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Rubinstein-Taybi syndrome (RTS) is an archetypical genetic syndrome that is characterised by intellectual disability, well-defined facial features, distal limb anomalies and atypical growth, among numerous other signs and symptoms. It is caused by variants in either of two genes (CREBBP, EP300) which encode for the proteins CBP and p300, which both have a function in transcription regulation and histone acetylation. As a group of international experts and national support groups dedicated to the syndrome, we realised that marked heterogeneity currently exists in clinical and molecular diagnostic approaches and care practices in various parts of the world. Here, we outline a series of recommendations that document the consensus of a group of international experts on clinical diagnostic criteria for types of RTS (RTS1: CREBBP; RTS2: EP300), molecular investigations, long-term management of various particular physical and behavioural issues and care planning. The recommendations as presented here will need to be evaluated for improvements to allow for continued optimisation of diagnostics and care.
Assuntos
Proteína de Ligação a CREB , Proteína p300 Associada a E1A , Síndrome de Rubinstein-Taybi , Síndrome de Rubinstein-Taybi/genética , Síndrome de Rubinstein-Taybi/diagnóstico , Síndrome de Rubinstein-Taybi/terapia , Humanos , Proteína de Ligação a CREB/genética , Proteína p300 Associada a E1A/genética , Consenso , Gerenciamento Clínico , MutaçãoRESUMO
BACKGROUND: This study investigates the potential influence of genotype and parent-of-origin effects (POE) on the clinical manifestations of Lynch syndrome (LS) within families carrying (likely) disease-causing MSH6 germline variants. PATIENTS AND METHODS: A cohort of 1615 MSH6 variant carriers (310 LS families) was analyzed. Participants were categorized based on RNA expression and parental inheritance of the variant. Hazard ratios (HRs) were calculated using weighted Cox regression, considering external information to address ascertainment bias. The findings were cross-validated using the Prospective Lynch Syndrome Database (PLSD) for endometrial cancer (EC). RESULTS: No significant association was observed between genotype and colorectal cancer (CRC) risk (HR = 1.06, 95% confidence interval [CI]: 0.77-1.46). Patients lacking expected RNA expression exhibited a reduced risk of EC (Reference Cohort 1: HR = 0.68, 95% CI: 0.43-1.03; Reference Cohort 2: HR = 0.63, 95% CI: 0.46-0.87). However, these results could not be confirmed in the PLSD. Moreover, no association was found between POE and CRC risk (HR = 0.78, 95% CI: 0.52-1.17) or EC risk (Reference Cohort 1: HR = 0.93, 95% CI: 0.65-1.33; Reference Cohort 2: HR = 0.8, 95% CI: 0.64-1.19). DISCUSSION AND CONCLUSION: No evidence of POE was detected in MSH6 families. While RNA expression may be linked to varying risks of EC, further investigation is required to explore this observation.
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Neoplasias Colorretais Hereditárias sem Polipose , Proteínas de Ligação a DNA , Genótipo , Fenótipo , Humanos , Neoplasias Colorretais Hereditárias sem Polipose/genética , Feminino , Masculino , Proteínas de Ligação a DNA/genética , Pessoa de Meia-Idade , Adulto , Mutação em Linhagem Germinativa , Idoso , Predisposição Genética para Doença , Neoplasias do Endométrio/genética , Neoplasias do Endométrio/patologiaRESUMO
Germline SMAD4 pathogenic variants (PVs) cause juvenile polyposis syndrome (JPS), which is known for an increased risk of gastrointestinal juvenile polyps and gastrointestinal cancer. Many patients with SMAD4 PV also show signs of hereditary hemorrhagic telangiectasia (HHT) and some patients have aneurysms and dissections of the thoracic aorta. Here we describe two patients with a germline SMAD4 PV and a remarkable clinical presentation including multiple medium-sized arterial aneurysms. More data are needed to confirm whether the more extensive vascular phenotype and the other described features in our patients are indeed part of a broader JPS spectrum.
