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BACKGROUND: Malignant hyperthermia (MH) is a rare pharmacogenetic disorder that can lead to a life-threatening reaction during general anaesthesia with triggering agents. Prompt life-saving treatment includes the immediate administration of the antidote dantrolene. This study investigated Swedish healthcare providers' awareness and adherence to guidelines and recommendations with respect to MH and whether adherence to safe MH-praxis varies with hospital care-complexity level and private versus public management form. METHOD: Agreements and procurement specifications between all 21 Swedish County Councils and privately run surgical care providers were reviewed alongside with questionnaire-aided collection of information from 62 publicly funded health care providers (both privately and publicly run). RESULTS: No procurement requirement specification or contract contained requirements on anaesthesia or aspects of MH. All publicly run hospitals stocked dantrolene and 28 out of 52 (54%) stocked the recommended amount. Seven out of nine (78%) of the privately run institutions stocked dantrolene, and one stocked the recommended amount. Publicly run hospitals adhered to recommendations to a greater extent than privately run institutions, both with respect to stocking of dantrolene (p = .02) and to stocking the recommended amount (p = .03). CONCLUSIONS: Contracts between Swedish county councils and private surgical care subcontractors rarely outline expectations of standards for the safe practice of anaesthesia such as preparedness to handle a life-threatening MH reaction. Among Swedish publicly funded anaesthesia providers there is room for improvement in adherence to the EMHG guideline on dantrolene availability. Publicly run hospitals seem to have better compliance with these recommendations than privately run institutions. Raising awareness about current guidelines is important to improve safety for known and unknown MH-susceptible individuals.
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Dantroleno , Adhesión a Directriz , Hipertermia Maligna , Humanos , Suecia , Dantroleno/uso terapéutico , Adhesión a Directriz/estadística & datos numéricos , Encuestas y Cuestionarios , Relajantes Musculares CentralesRESUMEN
Genetic research has identified a large number of genetic variants, both rare and common, underlying neurodevelopmental disorders (NDD) and major psychiatric disorders. Currently, these findings are being translated into clinical practice. However, there is a lack of knowledge and guidelines for psychiatric genetic testing (PsychGT) and genetic counseling (PsychGC). The European Union-funded COST action EnGagE (CA17130) network was started to investigate the current implementation status of PsychGT and PsychGC across 35 participating European countries. Here, we present the results of a pan-European online survey in which we gathered the opinions, knowledge, and practices of a self-selected sample of professionals involved/interested in the field. We received answers from 181 respondents. The three main occupational categories were genetic counselor (21.0%), clinical geneticist (24.9%), and researcher (25.4%). Of all 181 respondents, 106 provide GC for any psychiatric disorder or NDD, corresponding to 58.6% of the whole group ranging from 43.2% in Central Eastern Europe to 66.1% in Western Europe. Overall, 65.2% of the respondents reported that genetic testing is offered to individuals with NDD, and 26.5% indicated the same for individuals with major psychiatric disorders. Only 22.1% of the respondents indicated that they have guidelines for PsychGT. Pharmacogenetic testing actionable for psychiatric disorders was offered by 15%. Interestingly, when genetic tests are fully covered by national health insurance, more genetic testing is provided for individuals with NDD but not those with major psychiatric disorders. Our qualitative analyses of responses highlight the lack of guidelines and knowledge on utilizing and using genetic tests and education and training as the major obstacles to implementation. Indeed, the existence of psychiatric genetic training courses was confirmed by only 11.6% of respondents. The question on the relevance of up-to-date education and training in psychiatric genetics on everyday related practice was highly relevant. We provide evidence that PsychGC and PsychGT are already in use across European countries, but there is a lack of guidelines and education. Harmonization of practice and development of guidelines for genetic counseling, testing, and training professionals would improve equality and access to quality care for individuals with psychiatric disorders within Europe.
