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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
221

Taking a Step Back to Make a Leap Forward: A Qualitative Survey of Underrepresented Minority Genetic Counselors

Raymond, Victoria M. 13 July 2006 (has links)
No description available.
222

Tools and Strategies That a BRCA Positive Population Considers to be Useful in the Result Disclosure Process to Family Members

Snyder, Justine A., B.A. 24 September 2012 (has links)
No description available.
223

Factors predicting <i>BRCA1</i> and <i>BRCA2</i> mutation carriers’ preference for communication of risk estimates.

Crowdes, Sophie Rose 12 September 2016 (has links)
No description available.
224

Genetic Counseling Referrals and Somatic Landscapes in Adolescent and Young Adults (AYAs) with Acute Myeloid Leukemia (AML)

Keel, Emma M. 22 July 2022 (has links)
No description available.
225

Interpreting the Genetic Revolution: A History of Genetic Counseling in the United States, 1930-2000.

Stillwell, Devon 20 August 2014 (has links)
<p>This dissertation explores the social history of genetic counseling in the United States between 1930 and 2000. I situate genetic counselors at the interstices of medicine, science, and an increasingly “geneticized” society. My study emphasizes two central themes. First, genetic counselors have played a crucial role in bridging the “old eugenics” and the “new genetics” as mediators of genetic reproductive technologies. Genetic counselors negotiated the rights and responsibilities of genetic citizens in their patient encounters. Discourses of privilege and duty were also extrapolated outward to public debates about the new genetics, demonstrating the highly-politicized contexts in which counselors practice and women make reproductive choices. Second, I interrogate the professionalization process of genetic counseling from a field led by male physician-geneticists in the 1940s and 50s, to a profession dominated by women with Masters degrees by the 1980s and 90s. This transformation is best understood through the framework of a “system of professions,” and counselors’ professional position between “sympathy and science.” These frameworks similarly structured the client-counselor relationship, which also centered on concepts of risk, the promotion of patient autonomy, and the ethics of non-directiveness and client-centeredness. These principles distanced counselors from their field’s eugenic origins and the traditional doctor-patient relationship. I emphasize the voices of genetic counselors based on 25 oral history interviews, and hierarchies of gender, race, and educational status at work in the profession’s history. A study of genetic counseling is an important contribution to the histories of health and medicine, medical sociology, bioethics, disability studies, and gender and women’s studies.</p> / Doctor of Philosophy (PhD)
226

Validation of Copy Number Variants Associated with Schizophrenia Risk in an Irish Population and Implications to Clinical Practice

Elves, Rachel L 13 July 2013 (has links)
Schizophrenia is a complex disorder affecting 1% of the population and is highly heritable, but the majority of contributing genetic factors has remained elusive. Current risk estimates for clinical practice are primarily determined by family history and associated empirical risk. Copy number variants (CNVs) may hold the key to explaining the missing heritability in schizophrenia research; schizophrenia risk estimates as high as 30% have been found for the most-studied CNV associated with schizophrenia, 22q11. Currently, there are methods to identify CNVs though previously collected data from SNP microarrays that would facilitate these types of studies. To determine if algorithms that call CNVs from microarray data are robust four genomic regions with putative CNVs called by the Wellcome Trust Consortium using Birdseye in Birdsuite with Affymetrix 6.0 array raw SNP intensities, primarily affecting genes CHD1L, COX5B, PAK7, ZFYVE20, were validated using Taqman real-time qPCR assays in 29 samples by research groups at VCU and Dublin. CNVs called from the algorithm were 100% validated at VCU though there were false negatives from the algorithm that were validated. Two samples at loci with putative duplications were not called by the Dublin group, which may be because of differing sensitivities of the Taqman assays to be able to detect a 50% difference in copy number between duplications and diploid controls, or because of another technical or analytical difference between the two sites. Deletion frequency of one common CNV found in the gene ERBB4, was assessed by qPCR in both Irish singleton (ICCSS) and Irish family (IHDSF) samples and compared with Irish control (Trinity Biobank) and North American control populations. The ERBB4 deletion frequency was not significantly different when comparing the Irish controls to the Irish singleton or the Irish family samples though the family samples were different when compared against the North American control population, which suggests population stratification, rather than a true association between ERBB4 and increased schizophrenia risk. Current clinical practice has been improved by knowledge and evaluation of CNV-related disorders that include risk for psychosis and additional phenotypes. Genotyping of individuals with known psychosis has led to improved patient care for non-psychosis-related phenotypes associated with CNVs. Individuals with suspected genomic disorders that are found to have CNVs can be counseled on potential psychosis risk and potential risk to their offspring. Recurrent CNVs may hold promise in future clinical practice in order to individualize risk estimates in the general patient population, and increase the number of individuals able to receive anticipatory treatment to minimize disease severity.
227