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OBJECTIVE: The aim of this study was to describe the long-term outcome of asymptomatic BRCA1/2 germline pathogenic variant (GPV) carriers with high-grade serous carcinoma (HGSC) in their risk-reducing salpingo-oophorectomy (RRSO) specimen. METHODS: In a previously described cohort of asymptomatic BRCA1/2 GPV carriers derived from the Hereditary Breast and Ovarian cancer in the Netherlands (HEBON) study, women with HGSC at RRSO were identified. Main outcome was ten-year disease-free survival (DFS). Secondary outcomes were time to recurrence, ten-year disease-specific survival (DSS), ten-year overall survival (OS). Patient, disease and treatment characteristics associated with recurrence were described. RESULTS: The 28 included women with HGSC at RRSO were diagnosed at a median age of 55.3 years (range: 33.5-74.3). After staging, eighteen women had (FIGO) stage I, three stage II and five had stage III disease. Two women did not undergo surgical staging and were classified as unknown stage. After a median follow-up of 13.5 years (range: 9.1-24.7), six women with stage I (33%), one woman with stage II (33%), two women with stage III (40%) and none of the women with unknown stage developed a recurrence. Median time to recurrence was 6.9 years (range: 0.8-9.2 years). Ten-year DFS was 68%, ten-year DSS was 88% and ten-year OS was 82%. CONCLUSION: Most asymptomatic BRCA1/2 GPV carriers with HGSC at RRSO were diagnosed at an early stage. Nevertheless, after a median follow-up of 13.5 years, nine of the 28 women with HGSC at RRSO developed a recurrence after a median of 6.9 years.
Assuntos
Cistadenocarcinoma Seroso , Mutação em Linhagem Germinativa , Neoplasias Ovarianas , Salpingo-Ooforectomia , Humanos , Feminino , Pessoa de Meia-Idade , Adulto , Idoso , Neoplasias Ovarianas/genética , Neoplasias Ovarianas/patologia , Neoplasias Ovarianas/cirurgia , Cistadenocarcinoma Seroso/genética , Cistadenocarcinoma Seroso/patologia , Cistadenocarcinoma Seroso/cirurgia , Proteína BRCA2/genética , Proteína BRCA1/genética , Recidiva Local de Neoplasia/genética , Recidiva Local de Neoplasia/prevenção & controle , Genes BRCA2 , Intervalo Livre de Doença , Genes BRCA1 , Heterozigoto , Gradação de TumoresRESUMO
BACKGROUND: Combining the faecal immunochemical test (FIT) result with risk factors for advanced neoplasia (AN) may increase the yield of colorectal cancer (CRC) screening without increasing the number of colonoscopies. We conducted a randomised controlled trial in the Dutch CRC screening programme to evaluate a previously developed risk model including FIT, age, sex, smoking status, and CRC family history. METHODS: A total of 22,748 individuals aged 56-75 years were pre-randomised to the risk-model group or the FIT-only group. Both groups received the FIT; those allocated to the risk-model group also received a single-page questionnaire. Study participants with a positive result (FIT ≥ 15 µg Hb/g faeces and/or risk ≥0.10) were referred for colonoscopy. The primary outcome measure was the proportion of invitees in whom AN was detected. RESULTS: In the risk-model group, 3113/11,364 invitees (27%) returned the FIT and questionnaire versus 3061/11,384 invitees (27%) in the FIT-only group (p = 0.40). The yield of AN was 3.70/1000 invitees in the risk-model group versus 3.43/1000 in the FIT-only group (absolute difference: 0.27/1000, 95%CI: -1.30 to 1.82, p = 0.82). CONCLUSIONS: Combining FIT with risk factors for CRC did not increase the yield of AN compared to FIT-only in an existing CRC screening programme. There was no difference in participation between groups. CLINICAL TRIAL REGISTRATION: NCT04490551 (ClinicalTrials.gov).
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Neoplasias Colorretais , Detecção Precoce de Câncer , Humanos , Colonoscopia , Neoplasias Colorretais/diagnóstico , Neoplasias Colorretais/epidemiologia , Fatores de Risco , Sangue Oculto , Fezes/química , Hemoglobinas/análise , Programas de RastreamentoRESUMO
Congenital anomalies of the kidney and urinary tract (CAKUT) constitute one of the most frequent birth defects and represent the most common cause of chronic kidney disease in the first three decades of life. Despite the discovery of dozens of monogenic causes of CAKUT, most pathogenic pathways remain elusive. We performed whole-exome sequencing (WES) in 551 individuals with CAKUT and identified a heterozygous de novo stop-gain variant in ZMYM2 in two different families with CAKUT. Through collaboration, we identified in total 14 different heterozygous loss-of-function mutations in ZMYM2 in 15 unrelated families. Most mutations occurred de novo, indicating possible interference with reproductive function. Human disease features are replicated in X. tropicalis larvae with morpholino knockdowns, in which expression of truncated ZMYM2 proteins, based on individual mutations, failed to rescue renal and craniofacial defects. Moreover, heterozygous Zmym2-deficient mice recapitulated features of CAKUT with high penetrance. The ZMYM2 protein is a component of a transcriptional corepressor complex recently linked to the silencing of developmentally regulated endogenous retrovirus elements. Using protein-protein interaction assays, we show that ZMYM2 interacts with additional epigenetic silencing complexes, as well as confirming that it binds to FOXP1, a transcription factor that has also been linked to CAKUT. In summary, our findings establish that loss-of-function mutations of ZMYM2, and potentially that of other proteins in its interactome, as causes of human CAKUT, offering new routes for studying the pathogenesis of the disorder.