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Asesoramiento Genético , Pruebas Genéticas , Humanos , Asesoramiento Genético/métodos , Pruebas Genéticas/métodos , Encuestas y Cuestionarios , Europa (Continente) , Unión EuropeaRESUMEN
Whole genome sequencing (WGS) has the potential to be a comprehensive genetic test, especially relevant for individuals with neurodevelopmental disorders, syndromes and congenital malformations. However, the cost consequences of using whole genome sequencing as a first-line genetic test for these individuals are not well understood. The study objective was to compare the healthcare costs and diagnostic yield when WGS is performed as the first-line test instead of chromosomal microarray analysis (CMA). Two cohorts were analyzed retrospectively using register data, cohort CMA (418 patients referred for CMA at the department of Clinical Genetics, Karolinska University Hospital, during 2015) and cohort WGS (89 patients included in a WGS-first prospective study in 2017). The analysis compared healthcare consumption over a 2-year period after referral for genetic testing, the diagnostic yield over a 2- and 3-year period after referral was also compiled. The mean healthcare cost per patient in cohort WGS was $2,339 lower compared to cohort CMA ($ - 2339, 95% CI - 12,238-7561; P = 0.64) including higher costs for genetic investigations ($1065, 95% CI 834-1295; P < 0.001) and lower costs for outpatient care ($ - 2330, 95% CI - 3992 to (- 669); P = 0.006). The diagnostic yield was 23% higher for cohort WGS (cohort CMA 20.1%, cohort WGS 24.7%) (0.046, 95% CI - 0.053-0.145; P = 0.36). WGS as a first-line diagnostic test for individuals with neurodevelopmental disorders is associated with statistically non-significant lower costs and higher diagnostic yield compared with CMA. This indicates that prioritizing WGS over CMA in health care decision making will yield positive expected outcomes as well as showing a need for further research.
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Trastornos del Neurodesarrollo , Humanos , Estudios Prospectivos , Estudios Retrospectivos , Análisis Costo-Beneficio , Secuenciación Completa del Genoma , Trastornos del Neurodesarrollo/diagnóstico , Trastornos del Neurodesarrollo/genéticaRESUMEN
PURPOSE: Individuals with intellectual disability (ID) and/or neurodevelopment disorders (NDDs) are currently investigated with several different approaches in clinical genetic diagnostics. METHODS: We compared the results from 3 diagnostic pipelines in patients with ID/NDD: genome sequencing (GS) first (N = 100), GS as a secondary test (N = 129), or chromosomal microarray (CMA) with or without FMR1 analysis (N = 421). RESULTS: The diagnostic yield was 35% (GS-first), 26% (GS as a secondary test), and 11% (CMA/FMR1). Notably, the age of diagnosis was delayed by 1 year when GS was performed as a secondary test and the cost per diagnosed individual was 36% lower with GS first than with CMA/FMR1. Furthermore, 91% of those with a negative result after CMA/FMR1 analysis (338 individuals) have not yet been referred for additional genetic testing and remain undiagnosed. CONCLUSION: Our findings strongly suggest that genome analysis outperforms other testing strategies and should replace traditional CMA and FMR1 analysis as a first-line genetic test in individuals with ID/NDD. GS is a sensitive, time- and cost-effective method that results in a confirmed molecular diagnosis in 35% of all referred patients.
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Discapacidad Intelectual , Trastornos del Neurodesarrollo , Niño , Humanos , Discapacidad Intelectual/diagnóstico , Discapacidad Intelectual/genética , Discapacidades del Desarrollo/genética , Pruebas Genéticas/métodos , Análisis por Micromatrices , Trastornos del Neurodesarrollo/genética , Proteína de la Discapacidad Intelectual del Síndrome del Cromosoma X Frágil/genéticaRESUMEN
OBJECTIVE: We conducted a survey-based discrete-choice experiment (DCE) to understand the test features that drive women's preferences for prenatal genomic testing, and explore variation across countries. METHODS: Five test attributes were identified as being important for decision-making through a literature review, qualitative interviews and quantitative scoring exercise. Twelve scenarios were constructed in which respondents choose between two invasive tests or no test. Women from eight countries who delivered a baby in the previous 24 months completed a DCE presenting these scenarios. Choices were modeled using conditional logit regression analysis. RESULTS: Surveys from 1239 women (Australia: n = 178; China: n = 179; Denmark: n = 88; Netherlands: n = 177; Singapore: n = 90; Sweden: n = 178; UK: n = 174; USA: n = 175) were analyzed. The key attribute affecting preferences was a test with the highest diagnostic yield (p < 0.01). Women preferred tests with short turnaround times (p < 0.01), and tests reporting variants of uncertain significance (VUS; p < 0.01) and secondary findings (SFs; p < 0.01). Several country-specific differences were identified, including time to get a result, who explains the result, and the return of VUS and SFs. CONCLUSION: Most women want maximum information from prenatal genomic tests, but our findings highlight country-based differences. Global consensus on how to return uncertain results is not necessarily realistic or desirable.
