RÉSUMÉ
Despite significant advances in the management of coronary artery disease (CAD) and reductions in annual mortality rates in recent decades, this disease remains the leading cause of death worldwide. Consequently, there is an ongoing need for efforts to address this situation. Current clinical algorithms to identify at-risk patients are particularly inaccurate in moderate-risk individuals. For this reason, the need for ancillary tests has been suggested, including predictive genetic screening. As genetic studies rapidly expand and genomic data becomes more accessible, numerous genetic risk scores have been proposed to identify and evaluate an individual's susceptibility to developing diseases, including CAD. The field of genetics has indeed made substantial contributions to risk prediction, particularly in cases where children have parents with premature CAD, resulting in an increased risk of up to 75%. The polygenic risk scores (PRSs) have emerged as a potentially valuable tool for understanding and stratifying an individual's genetic risk. The PRS is calculated as a weighted sum of single-nucleotide variants present throughout the human genome, identifiable through genome-wide association studies, and associated with various cardiometabolic diseases. The use of PRSs holds promise, as it enables the development of personalized strategies for preventing or diagnosing specific pathologies early. Furthermore, it can complement existing clinical scores, increasing the accuracy of individual risk prediction. Consequently, the application of PRSs has the potential to impact the costs and adverse outcomes associated with CAD positively. This narrative review provides an overview of the role of PRSs in the context of CAD.
Apesar dos avanços significativos no tratamento da doença arterial coronariana (DAC) e das reduções nas taxas de mortalidade anuais nas últimas décadas, a DAC continua sendo a principal causa de morte no mundo. Consequentemente, há uma necessidade contínua de esforços para abordar essa situação. Os algoritmos clínicos atuais para identificar pacientes em risco são particularmente imprecisos para indivíduos de risco moderado. Por esse motivo, foi sugerido que são necessários testes auxiliares, incluindo triagem genética preditiva. À medida que os estudos genéticos se expandem rapidamente e os dados genômicos se tornam mais acessíveis, diversos escores de risco genético têm sido propostos para identificar e avaliar a suscetibilidade de um indivíduo ao desenvolvimento de doenças, incluindo a DAC. De fato, o campo da genética tem contribuído substancialmente para a previsão de risco, particularmente nos casos em que as crianças têm genitores com DAC prematura, resultando em um risco aumentado de até 75%. Os escores de risco poligênico (PRSs, do inglês polygenic risk scores) surgiram como uma ferramenta potencialmente valiosa para compreender e estratificar o risco genético de um indivíduo. O PRS é calculado como uma soma ponderada de variantes de nucleotídeo único presentes em todo o genoma humano, identificáveis por meio de estudos de associação genômica ampla, e associadas a várias doenças cardiometabólicas. O uso dos PRSs é promissor, pois permite o desenvolvimento de estratégias personalizadas para prevenir ou diagnosticar patologias específicas de forma precoce. Ademais, seu uso é capaz de complementar os escores clínicos existentes, aumentando a precisão da previsão de risco individual. Consequentemente, a aplicação dos PRSs tem o potencial de impactar positivamente os custos e os desfechos adversos associados à DAC. A presente revisão narrativa oferece uma visão ampla do papel dos PRSs no contexto da DAC.
Sujet(s)
Maladie des artères coronaires , Prédisposition génétique à une maladie , Étude d'association pangénomique , Hérédité multifactorielle , Humains , Maladie des artères coronaires/génétique , Appréciation des risques/méthodes , Prédisposition génétique à une maladie/génétique , Hérédité multifactorielle/génétique , Facteurs de risque , Dépistage génétique/méthodes , Polymorphisme de nucléotide simple/génétique , Genetic Risk ScoreRÉSUMÉ
During the last decades, genomic medicine has made it possible to bring the knowledge of molecular genetics to the field of medical consultation. There are several studies that contribute to the diagnosis, the definition of prognoses, as well as the possibility of providing genetic counseling based on accurate scientific data. Advances in genomic sequencing have promoted the reclassification of entities according to an etiological criterion. Such is the case of epileptic encephalopathies, ataxias, dystonias, among many other neurological conditions. Its implementation requires strategies aimed at achieving the best diagnostic yield. This requires a greater understanding of the molecular bases of each of these practices, as well as their scope. They allow reducing the time until a certain diagnosis is made and the possibility, in some cases, of improving the quality of life of those affected with the use of tailored treatments. The objective of this article was to describe current laboratory studies, their scope and emphasize the algorithms for the study of genetic diseases in general, focusing the attention on those specific to neuropediatrics, in order to promote good practices, avoiding confusion, errors, and unnecessary expenditures of money and shortening the so-called "diagnostic odyssey".
