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Inherited biallelic pathogenic variants (PVs) in BRCA2 cause Fanconi Anemia complementation group D1 (FA-D1), a severe pediatric bone marrow failure and high-risk cancer syndrome. We identified biallelic BRCA2 PVs in a young adult with multiple basal cell carcinomas, adult-onset colorectal cancer and small cell neuroendocrine carcinoma, without bone marrow failure. No PVs were identified in any other known cancer susceptibility gene, and there was no evidence of reversion mosaicism. The proband's deceased sister had a classic FA-D1 presentation and was shown to carry the same biallelic BRCA2 PVs. A lymphoblastoid cell line derived from the proband demonstrated hypersensitivity to DNA damaging agents, and bone marrow showed aberrant RAD51 staining. Family expansion demonstrated the presence of BRCA2 related cancers in heterozygous family members. Our data highlight the striking phenotypic differences which can be observed within FA-D1 families and expands the clinical spectrum of FA-D1 to include adult presentation with a constellation of solid tumors not previously thought of as characteristic of Fanconi Anemia. Early recognition of this syndrome in a family could prevent further morbidity and mortality by implementation of hereditary breast and ovarian cancer screening and treatment strategies for heterozygous family members.
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Anemia de Fanconi , Neoplasias , Humanos , Proteína BRCA2/genética , Anemia de Fanconi/diagnóstico , Anemia de Fanconi/genética , Irmãos , Adulto JovemRESUMO
Li-Fraumeni syndrome (LFS) is a rare hereditary cancer syndrome in which individuals have a significantly increased risk of developing multiple cancers throughout the life span. An LFS diagnosis may shift the individual's sense of self and tolerance of cancer risk as they engage in cancer screening and cancer prevention activities. This study examined the impact of family identity on health decision making, communication, and role function. Forty-five families completed one or more interviews during an annual, protocol-specific cancer screening study. An interdisciplinary team analyzed 66 interviews using interpretive description and modified grounding theory. Thematically, identity emerged as an evolving construct regarding self and/or family, embedded in historical and ongoing experiences with LFS. Notions of individual and shared family identities guided decision making related to healthcare and influenced interpersonal communication and role function between supportive networks and families. Alignment between individual, family, and generational identities may shape engagement in genetic testing, risk management, and family life. Medical teams that are unequipped to address the psychosocial challenges that LFS populations face may include mental health professionals on interprofessional care teams to navigate risk management and consequential familial conflict.
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Síndrome de Li-Fraumeni , Detecção Precoce de Câncer , Pessoal de Saúde , Humanos , Síndrome de Li-Fraumeni/genética , Programas de RastreamentoRESUMO
The original article [1] was initially published with the following list of authors: Allison Werner-Lin, Shana L. Merrill, and Amanda C. Brandt. This author list is now corrected as follows: Allison Werner-Lin, Shana L. Merrill, Amanda C. Brandt, Rachel E. Barnett, & Ellen T. Matloff.
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Families often express difficulty to their providers and request guidance regarding the task of communicating with children about potential adult-onset inherited cancer risks. This disclosure is often complicated by the parent's ongoing adjustment to their mutation status, guilt at potential transmission of the mutation to the child, concern over inciting distress in children, and the varied capacities of children in the home to understand genetic information. Providers often do not have adequate resources to support or facilitate disclosure of genetic test results to children. Optimally, communication about inherited cancer risk is an open, ongoing process within the family. We recommend that parents tailor conversations to the child's developmental, cognitive, emotional, and behavioral abilities to support comprehension. Based on well-established theories of child development, empirical research on family communication of hereditary cancer risk, and clinical counseling experience, we offer recommendations for parental disclosure of genetic risk to children, case examples with critical discussion of relevant topics, common child questions with sample scripted responses, and additional printed and online resources.