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Conducta de Elección , Prioridad del Paciente , Femenino , Pruebas Genéticas , Genómica , Humanos , Embarazo , Diagnóstico Prenatal , Encuestas y CuestionariosRESUMEN
Birt-Hogg-Dube syndrome (BHDS) (MIM: 135150) is a rare autosomal dominant disorder with variable penetrance, caused by pathogenic variants in the FLCN gene. Only a few hundreds of families have so far been described in the literature. Patients with BHDS present with three distinct symptoms: fibrofolliculomas, pneumothorax due to lung cyst formation, and increased lifetime risk of kidney tumours. The aim of the current study was to estimate the incidence of BHDS in the Swedish population and further describe the clinical manifestations and their frequency. Splice variant c.779+1G>T was the most common pathogenic variant, found in 57% of the families, suggesting this may be a founder mutation in the Swedish population. This was further investigated using haplotype analysis in 50 families that shared a common haplotype. Moreover, according to gnomAD the carrier frequency of the c.779+1G>T variant has been estimated to be 1/3265 in the Swedish population, however our data suggest that the carrier frequency in the Swedish population may be significantly higher. These findings should raise awareness among physicians of different specialties to patients presenting with fibrofolliculomas, pneumothorax and/or kidney tumours. We also stress the importance of consensus recommendations regarding diagnosis and clinical management of this, not that uncommon, syndrome.
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Síndrome de Birt-Hogg-Dubé/patología , Mutación , Proteínas Proto-Oncogénicas/genética , Proteínas Supresoras de Tumor/genética , Adulto , Síndrome de Birt-Hogg-Dubé/epidemiología , Síndrome de Birt-Hogg-Dubé/genética , Femenino , Humanos , Masculino , Linaje , Estudios Retrospectivos , Suecia/epidemiologíaRESUMEN
Prenatal DNA tests, such as chromosomal microarray analysis or exome sequencing, increase the likelihood of receiving a diagnosis when fetal structural anomalies are identified. However, some parents will receive uncertain results such as variants of uncertain significance and secondary findings. We aimed to develop a set of attributes and associated levels for a discrete-choice experiment (DCE) that will examine parents' preferences for tests that may reveal uncertain test results. A two phase mixed-methods approach was used to develop attributes for the DCE. In Phase 1, a "long list" of candidate attributes were identified via two approaches: 1) a systematic review of the literature around parental experiences of uncertainty following prenatal testing; 2) 16 semi-structured interviews with parents who had experienced uncertainty during pregnancy and 25 health professionals who return uncertain prenatal results. In Phase 2, a quantitative scoring exercise with parents prioritised the candidate attributes. Clinically appropriate levels for each attribute were then developed. A final set of five attributes and levels were identified: likelihood of getting a result, reporting of variants of uncertain significance, reporting of secondary findings, time taken to receive results, and who tells you about your result. These attributes will be used in an international DCE study to investigate preferences and differences across countries. This research will inform best practice for professionals supporting parents to manage uncertainty in the prenatal setting.
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Pruebas Genéticas , Genómica , Prioridad del Paciente , Diagnóstico Prenatal , Adulto , Femenino , Humanos , Persona de Mediana EdadRESUMEN
If a disease affects fewer than 1 in 2 000, the European Union defines it as a rare disease. Globally, about 300 million people live with a rare disease, and in Sweden about 400 000. There are approximately 7 000 different rare diseases. The clinical picture varies from a single symptom to complex patterns with multiple organs affected, often combined with cognitive and motor impairment. At least 72 % of all rare diseases are genetic and 70% have childhood onset. Many patients are undiagnosed and do not receive optimal treatment. Today, only 5% of rare diseases have an approved treatment option. With modern genetic high throughput techniques, many disease-causing mutations are identified, increasing the possibility of personalized treatment and prevention strategies, designed by the individual's genetic conditions, i.e. precision medicine.
