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OBJECTIVE: Identify the predictive variables of genetic pathogenic results and the impact of test results on epilepsy diagnosis and management. METHODS: Analytical observational design evaluated 130 patients with epilepsy that had performed genetic testing over January 2017 to July 2022. RESULTS: There was a gradual increase in the number of exams performed over the years. The frequency of pathogenic results was 34% (n = 44/130), 8 altered genes with 54% (n = 24/44) of the results. The tests were more positive in patients with developmental delay and/or regression (p = .01). None of the other factors analyzed were associated with higher diagnostic yield. The age at onset of epilepsy brought diagnostic yield to the test (p = .041). Patients with negative genetic test had a reduction in the number of electroencephalograms performed before and after the test (respectively, 3.80 ± 6.37 and .84 ± 1.67; p < .001). SIGNIFICANCE: Facing a large proportion of patients with unexplained epilepsy have a genetic cause a genetic test has the potential to reduce the use of unnecessary diagnostic tests, improve patient outcomes by identifying targeted treatments, and provide families with genetic counseling and risk assessment. But an early genetic testing can be crucial to reach these goals. Even in cases where the genetic test is negative, the study suggests that it still has important implications for patient care and management.

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Progressive retinal atrophy (PRA) is a term used in veterinary medicine to describe inherited and progressive retinal diseases characterized by progressive retinal degeneration and loss of vision. In the Golden Retriever (GR) breed, the mutations associated with PRA have an autosomal recessive inheritance pattern. This study aimed to verify the allele frequencies of PRA1, PRA2, and PRA-prcd in the GR breed in Brazil. A total of 121 GR DNA samples (n = 66 females and n = 55 males) were analyzed. All animals assessed in this study were identified as wild-type (121/121 animals; 100%) for PRA1 and PRA2 mutations; therefore, no carrier or homozygous animals were identified in this population. For the PRA-prcd mutation, 118 animals (118/121 animals; 97.52%) were wild-type. Three animals were genotyped as heterozygous for PRA-prcd (3/121 animals; 2.47%), demonstrating that this mutation is still present in some bloodlines and animals in Brazil, even with a rare prevalence. Five animals (5/121 animals, 4.2%) had a previous eye disease, which was diagnosed by a veterinarian as entropion (2 animals), keratoconjunctivitis sicca (1 animal), corneal ulcer (1 animal), and bilateral blindness (1 animal). This dog with bilateral blindness was identified as wild type homozygous for three mutations assessed in this study; therefore, blindness was not associated with the investigated mutations. In addition, the vast majority (98.3%) of Brazilian breeders assessed in this study were unaware of these mutations as a cause of blindness in the Golden Retriever. Therefore, the present study will serve to disseminate knowledge about PRA and its genetic etiologies, as well as to support future studies with other Brazilian GR populations.

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Seafood international trade has increased the labeling requirements in standards and regulations to include product information that enable traders and consumers to make informed choices. The European Union (EU) Regulation No. 1379/2013 imposes the declaration of an official commercial designation and scientific names for all the fishery and aquaculture products to be offered for sale to the final consumers. DNA analyses are used to enforce this regulation and to test authenticity in processed foods. We compared the performance of two mono-locus approaches for species identification (SI) in 61 Mytilus mussels: the high-resolution melting analysis of the polyphenolic adhesive protein gene and the partial sequencing of the histone H1C gene. The H1C sequences were analyzed with five different methods. Both approaches show discrepancies in the identification of putative hybrids (0.0 < κ < 0.687 and 0.0 < MCC < 0.724). Excluding putative hybrids, methods show substantial to perfect agreement (0.772 < κ < 1.0 and 0.783 < MCC < 1.0). This study highlights the need to use standardized molecular tools, as well as to use multi-locus methods for SI of Mytilus mussels in testing laboratories.

