessed using logistic regression for associations with 2 outcomes: a prolonged QTc ( ≥440 milliseconds), and first SCD event (SCD, resuscitated cardiac arrest, and appropriate implantable cardioverter defibrillator (ICD) shock for ventricular fibrillation/ventricular tachycardia (VF/VT). In 272 HCM patients, there were 31 SCD events (8 SCD, 9 resuscitated cardiac arrest, 14 ICD shocks for VF/VT; 11%). A QTc ≥ 500 milliseconds was associated with SCD events on multivariate analysis (odds ratio [OR] = 4.0, 95% confidence interval [CI], 1.19-12.02, P = 0.016). In 228 Caucasian patients, 2 SNPs in the NOS1AP gene (rs10494366 and rs12143842) were associated with a prolonged QTc after correction for multiple testing. This remained significant after adjustment for current age, sex, and ≥1 SCD risk factor (OR 1.59 per copy of the minor allele, 95% CI 1.08-2.39, P = 0.022, and OR 1.63, 95% CI 1.09-2.49, P = 0.020, respectively). No SNPs were directly associated with SCD events. CONCLUSION: SNPs in the NOS1AP gene influence QTc interval duration but we have not demonstrated a direct association with the risk of SCD.
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Proteínas Adaptadoras Transductoras de Señales/genética , Cardiomiopatía Hipertrófica/genética , Cardiomiopatía Hipertrófica/fisiopatología , Paro Cardíaco/etiología , Paro Cardíaco/genética , Síndrome de QT Prolongado/genética , Síndrome de QT Prolongado/fisiopatología , Anciano , Cardiomiopatía Hipertrófica/epidemiología , Estudios de Cohortes , ADN/genética , Muerte Súbita Cardíaca , Desfibriladores Implantables , Electrocardiografía , Femenino , Paro Cardíaco/epidemiología , Humanos , Síndrome de QT Prolongado/epidemiología , Masculino , Persona de Mediana Edad , Nueva Zelanda/epidemiología , Polimorfismo de Nucleótido Simple , Riesgo , Resultado del TratamientoRESUMEN
Disorders of mitochondrial function are a collectively common group of genetic diseases in which deficits in core mitochondrial translation machinery, including aminoacyl tRNA synthetases, are key players. Biallelic variants in the CARS2 gene (NM_024537.4), which encodes the mitochondrial aminoacyl-tRNA synthetase for cysteine (CARS2, mt-aaRScys; MIM*612800), result in childhood onset epileptic encephalopathy and complex movement disorder with combined oxidative phosphorylation deficiency (MIM#616672). Prior to this report, eight unique pathogenic variants in the CARS2 gene had been reported in seven individuals. Here, we describe a male who presented in the third week of life with apnoea. He rapidly deteriorated with paroxysmal dystonic crises and apnoea resulting in death at 16 weeks. He had no evidence of seizure activity or multisystem disease and had normal brain imaging. Skeletal muscle biopsy revealed a combined disorder of oxidative phosphorylation. Whole-exome sequencing identified biallelic variants in the CARS2 gene: one novel (c.1478T>C, p.Phe493Ser), and one previously reported (c.655G>A, p.Ala219Thr; rs727505361). Northern blot analysis of RNA isolated from the patient's fibroblasts confirmed a clear defect in aminoacylation of the mitochondrial tRNA for cysteine (mt-tRNACys). To our knowledge, this is the earliest reported case of CARS2 deficiency with severe, early onset dystonia and apnoea, without epilepsy.
RESUMEN
CONTEXT: Monogenic obesity is a rare form of obesity due to pathogenic variants in genes implicated in the leptin-melanocortin signaling pathway and accounts for around 5% of severe early-onset obesity. Mutations in the genes encoding the MC4R, leptin, and leptin receptor are commonly reported in various populations to cause monogenic obesity. Determining the genetic cause has important clinical benefits as novel therapeutic interventions are now available for some forms of monogenic obesity. OBJECTIVE: To unravel the genetic causes of early-onset obesity in the population of Qatar. METHODS: In total, 243 patients with early-onset obesity (above the 95% percentile) and age of onset below 10 years were screened for monogenic obesity variants using a targeted gene panel, consisting of 52 obesity-related genes. RESULTS: Thirty rare variants potentially associated with obesity were identified in 36 of 243 (14.8%) probands in 15 candidate genes (LEP, LEPR, POMC, MC3R, MC4R, MRAP2, SH2B1, BDNF, NTRK2, DYRK1B, SIM1, GNAS, ADCY3, RAI1, and BBS2). Twenty-three of the variants identified were novel to this study and the rest, 7 variants, were previously reported in literature. Variants in MC4R were the most common cause of obesity in our cohort (19%) and the c.485C>T p.T162I variant was the most frequent MC4R variant seen in 5 patients. CONCLUSION: We identified likely pathogenic/pathogenic variants that seem to explain the phenotype of around 14.8% of our cases. Variants in the MC4R gene are the commonest cause of early-onset obesity in our population. Our study represents the largest monogenic obesity cohort in the Middle East and revealed novel obesity variants in this understudied population. Functional studies will be required to elucidate the molecular mechanism of their pathogenicity.
