Preimplantation genetic testing for monogenic/single gene disorders in a family with Molybdenum co-factor deficiency / 中华医学遗传学杂志

OBJECTIVE@#To carry out preimplantation genetic testing for monogenic/single gene disorders (PGT-M) for a Chinese family affected with Molybdenum co-factor deficiency due to pathogenic variant of MOCS2 gene.@*METHODS@#A family with molybdenum co-factor deficiency who attended to the Maternal and Child Health Care Hospital of Guangxi Zhuang Autonomous Region in April 2020 was selected as the research subject. Trophoblast cells were biopsied from blastocysts fertilized by intracytoplasmic sperm injection. Embryos carrying the MOCS2 gene variant and chromosome copy number variation (CNV) of more than 4 Mb were detected by single-cell whole genome amplification, high-throughput sequencing and single nucleotide polymorphism typing. Embryos without or carrying the heterozygous variant and without abnormal chromosome CNV were transplanted. During mid-pregnancy, amniotic fluid sample was collected for prenatal diagnosis to verify the results of PGT-M.@*RESULTS@#Eleven oocytes were obtained, among which three blastocysts were formed through culturing. Results of genetic testing suggested that one embryo was heterozygous for the maternally derived MOCS2 gene variant and without chromosomal CNV. Following embryo transfer, intrauterine singleton pregnancy was attained. Prenatal diagnosis by amniocentesis at 18 weeks of gestation revealed that the MOCS2 gene variant and chromosomal analysis results were both consistent with that of PGT-M, and a healthy male infant was born at 37+5 weeks of gestation.@*CONCLUSION@#PGT-M has helped the couple carrying the MOCS2 gene variant to have a healthy offspring, and may become an important method for couples carrying other pathogenic genetic variants.

Results of combined newborn hearing and deafness gene screening in Yuncheng area of Shanxi Province / 中华医学遗传学杂志

OBJECTIVE@#To analyze the clinical significance of combined newborn hearing and deafness gene screening in Yuncheng area of Shanxi Province.@*METHODS@#Results of audiological examinations, including transient evoked otoacoustic emission and automatic discriminative auditory brainstem evoked potentials, for 6 723 newborns born in Yuncheng area from January 1, 2021 to December 31, 2021, were retrospectively analyzed. Those who failed one of the tests were considered to have failed the examination. A deafness-related gene testing kit was used to detect 15 hot spot variants of common deafness-associated genes in China including GJB2, SLC26A4, GJB3, and mtDNA12S rRNA. Neonates who had passed the audiological examinations and those who had not were compared using a chi-square test.@*RESULTS@#Among the 6 723 neonates, 363 (5.40%) were found to carry variants. These have included 166 cases (2.47%) with GJB2 gene variants, 136 cases (2.03%) with SLC26A4 gene variants, 26 cases (0.39%) with mitochondrial 12S rRNA gene variants, and 33 cases (0.49%) with GJB3 gene variants. Among the 6 723 neonates, 267 had failed initial hearing screening, among which 244 had accepted a re-examination, for which 14 cases (5.73%) had failed again. This has yielded an approximate prevalence of hearing disorder of 0.21% (14/6 723). Among 230 newborns who had passed the re-examination, 10 (4.34%) were found to have carried a variant. By contrast, 4 out of the 14 neonates (28.57%) who had failed the re-examination had carried a variant, and there was a significant difference between the two groups (P < 0.05).@*CONCLUSION@#Genetic screening can provide an effective supplement to newborn hearing screening, and the combined screening can provide a best model for the prevention of hearing loss, which can enable early detection of deafness risks, targeted prevention measures, and genetic counseling to provide accurate prognosis for the newborns.

A prospective study of genetic screening of 2 060 neonates by high-throughput sequencing / 中华医学遗传学杂志

OBJECTIVE@#To assess the value of genetic screening by high-throughput sequencing (HTS) for the early diagnosis of neonatal diseases.@*METHODS@#A total of 2 060 neonates born at Ningbo Women and Children's Hospital from March to September 2021 were selected as the study subjects. All neonates had undergone conventional tandem mass spectrometry metabolite analysis and fluorescent immunoassay analysis. HTS was carried out to detect the definite pathogenic variant sites with high-frequency of 135 disease-related genes. Candidate variants were verified by Sanger sequencing or multiplex ligation-dependent probe amplification (MLPA).@*RESULTS@#Among the 2 060 newborns, 31 were diagnosed with genetic diseases, 557 were found to be carriers, and 1 472 were negative. Among the 31 neonates, 5 had G6PD, 19 had hereditary non-syndromic deafness due to variants of GJB2, GJB3 and MT-RNR1 genes, 2 had PAH gene variants, 1 had GAA gene variants, 1 had SMN1 gene variants, 2 had MTTL1 gene variants, and 1 had GH1 gene variants. Clinically, 1 child had Spinal muscular atrophy (SMA), 1 had Glycogen storage disease II, 2 had congenital deafness, and 5 had G6PD deficiency. One mother was diagnosed with SMA. No patient was detected by conventional tandem mass spectrometry. Conventional fluorescence immunoassay had revealed 5 cases of G6PD deficiency (all positive by genetic screening) and 2 cases of hypothyroidism (identified as carriers). The most common variants identified in this region have involved DUOX2 (3.93%), ATP7B (2.48%), SLC26A4 (2.38%), GJB2 (2.33%), PAH (2.09%) and SLC22A5 genes (2.09%).@*CONCLUSION@#Neonatal genetic screening has a wide range of detection and high detection rate, which can significantly improve the efficacy of newborn screening when combined with conventional screening and facilitate secondary prevention for the affected children, diagnosis of family members and genetic counseling for the carriers.

