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1.
JAMA Otolaryngol Head Neck Surg ; 149(3): 212-222, 2023 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-36633841

RESUMO

Importance: In the US, most childhood-onset bilateral sensorineural hearing loss is genetic, with more than 120 genes and thousands of different alleles known. Primary treatments are hearing aids and cochlear implants. Genetic diagnosis can inform progression of hearing loss, indicate potential syndromic features, and suggest best timing for individualized treatment. Objective: To identify the genetic causes of childhood-onset hearing loss and characterize severity, progression, and cochlear implant success associated with genotype in a single large clinical cohort. Design, Setting, and Participants: This cross-sectional analysis (genomics) and retrospective cohort analysis (audiological measures) were conducted from 2019 to 2022 at the otolaryngology and audiology clinics of Seattle Children's Hospital and the University of Washington and included 449 children from 406 families with bilateral sensorineural hearing loss with an onset younger than 18 years. Data were analyzed between January and June 2022. Main Outcomes and Measures: Genetic diagnoses based on genomic sequencing and structural variant analysis of the DNA of participants; severity and progression of hearing loss as measured by audiologic testing; and cochlear implant success as measured by pediatric and adult speech perception tests. Hearing thresholds and speech perception scores were evaluated with respect to age at implant, months since implant, and genotype using a multivariate analysis of variance and covariance. Results: Of 406 participants, 208 (51%) were female, 17 (4%) were African/African American, 32 (8%) were East Asian, 219 (54%) were European, 53 (13%) were Latino/Admixed American, and 16 (4%) were South Asian. Genomic analysis yielded genetic diagnoses for 210 of 406 families (52%), including 55 of 82 multiplex families (67%) and 155 of 324 singleton families (48%). Rates of genetic diagnosis were similar for children of all ancestries. Causal variants occurred in 43 different genes, with each child (with 1 exception) having causative variant(s) in only 1 gene. Hearing loss severity, affected frequencies, and progression varied by gene and, for some genes, by genotype within gene. For children with causative mutations in MYO6, OTOA, SLC26A4, TMPRSS3, or severe loss-of-function variants in GJB2, hearing loss was progressive, with losses of more than 10 dB per decade. For all children with cochlear implants, outcomes of adult speech perception tests were greater than preimplanted levels. Yet the degree of success varied substantially by genotype. Adjusting for age at implant and interval since implant, speech perception was highest for children with hearing loss due to MITF or TMPRSS3. Conclusions and Relevance: The results of this cross-sectional study suggest that genetic diagnosis is now sufficiently advanced to enable its integration into precision medical care for childhood-onset hearing loss.


Assuntos
Implante Coclear , Implantes Cocleares , Surdez , Perda Auditiva Neurossensorial , Perda Auditiva , Percepção da Fala , Adulto , Feminino , Criança , Humanos , Masculino , Estudos Transversais , Estudos Retrospectivos , Surdez/cirurgia , Perda Auditiva Neurossensorial/diagnóstico , Perda Auditiva Neurossensorial/genética , Perda Auditiva Neurossensorial/cirurgia , Perda Auditiva Bilateral/diagnóstico , Perda Auditiva Bilateral/genética , Proteínas de Membrana , Proteínas de Neoplasias , Serina Endopeptidases
2.
J Allergy Clin Immunol ; 149(1): 327-339, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-33864888

RESUMO

BACKGROUND: Most patients with childhood-onset immune dysregulation, polyendocrinopathy, and enteropathy have no genetic diagnosis for their illness. These patients may undergo empirical immunosuppressive treatment with highly variable outcomes. OBJECTIVE: We sought to determine the genetic basis of disease in patients referred with Immune dysregulation, polyendocrinopathy, enteropathy, X-linked-like (IPEX-like) disease, but with no mutation in FOXP3; then to assess consequences of genetic diagnoses for clinical management. METHODS: Genomic DNA was sequenced using a panel of 462 genes implicated in inborn errors of immunity. Candidate mutations were characterized by genomic, transcriptional, and (for some) protein analysis. RESULTS: Of 123 patients with FOXP3-negative IPEX-like disease, 48 (39%) carried damaging germline mutations in 1 of the following 27 genes: AIRE, BACH2, BCL11B, CARD11, CARD14, CTLA4, IRF2BP2, ITCH, JAK1, KMT2D, LRBA, MYO5B, NFKB1, NLRC4, POLA1, POMP, RAG1, SH2D1A, SKIV2L, STAT1, STAT3, TNFAIP3, TNFRSF6/FAS, TNRSF13B/TACI, TOM1, TTC37, and XIAP. Many of these genes had not been previously associated with an IPEX-like diagnosis. For 42 of the 48 patients with genetic diagnoses, knowing the critical gene could have altered therapeutic management, including recommendations for targeted treatments and for or against hematopoietic cell transplantation. CONCLUSIONS: Many childhood disorders now bundled as "IPEX-like" disease are caused by individually rare, severe mutations in immune regulation genes. Most genetic diagnoses of these conditions yield clinically actionable findings. Barriers are lack of testing or lack of repeat testing if older technologies failed to provide a diagnosis.