Estudo de genes e variantes genéticas associadas ao câncer de mama familial: impactos no aconselhamento genético / Study of genes and genetic variants associated with familial breast cancer: impacts on genetic counseling

Carmo, Gabriel Bandeira do 30 November 2018 (has links)
Dentre todos os tipos de câncer, excluindo-se o câncer de pele do tipo não melanoma, o de mama é o mais frequente em mulheres, sendo a segunda maior causa de morte por neoplasias nesse segmento da população. Em determinadas famílias, a incidência de câncer é superior à esperada para a população em geral, devido principalmente ao compartilhamento de fatores ambientais e/ou mutações genéticas responsáveis por facilitar ou dirigir a oncogênese. Os indivíduos que apresentam câncer de mama e histórico familial dessa patologia são descritos dentro do grupo câncer de mama familial (CMF), responsável por aproximadamente 5 a 10% do total de casos de câncer de mama. Atualmente, pacientes com CMF são frequentemente testados para mutações nos genes BRCA1 e BRCA2. Entretanto, estima-se que as variantes patogênicas presentes nos dois genes são responsáveis por somente 20% dos casos de CMF em que a etiologia genética é conhecida. Com relação aos testes genéticos para predisposição hereditária ao câncer de mama, torna-se relevante, portanto, a reavaliação da constituição dos painéis multigênicos frente ao estado do conhecimento científico atual, contemplando-se as mais recentes atualizações acerca dos genes e variantes genéticas associadas ao CMF. Neste trabalho, realizamos uma revisão bibliográfica que identificou 45 genes com associação estatística ao CMF, dentre eles 16 são frequentemente avaliados em painéis multigênicos brasileiros e internacionais. Em análise in silico, avaliamos as funções celulares e interações entre os produtos gênicos associados à patologia. Nossos resultados sugerem a adição de oito genes à composição de painéis multigênicos realizados no Brasil, EUA e Europa para avaliação da predisposição hereditária ao câncer de mama. Essa análise crítica pode auxiliar o aprimoramento de estratégias de prevenção, triagem, manejo clínico e determinação do risco de ocorrência e recorrência, com impactos sobre o aconselhamento genético (AG) oferecido aos pacientes afetados pelo câncer familial e seus familiares. Complementarmente, avaliamos as variantes gênicas presentes em pacientes com câncer de mama que realizaram o painel multigênico para predisposição hereditária ao câncer no Centro de Pesquisa sobre o Genoma Humano e Células-Tronco (CEGH-CEL). As frequências de mutações da coorte do CEGH-CEL são semelhantes às obtidas em estudos internacionais, possibilitando a utilização de painéis multigênicos com composições similares em populações de diversas localidades / Of all types of cancer, except for non-melanoma skin cancer, breast cancer is the most common among women, and it\'s the second leading cause of death by neoplasia in this segment of the population. In some families, the incidence rates of cancer are higher than expected for the general population because of the environmental factors and/or genetic mutations responsible for facilitating or driving oncogenesis. The individuals who have breast cancer and a family history of this pathology fall into the group of familial breast cancer (FBC), which is responsible for approximately 5-10% of all breast cancer cases. Currently, patients with FBC are frequently tested for mutations in the BRCA1 and BRCA2 genes. It is estimated, however, that the pathogenic variants of these genes account for only 20% of all FBC cases in which the genetic etiology is known. In relationship to the genetic tests for inherited predisposition for breast cancer, therefore it is relevant to reassess the multi-gene panel composition, considering the state of scientific knowledge today, including the most recent research on the genes and its variants associated with FBC. In this paper we did a literature review, which identified 45 genes statistically associated with FBC, out of which 16 are frequently assessed in multi-gene panels in Brazil and abroad. Through in silico analysis we were able to evaluate cell functions and interactions with gene products associated with cancer. Our results suggest the addition of eight genes to the multi-gene panel composition carried out in Brazil, in the USA and in Europe to assess hereditary predisposition to breast cancer. This critical analysis can assist in the development of preventive actions, triage, clinical management and in determining the risk of occurrence and recurrence, which impacts on the genetic counseling (GC) offered to the patients of familial cancer and their relatives. Additionally, we evaluated the genetic variants in patients diagnosed with breast cancer who have undergone multi-gene panel testing for hereditary predisposition to cancer at the Centro de Pesquisa sobre o Genoma Humano e Células-Tronco (CEGH-CEL). These cohort\'s mutation frequencies are similar to the results in international studies, which could enable the use of multi-gene panels with similar compositions in populations from various locations
228