Durante las últimas décadas la medicina genómica ha llevado al ámbito de la consulta médica los conocimientos de la genética molecular. Existe un número de estudios que contribuyen en el diagnóstico, la definición de pronósticos y posibilitan un asesoramiento genético basado en datos científicos certeros. En algunas enfermedades, los avances en la secuenciación genómica, ha promovido la reclasificación de entidades según un criterio etiológico, como las encefalopatías epilépticas, las ataxias, las distonías, entre muchas condiciones médicas. Su implementación requiere, por parte de los médicos, de estrategias tendientes a alcanzar el mejor rédito diagnóstico. Es necesario para ello, una mayor comprensión de las bases moleculares de estas prácticas, así como sus alcances. Permiten reducir los tiempos hasta la concreción de un diagnóstico de certeza y la posibilidad, en algunos casos, de mejorar la calidad de vida de los afectados con la utilización de tratamientos a la medida. El objetivo de este artículo fue describir las técnicas de laboratorio actuales, sus alcances y enfatizar los algoritmos de estudio de las enfermedades genéticas, haciendo hincapié en aquellas propias de la neuropediatría, a fin de propiciar las buenas prácticas, evitando confusiones, errores, erogaciones innecesarias de dinero y acortando la llamada "odisea diagnóstica".
Sujet(s)
Dépistage génétique , Maladies du système nerveux , Humains , Conseil génétique , Dépistage génétique/méthodes , Dépistage génétique/normes , Maladies du système nerveux/génétique , Maladies du système nerveux/diagnostic , Guides de bonnes pratiques cliniques comme sujetRÉSUMÉ
Advances in DNA sequencing technologies, especially next-generation sequencing (NGS), which is the basis for whole-exome sequencing (WES) and whole-genome sequencing (WGS), have profoundly transformed immune-mediated rheumatic disease diagnosis. Recently, substantial cost reductions have facilitated access to these diagnostic tools, expanded the capacity of molecular diagnostics and enabled the pursuit of precision medicine in rheumatology. Understanding the fundamental principles of genetics and diversity in genetic variant classification is a crucial milestone in rheumatology. However, despite the growing availability of DNA sequencing platforms, a significant number of autoinflammatory diseases (AIDs), neuromuscular disorders, hereditary collagen diseases, and monogenic bone diseases remain unsolved, and variants of uncertain significance (VUS) pose a formidable challenge to addressing these unmet needs in the coming decades. This article aims to provide an overview of the clinical indications and interpretation of comprehensive genetic testing in the medical field, addressing the related complexities and implications.
Sujet(s)
Dépistage génétique , Rhumatismes , Humains , Dépistage génétique/méthodes , Rhumatismes/génétique , Rhumatismes/diagnostic , Séquençage nucléotidique à haut débit , Rhumatologie , Exome Sequencing , Maladies neuromusculaires/génétique , Maladies neuromusculaires/diagnostic , Maladies auto-inflammatoires héréditaires/génétique , Maladies auto-inflammatoires héréditaires/diagnostic , RhumatologuesRÉSUMÉ
BACKGROUND: In this article, we delineate a loosely selected cohort comprising patients with a history of early-onset breast cancer and/or a familial occurrence of cancer. The aim of this study was to gain insights into the presence of breast cancer-related gene variants in a population from a micro-region in southern Brazil, specifically the Metropolitan Region of Curitiba. This area exhibits a highly genetically mixed population, mirroring the general characteristics of the Brazilian people. METHODS: Comprehensive next-generation sequencing (NGS) multigene panel testing was conducted on 12 patients from the region, utilizing three different library preparation methods. RESULTS: Two pathogenic variants and one candidate pathogenic variant were identified: BRCA2 c.8878C>T, p.Gln2960Ter; CHEK2 c.1100del, p.Thr367Metfs15, and BRCA2 c.3482dup, p.Asp1161Glufs3. CONCLUSION: BRCA2 c.3482dup, a novel candidate pathogenic variant, previously unpublished, is reported. The prevalence of pathogenic variants in this small cohort is similar to that described in the literature. All different library preparation methods were equally proficient in enabling the detection of these variants.
Sujet(s)
Protéine BRCA2 , Tumeurs du sein , Checkpoint kinase 2 , Séquençage nucléotidique à haut débit , Humains , Protéine BRCA2/génétique , Femelle , Tumeurs du sein/génétique , Tumeurs du sein/anatomopathologie , Checkpoint kinase 2/génétique , Brésil , Adulte d'âge moyen , Adulte , Séquençage nucléotidique à haut débit/méthodes , Dépistage génétique/méthodes , Dépistage génétique/normes , Prédisposition génétique à une maladieRÉSUMÉ
In recent years, significant progress has been made in 5q Spinal Muscular Atrophy therapeutics, emphasizing the importance of early diagnosis and intervention for better clinical outcomes. Characterized by spinal cord motor neuron degeneration, 5q-SMA leads to muscle weakness, swallowing difficulties, respiratory insufficiency, and skeletal deformities. Recognizing the pre-symptomatic phases supported by screening and confirmatory genetic tests is crucial for early diagnosis. This work addresses key considerations in implementing 5q-SMA screening within the Brazilian National Newborn Screening Program and explores Brazil's unique challenges and opportunities, including genetic tests, time-to-patient referral to specialized centers, program follow-up, and treatment algorithms. We aim to guide healthcare professionals and policymakers, facilitating global discussions, including Latin American countries, and knowledge-sharing on this critical subject to improve the care for newborns identified with 5q SMA.