Assuntos
Diabetes Mellitus Tipo 1/congênito , Diarreia/genética , Doenças Genéticas Ligadas ao Cromossomo X/genética , Doenças do Sistema Imunitário/congênito , Adolescente , Criança , Pré-Escolar , Diabetes Mellitus Tipo 1/diagnóstico , Diabetes Mellitus Tipo 1/genética , Diabetes Mellitus Tipo 1/terapia , Diarreia/diagnóstico , Diarreia/terapia , Feminino , Expressão Gênica , Doenças Genéticas Ligadas ao Cromossomo X/diagnóstico , Doenças Genéticas Ligadas ao Cromossomo X/terapia , Transplante de Células-Tronco Hematopoéticas , Humanos , Doenças do Sistema Imunitário/diagnóstico , Doenças do Sistema Imunitário/genética , Doenças do Sistema Imunitário/terapia , Lactente , Recém-Nascido , Masculino , Mutação
3.
Otol Neurotol ; 42(8): e1143-e1151, 2021 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-34049328

RESUMO

OBJECTIVES: To better distinguish NOG-related-symphalangism spectrum disorder (NOG-SSD) from chromosomal 17q22 microdeletion syndromes and to inform surgical considerations in stapes surgery for patients with NOG-SSD. BACKGROUND: Mutations in NOG cause a variety of skeletal syndromes that often include conductive hearing loss. Several microdeletions of chromosome 17q22 lead to severe syndromes with clinical characteristics that overlap NOG-SSD. Isolated deletion of NOG has not been described, and therefore the contribution of NOG deletion in these syndromes is unknown. METHODS: Two families with autosomal dominant NOG-SSD exhibited stapes ankylosis, facial dysmorphisms, and skeletal and joint anomalies. In each family, NOG was evaluated by genomic sequencing and candidate mutations confirmed as damaging by in vitro assays. Temporal bone histology of a patient with NOG-SSD was compared with temporal bones of 40 patients diagnosed with otosclerosis. RESULTS: Family 1 harbors a 555 kb chromosomal deletion encompassing only NOG and ANKFN1. Family 2 harbors a missense mutation in NOG leading to absence of noggin protein. The incus-footplate distance of the temporal bone was significantly longer in a patient with NOG-SSD than in patients with otosclerosis. CONCLUSION: The chromosomal microdeletion of family 1 led to a phenotype comparable to that due to a NOG point mutation and much milder than the phenotypes due to other chromosome 17q22 microdeletions. Severe clinical findings in other microdeletion cases are likely due to deletion of genes other than NOG. Based on temporal bone findings, we recommend that surgeons obtain longer stapes prostheses before stapes surgery in individuals with NOG-SSD stapes ankylosis.


Assuntos
Deformidades Congênitas do Pé , Deformidades Congênitas da Mão , Sinostose , Ossos do Carpo/anormalidades , Heterogeneidade Genética , Humanos , Estribo/anormalidades , Sinostose/genética , Ossos do Tarso/anormalidades
5.
NPJ Breast Cancer ; 7(1): 6, 2021 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-33479248

RESUMO

The Carolina Breast Cancer Study (CBCS) phases I-II was a case-control study of biological and social risk factors for invasive breast cancer that enrolled cases and controls between 1993 and 1999. Case selection was population-based and stratified by ancestry and age at diagnosis. Controls were matched to cases by age, self-identified race, and neighborhood of residence. Sequencing genomic DNA from 1370 cases and 1635 controls yielded odds ratios (with 95% confidence limits) for breast cancer of all subtypes of 26.7 (3.59, 189.1) for BRCA1, 8.8 (3.44, 22.48) for BRCA2, and 9.0 (2.06, 39.60) for PALB2; and for triple-negative breast cancer (TNBC) of 55.0 (7.01, 431.4) for BRCA1, 12.1 (4.18, 35.12) for BRCA2, and 10.8 (1.97, 59.11) for PALB2. Overall, 5.6% of patients carried a pathogenic variant in BRCA1, BRCA2, PALB2, or TP53, the four most highly penetrant breast cancer genes. Analysis of cases by tumor subtype revealed the expected association of TNBC versus other tumor subtypes with BRCA1, and suggested a significant association between TNBC versus other tumor subtypes with BRCA2 or PALB2 among African-American (AA) patients [2.95 (1.18, 7.37)], but not among European-American (EA) patients [0.62 (0.18, 2.09)]. AA patients with pathogenic variants in BRCA2 or PALB2 were 11 times more likely to be diagnosed with TNBC versus another tumor subtype than were EA patients with pathogenic variants in either of these genes (P = 0.001). If this pattern is confirmed in other comparisons of similarly ascertained AA and EA breast cancer patients, it could in part explain the higher prevalence of TNBC among AA breast cancer patients.