Angioqueratoma como marcador para o diagnóstico de doença de Fabry / Angiokeratoma: a marker for the diagnosis of Fabry disease

Kelmann, Samantha Vernaschi 19 November 2013 (has links)
INTRODUÇÃO: A Doença de Fabry (DF) é uma doença lisossomal de herança ligada ao X, causada pela deficiência da enzima alfa-galactosidase A (alfa-Gal A), que leva ao acúmulo gradual de glicoesfingolipídeos, em especial a globotriaosilceramida, nos lisossomos do endotélio vascular de tecidos cardíaco, renal, cerebral, olhos e pele. Os principais sintomas iniciais são: dores neuropáticas de extremidades, hipoidrose, dores abdominais recorrentes, angioqueratomas e córnea verticillata. As complicações, que aparecem a partir da terceira década de vida, incluem morte prematura por insuficiência renal, cardíaca e alterações cerebrovasculares. Angioqueratomas são uma das manifestações mais precoces da DF. OBJETIVOS: detectar os portadores da DF a partir de casos de angioqueratoma diagnosticados através de exames anatomopatológicos de biópsia cutânea; descrever o quadro clínico dos afetados e portadoras heterozigotas; realizar aconselhamento genético. MÉTODOS: Uma revisão sistemática de biópsias de pele de 2003 a 2012 foi feita em quatro hospitais universitários. Os pacientes foram convocados para anamnese, exame físico e coleta de história familial. A dosagem enzimática de alfa-Gal A por papel filtro e em leucócitos em homens e a análise molecular por PCR e sequenciamento do gene GLA em homens e mulheres foram realizados naqueles com suspeita de DF. RESULTADOS: Foram localizados 125 registros de angioqueratomas, sendo possível convocar 52 pacientes. Destes, 45 (M:21 e F:24) compareceram para serem examinados. O diagnóstico de DF foi confirmado 3/45 (6,6%), todos do sexo masculino, pela baixa atividade enzimática da alfa-Gal A. A idade dos pacientes eram 16, 21 e 32 anos. Foram identificados outros 13 familiares (cinco homens e oito mulheres) destas 3 famílias. Os principais achados clínicos nos oito homens afetados foram: dores de extremidades (62,5%), angioqueratomas (87,5%), alterações renais (87,5%), cardíacas (12,5%) e presença de córnea verticillata(37,5%) Nas oito mulheres os achados clínicos foram: dores de extremidades (75%), angioqueratomas (12,5%), alterações renais (37,5%) cardíacas (12,5%) e presença de córnea verticillata(0%). A frequência desses achados mostrou-se semelhante à descrita na literatura. As mutações patogênicas no gene GLA, herdadas da mãe, foram identificadas nas 3 famílias e já haviam sido descritas anteriormente. CONCLUSÕES: A DF foi identificada em 3/45 pacientes (6,6%) pelos registros histopatológicos. Portanto, o angioqueratoma é um marcador útil para a detecção da doença. A dosagem enzimática de alfa-Gal A e/ou estudo molecular foram fundamentais para a confirmação diagnóstica da DF. Foi possível identificar outros 13 familiares afetados (5 homens, 8 mulheres), o que reforça a importância do aconselhamento genético. Todos os pacientes apresentavam outros achados clínicos da DF além dos angioqueratomas, os quais, no entanto, não haviam sido diagnosticados. O diagnóstico da DF ainda é tardio e há necessidade de reconhecimento dos médicos sobre as manifestações dessa doença para possibilitar um diagnóstico precoce / INTRODUTION: Fabry disease (FD) is an X-linked lysosomal disorder, caused by the deficiency of the enzyme alfa-galactosidase A (alfa-Gal A), which leads to gradual accumulation of glycosphingolipids, especially globotriaosylceramide, in lysosomes of the vascular endothelium of the cardiac tissue, kidney, brain, eyes and skin. The main initial symptoms are: neuropathic pain in the extremities, hypohidrosis, recurrent abdominal pain, angiokeratomas and cornea verticillata. Complications, which appear from the third decade of life on, include premature death from renal, cardiac and cerebrovascular abnormalities. Angiokeratomas are one of the earliest manifestations of FD. OBJECTIVES: to identify relatives with FD from cases of angiokeratoma diagnosed by pathological examinations of skin biopsy; to describe the clinical features of the affected individuals and heterozygotes; to perform genetic counseling. METHODS: A systematic review of skin biopsies from 2003 to 2012 was done in four university hospitals. Patients were submitted to anamnesis, physical examination and family history collection. The enzymatic assay of alfa-Gal A using dried blood spot in filter paper and leukocytes in men and molecular analysis by PCR and sequencing of the GLA gene in men and women were performed in patients with suspected FD. RESULTS: We found 125 biopsy records of angiokeratomas, and were able to contact 52 patients. Of these, 45 (M: 21 and F: 24) were evaluated. The diagnosis of FD was confirmed in 3/45 (6.6%), all male, with low enzymatic activity of alfa-Gal A. The patients\' ages were 16, 21 and 32 years. We identified 13 other family members (five men and eight women) of these three families. The main clinical findings in the eight affected men were pain in the extremities (62,5%), angiokeratomas (87,5%), renal abnormalities (87,5%), cardiac abnormalities (12,5%) and cornea verticillata (37,5%). In the eight female patients the clinical findings were: pain in the extremities (75%), angiokeratomas (12,5%), renal abnormalities (37,5%) cardiac abnormalities (12,5%) and cornea verticillata (0%). The frequency of these findings was similar to that described in the literature. The pathogenic mutations in the GLA gene, maternally inherited, were identified in three families and had been described previously. CONCLUSIONS: FD was identified in 3/45 patients (6.6%) by histopathologic records. Therefore, angiokeratoma is a useful marker for the detection of disease. The enzymatic measurement of alfa-Gal A and / or molecular studies were essential to confirm the diagnosis of FD. It was possible to identify 13 other affected family members (5 men, 8 women), which reinforces the importance of genetic counseling. All patients, in addition to angiokeratomas, had other clinical manifestations of FD; however these had not been diagnosed before. The diagnosis of FD is still late and doctors need to be aware of the manifestations of this disease to enable early diagnosis
229