Progress of research on chromosomal mosaicism embryos / 中华医学遗传学杂志

Chromosomal mosaicism (CM) is a common phenomenon in preimplantation genetic testing (PGT). In embryos with CM, genetic contents of trophoblastic ectodermal (TE) cells may be different from that of the inner cell mass (ICM) which will develop into the fetus. Embryos with low mosaic proportion could give rise to healthy live births after transplantation, but are accompanied with high pregnancy risks such as high abortion rate. In order to provide a more comprehensive understanding for CM embryos, this article has systematically summarized the recent progress of research on the definition, mechanism, classification, PGT techniques, self-correction mechanism, transplantation outcome and treatment principles for CM embryos.

5p13. 2 Chromosomal duplication syndrome: case report and literature review / Síndrome de duplicação cromossômica 5p13. 2: relato de caso e revisão da literatura

Chromosome 5p13 duplication syndrome represents a contiguous gene syndrome involving duplication of several genes on chromosome 5p13. Some clinical phenotypes are related to it, such as: obsessive-compulsive behavior, small palpebral fissures, intellectual disability, global development delay and ocular hypertelorism. The exact mechanism behind these changes has not well known and further studies are needed for this purpose. Since it is a rare and uncommon clinical situation, the case report contributes to the knowledge of the disease and early diagnosis. This condition mainly affects the cognitive neuromuscular system. We describe an 8-year-old Brazilian patient with the duplication of chromosome 5p13.2, karyotype, whose neurodevelopmental evaluation presented cognitive impairment, severe language delay and atypical physical examination, with ocular hypertelorism, right auricular tags, congenital heart defect and long fingers. The patient was diagnosed by comparative genomic hybridization (CGH)-array revealing a 204Kb of DNA duplication. The exact mechanism behind these structural disorders is still unclear and further studies are needed for this purpose. Nevertheless, the diagnostic suspicion of this genetic alteration that, in general, presents late diagnosis, should be considered to enable better clinical support to the patients and family genetic counseling.

A síndrome da duplicação do cromossomo 5p13 representa uma síndrome genética contígua envolvendo a duplicação de vários genes contidos nesta região. Alguns fenótipos clínicos estão relacionados com ela, tais como: comportamento obsessivo compulsivo, fissuras palpebrais pequenas, déficit intelectual, atraso no desenvolvimento global e hipertelorismo ocular. Por ser uma situação clínica rara, o relato do caso contribui para a disseminação do conhecimento acerca da condição, assim como para seu diagnóstico precoce. Descrevemos uma paciente brasileira de oito anos com a duplicação do cromossomo 5p13.2, que na avaliação do neurodesenvolvimento apresentou comprometimento cognitivo, grave atraso da linguagem e dismorfismos como hipertelorismo ocular, apêndice auricular direito, sopro cardíaco, relacionado a defeito do septo ventricular, e dedos alongados. A paciente foi diagnosticada por meio da pesquisa molecular (CGH)-array com ganho de 204Kb de DNA. O mecanismo exato por trás dessas alterações estruturais ainda não está claro e são necessários mais estudos para este fim. Não obstante, a suspeita diagnóstica dessa alteração genética que, em geral, apresenta diagnóstico tardio, deve ser aventada para viabilizar melhor suporte clínico aos pacientes e aconselhamento genético familiar.

Rare inherited kidney diseases: an evolving field in Nephrology / Doenças renais hereditárias raras: um campo em evolução na Nefrologia

Abstract There are more than 150 different rare genetic kidney diseases. They can be classified according to diagnostic findings as (i) disorders of growth and structure, (ii) glomerular diseases, (iii) tubular, and (iv) metabolic diseases. In recent years, there has been a shift of paradigm in this field. Molecular testing has become more accessible, our understanding of the underlying pathophysiologic mechanisms of these diseases has evolved, and new therapeutic strategies have become more available. Therefore, the role of nephrologists has progressively shifted from a mere spectator to an active player, part of a multidisciplinary team in the diagnosis and treatment of these disorders. This article provides an overview of the recent advances in rare hereditary kidney disorders by discussing the genetic aspects, clinical manifestations, diagnostic, and therapeutic approaches of some of these disorders, named familial focal and segmental glomerulosclerosis, tuberous sclerosis complex, Fabry nephropathy, and MYH-9 related disorder.

Resumo As doenças renais genéticas raras compreendem mais de 150 desordens. Elas podem ser classificadas segundo achados diagnósticos como (i) distúrbios do crescimento e estrutura, (ii) doenças glomerulares, (iii) tubulares e (iv) metabólicas. Nos últimos anos, houve uma mudança de paradigma nesse campo. Os testes moleculares tornaram-se mais acessíveis, nossa compreensão sobre os mecanismos fisiopatológicos subjacentes a essas doenças evoluiu e novas estratégias terapêuticas foram propostas. Portanto, o papel do nefrologista mudou progressivamente de mero espectador a participante ativo, parte de uma equipe multidisciplinar, no diagnóstico e tratamento desses distúrbios. O presente artigo oferece um panorama geral dos recentes avanços a respeito dos distúrbios renais hereditários raros, discutindo aspectos genéticos, manifestações clínicas e abordagens diagnósticas e terapêuticas de alguns desses distúrbios, mais especificamente a glomeruloesclerose segmentar e focal familiar, complexo da esclerose tuberosa, nefropatia de Fabry e doença relacionada ao MYH9.