6.
J Med Genet ; 58(12): 850-852, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-33060287

RESUMO

Current clinical approaches for mutation discovery are based on short sequence reads (100-300 bp) of exons and flanking splice sites targeted by multigene panels or whole exomes. Short-read sequencing is highly accurate for detection of single nucleotide variants, small indels and simple copy number differences but is of limited use for identifying complex insertions and deletions and other structural rearrangements. We used CRISPR-Cas9 to excise complete BRCA1 and BRCA2 genomic regions from lymphoblast cells of patients with breast cancer, then sequenced these regions with long reads (>10 000 bp) to fully characterise all non-coding regions for structural variation. In a family severely affected with early-onset bilateral breast cancer and with negative (normal) results by gene panel and exome sequencing, we identified an intronic SINE-VNTR-Alu retrotransposon insertion that led to the creation of a pseudoexon in the BRCA1 message and introduced a premature truncation. This combination of CRISPR-Cas9 excision and long-read sequencing reveals a class of complex, damaging and otherwise cryptic mutations that may be particularly frequent in tumour suppressor genes replete with intronic repeats.


Assuntos
Proteína BRCA1/genética , Sistemas CRISPR-Cas , Genes Supressores de Tumor , Mutação , Análise de Sequência de DNA/métodos , Proteína BRCA2/genética , Neoplasias da Mama/genética , Éxons/genética , Saúde da Família , Feminino , Mutação em Linhagem Germinativa , Humanos , Íntrons/genética , Mutagênese Insercional , Regiões Promotoras Genéticas/genética , Sequências Reguladoras de Ácido Nucleico/genética , Reprodutibilidade dos Testes , Retroelementos/genética
7.
Blood Adv ; 4(19): 4873-4886, 2020 10 13.
Artigo em Inglês | MEDLINE | ID: mdl-33035329

RESUMO

Telomere biology disorders (TBDs) present heterogeneously, ranging from infantile bone marrow failure associated with very short telomeres to adult-onset interstitial lung disease (ILD) with normal telomere length. Yield of genetic testing and phenotypic spectra for TBDs caused by the expanding list of telomere genes in adults remain understudied. Thus, we screened adults aged ≥18 years with a personal and/or family history clustering hematologic disorders and/or ILD enrolled on The University of Chicago Inherited Hematologic Disorders Registry for causative variants in 13 TBD genes. Sixteen (10%) of 153 probands carried causative variants distributed among TERT (n = 6), TERC (n = 4), PARN (n = 5), or RTEL1 (n = 1), of which 19% were copy number variants. The highest yield (9 of 22 [41%]) was in families with mixed hematologic and ILD presentations, suggesting that ILD in hematology populations and hematologic abnormalities in ILD populations warrant TBD genetic testing. Four (3%) of 117 familial hematologic disorder families without ILD carried TBD variants, making TBD second to only DDX41 in frequency for genetic diagnoses in this population. Phenotypes of 17 carriers with heterozygous PARN variants included 4 (24%) with hematologic abnormalities, 67% with lymphocyte telomere lengths measured by flow cytometry and fluorescence in situ hybridization at or above the 10th percentile, and a high penetrance for ILD. Alternative etiologies for cytopenias and/or ILD such as autoimmune features were noted in multiple TBD families, emphasizing the need to maintain clinical suspicion for a TBD despite the presence of alternative explanations.


Assuntos
Hematologia , Telomerase , Biologia , Hibridização in Situ Fluorescente , Mutação , Fenótipo , Prevalência , Telomerase/genética , Telomerase/metabolismo , Telômero/genética , Telômero/metabolismo
8.
PLoS One ; 15(9): e0239197, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32997669

RESUMO

Mutations in BRCA1 and BRCA2 cause deficiencies in homologous recombination repair (HR), resulting in repair of DNA double-strand breaks by the alternative non-homologous end-joining pathway, which is more error prone. HR deficiency of breast tumors is important because it is associated with better responses to platinum salt therapies and PARP inhibitors. Among other consequences of HR deficiency are characteristic somatic-mutation signatures and gene-expression patterns. The term "BRCA-like" (or "BRCAness") describes tumors that harbor an HR defect but have no detectable germline mutation in BRCA1 or BRCA2. A better understanding of the genes and molecular events associated with tumors being BRCA-like could provide mechanistic insights and guide development of targeted treatments. Using data from The Cancer Genome Atlas (TCGA) for 1101 breast-cancer patients, we identified individuals with a germline mutation, somatic mutation, homozygous deletion, and/or hypermethylation event in BRCA1, BRCA2, and 59 other cancer-predisposition genes. Based on the assumption that BRCA-like events would have similar downstream effects on tumor biology as BRCA1/BRCA2 germline mutations, we quantified these effects based on somatic-mutation signatures and gene-expression profiles. We reduced the dimensionality of the somatic-mutation signatures and expression data and used a statistical resampling approach to quantify similarities among patients who had a BRCA1/BRCA2 germline mutation, another type of aberration in BRCA1 or BRCA2, or any type of aberration in one of the other genes. Somatic-mutation signatures of tumors having a non-germline aberration in BRCA1/BRCA2 (n = 80) were generally similar to each other and to tumors from BRCA1/BRCA2 germline carriers (n = 44). Additionally, somatic-mutation signatures of tumors with germline or somatic events in ATR (n = 16) and BARD1 (n = 8) showed high similarity to tumors from BRCA1/BRCA2 carriers. Other genes (CDKN2A, CTNNA1, PALB2, PALLD, PRSS1, SDHC) also showed high similarity but only for a small number of events or for a single event type. Tumors with germline mutations or hypermethylation of BRCA1 had relatively similar gene-expression profiles and overlapped considerably with the Basal-like subtype; but the transcriptional effects of the other events lacked consistency. Our findings confirm previously known relationships between molecular signatures and germline or somatic events in BRCA1/BRCA2. Our methodology represents an objective way to identify genes that have similar downstream effects on molecular signatures when mutated, deleted, or hypermethylated.