Identificação e caracterização de mutações germinativas no gene VHL em famílias com a doença de von Hippel-Lindau / Identification and characterization of germline mutations in the VHL gene in families with von Hippel-Lindau disease

Gomy, Israel 02 July 2008 (has links)
A doença de von Hippel-Lindau (VHL) é uma síndrome de câncer familial herdada de forma autossômica dominante que predispõe ao desenvolvimento de diversos tipos de neoplasias benignas e malignas. É causada por mutações germinativas e somáticas no gene VHL e tem uma incidência aproximada de um a cada 36.000 nascimentos. O gene VHL é um supressor tumoral e codifica a proteína VHL, a qual possui, entre outras funções, uma atividade ubiquitina-ligase, responsável pela poliubiquitinização e degradação proteassômica da subunidade alfa do fator induzido por hipóxia (HIF) na presença de oxigênio. As principais características da doença de VHL são: hemangioblastomas de sistema nervoso central (SNC), principalmente do cerebelo e medula espinhal; angiomas de retina e carcinoma renal de células claras. A probabilidade de desenvolver cada um desses tumores ao longo da vida é estimada em maior que 70%, podendo manifestar-se desde a infância até a fase adulta, principalmente entre a 2ª e 3ª décadas de vida. Classifica-se a doença de VHL conforme a ausência (tipo 1) ou presença de feocromocitoma (tipo 2). A doença do tipo 2 é causada, essencialmente, por mutações missense no gene VHL. As mutações podem ser grandes deleções (20%) ou pontuais (80%) do tipo missense, frameshift, nonsense ou em regiões de splicing. O teste genético é considerado padrão para o manejo clínico dos pacientes e dos familiares em risco, pois permite o diagnóstico e o tratamento precoce das neoplasias, melhorando assim a expectativa de vida. Técnicas de biologia molecular, como o seqüenciamento direto do DNA e o Southern blotting quantitativo, permitem a detecção de mutações germinativas em até 100% dos casos. Técnicas mais recentes, como o PCR quantitativo em tempo real e o MLPA, têm sido empregadas para uma detecção mais eficaz de grandes deleções no gene VHL. Os objetivos do presente estudo foram: (1) diagnosticar os pacientes com suspeita da doença de VHL; (2) identificar e caracterizar mutações germinativas pontuais no gene VHL nos pacientes e em seus parentes de 1º grau; (3) fornecer o aconselhamento genético pré e pós-teste. Dos 37 indivíduos com suspeita da doença de VHL, 14 pacientes de sete famílias diferentes preencheram os critérios diagnósticos. Um paciente apresentou hemangioblastoma cerebelar isolado e sete parentes de 1º grau estavam assintomáticos. Foram realizadas as técnicas de PCR, RFLP e seqüenciamento direto do DNA genômico e após clonagem. Foram identificadas quatro mutações pontuais na região codificadora do gene VHL em quatro famílias diferentes, sendo que duas delas haviam sido descritas na literatura [c.226_228delTTC (F76del), c.217C>T (Q73X)]. As outras duas mutações são descritas pela primeira vez neste estudo e afetam o sitio de splicing (IVS1-1 G>A, IVS2-1 G>C). É provável que as demais três famílias sejam portadoras de deleções germinativas no gene VHL. Em resumo, os resultados apresentados neste estudo ampliam o conhecimento da base molecular