RESUMO
OBJECTIVE: To evaluate the prevalence of G6PD deficiency and characterize G202A, A376G and C563T polymorphisms in neonates using molecular assays. METHODS: A total of one thousand samples were tested through quantitative analysis of enzyme activity, detecting 25 G6PD-deficient individuals. Patients identified as deficient were submitted to molecular analysis quantitative real-time polymerase chain reaction - (qPCR) to investigate the presence of variants associated with the deficiency. RESULTS: The total prevalence of G6PD deficient was 2.5%. Of the 25 samples identified as deficient, 21 were submitted to qPCR assay to analyze the presence of G202A, A376G and C563T variants. All samples showed the G202A/A376G genotype, characterizing G6PD A- phenotype. CONCLUSION: The prevalence of G6PD deficiency in the present study was similar to that observed in other study populations in Brazil. Molecular analysis identified in all patients the presence of the genetic polymorphism G202A/A376G, more common in the Brazilian population with G6PD deficiency, which is directly estimated by enzyme activity level.
Assuntos
Deficiência de Glucosefosfato Desidrogenase/epidemiologia , Deficiência de Glucosefosfato Desidrogenase/genética , Polimorfismo Genético , Brasil/epidemiologia , Feminino , Genótipo , Humanos , Recém-Nascido , Masculino , Fenótipo , Polimorfismo Genético/genética , Prevalência , Reação em Cadeia da Polimerase em Tempo Real , Distribuição por SexoRESUMO
ABSTRACT Objective To evaluate the prevalence of G6PD deficiency and characterize G202A, A376G and C563T polymorphisms in neonates using molecular assays. Methods A total of one thousand samples were tested through quantitative analysis of enzyme activity, detecting 25 G6PD-deficient individuals. Patients identified as deficient were submitted to molecular analysis quantitative real-time polymerase chain reaction - (qPCR) to investigate the presence of variants associated with the deficiency. Results The total prevalence of G6PD deficient was 2.5%. Of the 25 samples identified as deficient, 21 were submitted to qPCR assay to analyze the presence of G202A, A376G and C563T variants. All samples showed the G202A/A376G genotype, characterizing G6PD A- phenotype. Conclusion The prevalence of G6PD deficiency in the present study was similar to that observed in other study populations in Brazil. Molecular analysis identified in all patients the presence of the genetic polymorphism G202A/A376G, more common in the Brazilian population with G6PD deficiency, which is directly estimated by enzyme activity level.
RESUMO Objetivo Avaliar a prevalência da deficiência de G6PD e caracterizar, por ensaios moleculares, os polimorfismos G202A, A376G e C563T em recém-nascidos. Métodos Foram testadas mil amostras por meio da análise quantitativa da atividade enzimática, detectando 25 portadores de deficiência de G6PD. Os pacientes identificados como deficientes foram submetidos à análise molecular reação em cadeia da polimerase em tempo real (qPCR) para pesquisa da presença das variantes associadas à deficiência. Resultados A prevalência total de deficientes de G6PD foi de 2,5%. Das 25 amostras identificadas como deficientes, 21 foram submetidas ao qPCR, para análise da presença das variantes G202A, A376G e C563T. Todas as amostras apresentaram o genótipo G202A/A376G, caracterizando fenótipo G6PD A-. Conclusão A prevalência da deficiência da G6PD no presente estudo foi semelhante à verificada em outras populações de estudo no Brasil. A análise molecular identificou em todos os pacientes a presença do polimorfismo genético G202A/A376G, mais comum na população brasileira portadora da deficiência de G6PD, que é diretamente estimada pelo nível de atividade enzimática.