La importancia del consejo genético en el cáncer de mama / The importance of genetic counseling in breast cancer

Resumen El cáncer de mama es uno de los tipos más frecuentes de cáncer en la población femenina y presenta una estrecha relación con la herencia genética. El asesoramiento genético procura informar y guiar a las pacientes durante todo el proceso de identificación y diagnóstico de cáncer de mama hereditario. Por lo que con el presente artículo se pretende demostrar la relevancia del asesoramiento genético en el abordaje de las pacientes con cáncer de mama hereditario. Se realizó una revisión sistemática de la literatura para la selección de publicaciones científicas que aporten conocimiento sobre el cáncer de mama en relación con la herencia genética y otros documentos que demuestren la importancia del asesoramiento genético en pacientes con cáncer de mama hereditario. Con esta revisión, se obtuvo información valiosa sobre la importancia de la implementación del asesoramiento genético, durante la realización de pruebas genéticas, en pacientes con cáncer de mama hereditario.

Abstract Breast cancer is one of the most frequent types of cancer in the female population and has a close relationship with genetic inheritance. Genetic counseling seeks to inform and guide patients throughout the process of identification and diagnosis of hereditary breast cancer. Therefore, this article intends to demonstrate the relevance of genetic counseling in the approach of patients with hereditary breast cancer. It has been made a systematic review of the literature for the selection of scientific publications that provide knowledge about breast cancer in relation to genetic inheritance and other documents demonstrating the importance of genetic counseling in patients with hereditary breast cancer was performed. With this review, valuable information was obtained on the importance of the implementation of genetic counseling, during genetic testing, in patients with hereditary breast cancer.

How diseases became "genetic" / Como as doenças se tornaram "genéticas"

Abstract This article examines the origins of the term "genetic disease." In the late 19 and early 20th century, an earlier idea that diseases that occur in families reflect a vague familiar "predisposition" was replaced by the view that such diseases have specific causes, while Mendelian genetics provided then clues to the patterns of their transmission. The genetictisation of inborn pathologies took a decisive turn with the redefinition, in 1959, of Down syndrome as a chromosomal anomaly, then the development of tests for the diagnosis of other hereditary pathologies. At that time, geneticists distinguished "hereditary" diseases that run in families, from "genetic" conditions that are the result of new mutations during the production of egg and sperm cells. In the latter case, the inborn impairment is produced by an anomaly in the genetic material of the cell, but is not hereditary, because it is not transmitted from one or both parents. In the late 20th and early 21st century, new genomic technologies blurred the distinction between hereditary and genetic impairments, extended the concept of genetic disease, and modified the experience of people living with such a disease.

Resumo O presente artigo tem o objetivo de examinar as origens do termo "doença genética. No final do século XIX e início do XX, a vaga ideia que a doença manifesta entre familiares refletia uma "predisposição" familiar, foi substituída pela visão que essas doenças possuem causas específicas, enquanto a genética mendeliana forneceu as pistas para os padrões de transmissão da doença. A genética das patologias congênitas deu uma guinada decisiva, em 1959, com a redefinição da Síndrome de Down como uma anomalia cromossômica e, depois, com o desenvolvimento de testes para o diagnóstico de outras patologias hereditárias. Naquela época, os geneticistas distinguiam doenças "hereditárias" como aquelas que acometiam os elementos de uma família, de condições "genéticas" que são o resultado de novas mutações ocorridas durante a produção dos óvulos e espermatozoides. Neste último caso, a deficiência inata é causada por uma anomalia do material genético da célula, porque não é transmitida por qualquer um ou ambos os pais. No final do século XX e início do XXI, as novas tecnologias genômicas obscureceram a distinção entre deficiências hereditária e a genética, estenderam o conceito da doença genética e modificaram a experiência das pessoas que vivem com esse tipo de doença.

Pheochromocytoma and paraganglioma: implications of germline mutation investigation for treatment, screening, and surveillance

ABSTRACT Objective Paraganglioma (PGL) and pheochromocytoma (PCC) are rare neuroendocrine tumors that were considered to be predominantly sporadic. However, with the identification of novel susceptibility genes over the last decade, it is currently estimated that up to 40% of cases can occur in the context of a hereditary syndrome. We aimed to characterize PGL/PCC families to exemplify the different scenarios in which hereditary syndromes can be suspected and to emphasize the importance for patients and their families of making an opportune genetic diagnosis. Materials and methods Retrospective analysis of patients diagnosed with PGL/PCC. Germline mutations were studied using next-generation sequencing panels including SDHA, SDHB, SDHC and SDHD. Clinical data were collected from clinical records, and all patients received genetic counseling. Results We describe 4 families with PGL/PCC and germline mutations in SDH complex genes. 2 families have SDHB mutations and 2 SDHD mutations. The clinical presentation of the patients and their families was heterogeneous, with some being atypical according to the literature. Conclusions PGL/PCC are more commonly associated with a germline mutation than any other cancer type, therefore, all individuals with these types of tumors should undergo genetic risk evaluation. NGS multigene panel testing is a cost-effective approach given the overlapping phenotypes. Individuals with germline mutations associated with PGL/PCC should undergo lifelong clinical, biochemical and imaging surveillance and their families should undergo genetic counseling. For all these reasons, it is critical that all medical staff can suspect and diagnose these inherited cancer predisposition syndromes.