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Proteínas de Ligação a DNA/genética , Epigênese Genética , Fatores de Transcrição Forkhead/genética , Mutação , Proteínas Repressoras/genética , Fatores de Transcrição/genética , Sistema Urinário/metabolismo , Anormalidades Urogenitais/genética , Proteínas de Anfíbios/antagonistas & inibidores , Proteínas de Anfíbios/genética , Proteínas de Anfíbios/metabolismo , Animais , Estudos de Casos e Controles , Criança , Pré-Escolar , Proteínas de Ligação a DNA/metabolismo , Família , Feminino , Fatores de Transcrição Forkhead/metabolismo , Heterozigoto , Humanos , Lactente , Larva/genética , Larva/crescimento & desenvolvimento , Larva/metabolismo , Masculino , Camundongos , Camundongos Knockout , Morfolinos/genética , Morfolinos/metabolismo , Linhagem , Ligação Proteica , Proteínas Repressoras/metabolismo , Fatores de Transcrição/metabolismo , Sistema Urinário/anormalidades , Anormalidades Urogenitais/metabolismo , Anormalidades Urogenitais/patologia , Sequenciamento do Exoma , XenopusRESUMO
Diagnosis of Lynch syndrome (LS) caused by a pathogenic germline MSH6 variant may be complicated by discordant immunohistochemistry (IHC) and/or by a microsatellite stable (MSS) phenotype. This study aimed to identify the various causes of the discordant phenotypes of colorectal cancer (CRC) and endometrial cancer (EC) in MSH6-associated LS. Data were collected from Dutch family cancer clinics. Carriers of a (likely) pathogenic MSH6 variant diagnosed with CRC or EC were categorized based on an microsatellite instability (MSI)/IHC test outcome that might fail to result in a diagnosis of LS (eg, retained staining of all 4 mismatch repair proteins, with or without an MSS phenotype, and other staining patterns). When tumor tissue was available, MSI and/or IHC were repeated. Next-generation sequencing (NGS) was performed in cases with discordant staining patterns. Data were obtained from 360 families with 1763 (obligate) carriers. MSH6 variant carriers with CRC or EC (n = 590) were included, consisting of 418 CRCs and 232 ECs. Discordant staining was reported in 77 cases (36% of MSI/IHC results). Twelve patients gave informed consent for further analysis of tumor material. Upon revision, 2 out of 3 MSI/IHC cases were found to be concordant with the MSH6 variant, and NGS showed that 4 discordant IHC results were sporadic rather than LS-associated tumors. In 1 case, somatic events explained the discordant phenotype. The use of reflex IHC mismatch repair testing, the current standard in most Western countries, may lead to the misdiagnosis of germline MSH6 variant carriers. The pathologist should point out that further diagnostics for inheritable colon cancer, including LS, should be considered in case of a strong positive family history. Germline DNA analysis of the mismatch repair genes, preferably as part of a larger gene panel, should therefore be considered in potential LS patients.
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Neoplasias do Colo , Neoplasias Colorretais Hereditárias sem Polipose , Neoplasias Colorretais , Neoplasias do Endométrio , Feminino , Humanos , Repetições de Microssatélites , Neoplasias Colorretais Hereditárias sem Polipose/diagnóstico , Neoplasias Colorretais Hereditárias sem Polipose/genética , Neoplasias Colorretais Hereditárias sem Polipose/patologia , Instabilidade de Microssatélites , Neoplasias do Colo/genética , Reparo de Erro de Pareamento de DNA/genética , Neoplasias do Endométrio/genética , Proteínas de Ligação a DNA/genética , Neoplasias Colorretais/patologiaRESUMO
The heterogeneous nuclear ribonucleoprotein (HNRNP) genes code for a set of RNA-binding proteins that function primarily in the spliceosome C complex. Pathogenic variants in these genes can drive neurodegeneration, through a mechanism involving excessive stress-granule formation, or developmental defects, through mechanisms that are not known. Here, we report four unrelated individuals who have truncating or missense variants in the same C-terminal region of hnRNPR and who have multisystem developmental defects including abnormalities of the brain and skeleton, dysmorphic facies, brachydactyly, seizures, and hypoplastic external genitalia. We further identified in the literature a fifth individual with a truncating variant. RNA sequencing of primary fibroblasts reveals that these HNRNPR variants drive significant changes in the expression of several homeobox genes, as well as other transcription factors, such as LHX9, TBX1, and multiple HOX genes, that are considered fundamental regulators of embryonic and gonad development. Higher levels of retained intronic HOX sequences and lost splicing events in the HOX cluster are observed in cells carrying HNRNPR variants, suggesting that impaired splicing is at least partially driving HOX deregulation. At basal levels, stress-granule formation appears normal in primary and transfected cells expressing HNRNPR variants. However, these cells reveal profound recovery defects, where stress granules fail to disassemble properly, after exposure to oxidative stress. This study establishes an essential role for HNRNPR in human development and points to a mechanism that may unify other "spliceosomopathies" linked to variants that drive multi-system congenital defects and are found in hnRNPs.
