Detection of Mosaic Variants in Mothers of MPS II Patients by Next Generation Sequencing.

Mucopolysaccharidosis type II is an X-linked lysosomal storage disorder caused by mutations in the IDS gene that encodes the iduronate-2-sulfatase enzyme. The IDS gene is located on the long arm of the X-chromosome, comprising 9 exons, spanning approximately 24 kb. The analysis of carriers, in addition to detecting mutations in patients, is essential for genetic counseling, since the risk of recurrence for male children is 50%. Mosaicism is a well-known phenomenon described in many genetic disorders caused by a variety of mechanisms that occur when a mutation arises in the early development of an embryo. Sanger sequencing is limited in detecting somatic mosaicism and sequence change levels of less than 20% may be missed. The Next Generation Sequencing (NGS) has been increasingly used in diagnosis. It is a sensitive and fast method for the detection of somatic mosaicism. Compared to Sanger sequencing, which represents a cumulative signal, NGS technology analyzes the sequence of each DNA read in a sample. NGS might therefore facilitate the detection of mosaicism in mothers of MPS II patients. The aim of this study was to reanalyze, by NGS, all MPS II mothers that showed to be non-carriers by Sanger analysis. Twelve non-carriers were selected for the reanalysis on the Ion PGM and Ion Torrent S5 platform, using a custom panel that includes the IDS gene. Results were visualized in the Integrative Genomics Viewer (IGV). We were able to detected the presence of the variant previously found in the index case in three of the mothers, with frequencies ranging between 13 and 49% of the reads. These results suggest the possibility of mosaicism in the mothers. The use of a more sensitive technology for detecting low-level mosaic mutations is essential for accurate recurrence-risk estimates. In our study, the NGS analysis showed to be an effective methodology to detect the mosaic event.

Genotype-phenotype studies in a large cohort of Brazilian patients with Hunter syndrome.

Mucopolysaccharidosis type II (MPS II) is an X-linked inherited disease caused by pathogenic variants in the IDS gene, leading to deficiency of the lysosomal enzyme iduronate-2-sulfatase and consequent widespread storage of glycosaminoglycans, leading to several clinical consequences, with progressive manifestations which most times includes cognitive decline. MPS II has wide allelic and clinical heterogeneity and a complex genotype-phenotype correlation. We evaluated data from 501 Brazilian patients diagnosed with MPS II from 1982 to 2020. We genotyped 280 of these patients (55.9%), which were assigned to 206 different families. Point mutations were present in 70% of our patients, being missense variants the most frequent. We correlated the IDS pathogenic variants identified with the phenotype (neuronophatic or non-neuronopathic). Except for two half-brothers, there was no discordance in the genotype-phenotype correlation among family members, nor among MPS II patients from different families with the same single base-pair substitution variant. Mothers were carriers in 82.0% of the cases. This comprehensive study of the molecular profile of the MPS II cases in Brazil sheds light on the genotype-phenotype correlation and helps the better understanding of the disease and the prediction of its clinical course, enabling the provision of a more refined genetic counseling to the affected families.

Updated birth prevalence and relative frequency of mucopolysaccharidoses across Brazilian regions.

The mucopolysaccharidoses (MPS) are a group of lysosomal storage disorders caused by 11 enzyme deficiencies, classified into seven types. Data on the birth prevalence of each MPS type are available for only a few countries, and the totality of cases may be underestimated. To determine the epidemiological profile of MPS in each Brazilian region, we analyzed data collected between 1982 and 2019 by a national reference laboratory and identified 1,652 patients. Using data between 1994 and 2018, the birth prevalence (by 100,000 live births) for MPS was 1.57. MPS II was the most common type of MPS in Brazil, and its birth prevalence was 0.48 (0.94 considering only male births). Regarding the number of cases per region, MPS II was the most frequent in the North and Center-West (followed by MPS VI), and also in the Southeast (followed by MPS I); MPS I and MPS II were the most common types in the South; and MPS VI was the most common in the Northeast (followed by MPS II). The differences observed in the relative frequencies of MPS types across Brazilian regions are likely linked to founder effect, endogamy, and consanguinity, but other factors may be present and need further investigation.

Congenital Heart Defects and Dysmorphic Facial Features in Patients Suspicious of 22q11.2 Deletion Syndrome in Southern Brazil.