Sujet(s)
Amyotrophie spinale , Dépistage néonatal , Humains , Nouveau-né , Dépistage néonatal/méthodes , Amyotrophie spinale/diagnostic , Amyotrophie spinale/génétique , Amyotrophie spinale/thérapie , Brésil , Dépistage génétique/méthodes , Diagnostic précoce , Soins aux patients/méthodes , Amyotrophies spinales infantiles/diagnostic , Amyotrophies spinales infantiles/génétique , Amyotrophies spinales infantiles/thérapieRÉSUMÉ
BACKGROUND: Albinism is a heterogeneous condition in which patients present complete absence, reduction, or normal pigmentation in skin, hair and eyes in addition to ocular defects. One of the heterogeneous forms of albinism is observed in Hermansky-Pudlak syndrome (HPS) patients. HPS is characterized by albinism and hemorrhagic diathesis due to the absence of dense bodies in platelets. METHODS: In this report, we describe a case of a pair of Puerto Rican siblings with albinism that were clinically diagnosed with HPS during childhood. Since they did not harbor the founder changes in the HPS1 and HPS3 genes common in Puerto Ricans, as adults they wanted to know the type of albinism they had. We performed exome sequencing, validation by PCR, and cloning of PCR products followed by Sanger sequencing in the family members. RESULTS: We discovered no mutations that could explain an HPS diagnosis. Instead, we found the siblings were compound heterozygotes for 4 variants in the Tyrosinase gene: c.-301C>T, c.140G>A (rs61753180; p.G47D), c.575C>A (rs1042602; p.S192Y), and c.1205G>A (rs1126809; p.R402Q). Our results show that the correct diagnosis for the siblings is OCA1B. CONCLUSION: Our study shows the importance of molecular testing when diagnosing a rare genetic disorder, especially in populations were the disease prevalence is higher.
Sujet(s)
Albinisme oculocutané , Syndrome d'Hermanski-Pudlak , Monophenol monooxygenase , Humains , Syndrome d'Hermanski-Pudlak/génétique , Syndrome d'Hermanski-Pudlak/diagnostic , Syndrome d'Hermanski-Pudlak/anatomopathologie , Albinisme oculocutané/génétique , Albinisme oculocutané/diagnostic , Monophenol monooxygenase/génétique , Mâle , Femelle , Adulte , Pedigree , Dépistage génétique/méthodes , Mutation , HétérozygoteRÉSUMÉ
Dear Editor, In relation to the letter expressing concerns about some important points of the article entitled "The usefulness of the genetic panel in the classification and refinement of diagnostic accuracy of Mexican patients with Marfan syndrome and other connective tissue disorders", we would like to comment on the following. Read more in the PDF.
Sujet(s)
Maladies du tissu conjonctif , Syndrome de Marfan , Humains , Syndrome de Marfan/génétique , Syndrome de Marfan/diagnostic , Mexique , Maladies du tissu conjonctif/génétique , Maladies du tissu conjonctif/diagnostic , Dépistage génétique/méthodesRÉSUMÉ
Despite the high prevalence of TP53 pathogenic variants (PV) carriers in the South and Southeast regions of Brazil, germline genetic testing for hereditary breast cancer (HBC) is not available in the Brazilian public health system, and the prevalence of Li-Fraumeni syndrome (LFS) is not well established in other regions of Brazil. We assessed the occurrence of TP53 p.R337H carriers among women treated for breast cancer (BC) between January 2021 and January 2022 at public hospitals of Brasilia, DF, Brazil. A total of 180 patients who met at least one of the NCCN criteria for HBC underwent germline testing; 44.4% performed out-of-pocket germline multigene panel testing, and 55.6% were tested for the p.R337H variant by allelic discrimination PCR. The median age at BC diagnosis was 43.5 years, 93% had invasive ductal carcinoma, 50% had estrogen receptor-positive/HER2 negative tumors, and 41% and 11% were diagnosed respectively at stage III and IV. Two patients (1.11%) harbored the p.R337H variant, and cascade family testing identified 20 additional carriers. The TP53 p.R337H detection rate was lower than that reported in other studies from south/southeast Brazil. Nonetheless, identifying TP53 PV carriers through genetic testing in the Brazilian public health system could guide cancer treatment and prevention.