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Deficiências do Desenvolvimento/etiologia , Fibroblastos/patologia , Regulação da Expressão Gênica , Genes Homeobox/genética , Ribonucleoproteínas Nucleares Heterogêneas/genética , Mutação , Splicing de RNA/genética , Criança , Pré-Escolar , Deficiências do Desenvolvimento/patologia , Feminino , Fibroblastos/metabolismo , Humanos , Lactente , Masculino , Estresse Oxidativo , Fenótipo , Sequenciamento do ExomaRESUMO
Centronuclear myopathy (CNM) is a genetically heterogeneous congenital myopathy characterized by muscle weakness, atrophy, and variable degrees of cardiorespiratory involvement. The clinical severity is largely explained by genotype (DNM2, MTM1, RYR1, BIN1, TTN, and other rarer genetic backgrounds), specific mutation(s), and age of the patient. The histopathological hallmark of CNM is the presence of internal centralized nuclei on muscle biopsy. Information on the phenotypical spectrum, subtype prevalence, and phenotype-genotype correlations is limited. To characterize CNM more comprehensively, we retrospectively assessed a national cohort of 48 CNM patients (mean age = 32 ± 24 years, range 0-80, 54% males) from the Netherlands clinically, histologically, and genetically. All information was extracted from entries in the patient's medical records, between 2000 and 2020. Frequent clinical features in addition to muscle weakness and hypotonia were fatigue and exercise intolerance in more mildly affected cases. Genetic analysis showed variants in four genes (18 DNM2, 14 MTM1, 9 RYR1, and 7 BIN1), including 16 novel variants. In addition to central nuclei, histologic examination revealed a large variability of myopathic features in the different genotypes. The identification and characterization of these patients contribute to trial readiness.
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Estudos de Associação Genética , Predisposição Genética para Doença , Miopatias Congênitas Estruturais/diagnóstico , Miopatias Congênitas Estruturais/genética , Fenótipo , Adolescente , Adulto , Idade de Início , Idoso , Idoso de 80 Anos ou mais , Alelos , Substituição de Aminoácidos , Biomarcadores , Biópsia , Criança , Pré-Escolar , Estudos Transversais , Feminino , Genes Ligados ao Cromossomo X , Estudos de Associação Genética/métodos , Genótipo , Histocitoquímica , Humanos , Incidência , Lactente , Recém-Nascido , Masculino , Pessoa de Meia-Idade , Mutação , Miopatias Congênitas Estruturais/epidemiologia , Países Baixos , Adulto JovemRESUMO
INTRODUCTION: Pigmentary mosaicism (PM) manifests by pigmentation anomalies along Blaschko's lines and represents a clue toward the molecular diagnosis of syndromic intellectual disability (ID). Together with new insights on the role for lysosomal signalling in embryonic stem cell differentiation, mutations in the X-linked transcription factor 3 (TFE3) have recently been reported in five patients. Functional analysis suggested these mutations to result in ectopic nuclear gain of functions. MATERIALS AND METHODS: Subsequent data sharing allowed the clustering of de novo TFE3 variants identified by exome sequencing on DNA extracted from leucocytes in patients referred for syndromic ID with or without PM. RESULTS: We describe the detailed clinical and molecular data of 17 individuals harbouring a de novo TFE3 variant, including the patients that initially allowed reporting TFE3 as a new disease-causing gene. The 12 females and 5 males presented with pigmentation anomalies on Blaschko's lines, severe ID, epilepsy, storage disorder-like features, growth retardation and recognisable facial dysmorphism. The variant was at a mosaic state in at least two male patients. All variants were missense except one splice variant. Eleven of the 13 variants were localised in exon 4, 2 in exon 3, and 3 were recurrent variants. CONCLUSION: This series further delineates the specific storage disorder-like phenotype with PM ascribed to de novo TFE3 mutation in exons 3 and 4. It confirms the identification of a novel X-linked human condition associated with mosaicism and dysregulation within the mechanistic target of rapamycin (mTOR) pathway, as well as a link between lysosomal signalling and human development.
