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1.
Microbiol Spectr ; 10(3): e0103221, 2022 06 29.
Artigo em Inglês | MEDLINE | ID: mdl-35499325

RESUMO

This study includes 259 consecutive nasopharyngeal swabs which tested positive for a molecular SARS-CoV-2 test and 77 subjects who were followed longitudinally, with nasopharyngeal swabs performed weekly until clinical recovery and a negative result for the molecular test were reached. All swabs were also tested with a Lumipulse SARS-CoV-2 chemiluminescence enzyme immunoassay (CLEIA) antigen assay. The antigen test was positive in 169 (65.3%) out of the 259 subjects, while no antigen was detected in 90 subjects (34.7%). In the antigen-positive subjects, clinical status moved slightly toward a more frequent presence of symptoms. Longitudinal follow-up shows how the time of negativization has a faster kinetic in the antigenic test than in the molecular test. Antigenic test result values, considered as a time-dependent covariate and log-transformed, were highly associated with the time to negative swab, with good prediction ability. Receiver operating characteristic (ROC) curve analysis showed a very good discrimination ability of antigenic tests in classifying negative swabs. The optimal cutoff which jointly maximized sensitivity and specificity was 1.55, resulting in an overall accuracy of 0.75, a sensitivity of 0.73, and a specificity of 0.83. After dichotomizing the antigenic test according to the previously determined cutoff value of 1.55, the time-dependent covariate Cox model again suggests a highly significant association of antigenic test values with the time to negative swab molecular: a subject with an antigenic test value lower than 1.55 had almost a 13-fold higher probability to also result negative in the molecular test compared to a subject with an antigenic test value higher than 1.55. IMPORTANCE Our work explores the possibility of using a sensible and reliable antigenic test in a wider range of SARS-CoV-2 diagnostic and clinical applications. Furthermore, this tool seems particularly promising in follow-up with infected subjects, because while the molecular test frequently yields the persistence of low positivities, raising yet unanswered questions, this antigenic test shows more uniform and faster negativization during the evolution of the infection, somehow paralleling the dynamics of infectivity. Although more data will be required to definitely prove it, we believe these findings might be of great interest.


Assuntos
COVID-19 , SARS-CoV-2 , COVID-19/diagnóstico , Seguimentos , Humanos , Técnicas Imunoenzimáticas , Luminescência , SARS-CoV-2/genética
2.
J Neurooncol ; 137(1): 33-38, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29230670

RESUMO

In sporadic schwannomas, inactivation of both copies of the NF2 tumor suppressor gene on 22q is common. Constitutional mutations of SMARCB1 are responsible of schwannomatosis, an inherited tumor predisposition syndrome, characterized by the development of multiple schwannomas. We analysed the frequency of copy number changes on chromosome 22 and the mutation of NF2 and SMARCB1 in 26 sporadic schwannomas. We found two spinal schwannomas with an identical somatic missense mutation in SMARCB1 exon 9: p.(Arg377His). Both SMARCB1 mutated schwannomas had LOH of 22q and one of them harbored an inactivating mutation of NF2. The p.(Arg377His) change was not found in a series of 28 vestibular schwannomas. Our data indicate that mutations affecting SMARCB1 play a role in the development or progression of a small subset of spinal schwannomas and that biallelic inactivation of SMARCB1 may cooperate with deficiency of NF2 function in schwannoma tumorigenesis according to the "four-hit/three events" mechanism of tumorigenesis that we demonstrated in schwannomatosis-associated schwannomas.