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OBJECTIVES: The present study aimed to contribute to the catalog of genetic mutations involved in the carcinogenic processes of uterine sarcomas (USs) and carcinosarcomas (UCSs), which may assist in the accurate diagnosis of, and selection of treatment regimens for, these conditions. METHODS: We performed gene-targeted next-generation sequencing (NGS) of 409 cancer-related genes in 15 US (7 uterine leiomyosarcoma [ULMS], 7 endometrial stromal sarcoma [ESS], 1 adenosarcoma [ADS]), 5 UCS, and 3 uterine leiomyoma (ULM) samples. Quality, frequency, and functional filters were applied to select putative somatic variants. RESULTS: Among the 23 samples evaluated in this study, 42 loss-of-function (LOF) mutations and 111 missense mutations were detected, with a total of 153 mutations. Among them, 66 mutations were observed in the Catalogue of Somatic Mutations in Cancer (COSMIC) database. TP53 (48%), ATM (22%), and PIK3CA (17%) were the most frequently mutated genes. With respect to specific tumor subtypes, ESS showed mutations in the PDE4DIP, IGTA10, and DST genes, UCS exhibited mutations in ERBB4, and ULMS showed exclusive alterations in NOTCH2 and HER2. Mutations in the KMT2A gene were observed exclusively in ULM and ULMS. In silico pathway analyses demonstrated that many genes mutated in ULMS and ESS have functions associated with the cellular response to hypoxia and cellular response to peptide hormone stimulus. In UCS and ADS, genes with most alterations have functions associated with phosphatidylinositol kinase activity and glycerophospholipid metabolic process. CONCLUSION: This preliminary study observed pathogenic mutations in US and UCS samples. Further studies with a larger cohort and functional analyses will foster the development of a precision medicine-based approach for the treatment of US and UCS.

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Introducción. Los gliomas son las neoplasias malignas primarias más frecuentes del sistema nervioso central, asociadas con una mortalidad y morbilidad elevadas. Las mutaciones en los genes IDH1 e IDH2 de la enzima isocitrato deshidrogenasa (IDH) son clave en la tumorogénesis, y son consideradas un factor pronóstico importante en estas neoplasias. En este estudio se buscó determinar la presencia de mutaciones de los genes IDH1 e IDH2 en pacientes con diagnóstico de glioma difuso en diferentes grados, y su correlación con la sobrevida. Metodología. Se realizó un estudio descriptivo, prospectivo y retrospectivo. La población de estudio fueron pacientes entre los 18 y 45 años con diagnóstico de glioma difuso grado II, III y IV, atendidos en el Hospital San Vicente Fundación de Medellín, entre 2012 y 2017, en quienes se realizó un análisis de mutaciones en los genes IDH1 e IDH2 por secuenciación Sanger y tinción de inmunohistoquímica. Resultados. Se incluyeron 14 pacientes con edad promedio de 37 años, 57% de sexo masculino. Glioblastoma fue la neoplasia más frecuente, diagnosticada en el 42,9% de casos. Por inmunohistoquímica, 10 de los 14 (71,4%) pacientes presentaron mutación de la enzima IDH1, en tanto que 1 de los 11 (9%) pacientes en quienes se logró la secuenciación del gen IDH2, mostró mutación. En general, el 78,6% presentó mutaciones de la enzima IDH, con promedio de sobrevida de 48 meses. Conclusión. Estos hallazgos sugieren que los gliomas son un grupo heterogéneo de tumores, con gran variabilidad genética que impacta en su pronóstico y comportamiento

Introduction. Gliomas are the most common primary malignancies of the central nervous system, associated with high mortality and morbidity. Mutations in the isocitrate dehydrogenase (IDH) enzyme IDH1 and IDH2 genes, are key in tumorigenesis, and are considered an important prognostic factor in these neoplasms. This study aimed to determine the presence of IDH1 and IDH2 gene mutations in patients diagnosed with diffuse glioma in different degrees, and their correlation with survival. Methodology. A descriptive, prospective and retrospective study was conducted. The study population consisted of patients between the ages of 18 and 45 with a diagnosis of grade II, III and IV diffuse glioma, treated at the Hospital San Vicente Fundación in Medellín, between 2012 and 2017, in whom an analysis of IDH1 and IDH2 gene mutations was performed by Sanger sequencing and immunohistochemical staining. Results. Fourteen patients with a mean age of 37 years were included, 57% were male. Glioblastoma was the most frequent neoplasm, diagnosed in 42.9% of the cases. By immunohistochemistry, 10 of the 14 (71.4%) patients had a mutation of the IDH1 enzyme, while 1 of the 11 (9%) patients in whom IDH2 gene sequencing was achieved showed a mutation. In general, 78.6% had IDH enzyme mutations, with an average survival of 48 months. Conclusion. These findings suggest that gliomas are a heterogeneous group of tumors, withgreat genetic variability that impacts their prognosis and behavior