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Fatores de Transcrição de Zíper de Leucina e Hélice-Alça-Hélix Básicos/genética , Epilepsia/genética , Deficiência Intelectual/genética , Transtornos da Pigmentação/genética , Adolescente , Adulto , Criança , Pré-Escolar , Epilepsia/complicações , Epilepsia/patologia , Feminino , Genes Ligados ao Cromossomo X/genética , Humanos , Lactente , Deficiência Intelectual/complicações , Deficiência Intelectual/patologia , Masculino , Mosaicismo , Patologia Molecular/normas , Transtornos da Pigmentação/complicações , Transtornos da Pigmentação/patologia , Sequenciamento do Exoma , Adulto JovemRESUMO
BACKGROUND: Distinguishing congenital pulmonary airway malformations (CPAMs) from pleuropulmonary blastoma (PPB) can be challenging. Previously diagnosed patients with CPAM may have been misdiagnosed and we may have missed DICER1-associated PPBs, a diagnosis with important clinical implications for patients and their families. To gain insight in potential misdiagnoses, we systematically assessed somatic DICER1 gene mutation status in an unselected, retrospective cohort of patients with a CPAM diagnosis. METHODS: In the Amsterdam University Medical Center (the Netherlands), it has been standard policy to resect CPAM lesions. We included all consecutive cases of children (age 0-18 years) with a diagnosis of CPAM between 2007 and 2017 at this center. Clinical and radiographic features were reviewed, and DICER1 gene sequencing was performed on DNA retrieved from CPAM tissue samples. RESULTS: Twenty-eight patients with a surgically removed CPAM were included. CPAM type 1 and type 2 were the most common subtypes (n = 12 and n = 13). For 21 patients a chest CT scan was available for reassessment by two pediatric radiologists. In 9 patients (9/21, 43%) the CPAM subtype scored by the radiologists did not correspond with the subtype given at pathology assessment. No pathogenic mutations and no copy number variations of the DICER1 gene were found in the DNA extracted from CPAM tissue (0/28). CONCLUSIONS: Our findings suggest that the initial CPAM diagnoses were correct. These findings should be validated through larger studies to draw conclusions regarding whether systematic DICER1 genetic testing is required in children with a pathological confirmed diagnosis of CPAM or not. LEVEL OF EVIDENCE: Level IV.
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Malformação Adenomatoide Cística Congênita do Pulmão , Blastoma Pulmonar , Criança , Humanos , Recém-Nascido , Lactente , Pré-Escolar , Adolescente , Estudos de Coortes , Estudos Retrospectivos , Blastoma Pulmonar/diagnóstico , Blastoma Pulmonar/genética , Blastoma Pulmonar/cirurgia , Malformação Adenomatoide Cística Congênita do Pulmão/diagnóstico por imagem , Malformação Adenomatoide Cística Congênita do Pulmão/genética , Malformação Adenomatoide Cística Congênita do Pulmão/cirurgia , DNA , Ribonuclease III/genética , RNA Helicases DEAD-box/genéticaRESUMO
Anaplastic lymphoma kinase (ALK) mutations occur in 3% to 11% of neuroblastoma (NBL) cases and are associated with high ALK levels. However, high ALK levels appear to be a mutation-independent hallmark of NBL. Evidence about the prognostic relevance of ALK mutations and ALK tumor positivity in patients with NBL has been inconclusive. In this study, we investigated the prognostic relevance of ALK positivity by IHC and ALK mutation status by PCR sequencing in 71 NBL, 12 ganglioneuroblastoma (GNBL), and 20 ganglioneuroma samples in a multivariate model. ALK mutations were present in 2 of 72 NBL and 2 of 12 GNBL samples, which all contained many ALK-positive cells (>50%). In addition, half of all NBL samples showed ALK positivity in most (>50%) of tumor cells, whereas half of the GNBL showed staining in <20% of the tumor cells. In most ganglioneuroma samples, a low percentage of tumor cells stained positive for ALK, which mainly involved ganglion cells. Higher percentages of ALK-positive cells in NBL and GNBL patient samples correlated with inferior survival in univariate and multivariate analyses with established prognostic factors, such as stage, age, and MYCN status. In conclusion, ALK positivity by IHC is an independent, poor prognostic factor in patients with GNBL and NBL. ALK IHC is an easy test suitable for future risk stratification in patients with NBL and GNBL.