Assuntos
Neurilemoma/genética , Neurofibromina 2/genética , Proteína SMARCB1/genética , Neoplasias da Coluna Vertebral/genética , Adulto , Idoso , Criança , Cromossomos Humanos Par 22/genética , Feminino , Predisposição Genética para Doença , Humanos , Masculino , Pessoa de Meia-Idade , Mutação , Neuroma Acústico/genética , Adulto Jovem
3.
J Mol Diagn ; 20(1): 87-94, 2018 01.
Artigo em Inglês | MEDLINE | ID: mdl-29061375

RESUMO

The efficiency of a novel targeted next-generation sequencing (NGS) test, the Devyser BRCA kit, for a comprehensive analysis of all 48 coding exons of the high-risk breast/ovarian cancer susceptibility genes BRCA1 and BRCA2 has been assessed. The new assay intended to detect nucleotide substitutions, small deletions/insertions, and large deletions/duplications. To document the false-negative and false-positive rates of the NGS assay in the hands of end users, 48 samples with previously identified 444 small variants and seven gross rearrangements were analyzed, showing 100% concordance with gold standards. Furthermore, all other 43 variants (42 single-nucleotide variation or insertion/deletion variation and one copy number variation, whose significance is or may be of clinical value), which were called by the NGS assay in a prospectively analyzed 179-sample set, were confirmed by Sanger sequencing or multiplex ligation probe amplification, according to their nature. We conclude that the Devyser BRCA kit performed satisfactorily for use in a clinical laboratory.


Assuntos
Proteína BRCA1/genética , Proteína BRCA2/genética , Sequenciamento de Nucleotídeos em Larga Escala/métodos , Mutação/genética , Variações do Número de Cópias de DNA/genética , Éxons/genética , Humanos , Polimorfismo de Nucleotídeo Único/genética , Reprodutibilidade dos Testes
4.
Hum Mol Genet ; 24(18): 5345-55, 2015 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-26130695

RESUMO

Numerous genetic factors that influence breast cancer risk are known. However, approximately two-thirds of the overall familial risk remain unexplained. To determine whether some of the missing heritability is due to rare variants conferring high to moderate risk, we tested for an association between the c.5791C>T nonsense mutation (p.Arg1931*; rs144567652) in exon 22 of FANCM gene and breast cancer. An analysis of genotyping data from 8635 familial breast cancer cases and 6625 controls from different countries yielded an association between the c.5791C>T mutation and breast cancer risk [odds ratio (OR) = 3.93 (95% confidence interval (CI) = 1.28-12.11; P = 0.017)]. Moreover, we performed two meta-analyses of studies from countries with carriers in both cases and controls and of all available data. These analyses showed breast cancer associations with OR = 3.67 (95% CI = 1.04-12.87; P = 0.043) and OR = 3.33 (95% CI = 1.09-13.62; P = 0.032), respectively. Based on information theory-based prediction, we established that the mutation caused an out-of-frame deletion of exon 22, due to the creation of a binding site for the pre-mRNA processing protein hnRNP A1. Furthermore, genetic complementation analyses showed that the mutation influenced the DNA repair activity of the FANCM protein. In summary, we provide evidence for the first time showing that the common p.Arg1931* loss-of-function variant in FANCM is a risk factor for familial breast cancer.


Assuntos
Processamento Alternativo , Códon sem Sentido , DNA Helicases/genética , Reparo do DNA , Éxons , Adulto , Idade de Início , Alelos , Sítios de Ligação , Neoplasias da Mama/epidemiologia , Neoplasias da Mama/genética , Estudos de Casos e Controles , DNA Helicases/metabolismo , Análise Mutacional de DNA , Feminino , Expressão Gênica , Frequência do Gene , Estudos de Associação Genética , Predisposição Genética para Doença , Genótipo , Ribonucleoproteína Nuclear Heterogênea A1 , Ribonucleoproteínas Nucleares Heterogêneas Grupo A-B/metabolismo , Humanos , Metanálise como Assunto , Pessoa de Meia-Idade , Motivos de Nucleotídeos , Matrizes de Pontuação de Posição Específica , Ligação Proteica , Fatores de Risco , Adulto Jovem
5.
Cell Transplant ; 24(5): 811-7, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-24380491