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Medicina de Precisión , Enfermedades Raras , Humanos , Enfermedades Raras/diagnóstico , Enfermedades Raras/genética , Suecia , Secuenciación Completa del GenomaRESUMEN
BACKGROUND: We report the findings from 4437 individuals (3219 patients and 1218 relatives) who have been analyzed by whole genome sequencing (WGS) at the Genomic Medicine Center Karolinska-Rare Diseases (GMCK-RD) since mid-2015. GMCK-RD represents a long-term collaborative initiative between Karolinska University Hospital and Science for Life Laboratory to establish advanced, genomics-based diagnostics in the Stockholm healthcare setting. METHODS: Our analysis covers detection and interpretation of SNVs, INDELs, uniparental disomy, CNVs, balanced structural variants, and short tandem repeat expansions. Visualization of results for clinical interpretation is carried out in Scout-a custom-developed decision support system. Results from both singleton (84%) and trio/family (16%) analyses are reported. Variant interpretation is done by 15 expert teams at the hospital involving staff from three clinics. For patients with complex phenotypes, data is shared between the teams. RESULTS: Overall, 40% of the patients received a molecular diagnosis ranging from 19 to 54% for specific disease groups. There was heterogeneity regarding causative genes (n = 754) with some of the most common ones being COL2A1 (n = 12; skeletal dysplasia), SCN1A (n = 8; epilepsy), and TNFRSF13B (n = 4; inborn errors of immunity). Some causative variants were recurrent, including previously known founder mutations, some novel mutations, and recurrent de novo mutations. Overall, GMCK-RD has resulted in a large number of patients receiving specific molecular diagnoses. Furthermore, negative cases have been included in research studies that have resulted in the discovery of 17 published, novel disease-causing genes. To facilitate the discovery of new disease genes, GMCK-RD has joined international data sharing initiatives, including ClinVar, UDNI, Beacon, and MatchMaker Exchange. CONCLUSIONS: Clinical WGS at GMCK-RD has provided molecular diagnoses to over 1200 individuals with a broad range of rare diseases. Consolidation and spread of this clinical-academic partnership will enable large-scale national collaboration.
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Atención a la Salud , Enfermedades Raras/diagnóstico , Enfermedades Raras/genética , Secuenciación Completa del Genoma , Estudios de Cohortes , Variaciones en el Número de Copia de ADN/genética , Heterogeneidad Genética , Genómica , Secuenciación de Nucleótidos de Alto Rendimiento , Humanos , Difusión de la Información , Patrón de Herencia/genética , Repeticiones de Microsatélite/genética , Mutación/genética , Suecia , Disomía Uniparental/genéticaRESUMEN
OBJECTIVES: To conduct qualitative interviews with healthcare providers working in different countries to understand their experiences of dealing with uncertain results from prenatal chromosome microarray analysis (CMA) and exome sequencing (ES). METHODS: Semi-structured interviews with 31 healthcare providers who report or return prenatal CMA and/or ES results (clinicians, genetic counsellors and clinical scientists) in six countries with differing healthcare systems; Australia (4), Denmark (5), Netherlands (6), Singapore (4), Sweden (6) and United Kingdom (6). The topic guide explored the main sources of uncertainty and their management. RESULTS: There was variation in reporting practices both between and across countries for variants of uncertain significance, however, there was broad agreement on reporting practices for incidental findings. There was also variation in who decides what results are reported (clinical scientists or clinicians). Technical limitations and lack of knowledge (to classify variants and of prenatal phenotypes) were significant challenges, as were turnaround times and lack of guidelines. CONCLUSION: Health professionals around the globe are dealing with similar sources of uncertainty, but managing them in different ways, Continued dialogue with international colleagues on ways of managing uncertain results is important to compare and contrast the benefits and limitations of the different approaches.