da doença de VHL e consiste na primeira pesquisa de pós-graduação produzida pelo ambulatório de aconselhamento genético do câncer do HCFMRP-USP. / Von Hippel-Lindau disease (VHL) is an autosomal dominant hereditary cancer syndrome that predisposes to the development of a variety of benign and malignant tumors. VHL is caused by germline and somatic mutations in the VHL gene and it has an incidence of approximately one in 36,000 livebirths. The VHL gene is a tumor suppressor that is translated into the VHL protein, which has many functions, mainly an ubiquitin-ligase activity, responsible for the polyubiquitylation and proteasomal degradation of the alpha subunit of the hipoxia-inducible factor (HIF) in the presence of oxygen. The main clinical features of VHL are: CNS hemangioblastomas, especially of the cerebellum and spinal cord; retinal angiomas and clear-cell renal carcinomas. The lifetime probability of developing one of these tumors is estimated at more than 70%, whichever may present since childhood until adulthood, more often during the 2nd and 3rd decades. VHL is classified into type 1 (without pheochromocytoma) and type 2 (with pheochromocytoma), the latter being mainly caused by missense mutations. VHL germline mutations may be rearrangements and large deletions (~20%) or point mutations (~80%), such as missense, frameshift, nonsense or in the splicing sites. VHL gene testing is considered standard for the clinical manegement of patients and relatives at risk, whereby it provides early diagnosis and treatment of tumors, improving their life expectancies. Molecular biology techniques such as sequencing and quantitative Southern blotting may detect virtually 100% of VHL germline mutations. More recent methods, such as quantitative real-time PCR and MLPA, have been shown to detect VHL gene gross deletions efficiently. The objectives of this study were: (1) to diagnose patients with VHL clinically; (2) to detect germline point mutations in the VHL gene in the patients and their close relatives at risk; (3) to provide pre and post-testing genetic counseling. Fourteen out of 37 patients from seven unrelated families fulfilled the VHL clinical diagnostic criteria, one patient presented a single cerebellar hemangioblastoma and seven at-risk relatives were still asymptomatic. The methods included: PCR, RFLP, genomic DNA direct sequencing and after cloning. Four germline point mutations in the coding region of the VHL gene were identified, two of whom had been described in literature [c.226_228delTTC (p.F76del), c.217C>T (p.Q73X)]. The other two mutations had not been described so far and affect the splicing sites (IVS1-1 G>A, IVS2-1 G>C). The other three families may carry gross germline deletions in the VHL gene. In conclusion, the outcome presented in this study provides with a greater knowledge of molecular basis of VHL disease and relies on the first post-graduation research carried out at the HCFMRP-USP cancer genetic counseling service.
230

Do topo para a base: aconselhamento genético em famílias a partir da sí­ndrome de tremor/ataxia associada ao X frágil (FXTAS) / From top to bottom: genetic counseling in families ascertained through fragile X-associated tremor/ataxia syndrome (FXTAS)