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Ganglioneuroblastoma/metabolismo , Neuroblastoma/metabolismo , Receptores Proteína Tirosina Quinases/metabolismo , Quinase do Linfoma Anaplásico , Criança , Pré-Escolar , Feminino , Ganglioneuroblastoma/mortalidade , Humanos , Imuno-Histoquímica , Masculino , Proteína Proto-Oncogênica N-Myc , Neuroblastoma/mortalidade , Proteínas Nucleares/genética , Proteínas Oncogênicas/genética , Mutação Puntual/genética , Prognóstico , Receptores Proteína Tirosina Quinases/genéticaRESUMO
BACKGROUND: Among the most commonly applied microarray normalization methods are intensity-dependent normalization methods such as lowess or loess algorithms. Their computational complexity makes them slow and thus less suitable for normalization of large datasets. Current implementations try to circumvent this problem by using a random subset of the data for normalization, but the impact of this modification has not been previously assessed. We developed a novel intensity-dependent normalization method for microarrays that is fast, simple and can include weighing of observations. RESULTS: Our normalization method is based on the P-spline scatterplot smoother using all data points for normalization. We show that using a random subset of the data for normalization should be avoided as unstable results can be produced. However, in certain cases normalization based on an invariant subset is desirable, for example, when groups of samples before and after intervention are compared. We show in the context of DNA methylation arrays that a constant weighted P-spline normalization yields a more reliable normalization curve than the one obtained by normalization on the invariant subset only. CONCLUSIONS: Our novel intensity-dependent normalization method is simpler and faster than current loess algorithms, and can be applied to one- and two-colour array data, similar to normalization based on loess. AVAILABILITY: An implementation of the method is currently available as an R package called TurboNorm from www.bioconductor.org.
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Ensaios de Triagem em Larga Escala/normas , Análise em Microsséries/métodos , Análise em Microsséries/normas , Biologia Computacional/métodos , Biologia Computacional/normas , Ensaios de Triagem em Larga Escala/métodos , Humanos , Distribuição Aleatória , Padrões de Referência , Software , Fatores de Tempo , Estudos de Validação como AssuntoRESUMO
Biallelic MSH3 germline variants are a rare cause of adenomatous polyposis as yet reported in two small families only. We describe the phenotype of a third family, the largest thus far, with adenomatous polyposis related to compound heterozygous MSH3 pathogenic variants. The index patient was a 55-years old male diagnosed with rectal cancer and adenomatous polyposis (cumulatively 52 polyps), with a family history of colorectal polyposis with unknown cause. Next-generation sequencing and copy number variation analysis of a panel of genes associated with colorectal cancer and polyposis revealed compound heterozygous germline pathogenic variants in the MSH3 gene. Nine out of 11 siblings were genotyped. Three siblings carried the same compound heterozygous MSH3 variants. Colonoscopy screening showed predominantly right-sided adenomatous polyposis in all compound heterozygous siblings, with a cumulative number of adenomas ranging from 18 to 54 in an average of four colonoscopies, and age at first adenoma detection ranging from 46 to 59. Microsatellite analysis demonstrated alterations at selected tetranucleotide repeats (EMAST) in DNA retrieved from the rectal adenocarcinoma, colorectal adenomas as well as of normal colonic mucosa. Gastro-duodenoscopy did not reveal adenomas in any of the four patients. Extra-intestinal findings included a ductal adenocarcinoma in ectopic breast tissue in one female sibling at the age of 46, and liver cysts in three affected siblings. None of the three heterozygous or wild type siblings who previously underwent colonoscopy had adenomatous polyposis. We conclude that biallelic variants in MSH3 are a rare cause of attenuated adenomatous polyposis with an onset in middle age.
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Adenocarcinoma , Adenoma , Polipose Adenomatosa do Colo , Neoplasias Colorretais , Masculino , Humanos , Feminino , Variações do Número de Cópias de DNA , Polipose Adenomatosa do Colo/diagnóstico , Neoplasias Colorretais/genética , Adenoma/genética , Proteína 3 Homóloga a MutS/genéticaRESUMO
Uncertainty is increasingly discussed during genetic counseling due to innovative techniques, e.g., multigene panel testing. Discussions about uncertainty may impact counselees variably, depending on counselors' communication styles. Ideally, the discussion of uncertainty enables counselees to cope with uncertainty and make well-informed decisions about testing. We examined the impact of how counselors convey uncertainty and address counselees' uncertainty, and explored the role of individual characteristics. Therefore, a randomized controlled experiment using videos was conducted. Former counselees (N = 224) viewed one video depicting a genetic consultation about multigene panel testing. The extent of counselors' communication of uncertainty (comprehensive vs. the essence) and their response to counselees' uncertainty expressions (providing information vs. providing space for emotions vs. normalizing and counterbalancing uncertainty) were systematically manipulated. Individual characteristics, e.g., uncertainty tolerance, were assessed, as well as outcome variables (primary outcomes: feelings of uncertainty and information recall). No effects were found on primary outcomes. Participants were most satisfied when the essence was communicated, combined with providing information or providing space responses (p = 0.002). Comprehensive information resulted in less perceived steering toward testing (p = 0.005). Participants with lower uncertainty tolerance or higher trait anxiety were less confident about their understanding when receiving comprehensive information (p = 0.025). Participants seeking information experienced less uncertainty (p = 0.003), and trusted their counselor more (p = 0.028), when the counselor used information providing responses. In sum, the impact of discussing uncertainty primarily depends on individual characteristics. Practical guidelines should address how to tailor the discussion of uncertainty.
