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Introduction Cancer is a multifactorial disease dependent on the influence of genetic and environmental factors. About 10% of cancers are associated with germline mutations, which predispose to a higher risk of developing cancer. Currently, the use of panels that identify susceptibility and/or association genes cancer has been increasingly used, both in clinical practice and in scientific research. Objective To investigate genetic mutations in patients with a profile for hereditary cancer in individuals from a region of northeast Brazil, where there is a high frequency of endogenous and consanguineous marriages. Methods A set of 17 genes ( BRCA1 , BRCA2 , APC , TP53 , PTEN , RET , VHL , RB1 , CDKN2 , CDH1 , CHEK2 , MLH1 , MSH2 , MSH6 , MUTYH , XPA , and XPC ) associated with cancer and hereditary syndromes were analyzed. Fifteen patients with a hereditary cancer profile were evaluated. Results The pathogenic variant found was c.1187G > A (p.Gly396Asp), rs36053993 in the MUTYH gene in a male patient diagnosed with melanoma at the age of 43 years and a family history for this tumor. This gene encodes an important enzyme related to DNA repair and has been associated with other types of cancer, this is the first report of an association with melanoma, the biological plausibility of this association is given once the MUTYH protein is expressed in the skin tissue and is responsible for repairing damage caused, for example, by sun exposure. Conclusion The results of this study suggest that this mutation may be important for the hereditary predisposition to melanoma, but a broader investigation of this mutation is needed.
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PURPOSE: There is a paucity of data on the spectrum and prevalence of pathogenic variants among women of African ancestry in the Northeast region of Brazil. METHODS: We performed BROCA panel sequencing to identify inherited loss-of-function variants in breast cancer susceptibility genes among 292 Brazilian women referred to a single institution cancer risk assessment program. RESULTS: The study included a convenient cohort of 173 women with invasive breast cancer (cases) and 119 women who were cancer-free at the time of ascertainment. The majority of the women self-reported as African-descended (67% for cases and 90.8% for unaffected volunteers). Thirty-seven pathogenic variants were found in 36 (20.8%) patients. While the spectrum of pathogenic variants was heterogeneous, the majority (70.3%) of the pathogenic variants were detected in high-risk genes BRCA1, BRCA2, PALB2, and TP53. Pathogenic variants were also found in the ATM, BARD1, BRIP1, FAM175A, FANCM, NBN, and SLX4 genes in 6.4% of the affected women. Four recurrent pathogenic variants were detected in 11 patients of African ancestry. Only one unaffected woman had a pathogenic variant in the RAD51C gene. Different risk assessment models examined performed well in predicting risk of carrying germline loss-of-function variants in BRCA1 and/or BRCA2 in breast cancer cases. CONCLUSION: The high prevalence and heterogenous spectrum of pathogenic variants identified among self-reported African descendants in Northeast Brazil is consistent with studies in other African ancestry populations with a high burden of aggressive young onset breast cancer. It underscores the need to integrate comprehensive cancer risk assessment and genomic testing in the management of newly diagnosed Black women with breast cancer across the African Diaspora, enabling improved cancer control in admixed underserved and understudied populations.
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Neoplasias de la Mama , Proteína BRCA1/genética , Proteína BRCA2/genética , Brasil/epidemiología , Neoplasias de la Mama/diagnóstico , Neoplasias de la Mama/epidemiología , Neoplasias de la Mama/genética , ADN Helicasas/genética , Femenino , Genes BRCA2 , Predisposición Genética a la Enfermedad , Mutación de Línea Germinal , Humanos , MutaciónRESUMEN
We aimed to assess the current genetics practice to manage patients with Lynch syndrome (LS) across Latin America. A Latin American LS survey was sent out to 52 centres/registries, comprising a total of 12 countries from the region. Overall, 33 centres completed the survey, of which the oldest LS registry was established in 1992 in Sao Paulo (Brazil), and the youngest this year in San Jose (Costa Rica). In total, 87% (26/30) of the participating centres/registries belonging to the nine countries are performing genetic testing. Overall, 1352 suspected families were sequenced. Pathogenic variants were identified in 34% of the families, with slightly differing distribution of variants between females and males. Path_MLH1 variants were identified in 39% of females and 50% of males (p = 0.023), while path_MSH2 were identified in 37% of females and males, followed by path_PMS2 in 11% of females and 8% of males, path_MSH6 in 13% of females and 3% of males (p < 0.001) and path_EPCAM in 0.3% of females and 2% of males. In Latin America, 9 of 12 (75%) participating countries had implemented healthcare for LS. LS screening is inconsistently applied within Latin America healthcare systems because of structural differences in the healthcare systems between the countries.