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Secuenciación del Exoma/normas , Personal de Salud/psicología , Análisis por Micromatrices/normas , Incertidumbre , Adulto , Australia , Estudios Transversales , Dinamarca , Femenino , Personal de Salud/estadística & datos numéricos , Humanos , Entrevistas como Asunto/métodos , Análisis por Micromatrices/métodos , Análisis por Micromatrices/estadística & datos numéricos , Países Bajos , Embarazo , Atención Prenatal/métodos , Atención Prenatal/normas , Atención Prenatal/estadística & datos numéricos , Singapur , Suecia , Reino Unido , Secuenciación del Exoma/métodos , Secuenciación del Exoma/estadística & datos numéricosRESUMEN
PURPOSE: Postsynaptic density protein-95 (PSD-95), encoded by DLG4, regulates excitatory synaptic function in the brain. Here we present the clinical and genetic features of 53 patients (42 previously unpublished) with DLG4 variants. METHODS: The clinical and genetic information were collected through GeneMatcher collaboration. All the individuals were investigated by local clinicians and the gene variants were identified by clinical exome/genome sequencing. RESULTS: The clinical picture was predominated by early onset global developmental delay, intellectual disability, autism spectrum disorder, and attention deficit-hyperactivity disorder, all of which point to a brain disorder. Marfanoid habitus, which was previously suggested to be a characteristic feature of DLG4-related phenotypes, was found in only nine individuals and despite some overlapping features, a distinct facial dysmorphism could not be established. Of the 45 different DLG4 variants, 39 were predicted to lead to loss of protein function and the majority occurred de novo (four with unknown origin). The six missense variants identified were suggested to lead to structural or functional changes by protein modeling studies. CONCLUSION: The present study shows that clinical manifestations associated with DLG4 overlap with those found in other neurodevelopmental disorders of synaptic dysfunction; thus, we designate this group of disorders as DLG4-related synaptopathy.
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Trastorno del Espectro Autista , Encefalopatías , Discapacidad Intelectual , Trastornos del Neurodesarrollo , Trastorno del Espectro Autista/diagnóstico , Trastorno del Espectro Autista/genética , Encéfalo , Homólogo 4 de la Proteína Discs Large/genética , Humanos , Trastornos del Neurodesarrollo/diagnóstico , Trastornos del Neurodesarrollo/genética , FenotipoRESUMEN
Backgrounds and Purpose- Although new methods for genetic analyses are rapidly evolving, there are currently knowledge gaps in how to detect Mendelian forms of stroke. Methods- We performed whole-exome sequencing in 22 probands, under 56 years at their first ischemic stroke episode, from multi-incident stroke families. With the use of a comprehensive stroke-gene panel, we searched for variants in stroke-related genes. The probands' clinical stroke subtype was related to clinical characteristics previously associated with pathogenic variants in these genes. Relatives were genotyped in 7 families to evaluate stroke-gene variants of unknown significance. In 2 larger families with embolic stroke of unknown source, whole-exome sequencing was performed in additional members to examine the possibility of identifying new stroke genes. Results- Six of 22 probands carried pathogenic or possibly pathogenic variants in genes reported to be associated with their stroke subtype. A known pathogenic variant in NOTCH3 and a possibly pathogenic variant in ACAD9 gene were identified. A novel JAK2:c.3188G>A (p.Arg1063His) mutation was seen in a proband with embolic stroke of undetermined source and prothrombotic status. However, penetrance in the family was incomplete. COL4A2:c.3368A>G (p.Glu1123Gly) was detected in 2 probands but did not cosegregate with the disease in their families. Whole-exome sequencing in multiple members of 2 pedigrees with embolic stroke of undetermined source revealed possibly pathogenic variants in genes not previously associated with stroke, GPR142:c.148C>G (p.Leu50Val), and PTPRN2:c.2416A>G (p.Ile806Val); LRRC1 c.808A>G (p.Ile270Val), SLC7A10c.1294dupG (p.Val432fs), IKBKB: c.1070C>T (p.Ala357Val), and OXGR1 c.392G>A (p.Arg131His), respectively. Conclusions- Screening with whole-exome sequencing using a comprehensive stroke-gene panel may identify rare monogenic forms of stroke, but careful evaluation of clinical characteristics and potential pathogenicity of novel variants remain important. In our study, the majority of individuals with familial aggregation of stroke lacked any identified genetic causes.