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Aconselhamento Genético/métodos , Neoplasias/genética , Incerteza , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Aconselhamento Genético/psicologia , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias/diagnóstico , Satisfação do Paciente , Revelação da VerdadeRESUMO
Variants in the KIF1A gene can cause autosomal recessive spastic paraplegia 30, autosomal recessive hereditary sensory neuropathy, or autosomal (de novo) dominant mental retardation type 9. More recently, variants in KIF1A have also been described in a few cases with autosomal dominant spastic paraplegia. Here, we describe 20 KIF1A variants in 24 patients from a clinical exome sequencing cohort of 347 individuals with a mostly 'pure' spastic paraplegia. In these patients, spastic paraplegia was slowly progressive and mostly pure, but with a highly variable disease onset (0-57 years). Segregation analyses showed a de novo occurrence in seven cases, and a dominant inheritance pattern in 11 families. The motor domain of KIF1A is a hotspot for disease causing variants in autosomal dominant spastic paraplegia, similar to mental retardation type 9 and recessive spastic paraplegia type 30. However, unlike these allelic disorders, dominant spastic paraplegia was also caused by loss-of-function variants outside this domain in six families. Finally, three missense variants were outside the motor domain and need further characterization. In conclusion, KIF1A variants are a frequent cause of autosomal dominant spastic paraplegia in our cohort (6-7%). The identification of KIF1A loss-of-function variants suggests haploinsufficiency as a possible mechanism in autosomal dominant spastic paraplegia.
Assuntos
Cinesinas/genética , Paraplegia Espástica Hereditária/genética , Adolescente , Adulto , Criança , Pré-Escolar , Feminino , Genes Dominantes , Humanos , Lactente , Cinesinas/química , Masculino , Pessoa de Meia-Idade , Mutação de Sentido Incorreto , Linhagem , Domínios Proteicos , Paraplegia Espástica Hereditária/patologiaRESUMO
Self-renewal and differentiation of pluripotent murine embryonic stem cells (ESCs) is regulated by extrinsic signaling pathways. It is less clear whether cellular metabolism instructs developmental progression. In an unbiased genome-wide CRISPR/Cas9 screen, we identified components of a conserved amino-acid-sensing pathway as critical drivers of ESC differentiation. Functional analysis revealed that lysosome activity, the Ragulator protein complex, and the tumor-suppressor protein Folliculin enable the Rag GTPases C and D to bind and seclude the bHLH transcription factor Tfe3 in the cytoplasm. In contrast, ectopic nuclear Tfe3 represses specific developmental and metabolic transcriptional programs that are associated with peri-implantation development. We show differentiation-specific and non-canonical regulation of Rag GTPase in ESCs and, importantly, identify point mutations in a Tfe3 domain required for cytoplasmic inactivation as potentially causal for a human developmental disorder. Our work reveals an instructive and biomedically relevant role of metabolic signaling in licensing embryonic cell fate transitions.
Assuntos
Fatores de Transcrição de Zíper de Leucina e Hélice-Alça-Hélix Básicos/metabolismo , Diferenciação Celular , Lisossomos/metabolismo , Transdução de Sinais , Alelos , Animais , Autorrenovação Celular , Feminino , GTP Fosfo-Hidrolases/metabolismo , Genoma , Humanos , Masculino , Camundongos , Células-Tronco Embrionárias Murinas/citologia , Células-Tronco Embrionárias Murinas/metabolismo , Células-Tronco Neurais/citologia , Células-Tronco Neurais/metabolismo , Fosforilação , Mutação Puntual/genética , Ligação Proteica , Transcrição GênicaRESUMO
Context: Pituitary stalk interruption syndrome (PSIS) consists of a small/absent anterior pituitary lobe, an interrupted/absent pituitary stalk, and an ectopic posterior pituitary lobe. Mendelian forms of PSIS are detected infrequently (<5%), and a polygenic etiology has been suggested. GLI2 variants have been reported at a relatively high frequency in PSIS. Objective: To provide further evidence for a non-Mendelian, polygenic etiology of PSIS. Methods: Exome sequencing (trio approach) in 20 patients with isolated PSIS. In addition to searching for (potentially) pathogenic de novo and biallelic variants, a targeted search was performed in a panel of genes associated with midline brain development (223 genes). For GLI2 variants, both (potentially) pathogenic and relatively rare variants (<5% in the general population) were studied. The frequency of GLI2 variants was compared with that of a reference population. Results: We found four additional candidate genes for isolated PSIS (DCHS1, ROBO2, CCDC88C, and KIF14) and one for syndromic PSIS (KAT6A). Eleven GLI2 variants were present in six patients. A higher frequency of a combination of two GLI2 variants (M1352V + D1520N) was found in the study group compared with a reference population (10% vs 0.68%). (Potentially) pathogenic variants were identified in genes associated with midline brain anomalies, including holoprosencephaly, hypogonadotropic hypogonadism, and absent corpus callosum and in genes involved in ciliopathies. Conclusion: Combinations of variants in genes associated with midline brain anomalies are frequently present in PSIS and sustain the hypothesis of a polygenic cause of PSIS.