Importance of Genetic Testing in Dilated Cardiomyopathy: Applications and Challenges in Clinical Practice / Importância do Teste Genético na Miocardiopatia Dilatada: Aplicações e Desafios na Prática Clínica

Abstract Dilated cardiomyopathy (DCM) is a clinical syndrome characterized by left ventricular dilatation and contractile dysfunction. It is the most common cause of heart failure in young adults. The advent of next-generation sequencing has contributed to the discovery of a large amount of genomic data related to DCM. Mutations involving genes that encode cytoskeletal proteins, the sarcomere, and ion channels account for approximately 40% of cases previously classified as idiopathic DCM. In this scenario, geneticists and cardiovascular genetics specialists have begun to work together, building knowledge and establishing more accurate diagnoses. However, proper interpretation of genetic results is essential and multidisciplinary teams dedicated to the management and analysis of the obtained information should be considered. In this review, we approach genetic factors associated with DCM and their prognostic relevance and discuss how the use of genetic testing, when well recommended, can help cardiologists in the decision-making process.

Resumo A miocardiopatia dilatada (MCD) é uma síndrome caracterizada por dilatação ventricular esquerda e disfunção contrátil, sendo considerada a causa mais comum de insuficiência cardíaca em adultos jovens. O uso do sequenciamento de nova geração tem contribuído com a descoberta de uma grande quantidade de dados genômicos relacionados à MCD, identificando mutações que envolvem genes que codificam proteínas do citoesqueleto, sarcômero e canais iônicos, os quais são responsáveis por aproximadamente 40% dos casos classificados como MCD idiopática. Nesse cenário, geneticistas e especialistas em genética cardiovascular passaram a atuar em conjunto, agregando conhecimento e estabelecendo diagnósticos mais precisos. No entanto, é fundamental interpretar corretamente os resultados genéticos, sendo necessário criar e fomentar equipes multidisciplinares dedicadas à gestão e análise das informações coletadas. Nesta revisão, abordamos os fatores genéticos associados à MCD, aspectos prognósticos, além de discutirmos como o emprego dos testes genéticos, quando bem indicados, pode ser útil na tomada de decisão na prática clínica dos cardiologistas.

Síndrome de Rett: Análisis molecular del gen MECP2 en pacientes chilenas / Rett syndrome: MECP2 gene molecular analysis in Chilean patients

INTRODUCCIÓN: El síndrome de Rett (RTT) es un trastorno neurológico progresivo caracterizado por producir una regresión del desarrollo psicomotor en niñas previamente sanas. La mayoría de los casos son causados por variantes patogénicas en el gen MECP2, que codifica para la proteína methyl CpG- binding protein 2. OBJETIVO: Describir la frecuencia y el tipo de variantes patogénicas en MECP2 en mujeres chilenas con diagnóstico clínico de RTT. PACIENTES Y MÉTODO: Se invitó a participar en este estudio a mujeres chilenas con sospecha clínica de RTT. Se reunió información clínica mediante un cuestionario. Se analizaron variantes patogénicas en MECP2 mediante el método de secuenciación de Sanger y se utilizó Multiple Ligation-dependant Probe Amplification (MLPA) para la detección de duplicaciones y deleciones. RESULTADO: El estudio incluyó 14 pacientes con sospecha de RTT, de las cuales 8 (57%) pacientes tuvieron variantes patogénicas. Las restantes permanecen sin diagnóstico molecular. CONCLUSIÓN: Variantes patogénicas en MECP2 están presentes en pacientes chilenas con RTT. Es probable que haya otros genes o diagnósticos involucrados en las pacientes sin hallazgos en MECP2. A partir de este trabajo, el diagnóstico molecular está disponible en Chile.

INTRODUCTION: Rett syndrome (RTT) is a progressive neurological disorder characterized by regres sion of psychomotor development in previously healthy girls. Most cases are due to pathogenic va riants in the MECP2 gene which encodes for the methyl CpG-binding protein 2. OBJECTIVE: To des cribe the frequency and type of pathogenic variants in the MECP2 gene in Chilean female patients with clinical diagnosis of RTT. PATIENTS AND METHOD: Chilean women with clinical suspicion of RTT were invited to participate in the study. Clinical data were collected through a questionnaire. MECP2 pathogenic variants were analyzed by Sanger sequencing method and Multiplex Ligation-dependent Probe Amplification (MLPA) was used to detect duplications or deletions. RESULTS: The study in cluded 14 patients with suspected RTT, of which eight (57%) patients had pathogenic variants. The other patients remain without molecular diagnosis. CONCLUSIONS: Pathogenic variants in MECP2 are present in Chilean patients with RTT. It is likely that there are other genes or diagnoses involved in patients without MECP2 findings. As of this study, molecular diagnosis is available in Chile.