Assuntos
Humanos , Masculino , Feminino , Lactente , Polimorfismo Genético/genética , Deficiência de Glucosefosfato Desidrogenase/genética , Deficiência de Glucosefosfato Desidrogenase/epidemiologia , Fenótipo , Brasil/epidemiologia , Prevalência , Distribuição por Sexo , Reação em Cadeia da Polimerase em Tempo Real , GenótipoRESUMO
The detection of germline mutations in BRCA1 and BRCA2 is essential to the formulation of clinical management strategies, and in Brazil, there is limited access to these services, mainly due to the costs/availability of genetic testing. Aiming at the identification of recurrent mutations that could be included in a low-cost mutation panel, used as a first screening approach, we compiled the testing reports of 649 probands with pathogenic/likely pathogenic variants referred to 28 public and private health care centers distributed across 11 Brazilian States. Overall, 126 and 103 distinct mutations were identified in BRCA1 and BRCA2, respectively. Twenty-six novel variants were reported from both genes, and BRCA2 showed higher mutational heterogeneity. Some recurrent mutations were reported exclusively in certain geographic regions, suggesting a founder effect. Our findings confirm that there is significant molecular heterogeneity in these genes among Brazilian carriers, while also suggesting that this heterogeneity precludes the use of screening protocols that include recurrent mutation testing only. This is the first study to show that profiles of recurrent mutations may be unique to different Brazilian regions. These data should be explored in larger regional cohorts to determine if screening with a panel of recurrent mutations would be effective.
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Proteína BRCA1/genética , Proteína BRCA2/genética , Mutação em Linhagem Germinativa , Adulto , Brasil , Feminino , Humanos , MasculinoRESUMO
OBJECTIVE: To investigate chromosomal abnormalities by CGH-array in patients with dysmorphic features and intellectual disability with normal conventional karyotype. METHODS: Retrospective study, carried out from January 2012 to February 2014, analyzing the CGH-array results of 39 patients. RESULTS: Twenty-six (66.7%) patients had normal results and 13 (33.3%) showed abnormal results - in that, 6 (15.4%) had pathogenic variants, 6 (15.4%) variants designated as uncertain and 1 (2.5%) non-pathogenic variants. CONCLUSION: The characterization of the genetic profile by CGH-array in patients with intellectual disability and dysmorphic features enabled making etiologic diagnosis, followed by genetic counseling for families and specific treatment.
Assuntos
Aberrações Cromossômicas/classificação , Cromossomos Humanos Par 6/genética , Hibridização Genômica Comparativa/métodos , Deficiência Intelectual/genética , Adolescente , Criança , Pré-Escolar , Feminino , Humanos , Cariótipo , Masculino , Estudos Retrospectivos , Adulto JovemRESUMO
ABSTRACT Objective To investigate chromosomal abnormalities by CGH-array in patients with dysmorphic features and intellectual disability with normal conventional karyotype. Methods Retrospective study, carried out from January 2012 to February 2014, analyzing the CGH-array results of 39 patients. Results Twenty-six (66.7%) patients had normal results and 13 (33.3%) showed abnormal results - in that, 6 (15.4%) had pathogenic variants, 6 (15.4%) variants designated as uncertain and 1 (2.5%) non-pathogenic variants. Conclusion The characterization of the genetic profile by CGH-array in patients with intellectual disability and dysmorphic features enabled making etiologic diagnosis, followed by genetic counseling for families and specific treatment.
RESUMO Objetivo Avaliar microalterações cromossômicas por CGH-array em portadores de dismorfias e deficiência intelectual com cariótipo normal. Métodos Estudo retrospectivo, realizado no período de janeiro de 2012 a fevereiro de 2014, analisando os resultados de CGH-array de 39 pacientes. Resultados Apresentaram resultados normais 26 (66,7%) pacientes; 13 (33,3%) tiveram resultados alterados, a saber: 6 (15,4%) com variantes patogênicas, 6 (15,4%) com variantes pertencentes à categoria designada como incerta, e 1 (2,5%) com variantes não patogênicas. Conclusão A caracterização do perfil genético por CGH-array nos pacientes com deficiência intelectual e dismorfias possibilitou complementar o diagnóstico etiológico, permitindo a realização do aconselhamento genético para as famílias e tratamento específico.