RESUMO

Fetal grafting in a human diseased brain was thought to be less immunogenic than other solid organ transplants, hence the minor impact on the efficacy of the transplant. How much prophylactic immune protection is required for neural allotransplantation is also debated. High-sensitive anti-HLA antibody screening in this field has never been reported. Sixteen patients with Huntington's disease underwent human fetal striatal transplantation in the frame of an open-label observational trial, which is being carried out at Florence University. All patients had both brain hemispheres grafted in two separate robotic-stereotactic procedures. The trial started in February 2006 with the first graft to the first patient (R1). R16 was given his second graft on March 2011. All patients received triple immunosuppressive treatment. Pre- and posttransplant sera were analyzed for the presence of anti-HLA antibodies using the multiplexed microsphere-based suspension array Luminex xMAP technology. Median follow-up was 38.5 months (range 13-85). Six patients developed anti-HLA antibodies, which turned out to be donor specific. Alloimmunization occurred in a time window of 0-49 months after the first neurosurgical procedure. The immunogenic determinants were non-self-epitopes from mismatched HLA antigens. These determinants were both public epitopes shared by two or more HLA molecules and private epitopes unique to individual HLA molecules. One patient had non-donor-specific anti-HLA antibodies in her pretransplant serum sample, possibly due to previous sensitization events. Although the clinical significance of donor-specific antibodies is far from being established, particularly in the setting of neuronal transplantation, these findings underline the need of careful pre- and posttransplant immunogenetic evaluation of patients with intracerebral grafts.


Assuntos
Corpo Estriado/transplante , Antígenos HLA , Doença de Huntington/sangue , Doença de Huntington/cirurgia , Isoanticorpos/sangue , Aloenxertos , Feminino , Feto , Humanos , Masculino , Fatores de Tempo
6.
PLoS One ; 9(2): e86924, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24516540

RESUMO

The identification of founder mutations in cancer predisposing genes is important to improve risk assessment in geographically defined populations, since it may provide specific targets resulting in cost-effective genetic testing. Here, we report the characterization of the BRCA1 c.190T>C (p.Cys64Arg) mutation, mapped to the RING-finger domain coding region, that we detected in 43 hereditary breast/ovarian cancer (HBOC) families, for the large part originating from the province of Bergamo (Northern Italy). Haplotype analysis was performed in 21 families, and led to the identification of a shared haplotype extending over three BRCA1-associated marker loci (0.4 cM). Using the DMLE+2.2 software program and regional population demographic data, we were able to estimate the age of the mutation to vary between 3,100 and 3,350 years old. Functional characterization of the mutation was carried out at both transcript and protein level. Reverse transcriptase-PCR analysis on lymphoblastoid cells revealed expression of full length mRNA from the mutant allele. A green fluorescent protein (GFP)-fragment reassembly assay showed that the p.Cys64Arg substitution prevents the binding of the BRCA1 protein to the interacting protein BARD1, in a similar way as proven deleterious mutations in the RING-domain. Overall, 55 of 83 (66%) female mutation carriers had a diagnosis of breast and/or ovarian cancer. Our observations indicate that the BRCA1 c.190T>C is a pathogenic founder mutation present in the Italian population. Further analyses will evaluate whether screening for this mutation can be suggested as an effective strategy for the rapid identification of at-risk individuals in the Bergamo area.


Assuntos
Proteína BRCA1/química , Proteína BRCA1/genética , Efeito Fundador , Predisposição Genética para Doença , Mutação/genética , Adulto , Fatores Etários , Neoplasias da Mama/genética , Neoplasias da Mama/patologia , Segregação de Cromossomos/genética , Éxons/genética , Família , Feminino , Regulação Neoplásica da Expressão Gênica , Geografia , Proteínas de Fluorescência Verde/metabolismo , Haplótipos/genética , Humanos , Itália , Pessoa de Meia-Idade , Taxa de Mutação , Neoplasias Ovarianas/genética , Neoplasias Ovarianas/patologia , Ligação Proteica , Isoformas de Proteínas/genética , Isoformas de Proteínas/metabolismo , Domínios RING Finger , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Proteínas Supressoras de Tumor/metabolismo , Ubiquitina-Proteína Ligases/metabolismo
7.
Cancer Epidemiol Biomarkers Prev ; 21(1): 134-47, 2012 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-22144499