Identificación genética de recién nacidos en Perú: un estudio piloto / Genetic identification of newborns in Peru: a pilot study

OBJETIVO: Determinar la factibilidad de la identificación genética a un grupo de recién nacidos prove nientes de un hospital público de Lima-Perú. MATERIAL Y MÉTODO: Estudio descriptivo de corte trans versal, realizado por Registro de Identificación y Estado Civil de Perú, en recién nacidos vivos y sus respectivas madres, provenientes del Hospital Carlos Lanfranco La Hoz (Puente Piedra-Lima) du rante el mes de enero del 2015. Las muestras fueron colectadas en tarjetas FTA (Fast Technology for Analysis of nucleic acids) que permitieron un análisis directo por PCR (Polymerase Chain Reaction) y electroforesis capilar de 21 marcadores genéticos de tipo STR (Short Tandem Repeats), incluyendo el marcador amelogenina para la determinación del sexo. RESULTADOS: Se incluyeron un total de 44 madres y 45 recién nacidos (existió un parto gemelar). La probabilidad de maternidad fue mayor al 99.9% en todos los casos. No se encontraron dificultades en la toma de muestra, ni en el transporte del material. El material biológico obtenido fue suficiente para la obtención de ADN para realizar la identificación del recién nacido. CONCLUSIONES: El procedimiento de identificación genética fue factible de realizar en este hospital. Se identificaron etapas del proceso que podrían mejorarse para la posible aplicación de este procedimiento a una mayor escala en el Perú.

OBJECTIVE: To determine the feasibility of genetic identification in a group of newborns from a public hospital in Lima, Peru. MATERIAL AND METHOD: Descriptive cross-sectional study, carried out by the National Registry of Identification and Civil Status of Peru, on live newborns and their mothers, from the Carlos Lanfranco La Hoz Hospital (Puente Piedra, Lima) during January. 2015. The samples were collected in FTA (Fast Technology for Analysis of nucleic acids) cards that allowed a direct analysis by PCR (Polymerase Chain Reaction) and capillary electrophoresis of 21 STR markers (Short Tandem Repeats), including the amelogenin marker for gender determination. RESULTS: 44 mothers and 45 newborns were included (there was a twin birth). The probability of maternity was higher than 99.9% in all cases. There were no difficulties in the sampling or in transporting the material. The obtained biological material was enough to collect DNA to identify the newborn. CONCLUSIONS: The genetic identification procedure was possible to perform in this hospital. Stages of the process that could be improved were identified for the eventual application of this procedure on a larger scale in Peru.

Predictors of Family Enrollment in a Genetic Cascade Screening Program for Familial Hypercholesterolemia / Preditores de Recrutamento Familiar em um Programa de Rastreamento Genético em Cascata para Hipercolesterolemia Familiar

Abstract Background: Genetic cascade screening is the most cost-effective method for the identification of individuals with familial hypercholesterolemia (FH), but the best strategies for the enrollment of at-risk individuals in a FH screening program are not fully known. Objective: The aim of this study is to identify the best predictors of familial enrollment into genetic screening, using features derived from tested probands. Methods: One hundred and eighty-three index-cases (ICs) with a positive genetic result that had relatives screened from 01/2011 to 07/2015 were included. The response variable was the number of relatives for each enrolled IC. All variables in the study were based on ICs' derived clinical and socioeconomical features. The effect size of predictor variables were obtained through a general linear model using a negative binomial regression link function. Significance was considered with a p < 0.05. Results: Mean IC age when enrolling into the program was 50 years old; 78.1% of individuals reported knowledge of relatives with dyslipidemia. Mean baseline LDL-cholesterol level was 316 ± 90 mg/dL. Referral origin through the cascade program website vs. tertiary care, IC LDL-cholesterol and familial history of high LDL-cholesterol levels were independent predictors associated with a higher number of enrolled relatives. Conclusions: Our data suggest that FH cascade screening programs can predict family enrollment based on IC features. This information may be useful for devising better and more effective screening approaches for at-risk individuals.

Resumo Fundamento: O rastreamento genético em cascata é o método mais economicamente viável para a identificação de indivíduos com hipercolesterolemia familiar, mas as melhores estratégias para o recrutamento de indivíduos em risco em um programa de rastreamento deste tipo não são inteiramente conhecidas. Objetivo: Identificar os melhores preditores de recrutamento familiar em rastreamento genético, usando características derivadas de probandos testados. Métodos: Foram inscritos 183 casos índices com resultado genético positivo, que tiveram familiares rastreados de janeiro de 2011 a julho de 2015. A variável de resposta foi o número de familiares para cada caso índice inscrito. Todas as variáveis do estudo foram baseadas em características clínicas e socioeconômicas derivadas dos casos índices. O tamanho do efeito das variáveis preditoras foi obtido de modelo linear geral utilizando função de associação de regressão binomial negativa. A significância foi considerada com p < 0,05. Resultados: A média de idade dos casos índices ao ingressar no programa foi de 50 anos; 78,1% dos indivíduos relataram conhecimento de familiares com dislipidemia. O nível médio de LDL-colesterol inicial foi de 316 ± 90 mg/dL. Origem de referência por meio do site do programa em cascata vs. cuidados terciários, LDL-colesterol do caso índice e história familiar de níveis elevados de LDL-colesterol foram preditores independentes associados a um maior número de familiares inscritos. Conclusões: Programas de rastreamento genético em cascata da hipercolesterolemia familiar podem prever o recrutamento da família com base nas características do caso índice. Esta informação pode ser útil para criar abordagens de rastreamento melhores e mais eficazes para indivíduos em risco.