Assuntos
Proteína BRCA1/genética , Proteína BRCA2/genética , Neoplasias da Mama/genética , Genes Neoplásicos , Mutação em Linhagem Germinativa , Metilação de DNA , Bases de Dados Genéticas , Feminino , Humanos
9.
Proc Natl Acad Sci U S A ; 116(52): 26798-26807, 2019 Dec 26.
Artigo em Inglês | MEDLINE | ID: mdl-31843900

RESUMO

Mutations responsible for inherited disease may act by disrupting normal transcriptional splicing. Such mutations can be difficult to detect, and their effects difficult to characterize, because many lie deep within exons or introns where they may alter splice enhancers or silencers or introduce new splice acceptors or donors. Multiple mutation-specific and genome-wide approaches have been developed to evaluate these classes of mutations. We introduce a complementary experimental approach, cBROCA, which yields qualitative and quantitative assessments of the effects of genomic mutations on transcriptional splicing of tumor suppressor genes. cBROCA analysis is undertaken by deriving complementary DNA (cDNA) from puromycin-treated patient lymphoblasts, hybridizing the cDNA to the BROCA panel of tumor suppressor genes, and then multiplex sequencing to very high coverage. At each splice junction suggested by split sequencing reads, read depths of test and control samples are compared. Significant Z scores indicate altered transcripts, over and above naturally occurring minor transcripts, and comparisons of read depths indicate relative abundances of mutant and normal transcripts. BROCA analysis of genomic DNA suggested 120 rare mutations from 150 families with cancers of the breast, ovary, uterus, or colon, in >600 informative genotyped relatives. cBROCA analysis of their transcripts revealed a wide variety of consequences of abnormal splicing in tumor suppressor genes, including whole or partial exon skipping, exonification of intronic sequence, loss or gain of exonic and intronic splicing enhancers and silencers, complete intron retention, hypomorphic alleles, and combinations of these alterations. Combined with pedigree analysis, cBROCA sequencing contributes to understanding the clinical consequences of rare inherited mutations.

10.
Clin Transl Gastroenterol ; 10(7): e00054, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-31259752

RESUMO

OBJECTIVES: Loss-of-function mutations of BMPR1A cause juvenile polyposis syndrome (JPS), but large genomic deletions in BMPR1A are rare, reported in few families only, and data regarding the associated phenotype are limited. METHODS: We investigated clinical features and genomic data of 7 extended seemingly unrelated families with a genomic deletion of the entire coding region of BMPR1A. We defined mutation size, mutation prevalence, and tumor pathogenesis using whole-genome sequencing, targeted genotyping, and haplotype analysis. RESULTS: Patients with JPS from 7 families of Bukharin Jewish ancestry carried a deletion of 429 kb, encompassing the BMPR1A coding sequence and 8 downstream genes. Haplotype analysis and testing controls identified this as a common founder mutation occurring in 1/124 individuals of Bukharin origin. Tumor testing did not demonstrate loss of heterozygosity. Among carriers, JPS was almost fully penetrant, but clinical features varied widely, ranging from mild to very severe, including pan-enteric polyps, gastritis, and colorectal, esophageal, and testicular cancer, and carriers with phenotypes, which would not have raised suspicion of JPS. DISCUSSION: The phenotype in this large cohort was extremely variable, although all carriers shared the same variant and the same genetic background. New observations include a preponderance of adenomatous rather than juvenile polyps, possible association with testicular cancer, and unexpected upper gastrointestinal involvement.