RESUMO

BACKGROUND: Previously, small studies have found that BRCA1 and BRCA2 breast tumors differ in their pathology. Analysis of larger datasets of mutation carriers should allow further tumor characterization. METHODS: We used data from 4,325 BRCA1 and 2,568 BRCA2 mutation carriers to analyze the pathology of invasive breast, ovarian, and contralateral breast cancers. RESULTS: There was strong evidence that the proportion of estrogen receptor (ER)-negative breast tumors decreased with age at diagnosis among BRCA1 (P-trend = 1.2 × 10(-5)), but increased with age at diagnosis among BRCA2, carriers (P-trend = 6.8 × 10(-6)). The proportion of triple-negative tumors decreased with age at diagnosis in BRCA1 carriers but increased with age at diagnosis of BRCA2 carriers. In both BRCA1 and BRCA2 carriers, ER-negative tumors were of higher histologic grade than ER-positive tumors (grade 3 vs. grade 1; P = 1.2 × 10(-13) for BRCA1 and P = 0.001 for BRCA2). ER and progesterone receptor (PR) expression were independently associated with mutation carrier status [ER-positive odds ratio (OR) for BRCA2 = 9.4, 95% CI: 7.0-12.6 and PR-positive OR = 1.7, 95% CI: 1.3-2.3, under joint analysis]. Lobular tumors were more likely to be BRCA2-related (OR for BRCA2 = 3.3, 95% CI: 2.4-4.4; P = 4.4 × 10(-14)), and medullary tumors BRCA1-related (OR for BRCA2 = 0.25, 95% CI: 0.18-0.35; P = 2.3 × 10(-15)). ER-status of the first breast cancer was predictive of ER-status of asynchronous contralateral breast cancer (P = 0.0004 for BRCA1; P = 0.002 for BRCA2). There were no significant differences in ovarian cancer morphology between BRCA1 and BRCA2 carriers (serous: 67%; mucinous: 1%; endometrioid: 12%; clear-cell: 2%). CONCLUSIONS/IMPACT: Pathologic characteristics of BRCA1 and BRCA2 tumors may be useful for improving risk-prediction algorithms and informing clinical strategies for screening and prophylaxis.


Assuntos
Neoplasias da Mama/genética , Neoplasias da Mama/patologia , Genes BRCA1 , Genes BRCA2 , Neoplasias Ovarianas/genética , Neoplasias Ovarianas/patologia , Adulto , Idoso , Feminino , Predisposição Genética para Doença , Mutação em Linhagem Germinativa , Humanos , Pessoa de Meia-Idade , Gradação de Tumores
8.
Hum Mol Genet ; 20(16): 3304-21, 2011 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-21593217

RESUMO

Two single nucleotide polymorphisms (SNPs) at 6q25.1, near the ESR1 gene, have been implicated in the susceptibility to breast cancer for Asian (rs2046210) and European women (rs9397435). A genome-wide association study in Europeans identified two further breast cancer susceptibility variants: rs11249433 at 1p11.2 and rs999737 in RAD51L1 at 14q24.1. Although previously identified breast cancer susceptibility variants have been shown to be associated with breast cancer risk for BRCA1 and BRCA2 mutation carriers, the involvement of these SNPs to breast cancer susceptibility in mutation carriers is currently unknown. To address this, we genotyped these SNPs in BRCA1 and BRCA2 mutation carriers from 42 studies from the Consortium of Investigators of Modifiers of BRCA1/2. In the analysis of 14 123 BRCA1 and 8053 BRCA2 mutation carriers of European ancestry, the 6q25.1 SNPs (r(2) = 0.14) were independently associated with the risk of breast cancer for BRCA1 mutation carriers [hazard ratio (HR) = 1.17, 95% confidence interval (CI): 1.11-1.23, P-trend = 4.5 × 10(-9) for rs2046210; HR = 1.28, 95% CI: 1.18-1.40, P-trend = 1.3 × 10(-8) for rs9397435], but only rs9397435 was associated with the risk for BRCA2 carriers (HR = 1.14, 95% CI: 1.01-1.28, P-trend = 0.031). SNP rs11249433 (1p11.2) was associated with the risk of breast cancer for BRCA2 mutation carriers (HR = 1.09, 95% CI: 1.02-1.17, P-trend = 0.015), but was not associated with breast cancer risk for BRCA1 mutation carriers (HR = 0.97, 95% CI: 0.92-1.02, P-trend = 0.20). SNP rs999737 (RAD51L1) was not associated with breast cancer risk for either BRCA1 or BRCA2 mutation carriers (P-trend = 0.27 and 0.30, respectively). The identification of SNPs at 6q25.1 associated with breast cancer risk for BRCA1 mutation carriers will lead to a better understanding of the biology of tumour development in these women.