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Predisposição Genética para Doença/psicologia , Neoplasias/psicologia , Relações Pais-Filho , Pais/psicologia , Adulto , Criança , Revelação , Feminino , Testes Genéticos/estatística & dados numéricos , Humanos , Masculino , Neoplasias/diagnóstico , Neoplasias/prevenção & controle , Fatores de Risco , Revelação da VerdadeRESUMO
We report a broader than previously appreciated clinical spectrum for hereditary sensory and autonomic neuropathy type 1E (HSAN1E) and a potential pathogenic mechanism for DNA methyltransferase (DNMT1) mutations. The clinical presentations and genetic characteristics of nine newly identified HSAN1E kinships (45 affected subjects) were investigated. Five novel mutations of DNMT1 were discovered; p.C353F, p.T481P, p.P491L, p.Y524D and p.I531N, all within the target-sequence domain, and two mutations (p.T481P, p.P491L) arising de novo. Recently, HSAN1E has been suggested as an allelic disorder of autosomal dominant cerebellar ataxia, deafness and narcolepsy. Our results indicate that all the mutations causal for HSAN1E are located in the middle part or N-terminus end of the TS domain, whereas all the mutations causal for autosomal dominant cerebellar ataxia, deafness and narcolepsy are located in the C-terminus end of the TS domain. The impact of the seven causal mutations in this cohort was studied by cellular localization experiments. The binding efficiency of the mutant DNMT proteins at the replication foci and heterochromatin were evaluated. Phenotypic characterizations included electromyography, brain magnetic resonance and nuclear imaging, electroencephalography, sural nerve biopsies, sleep evaluation and neuropsychometric testing. The average survival of HSAN1E was 53.6 years. [standard deviation = 7.7, range 43-75 years], and mean onset age was 37.7 years. (standard deviation = 8.6, range 18-51 years). Expanded phenotypes include myoclonic seizures, auditory or visual hallucinations, and renal failure. Hypersomnia, rapid eye movement sleep disorder and/or narcolepsy were identified in 11 subjects. Global brain atrophy was found in 12 of 14 who had brain MRI. EEGs showed low frequency (delta waves) frontal-predominant abnormality in five of six patients. Marked variability in cognitive deficits was observed, but the majority of patients (89%) developed significant cognitive deficit by the age of 45 years. Cognitive function decline often started with personality changes and psychiatric manifestations. A triad of hearing loss, sensory neuropathy and cognitive decline remains as the stereotypic presentation of HSAN1E. Moreover, we show that mutant DNMT1 proteins translocate to the cytoplasm and are prone to form aggresomes while losing their binding ability to heterochromatin during the G2 cell cycle. Our results suggest mutations in DNMT1 result in imbalanced protein homeostasis through aggresome-induced autophagy. This mechanism may explain why mutations in the sole DNA maintenance methyltransferase lead to selective central and peripheral neurodegeneration.
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DNA (Citosina-5-)-Metiltransferases/genética , Neuropatias Hereditárias Sensoriais e Autônomas/diagnóstico , Neuropatias Hereditárias Sensoriais e Autônomas/genética , Mutação/genética , Adulto , Idoso , Autofagia/genética , DNA (Citosina-5-)-Metiltransferase 1 , DNA (Citosina-5-)-Metiltransferases/química , Feminino , Células HEK293 , Humanos , Masculino , Pessoa de Meia-Idade , Doenças do Sistema Nervoso/diagnóstico , Doenças do Sistema Nervoso/genética , Linhagem , Estrutura Secundária de ProteínaRESUMO
PURPOSE: Multiplex genetic testing, including both moderate- and high-penetrance genes for cancer susceptibility, is associated with greater uncertainty than traditional testing, presenting challenges to informed consent and genetic counseling. We sought to develop a new model for informed consent and genetic counseling for four ongoing studies. METHODS: Drawing from professional guidelines, literature, conceptual frameworks, and clinical experience, a multidisciplinary group developed a tiered-binned genetic counseling approach proposed to facilitate informed consent and improve outcomes of cancer susceptibility multiplex testing. RESULTS: In this model, tier 1 "indispensable" information is presented to all patients. More specific tier 2 information is provided to support variable informational needs among diverse patient populations. Clinically relevant information is "binned" into groups to minimize information overload, support informed decision making, and facilitate adaptive responses to testing. Seven essential elements of informed consent are provided to address the unique limitations, risks, and uncertainties of multiplex testing. CONCLUSION: A tiered-binned model for informed consent and genetic counseling has the potential to address the challenges of multiplex testing for cancer susceptibility and to support informed decision making and adaptive responses to testing. Future prospective studies including patient-reported outcomes are needed to inform how to best incorporate multiplex testing for cancer susceptibility into clinical practice.Genet Med 17 6, 485-492.
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Aconselhamento Genético , Predisposição Genética para Doença , Testes Genéticos/métodos , Consentimento Livre e Esclarecido , Modelos Teóricos , Neoplasias/diagnóstico , Neoplasias/genética , Testes Genéticos/ética , HumanosRESUMO
BACKGROUND: Pheochromocytomas (PCC) and paragangliomas (PGL) are neuroendocrine tumors that, although rare, are an important cause of secondary hypertension because of the high morbidity and mortality. PCC/PGL are still thought of as the "tumor of tens," with 10 % being hereditary; however, recent population based studies suggest that up to 32 % of patients have a germline mutation in one of the known common susceptibility genes (including NF1, VHL, RET, SDHB, SDHD, and SDHC). Despite this, most patients in the United States are not referred for clinical genetic testing by their physicians. We aimed to examine the mutation prevalence in a clinic-based population in the United States. METHODS: We performed a retrospective chart review of 139 consecutive patients with PCC/PGL from the medical genetics clinic at the hospital of the University of Pennsylvania from January 2004 through February 2012. RESULTS: We found a 41 % overall mutation detection rate. Twenty-six percent of the cohort had a mutation in the SDHB or SDHD genes. Of patients with at least one PGL tumor outside the adrenal gland, 53 % had an identified mutation. CONCLUSIONS: Forty-one percent of the cohort had a heritable mutation. The most commonly mutated gene was SDHB, which carries the highest risk of malignancy. These data, together with American Society of Clinical Oncology guidelines suggesting that genetic testing be performed if the risk of a hereditable mutation is at least 10 % or if it will affect medical management, strongly suggest that all patients with PCC/PGL should undergo clinical genetic testing.