Assuntos
Receptores de Proteínas Morfogenéticas Ósseas Tipo I/genética , Gastrite/complicações , Polipose Intestinal/congênito , Síndromes Neoplásicas Hereditárias/genética , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Alelos , Pré-Escolar , Neoplasias Colorretais/complicações , Neoplasias Colorretais/etnologia , Neoplasias Colorretais/genética , Neoplasias Esofágicas/complicações , Neoplasias Esofágicas/etnologia , Neoplasias Esofágicas/genética , Feminino , Gastrite/etnologia , Gastrite/genética , Genoma , Heterozigoto , Humanos , Polipose Intestinal/genética , Pólipos Intestinais/complicações , Pólipos Intestinais/etnologia , Pólipos Intestinais/genética , Pólipos Intestinais/patologia , Israel/etnologia , Judeus/genética , Masculino , Pessoa de Meia-Idade , Linhagem , Fenótipo , Deleção de Sequência/genética , Neoplasias Testiculares/complicações , Neoplasias Testiculares/etnologia , Neoplasias Testiculares/genética , Adulto Jovem
11.
Proc Natl Acad Sci U S A ; 116(18): 9008-9013, 2019 04 30.
Artigo em Inglês | MEDLINE | ID: mdl-30975761

RESUMO

Survival from malignant mesothelioma, particularly pleural mesothelioma, is very poor. For patients with breast, ovarian, or prostate cancers, overall survival is associated with increased sensitivity to platinum chemotherapy due to loss-of-function mutations in DNA repair genes. The goal of this project was to evaluate, in patients with malignant mesothelioma, the relationship between inherited loss-of-function mutations in DNA repair and other tumor suppressor genes and overall survival following platinum chemotherapy. Patients with histologically confirmed malignant mesothelioma were evaluated for inherited mutations in tumor suppressor genes. Survival was evaluated with respect to genotype and site of mesothelioma. Among 385 patients treated with platinum chemotherapy, median overall survival was significantly longer for patients with loss-of-function mutations in any of the targeted genes compared with patients with no such mutation (P = 0.0006). The effect of genotype was highly significant for patients with pleural mesothelioma (median survival 7.9 y versus 2.4 y, P = 0.0012), but not for patients with peritoneal mesothelioma (median survival 8.2 y versus 5.4 y, P = 0.47). Effect of patient genotype on overall survival, measured at 3 y, remained independently significant after adjusting for gender and age at diagnosis, two other known prognostic factors. Patients with pleural mesothelioma with inherited mutations in DNA repair and other tumor suppressor genes appear to particularly benefit from platinum chemotherapy compared with patients without inherited mutations. These patients may also benefit from other DNA repair targeted therapies such as poly-ADP ribose polymerase (PARP) inhibitors.


Assuntos
Mesotelioma/genética , Mesotelioma/mortalidade , Adulto , Idoso , Idoso de 80 Anos ou mais , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Reparo do DNA/genética , Feminino , Predisposição Genética para Doença/genética , Mutação em Linhagem Germinativa , Humanos , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/mortalidade , Masculino , Mesotelioma/tratamento farmacológico , Mesotelioma Maligno , Pessoa de Meia-Idade , Platina/uso terapêutico , Neoplasias Pleurais/genética , Neoplasias Pleurais/mortalidade , Análise de Sobrevida , Proteínas Supressoras de Tumor/genética , Ubiquitina Tiolesterase/genética , Adulto Jovem
12.
Blood ; 134(2): 186-198, 2019 07 11.
Artigo em Inglês | MEDLINE | ID: mdl-31010849

RESUMO

Myeloid neoplasms, including myelodysplastic syndromes (MDS), are genetically heterogeneous disorders driven by clonal acquisition of somatic mutations in hematopoietic stem and progenitor cells (HPCs). The order of premalignant mutations and their impact on HPC self-renewal and differentiation remain poorly understood. We show that episomal reprogramming of MDS patient samples generates induced pluripotent stem cells from single premalignant cells with a partial complement of mutations, directly informing the temporal order of mutations in the individual patient. Reprogramming preferentially captured early subclones with fewer mutations, which were rare among single patient cells. To evaluate the functional impact of clonal evolution in individual patients, we differentiated isogenic MDS induced pluripotent stem cells harboring up to 4 successive clonal abnormalities recapitulating a progressive decrease in hematopoietic differentiation potential. SF3B1, in concert with epigenetic mutations, perturbed mitochondrial function leading to accumulation of damaged mitochondria during disease progression, resulting in apoptosis and ineffective erythropoiesis. Reprogramming also informed the order of premalignant mutations in patients with complex karyotype and identified 5q deletion as an early cytogenetic anomaly. The loss of chromosome 5q cooperated with TP53 mutations to perturb genome stability, promoting acquisition of structural and karyotypic abnormalities. Reprogramming thus enables molecular and functional interrogation of preleukemic clonal evolution, identifying mitochondrial function and chromosome stability as key pathways affected by acquisition of somatic mutations in MDS.