Sujet(s)
Tumeurs du sein , Prédisposition génétique à une maladie , Mutation germinale , Protéine p53 suppresseur de tumeur , Humains , Femelle , Tumeurs du sein/génétique , Tumeurs du sein/épidémiologie , Brésil/épidémiologie , Adulte , Protéine p53 suppresseur de tumeur/génétique , Adulte d'âge moyen , Dépistage génétique/méthodes , Santé publique , Syndrome de Li-Fraumeni/génétique , Syndrome de Li-Fraumeni/épidémiologie , Sujet âgéRÉSUMÉ
BACKGROUND: In Colombia and worldwide, breast cancer (BC) is the most frequently diagnosed neoplasia and the leading cause of death from cancer among women. Studies predominantly involve hereditary and familial cases, demonstrating a gap in the literature regarding the identification of germline mutations in unselected patients from Latin-America. Identification of pathogenic/likely pathogenic (P/LP) variants is important for shaping national genetic analysis policies, genetic counseling, and early detection strategies. The present study included 400 women with unselected breast cancer (BC), in whom we analyzed ten genes, using Whole Exome Sequencing (WES), know to confer risk for BC, with the aim of determining the genomic profile of previously unreported P/LP variants in the affected population. Additionally, Multiplex Ligation-dependent Probe Amplification (MLPA) was performed to identify Large Genomic Rearrangements (LGRs) in the BRCA1/2 genes. To ascertain the functional impact of a recurrent intronic variant (ATM c.5496 + 2_5496 + 5delTAAG), a minigene assay was conducted. RESULTS: We ascertained the frequency of P/LP germline variants in BRCA2 (2.5%), ATM (1.25%), BRCA1 (0.75%), PALB2 (0.50%), CHEK2 (0.50%), BARD1 (0.25%), and RAD51D (0.25%) genes in the population of study. P/LP variants account for 6% of the total population analyzed. No LGRs were detected in our study. We identified 1.75% of recurrent variants in BRCA2 and ATM genes. One of them corresponds to the ATM c.5496 + 2_5496 + 5delTAAG. Functional validation of this variant demonstrated a splicing alteration probably modifying the Pincer domain and subsequent protein structure. CONCLUSION: This study described for the first time the genomic profile of ten risk genes in Colombian women with unselected BC. Our findings underscore the significance of population-based research, advocating the consideration of molecular testing in all women with cancer.
Sujet(s)
Protéine BRCA2 , Tumeurs du sein , Prédisposition génétique à une maladie , Mutation germinale , Humains , Femelle , Mutation germinale/génétique , Tumeurs du sein/génétique , Tumeurs du sein/anatomopathologie , Tumeurs du sein/épidémiologie , Colombie/épidémiologie , Adulte d'âge moyen , Adulte , Protéine BRCA2/génétique , Protéine BRCA1/génétique , Exome Sequencing , Sujet âgé , Dépistage génétique/méthodes , Protéines mutées dans l'ataxie-télangiectasie/génétiqueRÉSUMÉ
Low-pass whole genome sequencing (LP-WGS) has been applied as alternative method to detect copy number variants (CNVs) in the clinical setting. Compared with chromosomal microarray analysis (CMA), the sequencing-based approach provides a similar resolution of CNV detection at a lower cost. In this study, we assessed the efficiency and reliability of LP-WGS as a more affordable alternative to CMA. A total of 1363 patients with unexplained neurodevelopmental delay/intellectual disability, autism spectrum disorders, and/or multiple congenital anomalies were enrolled. Those patients were referred from 15 nonprofit organizations and university centers located in different states in Brazil. The analysis of LP-WGS at 1x coverage (>50kb) revealed a positive testing result in 22% of the cases (304/1363), in which 219 and 85 correspond to pathogenic/likely pathogenic (P/LP) CNVs and variants of uncertain significance (VUS), respectively. The 16% (219/1363) diagnostic yield observed in our cohort is comparable to the 15%-20% reported for CMA in the literature. The use of commercial software, as demonstrated in this study, simplifies the implementation of the test in clinical settings. Particularly for countries like Brazil, where the cost of CMA presents a substantial barrier to most of the population, LP-WGS emerges as a cost-effective alternative for investigating copy number changes in cytogenetics.