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Neoplasias das Glândulas Suprarrenais/genética , Testes Genéticos , Taxa de Mutação , Paraganglioma Extrassuprarrenal/genética , Feocromocitoma/genética , Neoplasias Abdominais/genética , Adolescente , Adulto , Idoso , Criança , Feminino , Neoplasias de Cabeça e Pescoço/genética , Humanos , Masculino , Pessoa de Meia-Idade , Neurofibromina 1/genética , Neoplasias Pélvicas/genética , Guias de Prática Clínica como Assunto , Proteínas Proto-Oncogênicas c-ret/genética , Encaminhamento e Consulta , Estudos Retrospectivos , Succinato Desidrogenase/genética , Neoplasias Torácicas/genética , Proteína Supressora de Tumor Von Hippel-Lindau/genética , Adulto JovemRESUMO
INTRODUCTION: Experiences of illness change the physical body and embodiments, or the ways in which the world and the self are known through the body. When illness is anticipated, such as with inherited cancer predisposition syndromes, risk becomes embodied and shared in family groups. Embodied risk is experienced whether or not symptoms have manifested. To examine how individuals and families with genetic risk experience the world and understand their disease through their bodies, we employ Li-Fraumeni syndrome (LFS) as an exemplar. LFS is a rare, genetic, cancer predisposition syndrome with nearly 100% lifetime cancer risk starting from birth, limited opportunities for prevention, rigorous screening protocols, and early mortality. METHODS: Forty-five families, including 117 individuals aged 13-81 years, enrolled in the National Cancer Insitute's LFS study (NCT01443468) completed 66 open-ended interviews regarding LFS experiences. An interdisciplinary team used modified grounded theory to explore physical aspects of living with LFS in psychosocial contexts. FINDINGS: The physicality of living with LFS included constant monitoring of LFS bodies across the family to identify physical change that might indicate carcinogenesis. Cancer screening, risk reduction, and treatment acted as dually protective and invasive, and as an unavoidable features of LFS. Connections between family members with similar embodiments normalized aesthetic changes and supported coping with visible markers of difference. In some circumstances, participants objectified the body to preserve the self and important relationships. In others, intense pain or loss created thresholds beyond which the self could no longer be separated from the body to support coping. DISCUSSION: This paper focuses on Li-Fraumeni syndrome, a familial condition with a well-established genetic identity in which the body-self is experienced in relation to important others, to medical imaging, and to historical experiences with cancer. We expand on theories of embodied risk and inter-embodiment to describe experiences across disease trajectories, with attention to division and union between body, self, and other.
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Síndrome de Li-Fraumeni , Detecção Precoce de Câncer , Eletricidade , Família , Predisposição Genética para Doença , Humanos , Síndrome de Li-Fraumeni/complicações , Síndrome de Li-Fraumeni/diagnóstico , Síndrome de Li-Fraumeni/genéticaRESUMO
Li-Fraumeni Syndrome (LFS) is characterized by risk of multiple primary malignancies in diverse sites, pediatric onset, near complete penetrance by age 70 years, limited options for prevention, and substantial uncertainty regarding disease manifestation and prognosis. Forty-five families, including 117 individuals aged 13-81 years, enrolled in the US National Cancer Institute's Li-Fraumeni Syndrome Study completed 66 interviews regarding their LFS experiences. An interdisciplinary team used modified grounded theory to examine family distress regarding expectations of loss and change due to likely cancer diagnoses, and the consequences of this likelihood across physical, social, and emotional domains. Disease-free periods were characterized by fearful anticipation of diagnosis or recurrence, uncertainty regarding post-treatment quality of life, and planning for shifts in family dynamics to enable caregiving. The chronicity of waiting for these changes incited dread and inhibited effective coping with the pragmatic, emotional, and existential challenges of the syndrome. Consequently, families reported high burden on roles and resources and limited guidance to prepare for, or achieve resolution with, grief. Anticipatory loss, the experience of bereavement prior to an expected change, distinguishes hereditary cancer risk from a sporadic diagnosis. Such grief is often incomplete in impact or meaning, subjected to rapid or profound change as conditions worsen, and poorly understood. In this study, losses were compounded by profound uncertainty, a chronic feature of LFS, which compromised mourning. Long-term engagement of mental health providers with bereavement training, in partnership with genetics providers, can provide invaluable educational and psychological support to families as they navigate these implacable challenges.