Genetic Testing and Pregnancy Outcome Analysis of 362 Fetuses with Congenital Heart Disease Identified by Prenatal Ultrasound / Análise de Teste Genético e de Desfecho da Gestação de 362 Fetos com Cardiopatia Congênita Identificados por Ultrassom Pré-Natal

Abstract Background: Congenital heart defects (CHD), as the most common congenital anomaly, have been reported to be associated with chromosomal abnormalities. Currently, patients with CHD are routinely offered karyotyping and chromosomal microarray (CMA) testing, but the genotype-phenotype relationship has not yet been fully established. Objective: To determine the type and frequency of chromosomal abnormalities in fetuses with CHD and to analyze pregnancy outcomes of fetuses with heart abnormalities caused by different genetic factors. Methods: A total of 362 cases of CHD were enrolled from 2009 to 2016. Detailed ultrasound and laboratory examinations, including karyotyping and CMA, were performed. Outcome was obtained from discharge summaries. Results: Of the 362 fetuses, 220 were found with an isolated CHD, and 142 had CHD with extracardiac anomaly. Among these 362 fetuses, 140 were identified with a genetic cause, including 111 cases with aneuploidy, 10 cases with abnormality of chromosomal structure by karyotyping and 19 cases with pathogenic or likely pathogenic copy-number variations (CNVs) by CMA. The detection rate is close to 38.7%. Only one (identified as trisomy 18 syndrome) in 140 positive cases resulted in perinatal death, with the others being induced. The remaining 222 cases had negative results for both genetic testing and of these cases, 56 resulted in induced labor, and 77 had natural childbirth or caesarean births. The pregnancy outcome of the remaining 89 cases was uncertain. Conclusions: Karyotyping and CMA are effective and accurate prenatal genetic techniques for identifying fetal chromosomal abnormalities associated with cardiac defects, and this can assist clinical doctors to perform appropriate genetic counselling with regard to the etiology and outcome of CHD.

Resumo Fundamento: As cardiopatias congênitas (CCs) são as anomalias congênitas mais comuns, e têm sido associadas a anormalidades cromossômicas. Atualmente, a cariotipagem e a análise cromossômica por microarray (CMA) são oferecidas rotineiramente aos pacientes, mas a relação genótipo-fenótipo ainda não foi totalmente estabelecida. Objetivo: Determinar o tipo e a frequência das anomalias cromossômicas em fetos com CC e analisar os desfechos da gestação de fetos com anormalidades cardíacas causadas por diferentes fatores genéticos. Métodos: No total, foram admitidos 362 casos de CC entre 2009 e 2016. Ultrassonografia e exames laboratoriais detalhados foram realizados, incluindo cariotipagem e CMA. O resultado foi obtido a partir das folhas de epicrise. Resultados: Dos 362 fetos, 220 apresentaram doença coronariana isolada e 142 apresentaram doença coronariana com anomalia extracardíaca. Entre esses 362 fetos, foram identificados 140 com causa genética, incluindo 111 casos com aneuploidia, 10 casos com anormalidade da estrutura cromossômica por cariotipagem e 19 casos com variações no número de cópias (CNVs) patogênicas ou provavelmente patogênicas por CMA. A taxa de detecção é de aproximadamente 38,7%. Apenas um (identificado como síndrome da trissomia do cromossomo 18) em 140 casos positivos resultou em morte perinatal, com as demais sendo induzidas. Os 222 casos restantes tiveram resultados negativos para ambos os testes genéticos e, destes, 56 resultaram em trabalho de parto induzido e 77 tiveram partos naturais ou cesarianas. O desfecho da gravidez dos 89 casos restantes foi incerto. Conclusões: A cariotipagem e a CMA são técnicas genéticas pré-natais eficazes e precisas para a identificação de anomalias cromossômicas fetais associadas a defeitos cardíacos, e isso pode ajudar os médicos a realizar aconselhamento genético adequado com relação à etiologia e ao desfecho das cardiopatias congênitas.

Whole exome trio sequencing reveals a novel LAMP2 mutation found in a male patient with Danon Disease: case report / Secuenciación en trío del exoma revela una nueva mutación LAMP2 encontrada en un paciente masculino con enfermedad de Danon: Reporte de caso

Abstract: Introduction: Danon syndrome was first described by Danon MJ in 1981. This rare disease is a triad consisting of dilated cardiomyopathy, myopathy and mental retardation. The etiology of the disease is associated with mutations in the LAMP2 gene on chromosome X. To date, only mutations in the LAMP2 gene have been associated with the disease. Case presentation: We present the case of a male patient who was initially suspected of being affected by Pompe disease and polymyositis without response to the treatments. He required implantation of pacemakers, and posteriorly a cardioverter defibrillator and isolation of pulmonary veins. Therefore, due to the lack of clarity in the diagnosis, endomyocardial biopsy and genetic studies were performed in order to establish the diagnosis. We found a novel mutation in the LAMP2 gene which had not been reported previously. Discussion: Danon disease is a dominant hereditary syndrome linked to the X chromosome. Danon, specifically is caused by an accumulation of glycogen in muscle cells without alterations in the enzymes responsible for its metabolism. It compromises cardiovascular, muscular and neurological systems, liver and spleen. Cardiac tissue exhibits severe fibrosis, which favors the development of supraventricular and ventricular arrhythmias. As for the diagnosis, the gold standard test is genetic analysis. The treatment is focused on the management of the manifestations that the patient presents, since there is no specific treatment. Conclusions: Danon disease requires further studies in order to obtain epidemiological data for this condition. To date, only mutations in the LAMP2 gene have been documented as the main etiology of Danon disease. We found a single nucleotide deletion in LAMP2 resulting in a frameshift mutation which is the probable cause of Danon disease in this patient.(AU)