Asunto(s)
Leptina , Obesidad , Humanos , Niño , Leptina/genética , Qatar/epidemiología , Obesidad/epidemiología , Obesidad/genética , Obesidad/patología , Mutación , Fenotipo , Receptor de Melanocortina Tipo 4/genética , Proteínas Adaptadoras Transductoras de Señales/genéticaRESUMEN
The zebrafish (Danio rerio) has become an attractive model for human disease modeling as there are a large number of orthologous genes that encode similar proteins to those found in humans. The number of tools available to manipulate the zebrafish genome is limited and many currently used techniques are only effective during early development (such as morpholino-based antisense technology) or it is phenotypically driven and does not offer targeted gene knockdown (such as chemical mutagenesis). The use of RNA interference has been met with controversy as off-target effects can make interpreting phenotypic outcomes difficult; however, this has been resolved by creating zebrafish lines that contain stably integrated miRNA constructs that target the desired gene of interest. In this study, we show that a commercially available miRNA vector system with a mouse-derived miRNA backbone is functional in zebrafish and is effective in causing eGFP knockdown in a transient in vivo eGFP sensor assay system. We chose to apply this system to the knockdown of transcripts that are implicated in the human cardiac disorder, Long QT syndrome.
Asunto(s)
Técnicas de Silenciamiento del Gen/métodos , MicroARNs/genética , Proteínas de Pez Cebra/genética , Análisis de Varianza , Animales , Modelos Animales de Enfermedad , Embrión no Mamífero , Canales de Potasio Éter-A-Go-Go/genética , Canales de Potasio Éter-A-Go-Go/metabolismo , Proteínas Fluorescentes Verdes/genética , Proteínas Fluorescentes Verdes/metabolismo , Humanos , Síndrome de QT Prolongado , Ratones , MicroARNs/química , Interferencia de ARN , Pez Cebra , Proteínas de Pez Cebra/metabolismoRESUMEN
Inflammatory bowel disease (IBD) is a collective term for conditions characterised by chronic inflammation of the gastrointestinal tract involving an inappropriate immune response to commensal micro-organisms in a genetically susceptible host. Previously, aqueous and ethyl acetate extracts of gold kiwifruit (Actinidia chinensis) or green kiwifruit (A. deliciosa) have demonstrated anti-inflammatory activity using in vitro models of IBD. The present study examined whether these kiwifruit extracts (KFE) had immune-modulating effects in vivo against inflammatory processes that are known to be increased in patients with IBD. KFE were used as a dietary intervention in IL-10-gene-deficient (Il10(-/-)) mice (an in vivo model of IBD) and the C57BL/6J background strain in a 3 × 2 factorial design. While all Il10(-/-) mice developed significant colonic inflammation compared with C57BL/6J mice, this was not affected by the inclusion of KFE in the diet. These findings are in direct contrast to our previous study where KFE reduced inflammatory signalling in primary cells isolated from Il10(-/-) and C57BL/6J mice. Whole-genome gene and protein expression level profiling indicated that KFE influenced immune signalling pathways and metabolic processes within the colonic tissue; however, the effects were subtle. In particular, expression levels across gene sets related to adaptive immune pathways were significantly reduced using three of the four KFE in C57BL/6J mice. The present study highlights the importance of investigating food components identified by cell-based assays with appropriate in vivo models before making dietary recommendations, as a food that looks promising in vitro may not be effective in vivo.
Asunto(s)
Actinidia/química , Colon/efectos de los fármacos , Frutas/química , Interleucina-10/genética , Interleucina-10/metabolismo , Extractos Vegetales/farmacología , Animales , Colon/metabolismo , Perfilación de la Expresión Génica , Regulación de la Expresión Génica/efectos de los fármacos , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Análisis de Secuencia por Matrices de Oligonucleótidos , Extractos Vegetales/química , Proteínas/clasificación , Proteínas/genética , Proteínas/metabolismo , ARN Mensajero/metabolismo , Reacción en Cadena de la Polimerasa de Transcriptasa InversaRESUMEN
Real-time in vivo imaging of cell migration and behavior has advanced our understanding of physiological processes in situ, especially in the field of immunology. We carried out the transplantation of a mixed population of blood cells from adult zebrafish (Danio rerio) to 2 day old embryos. The blood cells were treated ex vivo with Function-Spacer-Lipid constructs (FSL) incorporating either fluorescein or Atto488 fluorophores (FSL-FLRO4-I or -II). Excellent labeling efficiency was demonstrated by epifluorescence microscopy and FACScan analysis. Real-time video imaging of the recipient fish showed that the functionality of these cells was retained and not affected by the labeling. The usefulness of FSL-FLRO4-I as a contrast agent in microangiography was explored. Overall, we found both FSL-FLRO4-I and-II promising labeling dyes for real-time in vivo imaging in zebrafish.