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INTRODUCTION: The risk of developing breast and ovarian cancer is higher in families that carry mutations in BRCA1 or BRCA2 genes, and timely mutation detection is critical. OBJECTIVE: To identify the presence of mutations in the Colombian population and evaluate two testing strategies. METHODS: From a total universe of 853 individual blood samples referred for BRCA1 and BRCA2 typing, 256 cases were analyzed by complete direct sequencing of both genes in Myriad Genetics, and the remaining 597 cases were studied by partial sequencing based on founder mutations in a PCR test designed by ourselves ("Profile Colombia"). RESULTS: We found 107 patients carrying deleterious mutations in this group of patients, 69 (64.5%) located in BRCA1, and 38 (35.5%) in BRCA2. Overall, we detected 39 previously unreported mutations in Colombia (22 in BRCA1 and 17 in BRCA2) and only 4 out of the 6 previously reported founder mutations. Sixty four out of 597 patients (10.7%) studied by "Profile Colombia" showed mutations in BRCA1 or BRCA2, and 41/256 patients (16%) showed mutations by complete BRCA1-BRCA2 sequencing. CONCLUSIONS: The spectrum of 44 different mutations in Colombia as detected in our study is broader than the one previously reported for this country. "Profile Colombia" is a useful screening test to establish both founder and new mutations (detection rate of 10.7%) in cases with family history of breast cancer. Complete sequencing shows a detection rate of 16.0%, and should complement the study of the genetic basis of this disease.

INTRODUCCIÓN: El riesgo de desarrollar cáncer de mama y cáncer de ovario puede transmitirse en familias que porten mutaciones en los genes BRCA1 o BRCA2. La detección de estas mutaciones permite tomar decisiones oportunas en el ámbito de la medicina preventiva. OBJETIVO: Estudiar el espectro de mutaciones en la población colombiana y evaluar dos estrategias de detección. METODOS: Se incluyeron en total 853 pacientes con diagnóstico de cáncer de mama y con solicitud de análisis de los genes BRCA1 y BRCA2. Un total de 256 pruebas se analizaron mediante secuencia directa completa de estos genes en Myriad Genetics, y las restantes 597 se estudiaron mediante secuencia parcial basada en mutaciones fundadoras a través de la prueba "Perfil Colombia", implementada por nosotros. RESULTADOS: Se detectaron 107 pacientes portadores de mutaciones en pacientes colombianos, 69 de las cuales estaban localizadas en BRCA1 y 38 en BRCA2. De estas 39 mutaciones son nuevas (22 en BRCA1 y 17 en BRCA2) y solo se hallaron 4 de las 6 mutaciones reportadas previamente como fundadoras en Colombia. En 64/597 pacientes analizados mediante el "Perfil Colombia" se detectaron mutaciones en BRCA1 o BRCA2, así como en 41/256 pacientes que solicitaron la secuenciación completa de los genes BRCA1 y BRCA2. CONCLUSIONES: El espectro de mutaciones fundadoras en Colombia es más amplio que el reportado anteriormente para este país. El "Perfil Colombia" es una prueba que revela a la vez mutaciones fundadoras y mutaciones nuevas, con una tasa de detección del 10.7%. La secuenciación completa presenta una tasa de detección del 16.0% y puede complementar el diagnóstico de la base genética de esta enfermedad.

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OBJECTIVE: Glioblastoma, the most common and lethal brain tumor, is also one of the most defying forms of malignancies in terms of treatment. Integrated genomic analysis has searched deeper into the molecular architecture of GBM, revealing a new sub-classification and promising precision in the care for patients with specific alterations. METHOD: Here, we present the classification of a Brazilian glioblastoma cohort into its main molecular subtypes. Using a high-throughput DNA sequencing procedure, we have classified this cohort into proneural, classical and mesenchymal sub-types. Next, we tested the possible use of the overexpression of the EGFR and CHI3L1 genes, detected through immunohistochemistry, for the identification of the classical and mesenchymal subtypes, respectively. RESULTS: Our results demonstrate that genetic identification of the glioblastoma subtypes is not possible using single targeted mutations alone, particularly in the case of the Mesenchymal subtype. We also show that it is not possible to single out the mesenchymal cases through CHI3L1 expression. CONCLUSION: Our data indicate that the Mesenchymal subtype, the most malignant of the glioblastomas, needs further and more thorough research to be ensure adequate identification.

OBJETIVO: O glioblastoma (GBM), o tumor cerebral mais comum e mais letal, é também um dos tipos de tumores de mais difícil tratamento. Análises genômicas integradas têm contribuído para um melhor entendimento da arquitetura molecular dos GBMs, revelando uma nova subclassificação com a promessa de precisão no tratamento de pacientes com alterações específicas. Neste estudo, nós apresentamos a classificação de uma casuística brasileira de GBMs dentro dos principais subtipos do tumor. MÉTODO: Usando sequenciamento de DNA em larga escala, foi possível classificar os tumores em proneural, clássico e mesenquimal. Em seguida, testamos o possível uso da hiperexpressão de EGFR e CHI3L1 para a identificação dos subtipos clássico e mesenquimal, respectivamente. RESULTADOS: Nossos resultados deixam claro que a identificação genética dos subtipos moleculares de GBM não é possível utilizando-se apenas um único tipo de mutação, em particular nos casos de GBMs mesenquimais. Da mesma forma, não é possível distinguir os casos mesenquimais apenas com a expressão de CHI3L1. CONCLUSÃO: Nossos dados indicam que o subtipo mesenquimal, o mais maligno dos GBMs, necessita de uma análise mais aprofundada para sua identificação.