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Isquemia Encefálica/diagnóstico , Isquemia Encefálica/genética , Secuenciación del Exoma/métodos , Accidente Cerebrovascular/diagnóstico , Accidente Cerebrovascular/genética , Adulto , Anciano , Análisis por Conglomerados , Femenino , Humanos , Masculino , Persona de Mediana Edad , Linaje , Estudios ProspectivosRESUMEN
BACKGROUND: Since different types of genetic variants, from single nucleotide variants (SNVs) to large chromosomal rearrangements, underlie intellectual disability, we evaluated the use of whole-genome sequencing (WGS) rather than chromosomal microarray analysis (CMA) as a first-line genetic diagnostic test. METHODS: We analyzed three cohorts with short-read WGS: (i) a retrospective cohort with validated copy number variants (CNVs) (cohort 1, n = 68), (ii) individuals referred for monogenic multi-gene panels (cohort 2, n = 156), and (iii) 100 prospective, consecutive cases referred to our center for CMA (cohort 3). Bioinformatic tools developed include FindSV, SVDB, Rhocall, Rhoviz, and vcf2cytosure. RESULTS: First, we validated our structural variant (SV)-calling pipeline on cohort 1, consisting of three trisomies and 79 deletions and duplications with a median size of 850 kb (min 500 bp, max 155 Mb). All variants were detected. Second, we utilized the same pipeline in cohort 2 and analyzed with monogenic WGS panels, increasing the diagnostic yield to 8%. Next, cohort 3 was analyzed by both CMA and WGS. The WGS data was processed for large (> 10 kb) SVs genome-wide and for exonic SVs and SNVs in a panel of 887 genes linked to intellectual disability as well as genes matched to patient-specific Human Phenotype Ontology (HPO) phenotypes. This yielded a total of 25 pathogenic variants (SNVs or SVs), of which 12 were detected by CMA as well. We also applied short tandem repeat (STR) expansion detection and discovered one pathologic expansion in ATXN7. Finally, a case of Prader-Willi syndrome with uniparental disomy (UPD) was validated in the WGS data. Important positional information was obtained in all cohorts. Remarkably, 7% of the analyzed cases harbored complex structural variants, as exemplified by a ring chromosome and two duplications found to be an insertional translocation and part of a cryptic unbalanced translocation, respectively. CONCLUSION: The overall diagnostic rate of 27% was more than doubled compared to clinical microarray (12%). Using WGS, we detected a wide range of SVs with high accuracy. Since the WGS data also allowed for analysis of SNVs, UPD, and STRs, it represents a powerful comprehensive genetic test in a clinical diagnostic laboratory setting.
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Análisis Citogenético/métodos , Marcadores Genéticos , Genoma Humano , Discapacidad Intelectual/diagnóstico , Discapacidad Intelectual/genética , Polimorfismo de Nucleótido Simple , Secuenciación Completa del Genoma/métodos , Niño , Aberraciones Cromosómicas , Variaciones en el Número de Copia de ADN , Pruebas Diagnósticas de Rutina , Femenino , Humanos , Masculino , Proyectos Piloto , Estudios Prospectivos , Estudios RetrospectivosRESUMEN
OBJECTIVE: To determine the frequency of mutations known to cause autosomal dominant Parkinson disease (PD) in a series with more than 10% of Sweden's estimated number of PD patients. METHODS: The Swedish Parkinson Disease Genetics Network was formed as a national multicenter consortium of clinical researchers who together have access to DNA from a total of 2,206 PD patients; 85.4% were from population-based studies. Samples were analyzed centrally for known pathogenic mutations in SNCA (duplications/triplications, p.Ala30Pro, p.Ala53Thr) and LRRK2 (p.Asn1437His, p.Arg1441His, p.Tyr1699Cys, p.Gly2019Ser, p.Ile2020Thr). We compared the frequency of these mutations in Swedish patients with published PD series and the gnomAD database. RESULTS: A family history of PD in first- and/or second-degree relatives was reported by 21.6% of participants. Twelve patients (0.54%) carried LRRK2 p.(Gly2019Ser) mutations, one patient (0.045%) an SNCA duplication. The frequency of LRRK2 p.(Gly2019Ser) carriers was 0.11% in a matched Swedish control cohort and a similar 0.098% in total gnomAD, but there was a marked difference between ethnicities in gnomAD, with 42-fold higher frequency among Ashkenazi Jews than all others combined. CONCLUSIONS: In relative terms, the LRRK2 p.(Gly2019Ser) variant is the most frequent mutation among Swedish or international PD patients, and in gnomAD. SNCA duplications were the second most common of the mutations examined. In absolute terms, however, these known pathogenic variants in dominant PD genes are generally very rare and can only explain a minute fraction of familial aggregation of PD. Additional genetic and environmental mechanisms may explain the frequent co-occurrence of PD in close relatives.