Assuntos
Reprogramação Celular , Evolução Clonal/genética , Células-Tronco Hematopoéticas/patologia , Síndromes Mielodisplásicas/genética , Células-Tronco Pluripotentes/patologia , Humanos
13.
Hum Mol Genet ; 28(1): 133-142, 2019 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-30247636

RESUMO

Severe thrombocytopenia, characterized by dysplastic megakaryocytes and intracranial bleeding, was diagnosed in six individuals from a consanguineous kindred. Three of the individuals were successfully treated by bone marrow transplant. Whole-exome sequencing and homozygosity mapping of multiple family members, coupled with whole-genome sequencing to reveal shared non-coding variants, revealed one potentially functional variant segregating with thrombocytopenia under a recessive model: GALE p.R51W (c.C151T, NM_001127621). The mutation is extremely rare (allele frequency = 2.5 × 10-05), and the likelihood of the observed co-segregation occurring by chance is 1.2 × 10-06. GALE encodes UDP-galactose-4-epimerase, an enzyme of galactose metabolism and glycosylation responsible for two reversible reactions: interconversion of UDP-galactose with UDP-glucose and interconversion of UDP-N-acetylgalactosamine with UDP-N-acetylglucosamine. The mutation alters an amino acid residue that is conserved from yeast to humans. The variant protein has both significantly lower enzymatic activity for both interconversion reactions and highly significant thermal instability. Proper glycosylation is critical to normal hematopoiesis, in particular to megakaryocyte and platelet development, as reflected in the presence of thrombocytopenia in the context of congenital disorders of glycosylation. Mutations in GALE have not previously been associated with thrombocytopenia. Our results suggest that GALE p.R51W is inadequate for normal glycosylation and thereby may impair megakaryocyte and platelet development. If other mutations in GALE are shown to have similar consequences, this gene may be proven to play a critical role in hematopoiesis.


Assuntos
Galactosemias/genética , Trombocitopenia/genética , UDPglucose 4-Epimerase/genética , Adulto , Alelos , Feminino , Galactose/metabolismo , Frequência do Gene/genética , Humanos , Masculino , Pessoa de Meia-Idade , Linhagem , UDPglucose 4-Epimerase/metabolismo , Sequenciamento do Exoma
14.
N Engl J Med ; 379(11): 1042-1049, 2018 09 13.
Artigo em Inglês | MEDLINE | ID: mdl-30207912

RESUMO

The causes of ovarian dysgenesis remain incompletely understood. Two sisters with XX ovarian dysgenesis carried compound heterozygous truncating mutations in the BRCA2 gene that led to reduced BRCA2 protein levels and an impaired response to DNA damage, which resulted in chromosomal breakage and the failure of RAD51 to be recruited to double-stranded DNA breaks. The sisters also had microcephaly, and one sister was in long-term remission from leukemia, which had been diagnosed when she was 5 years old. Drosophila mutants that were null for an orthologue of BRCA2 were sterile, and gonadal dysgenesis was present in both sexes. These results revealed a new role for BRCA2 and highlight the importance to ovarian development of genes that are critical for recombination during meiosis. (Funded by the Israel Science Foundation and others.).


Assuntos
Proteína BRCA2/deficiência , Quebra Cromossômica , Reparo do DNA , Genes BRCA2 , Disgenesia Gonadal/genética , Ovário/crescimento & desenvolvimento , Adolescente , Animais , Proteína BRCA2/fisiologia , Quebra Cromossômica/efeitos dos fármacos , Análise Mutacional de DNA , Drosophila melanogaster , Feminino , Humanos , Hipogonadismo/genética , Masculino , Microcefalia/genética , Mitomicina/farmacologia , Modelos Animais , Ovário/fisiologia , Linhagem , Irmãos , Adulto Jovem
15.
Eur J Hum Genet ; 26(12): 1840-1847, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-30139988

RESUMO

For multiple generations, much of the Arab population of Northern Israel has lived in communities with consanguineous marriages and large families. These communities have been particularly cooperative and informative for understanding the genetics of recessive traits. We studied the genetics of hearing loss in this population, evaluating 168 families from 46 different villages. All families were screened for founder variants by Sanger sequencing and 13 families were further evaluated by sequencing all known genes for hearing loss using our targeted gene panel HEar-Seq. Deafness in 34 of 168 families (20%) was explained by founder variants in GJB2, SLC26A4, or OTOF. In 6 of 13 families (46%) evaluated using HEar-Seq, deafness was explained by damaging alleles of SLC26A4, MYO15A, OTOG, LOXHD1, and TBC1D24. In some genes critical to hearing, it is particularly difficult to interpret variants that might affect splicing, because the genes are not expressed in accessible tissue. To address this problem for possible splice-altering variants of MYO15A, we evaluated minigenes transfected into HEK293 cells. Results revealed exon skipping in the message of MYO15A c.9083+6T>A, and intron retention in the message of MYO15A c.8340G>A, in each case leading to a premature stop and consistent with co-segregation of homozygosity for each variant with hearing loss. The profile of genetics of hearing loss in this population reflects the genetic heterogeneity of hearing loss and the usefulness of synthetic technologies to evaluate potentially causal variants in genes not expressed in accessible tissues.