Resumen: Introducción: El síndrome de Danon fue descrito por primera vez por MJ Danon en 1981. Esta rara enfermedad es una tríada que consiste en miocardiopatía dilatada, miopatía y retraso mental. La etiología de la enfermedad está asociada con mutaciones en el gen LAMP2 en el cromosoma X. Hasta la fecha, sólo las mutaciones en el gen LAMP2 se han asociado con la enfermedad. Presentación del caso: Presentamos el caso de un paciente masculino que inicialmente se sospechó que estaba afectado por la enfermedad de Pompe y polimiositis sin respuesta a los tratamientos. Requirió la implantación de marcapasos y, posteriormente, un desfibrilador cardioversor y el aislamiento de las venas pulmonares. Entonces, debido a la falta de claridad en el diagnóstico, se realizaron biopsias endomiocardíacas y estudios genéticos para establecer el diagnóstico. Encontramos una nueva mutación en el gen LAMP2 que no se había informado anteriormente. Discusión: La enfermedad de Danon es un síndrome hereditario dominante relacionado con el cromosoma X. Danon, específicamente es causado por una acumulación de glucógeno en las células musculares sin alteraciones en las enzimas responsables de su metabolismo. Compromete los sistemas cardiovascular, muscular y neurológico, el hígado y el bazo. El tejido cardiaco exhibe fibrosis severa, que favorece el desarrollo de arritmias supraventriculares y ventriculares. En cuanto al diagnóstico, la prueba estándar de oro es el análisis genético. El tratamiento se centra en el manejo de las manifestaciones que presenta el paciente, ya que no existe un tratamiento específico. Conclusiones: La enfermedad de Danon requiere más estudios para obtener datos epidemiológicos de esta condición. Hasta la fecha, sólo las mutaciones en el gen LAMP2 se han documentado como la principal etiología de la enfermedad de Danon. Encontramos la eliminación de un solo nucleótido en LAMP2 que resulta en una mutación de cambio de estructura que es la causa probable de la enfermedad de Danon en este paciente.(AU)

Ancestry indicative markers in HIV positive patients in the state of Mato Grosso, Brazil / Marcadores indicativos de ancestralidade em pacientes hiv positivos no estado de Mato Grosso, Brasil

OBJECTIVE: Ancestry Indicative Markers are used to define the allelic frequency of genes from different ethnic groups in populations of certain localities of interest, for analysis of population ancestry and estimation of ethnic mixture. This work aimed to evaluate the frequency of occurrence of the ancestry Indicative Markers SB-19.3, APO, AT3 / ID and PV-92 and to determine the existence of polymorphisms for these markers in the state of Mato Grosso. METHOD: The study aimed to estimate allelic and genotype frequencies, adherence to the Hardy-Weinberg equilibrium and genetic differentiation in the sample of 238 controls formed by HIV free individuals residing in twenty-six different municipalities in the state, collected at the Júlio Muller University Hospital and in a sample of 516 HIV-positive patients also residing in the state. RESULTS: The Hardy-Weinberg equilibrium test revealed an imbalance between the observed and expected proportions of Sb19.3 and APO loci in the control population. Applying the genetic differentiation test, control populations and HIV-positive patients differed for the four loci analyzed. CONCLUSION: The population of the state of Mato Grosso, Brazil proved to be very heterogeneous, confirming hypotheses about its history of colonization. Control populations and HIV-positive patients differed for the four loci analyzed.

OBJETIVO: Os Marcadores Indicativos de Ancestralidade (AIMs) são usados ​​para definir a frequência alélica de genes de diferentes grupos étnicos em populações de determinadas localidades de interesse, para análise de ascendência populacional e estimativa de mistura étnica. Este trabalho teve como objetivo avaliar a freqüência de AIMs (SB-19.3, APO, AT3 / ID e PV-92) e verificar a existência de polimorfismos para esses marcadores no estado de Mato Grosso. MÉTODO: O estudo teve como objetivo estimar as freqüências alélicas e genotípicas, a aderência ao equilíbrio de Hardy-Weinberg e a diferenciação genética na amostra de controles formada por indivíduos residentes em vinte e seis municípios do estado, coletados no Hospital Universitário Júlio Muller e em uma amostra de pacientes HIV positivos também residentes no estado. RESULTADOS: O teste de equilíbrio de Hardy-Weinberg revelou um desequilíbrio entre as proporções observadas e esperadas dos loci Sb19.3 e APO na população de controle. Aplicando o teste de diferenciação genética, a população controle e os pacientes HIV positivos diferenciaram-se para os quatro loci analisados. CONCLUSÃO: A população do estado de Mato Grosso mostrou-se heterogênea, confirmando hipóteses sobre sua história de colonização. A população controle e os pacientes HIV positivos diferenciaram-se para os quatro loci analisados.