22q11.2 deletion syndrome (22q11.2DS) is considered one of the most frequently observed chromosomal abnormalities in association with congenital heart disease (CHD), which can also include some combination of other features. Thus, the aim of this work was to verify the profile of dysmorphic features and heart defects found in patients referred to a reference center in Southern Brazil with clinical findings suggestive of 22q11.2DS. In the overall sample group, only patients with dysmorphic facial features (skull, eyes, ear, and nose) associated with CHD (obstructive pulmonary valve ring, truncus arteriosus, and bicuspid aortic valve associated with atrial septal defect and/or right aortic arch) had a 22q11.2 deletion. These findings proved to be reliable clinical criteria for referral to perform fluorescent in situ hybridization investigation for 22q11.2 deletion.

Increased STAT1 Expression in High Grade Serous Ovarian Cancer Is Associated With a Better Outcome.

OBJECTIVE: Recently it has been demonstrated that constitutively activated signal transducer and activator of transcription 1 (STAT1) gene expression may act as a biomarker of ovarian cancer chemotherapy response. In this study, our objective was to validate the use of STAT1 immunohistochemistry as a prognostic biomarker for disease outcome using a cohort derived from Latin America. METHODS: We evaluated a cohort of Brazilian high-grade serous ovarian cancer, comprising 65 patients with outcome data covering more than 5 years to determine the prognostic and predictive value of STAT1 expression levels. High-grade serous ovarian cancer tumors were used to construct a tissue microarray. Exploratory analyses were conducted on clinical, histopathological, and STAT1 expression data that included descriptive statistics and Pearson correlative analyses. Survival curves for disease-free survival and overall survival were obtained by the Kaplan-Meier method, and the significance of homogeneity between the classes was assessed by log-rank statistics (Mantel-Cox). RESULTS: High expression of STAT1 in tumors was significantly associated with improved disease-free survival (P = 0.0256) and overall survival (P = 0.0193). Proportional hazards regression analysis showed STAT1 expression had an independent effect on both disease-free survival (P = 0.0358) and overall survival (P = 0.0469). CONCLUSIONS: These findings from a Brazilian cohort of patients with ovarian cancer reinforce the association of high STAT1 expression with better response to chemotherapy, providing additional validation of this protein as both a prognostic and predictive biomarker. Collectively, these results together with other recently published studies increase the feasibility of using the STAT1 pathway for the development of novel immunomodulator drugs that could enhance response to treatment.

Current state of biomarkers in ovarian cancer prognosis.

High-grade serous ovarian cancer remains one of the most lethal malignancies in women. Despite recent advances in surgical and pharmaceutical therapies, survival rates remain poor. A major impediment in management of this disease, that continues to contribute to poor overall survival rates, is resistance to standard carboplatin-paclitaxel combination chemotherapies. In addition to tumor cell intrinsic mechanisms leading to drug resistance, there is increasing awareness of the crucial role of the tumor microenvironment in mediating natural immune defense mechanisms and selective pressures that appear to facilitate chemotherapy sensitivity. We provide an overview of some of the promising new genetic and immunological biomarkers in ovarian cancer and discuss their biology and their likely clinical utility in future ovarian cancer management.

Prevalência de inaptidão sorológica pelo vírus HCV em doadores de sangue no hemocentro regional de Uberaba (MG), Fundação Hemominas / Prevalence of serological ineligibility due to HCV virus infection among candidates for blood donation at hemocentro regional de Uberaba (Brazil)

Introdução: Hepatite C é causada por flavivírus e sua prevenção é feita especialmente pela triagemsorológica nos bancos de sangue. Objetivos: Calcular a prevalência de doações inaptas pelo vírus da Hepatite C (HCV), analisar o perfil epidemiológico dos inaptos e a tendência de inaptidão por HCV e verificar a concordância entre os testes ELISA e RIBA (Recombinant Immunoblot Assay). Métodos: estudo retrospectivo da sorologia das doações realizadas no Hemocentro Regional de Uberaba (HRU) entre 1995 e 2008, análise do perfil segundo valores proporcionais (para 10.000 doações), estudo de tendência através do coeficiente de correlação linear, com 5por cento de significância e análise da concordância entre ELISA e RIBA com cálculo do coeficiente kappa. Resultados: Foram realizadas, no período, 218.871 doações, sendo 814 (0,4por cento) inaptas por sorologia para o HCV pelo ELISA, com proporções superiores e estatisticamente significativas de inaptos do gênero masculino, idade igual ou superior a 30 anos, procedentes de Uberaba e casados. Houve correlação linear forte inversamente proporcional dos índices de inaptidão para HCV com os anos de estudo (r igual 0,870631). A concordância entre ELISA e RIBA foi de 46,8por cento (kappa igual 0,637). Conclusão: Por meio da análise desses resultados, demonstrou-se uma tendência decrescente de inaptidão para HCV entre doadores, indicando queda do risco de contaminação via transfusão de sangue.