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Abstract Introduction: The risk of developing breast and ovarian cancer is higher in families that carry mutations in BRCA1 or BRCA2 genes, and timely mutation detection is critical. Objective: To identify the presence of mutations in the Colombian population and evaluate two testing strategies. Methods: From a total universe of 853 individual blood samples referred for BRCA1 and BRCA2 typing, 256 cases were analyzed by complete direct sequencing of both genes in Myriad Genetics, and the remaining 597 cases were studied by partial sequencing based on founder mutations in a PCR test designed by ourselves ("Profile Colombia"). Results: We found 107 patients carrying deleterious mutations in this group of patients, 69 (64.5%) located in BRCA1, and 38 (35.5%) in BRCA2. Overall, we detected 39 previously unreported mutations in Colombia (22 in BRCA1 and 17 in BRCA2) and only 4 out of the 6 previously reported founder mutations. Sixty four out of 597 patients (10.7%) studied by "Profile Colombia" showed mutations in BRCA1 or BRCA2, and 41/256 patients (16%) showed mutations by complete BRCA1-BRCA2 sequencing. Conclusions: The spectrum of 44 different mutations in Colombia as detected in our study is broader than the one previously reported for this country. "Profile Colombia" is a useful screening test to establish both founder and new mutations (detection rate of 10.7%) in cases with family history of breast cancer. Complete sequencing shows a detection rate of 16.0%, and should complement the study of the genetic basis of this disease.

Resumen Introducción: El riesgo de desarrollar cáncer de mama y cáncer de ovario puede transmitirse en familias que porten mutaciones en los genes BRCA1 o BRCA2. La detección de estas mutaciones permite tomar decisiones oportunas en el ámbito de la medicina preventiva. Objetivo: Estudiar el espectro de mutaciones en la población colombiana y evaluar dos estrategias de detección. Metodos: Se incluyeron en total 853 pacientes con diagnóstico de cáncer de mama y con solicitud de análisis de los genes BRCA1 y BRCA2. Un total de 256 pruebas se analizaron mediante secuencia directa completa de estos genes en Myriad Genetics, y las restantes 597 se estudiaron mediante secuencia parcial basada en mutaciones fundadoras a través de la prueba "Perfil Colombia", implementada por nosotros. Resultados: Se detectaron 107 pacientes portadores de mutaciones en pacientes colombianos, 69 de las cuales estaban localizadas en BRCA1 y 38 en BRCA2. De estas 39 mutaciones son nuevas (22 en BRCA1 y 17 en BRCA2) y solo se hallaron 4 de las 6 mutaciones reportadas previamente como fundadoras en Colombia. En 64/597 pacientes analizados mediante el "Perfil Colombia" se detectaron mutaciones en BRCA1 o BRCA2, así como en 41/256 pacientes que solicitaron la secuenciación completa de los genes BRCA1 y BRCA2. Conclusiones: El espectro de mutaciones fundadoras en Colombia es más amplio que el reportado anteriormente para este país. El "Perfil Colombia" es una prueba que revela a la vez mutaciones fundadoras y mutaciones nuevas, con una tasa de detección del 10.7%. La secuenciación completa presenta una tasa de detección del 16.0% y puede complementar el diagnóstico de la base genética de esta enfermedad.

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As the distribution of Candida species and their susceptibility to antifungal agents have changed, a new means of accurately and rapidly identifying these species is necessary for the successful early resolution of infection and the subsequent reduction of morbidity and mortality. The current work aimed to evaluate ribosomal RNA gene sequencing for the identification of medically relevant Candida species in comparison with a standard phenotypic method. Eighteen reference strains (RSs), 69 phenotypically identified isolates and 20 inconclusively identified isolates were examined. Internal transcribed spaces (ITSs) and D1/D2 of the 26S ribosomal RNA gene regions were used as targets for sequencing. Additionally, the sequences of the ITS regions were used to establish evolutionary relationships. The sequencing of the ITS regions was successful for 88% (94/107) of the RS and isolates, whereas 100% of the remaining 12% (13/107) of the samples were successfully analysed by sequencing the D1/D2 region. Similarly, genotypic analysis identified all of the RS and isolates, including the 20 isolates that were not phenotypically identified. Phenotypic analysis, however, misidentified 10% (7/69) of the isolates. Phylogenetic analysis allowed the confirmation of the relationships between evolutionarily close species. Currently, the use of genotypic methods is necessary for the correct identification of Candida species.

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