Assuntos
Alelos , Proteína BRCA1/genética , Proteína BRCA2/genética , Neoplasias da Mama/genética , Cromossomos Humanos/genética , Predisposição Genética para Doença , Mutação/genética , Adulto , Idoso , Cromossomos Humanos Par 1/genética , Cromossomos Humanos Par 6/genética , Feminino , Heterozigoto , Humanos , Pessoa de Meia-Idade , Polimorfismo de Nucleotídeo Único/genética , Fatores de Risco
9.
Pharmacol Res ; 64(3): 242-8, 2011 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-21536130

RESUMO

BACKGROUND AND OBJECTIVES: Thymidylate synthase (TS) expression levels appear to be related to response to 5-fluorouracil-(5-FU)-based chemotherapy in colorectal cancer (CRC) patients. Three polymorphisms have been proposed as modulators of TS expression: a tandemly repeated sequence (2R/3R) in the 5' UTR, a SNP (G>C) within the 3R allele and a 6bp deletion in the 3' UTR. To evaluate the influence of TS expression and polymorphisms on clinical outcome of 5-FU-treated patients we performed a comprehensive genetic analysis on 63 CRC patients. METHODS: TS expression levels were analyzed in normal and tumor tissues. TS coding sequence and UTR polymorphisms were investigated on DNA from normal tissue. LOH analysis was performed to determine tumor genotype. RESULTS: A difference in disease-free survival (DFS), although not statistically significant, was observed between high and low mRNA expression levels: patients with low levels showed longer DFS. The 2R2R genotype showed significantly lower expression than the 3R3R and 2R3R genotypes in normal tissue. No other TS polymorphism was associated with mRNA expression or clinical outcome. CONCLUSIONS: The results obtained in this pilot study indicate that the number of 5' UTR repeats is the major genetic determinant of TS expression. The lack of association with other polymorphisms might be partially explained by the existence of linkage disequilibrium in the TS gene. Our data support the growing evidence that TS control may require multiple mechanisms acting in close coordination with one another and suggest that TS genotyping alone in tumor samples is not sufficient to accurately predict response to 5-FU.


Assuntos
Antimetabólitos Antineoplásicos/uso terapêutico , Neoplasias Colorretais/tratamento farmacológico , Neoplasias Colorretais/enzimologia , Fluoruracila/uso terapêutico , Regulação Neoplásica da Expressão Gênica , Timidilato Sintase/genética , Adulto , Idoso , Neoplasias Colorretais/genética , Intervalo Livre de Doença , Feminino , Genótipo , Humanos , Masculino , Pessoa de Meia-Idade , Adulto Jovem
10.
Breast Cancer Res ; 13(2): R40, 2011 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-21466675