Sujet(s)
Variations de nombre de copies de segment d'ADN , Séquençage du génome entier , Humains , Variations de nombre de copies de segment d'ADN/génétique , Séquençage du génome entier/économie , Séquençage du génome entier/méthodes , Brésil , Mâle , Femelle , Enfant , Déficience intellectuelle/génétique , Déficience intellectuelle/diagnostic , Analyse coût-bénéfice , Analyse sur microréseau/économie , Analyse sur microréseau/méthodes , Trouble du spectre autistique/génétique , Trouble du spectre autistique/diagnostic , Enfant d'âge préscolaire , Malformations multiples/génétique , Malformations multiples/diagnostic , Pays en voie de développement , Adolescent , Troubles du développement neurologique/génétique , Troubles du développement neurologique/diagnostic , Dépistage génétique/économie , Dépistage génétique/méthodesRÉSUMÉ
Dear Editor, We have read the article "The usefulness of the genetic panel in the classification and refinement of diagnostic accuracy of Mexican patients with Marfan syndrome and other connective tissue disorders", recently published in your esteemed journal. We are a team dedicated to diagnosing, approaching, and managing patients with connective tissue disorders, particularly hypermobile spectrum disorders (HSD) and Ehlers-Danlos syndromes (EDS). We appreciate the research group's effort to address the complexity of connective tissue disorders using a multi-panel genetic approach and their analysis of genotype-phenotype associations in a cohort of Mexican patients. However, we would like to express our concern regarding two specific points that we consider crucial for the comprehensive understanding and management of these disorders. Read more in the PDF.
Sujet(s)
Maladies du tissu conjonctif , Syndrome de Marfan , Humains , Syndrome de Marfan/génétique , Syndrome de Marfan/diagnostic , Mexique , Maladies du tissu conjonctif/génétique , Maladies du tissu conjonctif/diagnostic , Dépistage génétique/méthodes , Études d'associations génétiques/méthodesRÉSUMÉ
PURPOSE: To define the spectrum of germline pathogenic variants (PVs) and copy number variant (CNV) in cancer susceptibility genes to the burden of breast and ovarian cancer (BC, OvC) in high-risk Brazilians in Minas Gerais with health insurance, southeast Brazil, undergoing multigene panel testing (MGPT). METHODS: Genotyping eligible individuals with health insurance in the Brazilian healthcare system for Hereditary Breast and Ovarian Cancer Syndrome to undergo molecular testing for 44 or 141-gene panels, a decision that was insurance driven. RESULTS: Overall, 701 individuals clinically defined as high BC/OvC risk, underwent MGPT from 1/2021 to 10/2022, with ~ 50% genotyped with a 44-gene panel and the rest with a 141-gene panel. Overall, 16.4% and 22.6% of genotyped individuals harbored PVs using 44-gene and the 141 gene panel, respectively. The most frequently mutated genes were: BRCA2 (3.7%); BRCA1 (3.6%) and monoallelic MUTYH (3.1%). CONCLUSION: The rate of PVs detected in high-risk individuals in this study was twice the 10% threshold used in Brazilian health guidelines. MGPT doubled the detection rate of PVs in cancer susceptibility genes in high-risk individuals compared with BRCA1/BRCA2 genotyping alone. The spectrum of PVs in Southern Brazil is diverse, with few recurring variants such as TP53 (0.6%), suggesting regional founder effects. The use of MGPT in hereditary cancer in Minas Gerais significantly increased the detection rate of P/LPVs compared to existing guidelines and should be considered as the primary genotyping modality in assessing hereditary cancer risk in Brazil.
Sujet(s)
Prédisposition génétique à une maladie , Dépistage génétique , Mutation germinale , Humains , Femelle , Brésil/épidémiologie , Adulte d'âge moyen , Adulte , Dépistage génétique/méthodes , Syndrome héréditaire de cancer du sein et de l'ovaire/génétique , Syndrome héréditaire de cancer du sein et de l'ovaire/épidémiologie , Variations de nombre de copies de segment d'ADN , Tumeurs de l'ovaire/génétique , Tumeurs de l'ovaire/épidémiologie , Tumeurs de l'ovaire/anatomopathologie , Sujet âgé , Protéine BRCA2/génétique , Tumeurs du sein/génétique , Tumeurs du sein/épidémiologie , Tumeurs du sein/anatomopathologie , Génotype , Protéine BRCA1/génétique , DNA GlycosylasesRÉSUMÉ
PMS2, a Lynch Syndrome gene, presents challenges in genetic testing due to the existence of multiple pseudogenes. This study aims to describe a series of cases harboring a variant in the PMS2CL pseudogene that has been incorrectly assigned to PMS2 with different nomenclatures. We reviewed data from 647 Brazilian patients who underwent multigene genetic testing at a single center to identify those harboring the PMS2 V1:c.2186_2187delTC or V2:c.2182_2184delACTinsG variants, allegedly located at PMS2 exon 13. Gene-specific PCR and transcript sequencing was performed. Among the 647 individuals, 1.8% (12) carried the investigated variants, with variant allele frequencies ranging from 15 to 34%. By visually inspecting the alignments, we confirmed that both V1 and V2 represented the same variant and through gene-specific PCR and PMS2 transcript analysis, we demonstrated that V1/V2 is actually located in the PMS2CL pseudogene. Genomic databases (ExAC and gnomAD) report an incidence of 2.5 - 5.3% of this variant in the African population. Currently, V1 is classified as "uncertain significance" and V2 as "conflicting" in ClinVar, with several laboratories classifying them as "pathogenic". We identified a frequent African PMS2CL variant in the Brazilian population that is misclassified as a PMS2 variant. It is likely that V1/V2 have been erroneously assigned to PMS2 in several manuscripts and by clinical laboratories, underscoring a disparity-induced matter. Considering the limitations of short-read NGS differentiating between certain regions of PMS2 and PMS2CL, using complementary methodologies is imperative to provide an accurate diagnosis.