[Decline in the prevalence of HTLV-1/2 among blood donors at the Regional Blood Center of the City of Uberaba, State of Minas Gerais, from 1995 to 2008]. / Declínio da prevalência do HTLV-1/2 em doadores de sangue do Hemocentro Regional da Cidade de Uberaba, Estado de Minas Gerais, 1995 a 2008.

INTRODUCTION: A retrospective study was conducted in order to assess the prevalence and factors associated with seropositivity for HTLV-1/2 between 1995 and 2008 in Uberaba Regional Blood Center, and to describe the seropositive blood donors in relation to gender, age, marital status, skin color and origin. METHODS: Descriptive statistical analysis, chi-square tests and odds ratios were produced to compare proportions, along with scatter charts with linear correlation coefficients. RESULTS: Among the donors tested, the prevalence of seropositivity for HTLV was found to be 0.02%, with indeterminate results in 0.09%. There was a significant reduction in seropositivity for HTLV between 2002 and 2008, compared with the period from 1995 to 2001. Among the seropositive individuals, females were significantly predominant. CONCLUSIONS: The gradual decrease in seropositivity over this period was attributed to the permanent exclusion of seropositive repeat donors and improvement in the clinical screening methods and serological tests over the years, with a positive impact on transfusion safety.

Declínio da prevalência do HTLV-1/2 em doadores de sangue do Hemocentro Regional da Cidade de Uberaba, Estado de Minas Gerais, 1995 a 2008 / Decline in the prevalence of HTLV-1/2 among blood donors at the Regional Blood Center of the City of Uberaba, State of Minas Gerais, from 1995 to 2008

INTRODUCÃO: Estudo retrospectivo com o objetivo de avaliar a prevalência e fatores associados à soropositividade para o HTLV-1/2, no período de 1995 a 2008, no Hemocentro Regional de Uberaba e descrever os doadores soropositivos quanto ao gênero, idade, estado civil, cor de pele e procedência. MÉTODOS: Foram realizados análise estatística descritiva, testes qui-quadrado e odds ratio para comparação de proporções e gráfico de dispersão com coeficiente de correlação linear. RESULTADOS: Dentre x doadores testados, foi encontrada a prevalência de sorologia positiva para o HTLV de 0,02 por cento e indeterminada de 0,09 por cento. Houve uma redução significativa da sorologia positiva para HTLV, no período de 2002 a 2008, em comparação ao período de 1995 a 2001. Dentre os soropositivos, observou predomínio significante no gênero feminino. CONCLUSÕES: Imputamos a queda gradativa de soropositividade no período à exclusão permanente dos doadores de repetição soropositivos e ao aprimoramento dos métodos de triagem clínica e dos testes sorológicos ao longo dos anos com reflexos positivos na segurança transfusional.

INTRODUCTION: A retrospective study was conducted in order to assess the prevalence and factors associated with seropositivity for HTLV-1/2 between 1995 and 2008 in Uberaba Regional Blood Center, and to describe the seropositive blood donors in relation to gender, age, marital status, skin color and origin. METHODS: Descriptive statistical analysis, chi-square tests and odds ratios were produced to compare proportions, along with scatter charts with linear correlation coefficients. RESULTS: Among the donors tested, the prevalence of seropositivity for HTLV was found to be 0.02 percent, with indeterminate results in 0.09 percent. There was a significant reduction in seropositivity for HTLV between 2002 and 2008, compared with the period from 1995 to 2001. Among the seropositive individuals, females were significantly predominant. CONCLUSIONS: The gradual decrease in seropositivity over this period was attributed to the permanent exclusion of seropositive repeat donors and improvement in the clinical screening methods and serological tests over the years, with a positive impact on transfusion safety.