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Luto , Família , Síndrome de Li-Fraumeni/psicologia , Incerteza , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Antecipação Psicológica , Criança , Pré-Escolar , Análise de Dados , Detecção Precoce de Câncer , Feminino , Genes p53 , Aconselhamento Genético , Pesar , Teoria Fundamentada , Esperança , Humanos , Síndrome de Li-Fraumeni/diagnóstico , Síndrome de Li-Fraumeni/genética , Masculino , Pessoa de Meia-Idade , Mutação , Prognóstico , Angústia Psicológica , Sistemas de Apoio Psicossocial , Pesquisa Qualitativa , Qualidade de Vida , Adulto JovemRESUMO
The SCN1A gene encodes for the voltage-dependent Nav1.1 Na+ channel, an isoform mainly expressed in GABAergic neurons that is the target of hundreds of epileptogenic mutations. More recently, it has been shown that the SCN1A gene is also the target of mutations responsible for familial hemiplegic migraine (FHM-3), a rare autosomal dominant subtype of migraine with aura. Studies of these mutations indicate that they induce gain of function of the channel. Surprisingly, the mutation L1649Q responsible for pure FHM-3 showed a complete loss of function, but, when partially rescued it induced an overall gain of function because of modification of the gating properties of the mutant channel. Here, we report the characterization of the L1670W SCN1A mutation that has been previously identified in a Chinese family with pure FHM-3, and that we have identified also in a Caucasian American family with pure FHM-3. Notably, one patient in our family had severe neurological deterioration after brain radiation for cancer treatment. Functional analysis of L1670W reveals that the mutation is responsible for folding/trafficking defects and, when they are rescued by incubation at lower temperature or by expression in neurons, modifications of the gating properties lead to an overall gain of function. Therefore, L1670W is the second mutation responsible for FHM-3 with this pathophysiological mechanism, showing that it may be a recurrent mechanism for Nav1.1 hemiplegic migraine mutations.
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Pheochromocytomas and paragangliomas (PCC/PGL) are the solid tumour type most commonly associated with an inherited susceptibility syndrome. However, very little is known about the somatic genetic changes leading to tumorigenesis or malignant transformation. Here we perform whole-exome sequencing on a discovery set of 21 PCC/PGL and identify somatic ATRX mutations in two SDHB-associated tumours. Targeted sequencing of a separate validation set of 103 PCC/PGL identifies somatic ATRX mutations in 12.6% of PCC/PGL. PCC/PGL with somatic ATRX mutations are associated with alternative lengthening of telomeres and clinically aggressive behaviour. This finding suggests that loss of ATRX, an SWI/SNF chromatin remodelling protein, is important in the development of clinically aggressive PCC/PGL.
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Neoplasias das Glândulas Suprarrenais/genética , DNA Helicases/genética , Exoma , Neoplasias de Cabeça e Pescoço/genética , Proteínas Nucleares/genética , Paraganglioma/genética , Feocromocitoma/genética , Neoplasias das Glândulas Suprarrenais/metabolismo , Neoplasias das Glândulas Suprarrenais/patologia , Cromatina/química , Cromatina/metabolismo , Montagem e Desmontagem da Cromatina , DNA Helicases/metabolismo , Expressão Gênica , Predisposição Genética para Doença , Neoplasias de Cabeça e Pescoço/metabolismo , Neoplasias de Cabeça e Pescoço/patologia , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Mutação , Proteínas Nucleares/metabolismo , Paraganglioma/metabolismo , Paraganglioma/patologia , Feocromocitoma/metabolismo , Feocromocitoma/patologia , Succinato Desidrogenase/genética , Succinato Desidrogenase/metabolismo , Telômero/ultraestrutura , Homeostase do Telômero , Proteína Nuclear Ligada ao XRESUMO
Genetic testing has been utilized to determine the etiology of some pediatric cardiac conditions for decades. However, new techniques, such as clinical whole exome sequencing, raise ethical challenges that must be addressed for the successful integration of these techniques into routine clinical care. One major ethical concern is the ability of patients to provide meaningful informed consent for this type of complex testing. A case of familial dilated cardiomyopathy with pediatric onset of unknown genetic etiology was utilized to facilitate the discussion of these issues by a panel including cardiologists, a geneticist, and a genetic counselor. Cardiologists and their medical genetics colleagues need to continue to discuss and investigate how to ethically integrate rapidly advancing genetic testing technologies into patient care to optimize potential benefits and minimize potential harms.