RESUMO

INTRODUCTION: Proteins encoded by Fanconi anemia (FA) and/or breast cancer (BrCa) susceptibility genes cooperate in a common DNA damage repair signaling pathway. To gain deeper insight into this pathway and its influence on cancer risk, we searched for novel components through protein physical interaction screens. METHODS: Protein physical interactions were screened using the yeast two-hybrid system. Co-affinity purifications and endogenous co-immunoprecipitation assays were performed to corroborate interactions. Biochemical and functional assays in human, mouse and Caenorhabditis elegans models were carried out to characterize pathway components. Thirteen FANCD2-monoubiquitinylation-positive FA cell lines excluded for genetic defects in the downstream pathway components and 300 familial BrCa patients negative for BRCA1/2 mutations were analyzed for genetic mutations. Common genetic variants were genotyped in 9,573 BRCA1/2 mutation carriers for associations with BrCa risk. RESULTS: A previously identified co-purifying protein with PALB2 was identified, MRG15 (MORF4L1 gene). Results in human, mouse and C. elegans models delineate molecular and functional relationships with BRCA2, PALB2, RAD51 and RPA1 that suggest a role for MRG15 in the repair of DNA double-strand breaks. Mrg15-deficient murine embryonic fibroblasts showed moderate sensitivity to γ-irradiation relative to controls and reduced formation of Rad51 nuclear foci. Examination of mutants of MRG15 and BRCA2 C. elegans orthologs revealed phenocopy by accumulation of RPA-1 (human RPA1) nuclear foci and aberrant chromosomal compactions in meiotic cells. However, no alterations or mutations were identified for MRG15/MORF4L1 in unclassified FA patients and BrCa familial cases. Finally, no significant associations between common MORF4L1 variants and BrCa risk for BRCA1 or BRCA2 mutation carriers were identified: rs7164529, Ptrend = 0.45 and 0.05, P2df = 0.51 and 0.14, respectively; and rs10519219, Ptrend = 0.92 and 0.72, P2df = 0.76 and 0.07, respectively. CONCLUSIONS: While the present study expands on the role of MRG15 in the control of genomic stability, weak associations cannot be ruled out for potential low-penetrance variants at MORF4L1 and BrCa risk among BRCA2 mutation carriers.


Assuntos
Neoplasias da Mama/genética , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Animais , Neoplasias da Mama/metabolismo , Caenorhabditis elegans , Linhagem Celular , Dano ao DNA , Reparo do DNA , Anemia de Fanconi/genética , Proteína do Grupo de Complementação D2 da Anemia de Fanconi/genética , Proteína do Grupo de Complementação D2 da Anemia de Fanconi/metabolismo , Proteína do Grupo de Complementação N da Anemia de Fanconi , Feminino , Genes BRCA1 , Genes BRCA2 , Predisposição Genética para Doença , Humanos , Camundongos , Mutação , Proteínas Nucleares/genética , Proteínas Nucleares/metabolismo , Interferência de RNA , Rad51 Recombinase/genética , Rad51 Recombinase/metabolismo , Proteína de Replicação A/genética , Proteína de Replicação A/metabolismo , Fatores de Risco , Proteínas Supressoras de Tumor/genética , Proteínas Supressoras de Tumor/metabolismo , Técnicas do Sistema de Duplo-Híbrido
11.
Fam Cancer ; 9(2): 181-5, 2010 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-19763884

RESUMO

Recently, it has been demonstrated that monoallelic PALB2 mutations predispose to familial breast cancer. We investigated the contribution of PALB2 mutations in a set of 132 Italian BRCA1/BRCA2-negative breast cancer families; one truncating PALB2 mutation, c.2257C>T, resulting in p.Arg753X, was identified in a woman and her daughter, with breast cancer diagnosed at 60 and 31 years old, respectively. This study supports the recent observation that PALB2 mutation are present, although infrequently, in familial BRCA1/BRCA2-negative breast cancer cases; moreover, it sustains latest evidences that some PALB2 mutations are associated with a substantially increased risk of breast cancer.