Assuntos
Árabes/genética , Perda Auditiva/genética , Taxa de Mutação , Proteínas de Transporte/genética , Conexina 26 , Conexinas/genética , Feminino , Proteínas Ativadoras de GTPase , Células HEK293 , Perda Auditiva/epidemiologia , Humanos , Israel , Masculino , Proteínas de Membrana/genética , Miosinas/genética , Proteínas do Tecido Nervoso , Linhagem , Transportadores de Sulfato/genética
16.
J Clin Oncol ; 36(28): 2820-2825, 2018 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-30130155

RESUMO

PURPOSE: Among Nigerian women, breast cancer is diagnosed at later stages, is more frequently triple-negative disease, and is far more frequently fatal than in Europe or the United States. We evaluated the contribution of an inherited predisposition to breast cancer in this population. PATIENTS AND METHODS: Cases were 1,136 women with invasive breast cancer (mean age at diagnosis, 47.5 ± 11.5 years) ascertained in Ibadan, Nigeria. Patients were selected regardless of age at diagnosis, family history, or prior genetic testing. Controls were 997 women without cancer (mean age at interview, 47.0 ± 12.4 years) from the same communities. BROCA panel sequencing was used to identify loss-of-function mutations in known and candidate breast cancer genes. RESULTS: Of 577 patients with information on tumor stage, 86.1% (497) were diagnosed at stage III (241) or IV (256). Of 290 patients with information on tumor hormone receptor status and human epidermal growth factor receptor 2, 45.9% (133) had triple-negative breast cancer. Among all cases, 14.7% (167 of 1,136) carried a loss-of-function mutation in a breast cancer gene: 7.0% in BRCA1, 4.1% in BRCA2, 1.0% in PALB2, 0.4% in TP53, and 2.1% in any of 10 other genes. Odds ratios were 23.4 (95% CI, 7.4 to 73.9) for BRCA1 and 10.3 (95% CI, 3.7 to 28.5) for BRCA2. Risks were also significantly associated with PALB2 (11 cases, zero controls; P = .002) and TP53 (five cases, zero controls; P = .036). Compared with other patients, BRCA1 mutation carriers were younger ( P < .001) and more likely to have triple-negative breast cancer ( P = .028). CONCLUSION: Among Nigerian women, one in eight cases of invasive breast cancer is a result of inherited mutations in BRCA1, BRCA2, PALB2, or TP53, and breast cancer risks associated with these genes are extremely high. Given limited resources, prevention and early detection services should be especially focused on these highest-risk women.


Assuntos
Neoplasias da Mama/epidemiologia , Neoplasias da Mama/genética , Predisposição Genética para Doença , Adulto , Feminino , Humanos , Pessoa de Meia-Idade , Mutação , Nigéria/epidemiologia
18.
Genet Med ; 20(10): 1175-1185, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-29469822

RESUMO

PURPOSE: To characterize the molecular genetics of autosomal recessive Noonan syndrome. METHODS: Families underwent phenotyping for features of Noonan syndrome in children and their parents. Two multiplex families underwent linkage analysis. Exome, genome, or multigene panel sequencing was used to identify variants. The molecular consequences of observed splice variants were evaluated by reverse-transcription polymerase chain reaction. RESULTS: Twelve families with a total of 23 affected children with features of Noonan syndrome were evaluated. The phenotypic range included mildly affected patients, but it was lethal in some, with cardiac disease and leukemia. All of the parents were unaffected. Linkage analysis using a recessive model supported a candidate region in chromosome 22q11, which includes LZTR1, previously shown to harbor mutations in patients with Noonan syndrome inherited in a dominant pattern. Sequencing analyses of 21 live-born patients and a stillbirth identified biallelic pathogenic variants in LZTR1, including putative loss-of-function, missense, and canonical and noncanonical splicing variants in the affected children, with heterozygous, clinically unaffected parents and heterozygous or normal genotypes in unaffected siblings. CONCLUSION: These clinical and genetic data confirm the existence of a form of Noonan syndrome that is inherited in an autosomal recessive pattern and identify biallelic mutations in LZTR1.


Assuntos
Predisposição Genética para Doença , Síndrome de Noonan/genética , Fatores de Transcrição/genética , Adolescente , Criança , Pré-Escolar , Exoma/genética , Feminino , Ligação Genética , Genótipo , Heterozigoto , Humanos , Lactente , Masculino , Mutação , Síndrome de Noonan/patologia , Linhagem , Isoformas de Proteínas/genética , Splicing de RNA/genética , Irmãos
19.
Clin Cancer Res ; 24(4): 777-783, 2018 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-29191972