Assuntos
Análise Mutacional de DNA/métodos , Testes Genéticos/métodos , Herança Multifatorial , Doenças da Hipófise/genética , Hipófise/anormalidades , Adolescente , Adulto , Criança , Pré-Escolar , Exoma , Feminino , Predisposição Genética para Doença , Humanos , Lactente , Recém-Nascido , Masculino , Herança Multifatorial/genética , Doenças da Hipófise/congênito , Análise de Sequência de DNA/métodos , Síndrome , Adulto JovemRESUMO
Hotspot mutations in the promoter of the telomerase reverse transcriptase (TERT) gene have been recently reported in human cancers and proposed as a novel mechanism of telomerase activation. To explore TERT promoter mutations in tumors originating from the adrenal gland and extra-adrenal paraganglia, a set of 253 tumors (38 adrenocortical carcinomas (ACCs), 127 pheochromocytomas (PCCs), 18 extra-adrenal paragangliomas (ea PGLs), 37 head and neck PGLs (HN PGLs), and 33 peripheral neuroblastic tumors) was selected along with 16 human neuroblastoma (NBL) and two ACC cell lines to assess TERT promoter mutations by the Sanger sequencing method. All mutations detected were confirmed by a SNaPshot assay. Additionally, 36 gastrointestinal stromal tumors (GISTs) were added to explore an association between TERT promoter mutations and SDH deficiency. TERT promoter mutations were found in seven out of 289 tumors and in three out of 18 human cell lines; four C228T mutations in 38 ACCs (10.5%), two C228T mutations in 18 ea PGLs (11.1%), one C250T mutation in 36 GISTs (2.8%), and three C228T mutations in 16 human NBL cell lines (18.75%). No mutation was detected in PCCs, HN PGLs, neuroblastic tumors as well as ACC cell lines. TERT promoter mutations preferentially occurred in a SDH-deficient setting (P=0.01) being present in three out of 47 (6.4%) SDH-deficient tumors vs zero out of 171 (0%) SDH-intact tumors. We conclude that TERT promoter mutations occur in ACCs and ea PGLs. In addition, preliminary evidence indicates a potential association with the acquisition of TERT promoter mutations in SDH-deficient tumors.
Assuntos
Neoplasias do Córtex Suprarrenal/genética , Carcinoma Adrenocortical/genética , Paraganglioma/genética , Regiões Promotoras Genéticas/genética , Telomerase/genética , Adulto , Linhagem Celular Tumoral , Feminino , Neoplasias de Cabeça e Pescoço/genética , Humanos , Masculino , Pessoa de Meia-Idade , Mutação , Neuroblastoma/genética , Feocromocitoma/genéticaRESUMO
Neuroblastomas (NBL) are common pediatric solid tumors with a variable clinical course. At diagnosis half of all neuroblastoma patients presents with metastatic disease. The mechanisms of metastasis are largely unknown. Gene expression profiles (HU133plus2.0 arrays, Affymetrix) of 17 NBL and 5 peripheral neuro-ectodermal cell lines were used to identify a subgroup of non-MYCN amplified (non-NMA) NBL cell lines with a distinct gene expression profile and characterized by high expression of AXL. Axl is a tyrosine kinase receptor which plays a role in the metastatic process of several types of cancer. We hypothesized that Axl contributes to the metastasizing potential of non-NMA NBL and tested if AXL silencing diminishes malignant properties of high Axl expressing cell lines. AXL was silenced in two non-NMA NBL cell lines by using a lentiviral shRNA construct that was able to transduce these cell lines with more than 90% infection efficiency. Axl mRNA and protein level were efficiently knocked-down resulting in a decrease of migration of Axl positive cell lines GI-M-EN and SH-EP-2, and decreased invasion of GI-M-EN. Morphologically, Axl knockdown induced more rounded cells with a loss of contact. Intracellularly, we observed induction of stress fibers (immunofluorescence F-actin). These changes in cytoskeleton were associated with decreased migration, but were not accompanied by changes in genes involved in epithelial to mesenchymal transition such as CDH2, VIM or MMP9. No effects were observed for cell proliferation, apoptosis or downstream pathways. In conclusion, AXL is identified as a possible mediator of NBL metastasis.