Sujet(s)
Mismatch repair endonuclease PMS2 , Pseudogènes , Humains , Mismatch repair endonuclease PMS2/génétique , Brésil , Pseudogènes/génétique , Femelle , Mâle , Tumeurs colorectales héréditaires sans polypose/génétique , Adulte d'âge moyen , Dépistage génétique/méthodes , Adulte , Fréquence d'allèle , Sujet âgéRÉSUMÉ
Exome and genome sequencing (ES/GS) are routinely used for the diagnosis of genetic diseases in developed countries. However, their implementation is limited in countries from Latin America. We aimed to describe the results of GS in patients with suspected rare genetic diseases in Colombia. We studied 501 patients from 22 healthcare sites from January to December 2022. GS was performed in the index cases using dried blood spots on filtercards. Ancestry analysis was performed under iAdmix. Multiomic testing was performed when needed (biomarker, enzymatic activity, RNA-seq). All tests were performed at an accredited genetic laboratory. Ethnicity prediction data confirmed that 401 patients (80%) were mainly of Amerindian origin. A genetic diagnosis was established for 142 patients with a 28.3% diagnostic yield. The highest diagnostic yield was achieved for pathologies with a metabolic component and syndromic disorders (p < 0.001). Young children had a median of 1 year of diagnostic odyssey, while the median time for adults was significantly longer (15 years). Patients with genetic syndromes have spent more than 75% of their life without a diagnosis, while for patients with neurologic and neuromuscular diseases, the time of the diagnostic odyssey tended to decrease with age. Previous testing, specifically karyotyping or chromosomal microarray were significantly associated with a longer time to reach a definitive diagnosis (p < 0.01). Furthermore, one out of five patients that had an ES before could be diagnosed by GS. The Colombian genome project is the first Latin American study reporting the experience of systematic use of diagnostic GS in rare diseases.
Sujet(s)
Maladies rares , Séquençage du génome entier , Humains , Colombie , Maladies rares/génétique , Maladies rares/diagnostic , Adulte , Mâle , Femelle , Enfant , Séquençage du génome entier/normes , Adolescent , Enfant d'âge préscolaire , Dépistage génétique/méthodes , Dépistage génétique/normes , Adulte d'âge moyen , NourrissonRÉSUMÉ
BACKGROUND: Neuronal ceroid lipofuscinoses (NCL) are a group of autosomal recessive, inherited, lysosomal, and neurodegenerative diseases that causes progressive dementia, seizures, movement disorders, language delay/regression, progressive visual failure, and early death. Neuronal ceroid lipofuscinosis type 2 (CLN2), caused by biallelic pathogenic variants of the TPP1 gene, is the only NCL with an approved targeted therapy. The laboratory diagnosis of CLN2 is established through highly specific tests, leading to diagnostic delays and eventually hampering the provision of specific treatment for patients with CLN2. Epilepsy is a common and clinically-identifiable feature among NCLs, and seizure onset is the main driver for families to seek medical care. OBJECTIVE: To evaluate the results of the Latin America Epilepsy and Genetics Program, an epilepsy gene panel, as a comprehensive tool for the investigation of CLN2 among other genetic causes of epilepsy. METHODS: A total of 1,284 patients with epilepsy without a specific cause who had at least 1 symptom associated with CLN2 were screened for variants in 160 genes associated with epilepsy or metabolic disorders presenting with epilepsy through an epilepsy gene panel. RESULTS: Variants of the TPP1 gene were identified in 25 individuals (1.9%), 21 of them with 2 variants. The 2 most frequently reported variants were p.Arg208* and p.Asp276Val, and 2 novel variants were detected in the present study: p.Leu308Pro and c.89 + 3G > C Intron 2. CONCLUSION: The results suggest that these genetic panels can be very useful tools to confirm or exclude CLN2 diagnosis and, if confirmed, provide disease-specific treatment for the patients.