Assuntos
Neoplasias da Mama/genética , Predisposição Genética para Doença/genética , Mutação em Linhagem Germinativa/genética , Proteínas Nucleares/genética , Proteínas Supressoras de Tumor/genética , Idade de Início , Proteína BRCA2/genética , Biomarcadores Tumorais , Neoplasias da Mama/epidemiologia , Proteína do Grupo de Complementação N da Anemia de Fanconi , Feminino , Humanos , Itália/epidemiologia , Masculino , Mutação , Linhagem , Proteínas Supressoras de Tumor/metabolismo
12.
Cancer Genet Cytogenet ; 195(1): 75-9, 2009 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-19837273

RESUMO

The simultaneous occurrence of mutations in two different tumor suppressor genes in the same individual is a very rare event. Here we report the case of a woman in whom germline mutations in both MEN1 and BRCA1 were identified. The severity of MEN1-related biochemical and clinical findings did not significantly differ from that for other affected family members lacking the BRCA1 mutation, except for the development of an extremely large visceral lipoma; the proband has not developed any BRCA1-related malignancies. We explore genetic and molecular rationales for an association between these neoplastic processes.


Assuntos
Neoplasias da Mama/genética , Genes BRCA1 , Mutação em Linhagem Germinativa , Neoplasia Endócrina Múltipla Tipo 1/genética , Neoplasias Ovarianas/genética , Proteínas Proto-Oncogênicas/genética , Adulto , Feminino , Humanos
13.
Breast Cancer Res Treat ; 117(3): 497-504, 2009 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-18821011

RESUMO

BACKGROUND: Germline mutations in the BRCA1 and BRCA2 tumour-suppressor genes predispose to early-onset breast and ovarian cancer. Although both genes display a highly heterogeneous mutation spectrum, a number of alterations recur in some populations. Only a limited number of founder mutations have been identified in the Italian population so far. OBJECTIVE: To investigate the spectrum of BRCA1/BRCA2 mutations in a set of families originary from the Central-Eastern part of Tuscany and to ascertain the presence of founder effects. We also wanted to approximate the age of the most frequent BRCA1 founder mutation. RESULTS: Overall, four distinct BRCA1 mutations accounted for a large fraction (72.7%) of BRCA1-attributable hereditary breast/ovarian cancer in families originary from this area. We identified common haplotypes for two newly recognised recurrent BRCA1 mutations, c.3228_3229delAG and c.3285delA. The c.3228_3229delAG mutation was estimated to have originated about 129 generations ago. Interestingly, male breast cancer cases were present in 3 out of 11 families with the c.3228_3229delAG mutation. CONCLUSIONS: The observation that a high proportion of families with BRCA1 alterations from Central-Eastern Tuscany harbours a limited number of founder mutations can have significant impact on clinical management of at risk subjects from this area. In addition, the identification of a large set of families carrying an identical mutation that predisposes to breast and ovarian cancer provides unique opportunities to study the effect of other genetic and environmental factors on penetrance and disease phenotype.


Assuntos
Neoplasias da Mama Masculina/genética , Neoplasias da Mama/genética , Efeito Fundador , Adulto , Idoso , Análise Mutacional de DNA , Feminino , Genes BRCA1 , Haplótipos , Humanos , Itália , Masculino , Repetições de Microssatélites/genética , Pessoa de Meia-Idade , Linhagem
14.
Neurosci Lett ; 446(2-3): 139-42, 2008 Dec 03.
Artigo em Inglês | MEDLINE | ID: mdl-18834925

RESUMO

Tumor necrosis factor-alpha (TNF-alpha) is a pro-inflammatory cytokine that plays an important role in the inflammatory process that can be observed in Alzheimer's disease (AD) brain. Different functional promoter polymorphisms within genes modulating inflammation have been demonstrated to elevate the AD risk; thus, we studied five common variations within the promoter region of the TNF-alpha gene in 609 subjects (253 AD patients and 356 controls). No positive associations were found, confirming the greater part of previous studies. Moreover, we also investigated the combined haplotypes of the five different polymorphisms without finding a positive association. Thus, the present investigation does not support the proposal that common nucleotide variations in the TNF-alpha gene can influence the development of AD at least in Italian population.