RESUMO

Purpose: We hypothesized that mutations in homologous recombination repair (HRR) genes beyond BRCA1 and BRCA2 improve outcomes for ovarian carcinoma patients treated with platinum therapy and would impact the relative benefit of adding prolonged bevacizumab.Experimental Design: We sequenced DNA from blood and/or neoplasm from 1,195 women enrolled in GOG-0218, a randomized phase III trial in advanced ovarian carcinoma of bevacizumab added to carboplatin and paclitaxel. Defects in HRR were defined as damaging mutations in 16 genes. Proportional hazards models were used to estimate relative hazards for progression-free survival (PFS) and overall survival (OS).Results: Of 1,195 women with ovarian carcinoma, HRR mutations were identified in 307 (25.7%). Adjusted hazards for progression and death compared with those without mutations were lower for women with non-BRCA HRR mutations [HR = 0.73; 95% confidence interval (CI), 0.57-0.94; P = 0.01 for PFS; HR = 0.67; 95% CI, 0.50-0.90; P = 0.007 for OS] and BRCA1 mutations (HR = 0.80; 95% CI, 0.66-0.97; P = 0.02 for PFS; HR = 0.74; 95% CI, 0.59-0.94; P = 0.01 for OS) and were lowest for BRCA2 mutations (HR = 0.52; 95% CI, 0.40-0.67; P < 0.0001 for PFS; HR = 0.36; 95% CI, 0.25-0.53; P < 0.0001 for OS). A test of interaction showed no difference in the effect of bevacizumab on PFS between cases with and without mutations.Conclusions: HRR mutations, including non-BRCA genes, significantly prolong PFS and OS in ovarian carcinoma and should be stratified for in clinical trials. The benefit of adding bevacizumab was not significantly modified by mutation status. Clin Cancer Res; 24(4); 777-83. ©2017 AACR.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Variações do Número de Cópias de DNA , Mutação , Neoplasias Ovarianas/tratamento farmacológico , Reparo de DNA por Recombinação/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Bevacizumab/administração & dosagem , Carboplatina/administração & dosagem , Feminino , Humanos , Estimativa de Kaplan-Meier , Pessoa de Meia-Idade , Avaliação de Resultados em Cuidados de Saúde/métodos , Avaliação de Resultados em Cuidados de Saúde/estatística & dados numéricos , Neoplasias Ovarianas/sangue , Neoplasias Ovarianas/genética , Paclitaxel/administração & dosagem , Modelos de Riscos Proporcionais
20.
JAMA Oncol ; 3(12): 1647-1653, 2017 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-28727877

RESUMO

Importance: Among Ashkenazi Jewish women, 3 mutations in BRCA1 and BRCA2 severely increase the risk of breast and ovarian cancer. However, among Ashkenazi Jewish patients with breast cancer who do not carry one of these founder mutations, the likelihood of carrying another pathogenic mutation in BRCA1 or BRCA2 or another breast cancer gene is not known. This information would be valuable to the patient and family for cancer prevention and treatment. Objective: To determine the frequency of cancer-predisposing mutations other than the BRCA1 and BRCA2 founder alleles among patients of Ashkenazi Jewish ancestry with breast cancer. Design, Setting, and Participants: In this cohort study, genomic DNA of women from 12 major cancer centers with a first diagnosis of invasive breast cancer who identified themselves and all 4 grandparents as Ashkenazi Jewish and participated in the New York Breast Cancer Study (NYBCS) from 1996 to 2000 was sequenced for known and candidate breast cancer genes. Data analysis was performed from July 10, 2014, to March 10, 2017. Main Outcomes and Measures: Genomic DNA from all 1007 NYBCS probands was sequenced for 23 known and candidate breast cancer genes using BROCA, a targeted multiplexed gene panel. Results: Of the 1007 probands in the study, 903 probands had no founder mutations in BRCA1 or BRCA2; of these probands, 7 (0.8%) carried another pathogenic mutation in BRCA1 or BRCA2, and 31 (3.4%) carried a pathogenic mutation in another breast cancer gene (29 in CHEK2, and 1 each in BRIP1 and NBN). Of all inherited predispositions to breast cancer in the NYBCS, 73.8% (104 of 142) were due to a BRCA1 or BRCA2 founder allele, 4.9% (7 of 142) to another BRCA1 or BRCA2 mutation, and 21.8% (31 of 142) to a mutation in another gene. Overall, 14.1% (142 of 1007) of Ashkenazi Jewish patients with breast cancer in the NYBCS carried a germline mutation responsible for their disease: 11.0% (111 of 1007) in BRCA1 or BRCA2, and 3.1% (31 of 1007) in CHEK2 or another breast cancer gene. Of the 111 patients with BRCA1 or BRCA2 mutations, 57 (51.4%) had a mother or sister with breast or ovarian cancer and 54 patients (48.6%) did not. Conclusions and Relevance: Comprehensive sequencing would provide complete relevant genetic information for Ashkenazi Jewish patients with breast cancer.


Assuntos
Neoplasias da Mama/genética , Testes Genéticos/métodos , Judeus/genética , Mutação , Análise de Sequência de DNA/métodos , Adulto , Idoso , Proteína BRCA1/genética , Proteína BRCA2/genética , Neoplasias da Mama/etnologia , Proteínas de Ciclo Celular/genética , Quinase do Ponto de Checagem 2/genética , Estudos de Coortes , Proteínas de Grupos de Complementação da Anemia de Fanconi/genética , Feminino , Efeito Fundador , Frequência do Gene , Predisposição Genética para Doença , Avós , Humanos , Pessoa de Meia-Idade , Proteínas Nucleares/genética , Linhagem , RNA Helicases/genética
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