ANTECEDENTES: As lipofuscinoses ceroides neuronais (neuronal ceroid lipofuscinoses, NCLs, em inglês) são um grupo de doenças autossômicas recessivas, hereditárias, lisossomais e neurodegenerativas que causam demência progressiva, crises epiléticas, distúrbios de movimento, atraso/regressão da linguagem, deficiência visual progressiva e morte precoce. A lipofuscinose ceroide neuronal tipo 2 (neuronal ceroid lipofuscinosis type 2, CLN2, em inglês), causada por variantes patogênicas bialélicas do gene TPP1, é a única com terapia-alvo aprovada. O diagnóstico laboratorial é realizado por testes específicos, o que leva a atrasos diagnósticos e, consequentemente, prejudica a disponibilização de tratamento. A epilepsia é uma característica comum e clinicamente identificável entre as NCLs, e o início das convulsões é o principal motivo para as famílias buscarem atendimento médico. OBJETIVO: Avaliar os resultados do Programa de Epilepsia e Genética da América Latina, um painel genético, como uma ferramenta abrangente para a investigação de CLN2 entre outras causas genéticas de epilepsia. MéTODOS: Um total de 1.284 pacientes com epilepsia sem uma causa específica e que tinham pelo menos 1 sintoma associado à CLN2 foram rastreados em busca de variantes em 160 genes associados à epilepsia ou a distúrbios metabólicos que apresentam epilepsia, por meio de um painel genético. RESULTADOS: Variantes do gene TPP1 foram identificadas em 25 indivíduos (1,9%), sendo que ; 21 apresentavam duas variantes. As duas variantes mais frequentes foram p.Arg208* e p.Asp276Val, e duas variantes novas foram detectadas neste: p.Leu308Pro e c.89 + 3G > C Intron 2. CONCLUSãO: Os resultados sugerem que os painéis genéticos de epilepsia podem ser uma ferramenta útil para confirmar ou excluir o diagnóstico de CLN2 e, se confirmado, fornecer tratamento específico para os pacientes.
Sujet(s)
Aminopeptidases , Épilepsie , Céroïdes-lipofuscinoses neuronales , Protéases à sérine , Tripeptidyl-peptidase-1 , Humains , Céroïdes-lipofuscinoses neuronales/génétique , Femelle , Mâle , Épilepsie/génétique , Aminopeptidases/génétique , Protéases à sérine/génétique , Enfant , Adolescent , Adulte , Jeune adulte , Enfant d'âge préscolaire , Protéines télomériques/génétique , Dipeptidyl-Peptidases and Tripeptidyl-Peptidases/génétique , Mutation , Dépistage génétique/méthodes , Adulte d'âge moyen , NourrissonRÉSUMÉ
Childhood obesity is a significant public health concern, particularly among Hispanic populations. This study aimed to elucidate the genetic predisposition to obesity in Puerto Rican children of Hispanic descent, addressing a notable gap in existing research. A cohort of 103 children with obesity and hyperphagia underwent genetic screening for rare obesity-related variants. Clinical assessments and family history evaluations were conducted to characterize the demographic and clinical characteristics of the cohort. Genetic testing revealed a high prevalence of variants, with 73% of subjects having at least one reported variant. Pathogenic variants, predominantly associated with obesity-related ciliopathies, were identified in 7% of cases. Additionally, 90% of cases had variants of uncertain significance, highlighting the complexity of genetic contributions to obesity. This study emphasizes the critical need for further investigation into the genetic foundations of obesity, particularly within Hispanic communities. The findings emphasize the importance of early medical evaluation, vigilant monitoring for hyperphagia onset, and targeted interventions tailored to the unique genetic landscape of Puerto Rican children. This research provides a foundational framework for future studies to mitigate the impact of genetic obesity within this population.
Sujet(s)
Prédisposition génétique à une maladie , Hispanique ou Latino , Obésité pédiatrique , Humains , Enfant , Mâle , Femelle , Obésité pédiatrique/génétique , Obésité pédiatrique/épidémiologie , Obésité pédiatrique/ethnologie , Hispanique ou Latino/génétique , Porto Rico/épidémiologie , Génotype , Adolescent , Enfant d'âge préscolaire , Dépistage génétique/méthodes , Hyperphagie/génétiqueRÉSUMÉ
OBJECTIVE: Three gynecologic oncology clinics located in the USA, Brazil, and Mexico collaborated to evaluate their delivery of hereditary cancer genetics services. This descriptive retrospective review study aimed to establish baseline rates and timeliness of guideline-recommended genetics service delivery to patients with ovarian, fallopian tube, primary peritoneal (ovarian), and endometrial cancers at each clinic. METHODS: Patients who were newly diagnosed with ovarian and endometrial cancers between September 1, 2018 and December 31, 2020 were identified from the medical records of the clinics. Genetics service delivery metrics included the rates of mismatch repair deficiency tumor testing for patients with endometrial cancer (microsatellite instability/immunohistochemistry, MSI/IHC), referral to genetics services for patients with ovarian cancer, completed genetics consultations, and germline genetic testing for patients with ovarian and endometrial cancers. Timeliness was calculated as the average number of days between diagnosis and the relevant delivery metric. Descriptive statistics were used to analyze data. RESULTS: In total, 1195 patients (596 with ovarian cancer, 599 with endometrial cancer) were included in the analysis, and rates of genetics service delivery varied by clinic. For patients with ovarian cancer, referral rates ranged by clinic from 32.6% to 89.5%; 30.4-65.1% of patients completed genetics consultation and 32.6-68.7% completed genetic testing. The timeliness to genetic testing for patients with ovarian cancer ranged by clinic from 107 to 595 days. A smaller proportion of patients with endometrial cancer completed MSI/IHC testing (10.0-69.2%), with the average time to MSI/IHC ranging from 15 to 282 days. Rates of genetics consultation among patients with endometrial cancer ranged by clinic from 10.8% to 26.0% and 12.5-16.6% completed genetic testing. CONCLUSIONS: All clinics successfully established baseline rates and timeliness of delivering hereditary cancer genetics services to patients with ovarian and endometrial cancers. Lower rates of delivering genetics services to patients with endometrial cancer warrant additional research and quality improvement efforts.