Assuntos
Doença de Alzheimer/genética , Química Encefálica/genética , Encéfalo/metabolismo , Predisposição Genética para Doença/genética , Polimorfismo Genético/genética , Fator de Necrose Tumoral alfa/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Encéfalo/fisiopatologia , Estudos de Coortes , Análise Mutacional de DNA , Feminino , Frequência do Gene/genética , Marcadores Genéticos/genética , Testes Genéticos , Variação Genética/genética , Genótipo , Haplótipos/genética , Humanos , Itália , Masculino , Pessoa de Meia-Idade , Mutação/genética , Regiões Promotoras Genéticas/genética
15.
Genet Test ; 9(1): 14-9, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-15857181

RESUMO

Neurofibromatosis type 2 (NF2) is an autosomal dominant disorder that predisposes to the development of bilateral vestibular schwannomas (sometimes associated with schwannomas at other locations), meningiomas, and ependymomas. Point mutations that inactivate the NF2 tumor suppressor gene, located in 22q12, have been found in 45-85% of NF2 patients; in addition, large genomic deletions can be found. To evaluate the presence of genomic NF2 rearrangements, we have developed a fluorescent semiquantitative multiplex PCR method. Briefly, short fragments corresponding to the 17 exons, the promoter region, and the 3' end of the NF2 gene were co-amplified by PCR using dye primers. An additional fragment, corresponding to another gene used as an internal control, was systematically amplified in each multiplex PCR. Initially, we validated the method by using monosomic 22q and trisomic 22 samples. The fluorescent multiplex PCR method was then used to analyze 21 NF2 individuals in which single-strand conformational polymorphism (SSCP) analysis and/or direct sequencing had revealed no NF2 point mutations; we were able to detect two deletions and one duplication in NF2 in 3 patients. In conclusion, the method we developed could easily be applied in detecting NF2 deletions and duplications. Discovering genomic duplications is invaluable because they are probably the most difficult molecular alterations to detect with conventional methods and, as a consequence, might be an underestimated cause of NF2.


Assuntos
Rearranjo Gênico , Genes da Neurofibromatose 2 , Reação em Cadeia da Polimerase/métodos , Sequência de Bases , Primers do DNA , Fluorescência , Humanos
16.
Inflamm Bowel Dis ; 10(6): 705-8, 2004 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-15626886

RESUMO

The hMLH1 gene lies in the linkage susceptibility region to inflammatory bowel disease (IBD) on 3p21. A single nucleotide polymorphism, 655A>G, in exon 8 of the gene causes an I219V change in the MLH1 protein. To test whether hMLH1 may confer susceptibility to ulcerative colitis (UC), we investigated an association between the 655A>G polymorphism and the disease. DNA-based technologies were used to analyze the 655A>G polymorphism in 201 UC patients and 126 healthy ethnically matched controls. The comparison of the allelic frequencies of the 655A>G polymorphism in UC patients and healthy controls did not show significant differences. However, genotype frequencies at the hMLH1 655 position were found to be significantly different when patients with and without refractory UC were compared. This was mainly attributable to a higher level of homozygosity for the G allele in refractory UC patients. Almost 5 times as many (4.9 times) refractory UC patients carried the GG genotype compared with nonrefractory patients (P < 0.0001). The present study provides evidence that the hMLH1 gene is involved in genetic susceptibility to refractory UC. If confirmed by other studies, the GG genotype at position 655 of the hMLH1 gene may represent a useful predictive factor for the clinical management of UC patients.


Assuntos
Colite Ulcerativa/genética , Predisposição Genética para Doença , Proteínas de Neoplasias/genética , Proteínas Adaptadoras de Transdução de Sinal , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Proteínas de Transporte , Estudos de Casos e Controles , Feminino , Genótipo , Humanos , Itália , Masculino , Pessoa de Meia-Idade , Proteína 1 Homóloga a MutL , Mutação , Proteínas Nucleares , Polimorfismo Genético , Recidiva , População Branca/genética
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