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Predisposición Genética a la Enfermedad/genética , Enfermedad de Parkinson/genética , Variaciones en el Número de Copia de ADN , Bases de Datos Genéticas , Humanos , Judíos/genética , Proteína 2 Quinasa Serina-Treonina Rica en Repeticiones de Leucina/genética , Mutación , Enfermedad de Parkinson/etnología , Suecia/etnología , alfa-Sinucleína/genéticaRESUMEN
Psychiatric genetic counseling (PGC) is gradually developing globally, with countries in various stages of development. In some, PGC is established as a service or as part of research projects while in others, it is just emerging as a concept. In this article, we describe the current global landscape of this genetic counseling specialty and this field's professional development. Drawing on information provided by expert representatives from 16 countries, we highlight the following: (a) current understanding of PGC; (b) availability of services for patients; (c) availability of training; (d) healthcare system disparities and cultural differences impacting practice; and (e) anticipated challenges going forward.
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Asesoramiento Genético/psicología , Asesoramiento Genético/tendencias , Trastornos Mentales/genética , Humanos , Trastornos Mentales/psicologíaRESUMEN
Extensive analyses of known monogenic causes of stroke by whole-exome/genome sequencing are technically possible today. We here aimed to compile a comprehensive panel of genes associated with monogenic causes of stroke for use in clinical and research situations. We systematically searched the publically available database Online Mendelian Inheritance in Man, and validated the entries against original peer-reviewed publications in PubMed. First, we selected known pathogenic or putatively pathogenic stroke genes reported in at least one person with stroke, and classified the stroke phenotype for each gene into eight subgroups: (1) large artery atherosclerotic, (2) large artery non-atherosclerotic (tortuosity, dolichoectasia, aneurysm, non-atherosclerotic dissection, occlusion), (3) cerebral small-vessel diseases, (4) cardioembolic (arrhythmia, heart defect, cardiomyopathy), (5) coagulation dysfunctions (venous thrombosis, arterial thrombosis, bleeding tendency), (6) intracerebral hemorrhage, (7) vascular malformations (cavernoma, arteriovenous malformations), and (8) metabolism disorders. Second, we selected other genes that may plausibly cause stroke through diseases related to stroke, but without any documented stroke patient description. A third section comprised SNPs associated with stroke in genome-wide association studies (GWAS). We identified in total 214 genes: 120 associated with stroke, 62 associated with diseases that may cause stroke, and 32 stroke-related genes from recent GWAS. We describe these 214 genes and the clinical stroke subtype(s) associated with each of them. The resulting gene panel can be used to interpret exome sequencing results regarding monogenic stroke. Based on the panel's clinical phenotype description, the pathogenicity of novel variants in these genes may be evaluated in specific situations.