Diagnóstico genético de la fibrosis quística: una experiencia provincial de 10 años, Mendoza, Argentina / Genetic diagnosis of cystic fibrosis: a 10-year provincial experience, Mendoza, Argentina

OBJETIVOS: El presente trabajo tiene por objetivo presentar el perfil genético de enfermos fibroquísticos de la Provincia de Mendoza. Pacientes y método: Se estudiaron 105 pacientes derivados del Centro de Fibrosis Quística con diagnóstico clínico o test del sudor positivo. TÉCNICA: INNO-LIPA-CFTR 19 e INNOLIPACFTR17; amplificación genómica mediante PCR multiplex con sondas alelo-específicas. RESULTADOS: Se encontraron 18 mutaciones diferentes causantes de fibrosis quística. El 33,3% corresponde a la F508del; N1303K = 8,5%; G542X = 6,2%; W122X = 3,3%. Se detectó la mutación “africana” 3.120 + 1G > A en el 2,8% de los casos. CONCLUSIÓNES: nuestra prevalencia y espectro de mutaciones en fibrosis quística difieren de otras publicadas en el país. El hallazgo de mutaciones reportadas con mayor frecuencia en países africanos sugiere que nuestra población tiene influencias étnicas diferentes. Se discuten las imprecisiones diagnósticas que han generado en pequeños grupos de enfermos los nuevos avances de laboratorio en genética: enfermos “SMAF-Q Y PAF-Q” (explicación en el texto).

OBJECTIVE: To present the genetic background of Cystic Fibrosis Patients from the Province of Mendoza, Argentina. Patients and method: 105 patients were studied during 10 years. referred from a Cystic Fibrosis Center to the genetic laboratory. Cystic Fibrosis phenotype and /or abnormal sweat test were the referral reasons. TECHNIQUE: INNO-LIPA-CFTR19 and INNOLIPA CFTR 17, genome amplification through PCR multiplex with allele specific probes were used. RESULTS: 18 different mutations were detected F508 del frequency was 33.3%; N1303K: 8.5%; G542X: 6.2%; W122X: 3.3%. The “African” mutation 3120 + 1G > A was found in 2.8% of cases. CONCLUSIONS: Our prevalence of Cystic Fibrosis mutations differs markedly from others reported in our Country. African mutation detection suggests a different ethnic origin for our population. We discuss a small group of patients where genetic studies seem to have created diagnostic difficulties (metabolic syndrome and cystic fibrosis associated pathology).

¿Mejora el estudio genético pre-implantacional la probabilidad de embarazo clínico en parejas sometidas a IVF/ICSI?: Revisión sistemática y meta análisis / Does the pre-implantation genetic study improve the probability of clinical pregnancy in couples undergoing IVF / ICSI?

Una de las principales causas de la falla de los ciclos de fecundación in vitro es la aneuploídia embrionaria. OBJETVO: determinar si las pruebas de tamizaje genético pre-implantacional favorece la posibilidad de embarazos MÉTODOS: Se realizó un revisión sistemática y meta-análisis. Buscamos en las bases PUBMED y EMBAS, estudios publicados entre 2006-2016, que compararan el número de embarazos en fecundación in vitro con y sin tamizeje genético preimplantaicon RESULTADOS: De los 115 artículos analizados, 4 cumplieron los criterios de selección. Evaluamos un total de 221 ciclos con tamizje y 592 sin. No encontramos diferencias en la posibilidad de embarazo (RR 0.88; IC95% 0.71-1.10; p=0.28). Al hacer análisis por subgrupo de técnica de tamizaje, encontramos que el uso de hibridación fluosrescente in situ se asoció a una disminución en la posibilidad de embarazo (3 estudios, RR 0.53; IC95% 0.36-0.77; p=0.0009); mientras que el uso de hibidración genómica comparativa se asoció a un aumeto (1 estudio, RR 1.58; IC 95% 1.24-2.00; p<0.001). CONCLUSION: La eficacia de las pruebas de tamizaje genñeticos son dependientes de la técnica, por lo que se deberia favorecer el uso de hibidración genómica comparativa.

Probably, the main cause in IVF failure is the transfer of aneuploid embryos. OBJECT: To determine if the use of preimplantational genetic screening improves the pregnancy rate in IVF cycles, compared to regular IVF. METHODS: We performed a systematic review and meta-analysis, searching in PUBMED and EMBASE databases studies published between 2006-2016, comparing the pregnancy rates in women undergoing IVF with PGS with that of women undergoing IVF only. RESULTS: Of the 115 articles found, 4 met the selection criteria, with a total of 734 women between 33 and 41 years: 221 with PGS and 592 controls. We found no association between the use of PGS and pregnancy (RR 0.88, 95% CI 0.71-1.10, p = 0.28). However, we performed a subgroup analysis by technique of PGS, and found that fluorescent in situ hybridization was associated with a diminished risk of pregnancy (3 studies;(RR 0.53; 95% CI 0.36-0.77; p = 0.0009), whereas comparative genomic hybridization was associated with an increase (1 study, RR 1.58, CI95% 1,24-2.00, p<0.001). CONCLUSION: The effectivity of PGS is determined by the technique for PGS; therefore, only comparative genomic hybridization should be offered.