Sujet(s)
Tumeurs de l'endomètre , Dépistage génétique , Tumeurs de l'ovaire , Humains , Femelle , Tumeurs de l'endomètre/génétique , Tumeurs de l'endomètre/diagnostic , Tumeurs de l'endomètre/thérapie , Tumeurs de l'ovaire/génétique , Tumeurs de l'ovaire/diagnostic , Tumeurs de l'ovaire/thérapie , Études rétrospectives , Mexique/épidémiologie , Brésil/épidémiologie , Adulte d'âge moyen , États-Unis , Dépistage génétique/statistiques et données numériques , Dépistage génétique/méthodes , Adulte , Sujet âgéRÉSUMÉ
A frequent finding after preimplantation genetic diagnostic testing for aneuploidies using next-generation sequencing is an embryo that is putatively mosaic. The prevalence of this outcome remains unclear and varies with technical and external factors. Mosaic embryos can be classified by the percentage of cells affected, type of chromosome involvement (whole or segmental), number of affected chromosomes or affected cell type (inner mass cell, trophectoderm or both). The origin of mosaicism seems to be intrinsic as a post-zygotic mitotic error, but some external factors can play a role. As experience has increased with the transfer of mosaic embryos, clinical practice has gradually become more flexible in recent years. Nevertheless, clinical results show lower implantation, pregnancy and clinical pregnancy rates and higher miscarriage rates with mosaic embryo transfer when compared with the transfer of euploid embryos. Prenatal diagnosis is highly recommended after the transfer of mosaic embryos. This narrative review is intended to serve as reference material for practitioners in reproductive medicine who must manage a mosaic embryo result after preimplantation genetic testing for aneuploidies.
Sujet(s)
Diagnostic préimplantatoire , Grossesse , Femelle , Humains , Diagnostic préimplantatoire/méthodes , Dépistage génétique/méthodes , Implantation embryonnaire , Aneuploïdie , Mosaïcisme , Blastocyste/métabolismeRÉSUMÉ
In this pilot study, we aimed to evaluate the feasibility of whole genome sequencing (WGS) as a first-tier diagnostic test for infants hospitalized in neonatal intensive care units in the Brazilian healthcare system. The cohort presented here results from a joint collaboration between private and public hospitals in Brazil considering the initiative of a clinical laboratory to provide timely diagnosis for critically ill infants. We performed trio (proband and parents) WGS in 21 infants suspected of a genetic disease with an urgent need for diagnosis to guide medical care. Overall, the primary indication for genetic testing was dysmorphic syndromes (n = 14, 67%) followed by inborn errors of metabolism (n = 6, 29%) and skeletal dysplasias (n = 1, 5%). The diagnostic yield in our cohort was 57% (12/21) based on cases that received a definitive or likely definitive diagnostic result from WGS analysis. A total of 16 pathogenic/likely pathogenic variants and 10 variants of unknown significance were detected, and in most cases inherited from an unaffected parent. In addition, the reported variants were of different types, but mainly missense (58%) and associated with autosomal diseases (19/26); only three were associated with X-linked diseases, detected in hemizygosity in the proband an inherited from an unaffected mother. Notably, we identified 10 novel variants, absent from public genomic databases, in our cohort. Considering the entire diagnostic process, the average turnaround time from enrollment to medical report in our study was 53 days. Our findings demonstrate the remarkable utility of WGS as a diagnostic tool, elevating the potential of transformative impact since it outperforms conventional genetic tests. Here, we address the main challenges associated with implementing WGS in the medical care system in Brazil, as well as discuss the potential benefits and limitations of WGS as a diagnostic tool in the neonatal care setting.