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Developmental delay and intellectual disability (DD and ID) are heterogeneous phenotypes that arise in many rare monogenic disorders. Because of this rarity, developing cohorts with enough individuals to robustly identify disease-associated genes is challenging. Social-media platforms that facilitate data sharing among sequencing labs can help to address this challenge. Through one such tool, GeneMatcher, we identified nine DD- and/or ID-affected probands with a rare, heterozygous variant in the gene encoding the serine/threonine-protein kinase BRSK2. All probands have a speech delay, and most present with intellectual disability, motor delay, behavioral issues, and autism. Six of the nine variants are predicted to result in loss of function, and computational modeling predicts that the remaining three missense variants are damaging to BRSK2 structure and function. All nine variants are absent from large variant databases, and BRSK2 is, in general, relatively intolerant to protein-altering variation among humans. In all six probands for whom parents were available, the mutations were found to have arisen de novo. Five of these de novo variants were from cohorts with at least 400 sequenced probands; collectively, the cohorts span 3,429 probands, and the observed rate of de novo variation in these cohorts is significantly higher than the estimated background-mutation rate (p = 2.46 × 10-6). We also find that exome sequencing provides lower coverage and appears less sensitive to rare variation in BRSK2 than does genome sequencing; this fact most likely reduces BRSK2's visibility in many clinical and research sequencing efforts. Altogether, our results implicate damaging variation in BRSK2 as a source of neurodevelopmental disease.
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Discapacidades del Desarrollo/genética , Eliminación de Gen , Discapacidad Intelectual/genética , Trastornos del Neurodesarrollo/genética , Proteínas Serina-Treonina Quinasas/genética , Adolescente , Trastorno Autístico/genética , Niño , Trastornos de la Conducta Infantil/genética , Preescolar , Exoma , Femenino , Predisposición Genética a la Enfermedad , Variación Genética , Heterocigoto , Humanos , Masculino , Trastornos de la Destreza Motora/genética , Mutación , Fenotipo , Secuenciación del Exoma , Adulto JovenRESUMEN
PURPOSE: SouthSeq is a translational research study that undertook genome sequencing (GS) for infants with symptoms suggestive of a genetic disorder. Recruitment targeted racial/ethnic minorities and rural, medically underserved areas in the Southeastern United States, which are historically underrepresented in genomic medicine research. METHODS: GS and analysis were performed for 367 infants to detect disease-causal variation concurrent with standard of care evaluation and testing. RESULTS: Definitive diagnostic (DD) or likely diagnostic (LD) genetic findings were identified in 30% of infants, and 14% of infants harbored an uncertain result. Only 43% of DD/LD findings were identified via concurrent clinical genetic testing, suggesting that GS testing is better for obtaining early genetic diagnosis. We also identified phenotypes that correlate with the likelihood of receiving a DD/LD finding, such as craniofacial, ophthalmologic, auditory, skin, and hair abnormalities. We did not observe any differences in diagnostic rates between racial/ethnic groups. CONCLUSION: We describe one of the largest-to-date GS cohorts of ill infants, enriched for African American and rural patients. Our results show the utility of GS because it provides early-in-life detection of clinically relevant genetic variations not detected by current clinical genetic testing, particularly for infants exhibiting certain phenotypic features.
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Pruebas Diagnósticas de Rutina , Pruebas Genéticas , Secuencia de Bases , Mapeo Cromosómico , Pruebas Genéticas/métodos , Genómica , HumanosRESUMEN
PURPOSE: To evaluate the effectiveness and specificity of population-based genomic screening in Alabama. METHODS: The Alabama Genomic Health Initiative (AGHI) has enrolled and evaluated 5369 participants for the presence of pathogenic/likely pathogenic (P/LP) variants using the Illumina Global Screening Array (GSA), with validation of all P/LP variants via Sanger sequencing in a CLIA-certified laboratory before return of results. RESULTS: Among 131 variants identified by the GSA that were evaluated by Sanger sequencing, 67 (51%) were false positives (FP). For 39 of the 67 FP variants, a benign/likely benign variant was present at or near the targeted P/LP variant. Variants detected within African American individuals were significantly enriched for FPs, likely due to a higher rate of nontargeted alternative alleles close to array-targeted P/LP variants. CONCLUSION: In AGHI, we have implemented an array-based process to screen for highly penetrant genetic variants in actionable disease genes. We demonstrate the need for clinical validation of array-identified variants in direct-to-consumer or population testing, especially for diverse populations.