Ribeiro, Mara Dell\'Ospedale 27 February 2018 (has links)
A Síndrome do X frágil (SXF) é a forma mais comum de deficiência intelectual herdada. É causada por uma mutação no gene FMR1; (Fragile X Mental Retardation 1;), que resulta na deficiência da proteína FMRP (Fragile X Mental Retardation Protein;). O gene FMR1;, localizado no braço longo do cromossomo X, em Xq27.3, possui uma repetição de trinucleotídeos (CGG)n em sua região 5\' não traduzida (região reguladora). Na população geral, o tamanho dessa repetição varia entre 5 a 44 trincas de bases. Uma expansão superior a 200 trinucleotídeos leva à hipermetilação e consequente silenciamento da transcrição do gene. Quando isso ocorre, tem-se uma mutação completa, a causa da SXF. Se a repetição expandida tem de 55 a 200 trincas de bases, chamada de pré-mutação, não ocorre hipermetilação e a proteína FMRP é produzida; portanto, a pré-mutação não está associada à SXF, porém está relacionada a outros quadros clínicos, particularmente à síndrome de tremor/ataxia associada ao X frágil (FXTAS; Fragile-X associated Tremor Ataxia Syndrome;) e à insuficiência ovariana primária associada ao X frágil (FXPOI; Fragile-X associated Primary Ovarian Insufficiency;). O objetivo deste trabalho foi investigar duas famílias cujos casos-índice foram encaminhados para o Centro de Pesquisa sobre o Genoma Humano e Células-Tronco para investigar ataxia espinocerebelar e nos quais a avaliação clínica e a história familial sugeriram a possibilidade de FXTAS; em ambos os pacientes, pré-mutação do gene FMR1; foi detectada. Na Família 1, foi feito o diagnóstico de SXF em um neto da propósita e foi identificada a mutação completa em várias filhas e netas, todas com dificuldade de aprendizado. Na Família 2 não foram identificadas mutações completas e em um dos netos do propósito detectou-se mosaicismo de alelo intermediário e pré-mutação. Assim, diante da variada apresentação fenotípica, a possibilidade de condição associada ao gene FMR1; deve ser considerada frente aos fenótipos de deficiência intelectual, dificuldade de aprendizado, falência ovariana prematura e síndrome de tremor-ataxia. O diagnóstico de FXTAS em famílias em que não há registro de SXF não é frequente, provavelmente diante do desconhecimento dessa possibilidade, mas tem importância fundamental para o aconselhamento genético, particularmente quanto à ocorrência de deficiência intelectual / RIBEIRO, M. D. O. From top to bottom: genetic counseling in families ascertained through fragile X-associated tremor/ataxia syndrome (FXTAS) 2017. 64 f. Dissertação (Mestrado em Aconselhamento Genético e Genômica Humana) - Instituto de Biociências, Universidade de São Paulo, São Paulo, 2017. Fragile X syndrome (FXS) is the most common form of inherited intellectual disability. It is caused by a mutation in the Fragile X Mental Retardation 1 (FMR1;) gene located on the long arm of the X chromosome at Xq27.3 that results in FMRP (Fragile X Mental Retardation Protein) deficiency. The FMR1; gene has a trinucleotide repeat (CGG)n at the 5\' untranslated region (regulatory region); in the general population, this repeat varies in size from 5 to 44 CGG triplets. An expanded repeat of more than 200 trinucleotides leads to hypermethylation and consequent silencing of the gene transcription - the full mutation that causes FXS. The repeat containing 55 to 200 triplets characterizes a premutation; there is no hypermethylation, the gene is transcribed, and the FMRP is produced; then premutations are not associated with FXS, but are related to other clinical conditions: Fragile X-associated Tremor/Ataxia Syndrome (FXTAS) and Fragile X-associated Primary Ovarian Insufficiency (FXPOI). The objective of this study was to investigate two families whose index cases were referred to the Centro de Pesquisa sobre o Genoma Humano e Células-Tronco to investigate spinocerebellar ataxia, whose clinical evaluation and family history suggested the possibility of FXTAS. Both probands were found to carry FMR1; premutations. In Family 1, the diagnosis of FXS was established in a grandson of the proband, and the full mutation was also identified in several of her daughters and granddaughters, all presenting with learning difficulties. In Family 2, no full mutations were detected; a proband\'s grandson had size mosaicism for FMR1; ; alleles, carrying an intermediate allele and a premutation. Although uncommon, possibly due to lack of knowledge about the syndrome, the diagnosis of FXTAS in families without FXS is important for genetic counseling, particularly regarding the occurrence of intellectual disability

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