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Secuenciación del Exoma , Polimorfismo de Nucleótido Simple , Accidente Cerebrovascular/genética , Bases de Datos Genéticas , Estudio de Asociación del Genoma Completo , HumanosRESUMEN
BACKGROUND: Mitochondrial diseases due to defective respiratory chain complex III (CIII) are relatively uncommon. The assembly of the eleven-subunit CIII is completed by the insertion of the Rieske iron-sulfur protein, a process for which BCS1L protein is indispensable. Mutations in the BCS1L gene constitute the most common diagnosed cause of CIII deficiency, and the phenotypic spectrum arising from mutations in this gene is wide. RESULTS: A case of CIII deficiency was investigated in depth to assess respiratory chain function and assembly, and brain, skeletal muscle and liver histology. Exome sequencing was performed to search for the causative mutation(s). The patient's platelets and muscle mitochondria showed respiration defects and defective assembly of CIII was detected in fibroblast mitochondria. The patient was compound heterozygous for two novel mutations in BCS1L, c.306A > T and c.399delA. In the cerebral cortex a specific pattern of astrogliosis and widespread loss of microglia was observed. Further analysis showed loss of Kupffer cells in the liver. These changes were not found in infants suffering from GRACILE syndrome, the most severe BCS1L-related disorder causing early postnatal mortality, but were partially corroborated in a knock-in mouse model of BCS1L deficiency. CONCLUSIONS: We describe two novel compound heterozygous mutations in BCS1L causing CIII deficiency. The pathogenicity of one of the mutations was unexpected and points to the importance of combining next generation sequencing with a biochemical approach when investigating these patients. We further show novel manifestations in brain, skeletal muscle and liver, including abnormality in specialized resident macrophages (microglia and Kupffer cells). These novel phenotypes forward our understanding of CIII deficiencies caused by BCS1L mutations.
Asunto(s)
Acidosis Láctica/genética , Colestasis/genética , Retardo del Crecimiento Fetal/genética , Hemosiderosis/genética , Errores Innatos del Metabolismo/genética , Enfermedades Mitocondriales/congénito , Aminoacidurias Renales/genética , Animales , Transporte de Electrón/fisiología , Complejo III de Transporte de Electrones/genética , Flavoproteínas Transportadoras de Electrones/genética , Secuenciación de Nucleótidos de Alto Rendimiento , Humanos , Ratones , Enfermedades Mitocondriales/genética , Encefalomiopatías Mitocondriales/genética , Mutación/genéticaRESUMEN
OBJECTIVE: Women with Lynch syndrome (LS) have up to a 60% lifetime risk of endometrial cancer (EC) and up to a 24% risk of ovarian cancer (OC). Gynecological surveillance is recommended, but the benefit and how it should be performed remain unclear. The purpose of this study was to assess diagnostic modalities for gynecological screening of LS patients in Sweden and clinical outcome. METHODS: A retrospective nationwide study of 170 women with molecularly confirmed LS. Data including gynecological LS screening history, biopsy results (if any), genetic records, number of screening visits, results from screening including transvaginal ultrasound (TVUS), endometrial biopsy (EB), blood test for tumor marker cancer antigen (CA) 125, prophylactic surgery including age at procedure, and setting from which screening data were obtained from medical records. RESULTS: A total of 117 women were eligible for gynecological screening and of these, 86 patients attended screening visits. Of these, 41 underwent prophylactic hysterectomy and/or bilateral salpingo-oophorectomy. Two patients (4.9%) were diagnosed with EC and two (4.9%) with precancerous lesions in conjunction with prophylactic surgery. Total incidence of gynecological cancer in the surveillance group (45 women) was 20% EC, 4% OC. Five patients had endometrial cancer or complex hyperplasia with atypia (n=2) detected by endometrial biopsy. Four additional cases were detected due to interval bleeding. Both cases of ovarian cancer were detected by transvaginal ultrasound in patients with ovarian cysts under surveillance. The youngest woman with endometrial cancer was diagnosed at 35 years of age, before she was aware of her diagnosis of Lynch syndrome. CONCLUSIONS: Gynecological surveillance of women with Lynch syndrome may lead to earlier detection of precancerous lesions, which might have some impact on the morbidity from endometrial cancer although further studies are needed to prove this. Prophylactic hysterectomy with or without bilateral salpingo-oophorectomy reduces the cancer incidence. A practical approach to surveillance in Lynch syndrome women would be to offer annual surveillance beginning at age 30 years including probably both TVUS and EB in order to increase diagnostic yield with prospective data registry for follow-up studies. Prophylactic surgery could be performed at a suitable age after childbearing to obtain a balance between reducing the risk of cancer and minimizing long-term complications from premature menopause.