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Pruebas Genéticas , Genómica , Alabama , Variación Genética , Secuenciación de Nucleótidos de Alto Rendimiento , HumanosRESUMEN
PURPOSE: Clinically relevant secondary variants were identified in parents enrolled with a child with developmental delay and intellectual disability. METHODS: Exome/genome sequencing and analysis of 789 "unaffected" parents was performed. RESULTS: Pathogenic/likely pathogenic variants were identified in 21 genes within 25 individuals (3.2%), with 11 (1.4%) participants harboring variation in a gene defined as clinically actionable by the American College of Medical Genetics and Genomics. These 25 individuals self-reported either relevant clinical diagnoses (5); relevant family history or symptoms (13); or no relevant family history, symptoms, or clinical diagnoses (7). A limited carrier screen was performed yielding 15 variants in 48 (6.1%) parents. Parents were also analyzed as mate pairs (n = 365) to identify cases in which both parents were carriers for the same recessive disease, yielding three such cases (0.8%), two of which had children with the relevant recessive disease. Four participants had two findings (one carrier and one noncarrier variant). In total, 71 of the 789 enrolled parents (9.0%) received secondary findings. CONCLUSION: We provide an overview of the rates and types of clinically relevant secondary findings, which may be useful in the design and implementation of research and clinical sequencing efforts to identify such findings.
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Secuenciación del Exoma , Exoma/genética , Enfermedades Genéticas Congénitas/genética , Pruebas Genéticas , Adulto , Mapeo Cromosómico , Femenino , Tamización de Portadores Genéticos , Enfermedades Genéticas Congénitas/clasificación , Enfermedades Genéticas Congénitas/fisiopatología , Variación Genética , Genoma Humano/genética , Humanos , Masculino , Persona de Mediana Edad , Mutación , Padres , Secuenciación Completa del GenomaRESUMEN
PURPOSE: As massively parallel sequencing is increasingly being used for clinical decision making, it has become critical to understand parameters that affect sequencing quality and to establish methods for measuring and reporting clinical sequencing standards. In this report, we propose a definition for reduced coverage regions and describe a set of standards for variant calling in clinical sequencing applications. METHODS: To enable sequencing centers to assess the regions of poor sequencing quality in their own data, we optimized and used a tool (ExCID) to identify reduced coverage loci within genes or regions of particular interest. We used this framework to examine sequencing data from 500 patients generated in 10 projects at sequencing centers in the National Human Genome Research Institute/National Cancer Institute Clinical Sequencing Exploratory Research Consortium. RESULTS: This approach identified reduced coverage regions in clinically relevant genes, including known clinically relevant loci that were uniquely missed at individual centers, in multiple centers, and in all centers. CONCLUSION: This report provides a process road map for clinical sequencing centers looking to perform similar analyses on their data.
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Secuenciación del Exoma/métodos , Análisis de Secuencia de ADN/métodos , Secuenciación Completa del Genoma/métodos , Secuencia de Bases , Mapeo Cromosómico , Exoma , Genoma Humano , Secuenciación de Nucleótidos de Alto Rendimiento/métodos , Humanos , Análisis de Secuencia de ADN/normas , Programas InformáticosRESUMEN
BACKGROUND: It is critical to understand the wide-ranging clinical and non-clinical effects of genome sequencing (GS) for parents in the NICU context. We assessed parents' experiences with GS as a first-line diagnostic tool for infants with suspected genetic conditions in the NICU. METHODS: Parents of newborns (N = 62) suspected of having a genetic condition were recruited across five hospitals in the southeast United States as part of the SouthSeq study. Semi-structured interviews (N = 78) were conducted after parents received their child's sequencing result (positive, negative, or variants of unknown significance). Thematic analysis was performed on all interviews. RESULTS: Key themes included that (1) GS in infancy is important for reproductive decision making, preparing for the child's future care, ending the diagnostic odyssey, and sharing results with care providers; (2) the timing of disclosure was acceptable for most parents, although many reported the NICU environment was overwhelming; and (3) parents deny that receiving GS results during infancy exacerbated parent-infant bonding, and reported variable impact on their feelings of guilt. CONCLUSION: Parents reported that GS during the neonatal period was useful because it provided a "backbone" for their child's care. Parents did not consistently endorse negative impacts like interference with parent-infant bonding.
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Background: The desire of parents to obtain a genetic diagnosis for their child with intellectual disability and associated symptoms has long been framed as a diagnostic odyssey, an arduous and sometimes perilous journey focused on the goal of identifying a cause for the child's condition.Methods: Semi-structured interviews (N = 60) were conducted with parents of children (N = 59, aged 2-24 years) with intellectual disability and/or developmental delay (IDD) who underwent genome sequencing at a single pediatric multispecialty clinic. Interviews were conducted after parents received their child's sequencing result (positive findings, negative findings, or variants of unknown significance). Thematic analysis was performed on all interviews.Results: Parents reported that obtaining a genetic diagnosis was one important step in their overall goal of helping their child live their best life possible life. They intended to use the result as a tool to help their child by seeking the correct school placement and obtaining benefits and therapeutic services.Conclusions: For the parents of children with IDD, the search for a genetic diagnosis is best conceptualized as a part of parents' ongoing efforts to leverage various diagnoses to obtain educational and therapeutic services for their children. Cleaving parents' search for a genetic diagnosis from these broader efforts obscures the value that some parents place on a sequencing result in finding and tailoring therapies and services beyond the clinic. Interviews with parents reveal, therefore, that genomic sequencing is best understood as one important stage of an ongoing therapeutic odyssey that largely takes place outside the clinic. Findings suggest the need to expand translational research efforts to contextualize a genetic diagnosis within parents' broader efforts to obtain educational and therapeutic services outside clinical contexts.
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Motivación , Padres , Secuencia de Bases , Niño , Familia , Genómica , HumanosRESUMEN
Exome and genome sequencing have proven to be effective tools for the diagnosis of neurodevelopmental disorders (NDDs), but large fractions of NDDs cannot be attributed to currently detectable genetic variation. This is likely, at least in part, a result of the fact that many genetic variants are difficult or impossible to detect through typical short-read sequencing approaches. Here, we describe a genomic analysis using Pacific Biosciences circular consensus sequencing (CCS) reads, which are both long (>10 kb) and accurate (>99% bp accuracy). We used CCS on six proband-parent trios with NDDs that were unexplained despite extensive testing, including genome sequencing with short reads. We identified variants and created de novo assemblies in each trio, with global metrics indicating these datasets are more accurate and comprehensive than those provided by short-read data. In one proband, we identified a likely pathogenic (LP), de novo L1-mediated insertion in CDKL5 that results in duplication of exon 3, leading to a frameshift. In a second proband, we identified multiple large de novo structural variants, including insertion-translocations affecting DGKB and MLLT3, which we show disrupt MLLT3 transcript levels. We consider this extensive structural variation likely pathogenic. The breadth and quality of variant detection, coupled to finding variants of clinical and research interest in two of six probands with unexplained NDDs, support the hypothesis that long-read genome sequencing can substantially improve rare disease genetic discovery rates.
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We assessed the results of genome sequencing for early-onset dementia. Participants were selected from a memory disorders clinic. Genome sequencing was performed along with C9orf72 repeat expansion testing. All returned sequencing results were Sanger-validated. Prior clinical diagnoses included Alzheimer's disease, frontotemporal dementia, and unspecified dementia. The mean age of onset was 54 (41-76). Fifty percent of patients had a strong family history, 37.5% had some, and 12.5% had no known family history. Nine of 32 patients (28%) had a variant defined as pathogenic or likely pathogenic (P/LP) by American College of Medical Genetics and Genomics standards, including variants in APP, C9orf72, CSF1R, and MAPT Nine patients (including three with P/LP variants) harbored established risk alleles with moderate penetrance (odds ratios of â¼2-5) in ABCA7, AKAP9, GBA, PLD3, SORL1, and TREM2 All six patients harboring these moderate penetrance variants but not P/LP variants also had one or two APOE ε4 alleles. One patient had two APOE ε4 alleles with no other established contributors. In total, 16 patients (50%) harbored one or more genetic variants likely to explain symptoms. We identified variants of uncertain significance (VUSs) in ABI3, ADAM10, ARSA, GRID2IP, MME, NOTCH3, PLCD1, PSEN1, TM2D3, TNK1, TTC3, and VPS13C, also often along with other variants. In summary, genome sequencing for early-onset dementia frequently identified multiple established or possible contributory alleles. These observations add support for an oligogenic model for early-onset dementia.
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Enfermedad de Alzheimer/genética , Demencia/genética , Anciano , Alelos , Apolipoproteína E4/genética , Secuencia de Bases , Proteína C9orf72/genética , Mapeo Cromosómico , Femenino , Estudios de Asociación Genética , Predisposición Genética a la Enfermedad , Variación Genética , Estudio de Asociación del Genoma Completo , Humanos , Masculino , Persona de Mediana Edad , Oportunidad Relativa , Penetrancia , Factores de Riesgo , Secuenciación Completa del Genoma/métodosRESUMEN
BACKGROUND: Developmental disabilities have diverse genetic causes that must be identified to facilitate precise diagnoses. We describe genomic data from 371 affected individuals, 309 of which were sequenced as proband-parent trios. METHODS: Whole-exome sequences (WES) were generated for 365 individuals (127 affected) and whole-genome sequences (WGS) were generated for 612 individuals (244 affected). RESULTS: Pathogenic or likely pathogenic variants were found in 100 individuals (27%), with variants of uncertain significance in an additional 42 (11.3%). We found that a family history of neurological disease, especially the presence of an affected first-degree relative, reduces the pathogenic/likely pathogenic variant identification rate, reflecting both the disease relevance and ease of interpretation of de novo variants. We also found that improvements to genetic knowledge facilitated interpretation changes in many cases. Through systematic reanalyses, we have thus far reclassified 15 variants, with 11.3% of families who initially were found to harbor a VUS and 4.7% of families with a negative result eventually found to harbor a pathogenic or likely pathogenic variant. To further such progress, the data described here are being shared through ClinVar, GeneMatcher, and dbGaP. CONCLUSIONS: Our data strongly support the value of large-scale sequencing, especially WGS within proband-parent trios, as both an effective first-choice diagnostic tool and means to advance clinical and research progress related to pediatric neurological disease.
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Variaciones en el Número de Copia de ADN , Discapacidades del Desarrollo/genética , Genómica/métodos , Discapacidad Intelectual/genética , Mutación , Análisis de Secuencia de ADN/métodos , Adolescente , Adulto , Niño , Preescolar , Discapacidades del Desarrollo/diagnóstico , Exoma , Femenino , Humanos , Lactante , Discapacidad Intelectual/diagnóstico , Masculino , Adulto JovenRESUMEN
In the U.S. and Australia, agriculture is consistently ranked as one of the most hazardous industries. The cost of injuries and deaths on Australian farms is significant, estimated to be between AU$0.5 billion and AU$1.2 billion per year. Death and injury in agriculture also place a significant financial and social burden on the family and friends of the injured, the community, and the health system. This article proposes that if farmers were to employ coaching in their businesses, they would benefit from advances in safety practices, resulting in associated improvements in overall farm productivity and a reduction in injury costs to the wider community. A coaching model is presented to demonstrate what an effective coaching process would need to include. An agenda for future research areas is also provided.
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Agricultura , Salud Laboral , Seguridad , Agricultura/economía , Agricultura/normas , Australia , Comercio , Salud Laboral/economía , Salud Laboral/normas , Seguridad/economía , Seguridad/normasRESUMEN
Gender is a concept that is frequently discussed in the literature on stress, coping and illness. Research has reported that women are more vulnerable than men are to stressful events and use different strategies to cope with them. Furthermore, it is often asserted that these gender-based differences in coping may partially explain the differential impact of stressful events on men and women. Unfortunately, much of this research has equated gender with sex and failed to contextualise the experience of illness and coping. This paper presents a qualitative analysis of the role of gender and coping among parents of children with high functioning autism or Asperger's syndrome in an Australian sample. It attempts to analyse the different meanings of the disability for mothers and fathers and describes the various strategies that parents use to cope with their child's disability.