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Neoplasias Colorrectales Hereditarias sin Poliposis/genética , Predisposición Genética a la Enfermedad/genética , Pruebas Genéticas/métodos , Sistema de Registros/estadística & datos numéricos , Encuestas y Cuestionarios , Adulto , Neoplasias Colorrectales Hereditarias sin Poliposis/diagnóstico , Proteínas de Unión al ADN/genética , Molécula de Adhesión Celular Epitelial/genética , Femenino , Humanos , Masculino , Persona de Mediana Edad , Homólogo 1 de la Proteína MutL/genética , Proteína 2 Homóloga a MutS/genética , América del Sur , Adulto JovenRESUMEN
Colorectal cancer (CRC) is one of the most common cancers in Latin America and the Caribbean, with the highest rates reported for Uruguay, Brazil and Argentina. We provide a global snapshot of the CRC patterns, how screening is performed, and compared/contrasted to the genetic profile of Lynch syndrome (LS) in the region. From the literature, we find that only nine (20%) of the Latin America and the Caribbean countries have developed guidelines for early detection of CRC, and also with a low adherence. We describe a genetic profile of LS, including a total of 2,685 suspected families, where confirmed LS ranged from 8% in Uruguay and Argentina to 60% in Peru. Among confirmed LS, path_MLH1 variants were most commonly identified in Peru (82%), Mexico (80%), Chile (60%), and path_MSH2/EPCAM variants were most frequently identified in Colombia (80%) and Argentina (47%). Path_MSH6 and path_PMS2 variants were less common, but they showed important presence in Brazil (15%) and Chile (10%), respectively. Important differences exist at identifying LS families in Latin American countries, where the spectrum of path_MLH1 and path_MSH2 variants are those most frequently identified. Our findings have an impact on the evaluation of the patients and their relatives at risk for LS, derived from the gene affected. Although the awareness of hereditary cancer and genetic testing has improved in the last decade, it is remains deficient, with 39%-80% of the families not being identified for LS among those who actually met both the clinical criteria for LS and showed MMR deficiency.
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Neoplasias Colorrectales Hereditarias sin Poliposis/diagnóstico , Neoplasias Colorrectales Hereditarias sin Poliposis/epidemiología , Homólogo 1 de la Proteína MutL/genética , Proteína 2 Homóloga a MutS/genética , Neoplasias Colorrectales Hereditarias sin Poliposis/genética , Detección Precoz del Cáncer , Femenino , Adhesión a Directriz , Humanos , América Latina/epidemiología , Masculino , Guías de Práctica Clínica como Asunto , Medición de RiesgoRESUMEN
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 , Mutación de Línea Germinal , Adulto , Brasil , Femenino , Humanos , MasculinoRESUMEN
Identifying the genetic etiology in a person with hearing loss (HL) is challenging due to the extreme genetic heterogeneity in HL and the population-specific variability. In this study, after excluding GJB2 variants, targeted resequencing of 180 deafness-related genes revealed the causative variants in 11 of 19 (58%) Brazilian probands with autosomal recessive HL. Identified pathogenic variants were in MYO15A (10 families) and CLDN14 (one family). Remarkably, the MYO15A p.(Val1400Met) variant was identified in eight families from the city of Monte Santo in the northeast region of Brazil. Haplotype analysis of this variant was consistent with a single founder. No other cases with this variant were detected among 105 simplex cases from other cities of northeastern Brazil, suggesting that this variant is confined to a geographical region. This study suggests that it is feasible to develop population-specific screening for deafness variants once causative variants are identified in different geographical groups.
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Pérdida Auditiva/genética , Miosinas/genética , Brasil , Estudios de Casos y Controles , Claudinas/genética , Análisis Mutacional de ADN , Efecto Fundador , Estudios de Asociación Genética , Predisposición Genética a la Enfermedad , Haplotipos , Humanos , Mutación MissenseRESUMEN
Hepatitis C virus (HCV) infection is a major cause of chronic liver disease and associated complications such as liver cirrhosis and hepatocellular carcinoma (HCC). Viral and host factors are known to be predictors for antiviral therapy. Host factors that are predictors of sustained viral response (SVR) were discovered by genome-wide association studies (GWAS), including single-nucleotide polymorphisms (SNPs) in or near the interferon lambda gene (rs8099917, rs12979860 and rs368234815). The aim of the present study was to verify the genotype frequencies of SNPs rs8099917, rs12979860 and rs368234815 and to evaluate the association between SNPs and the outcome of HCV infection, taking into account the population ancestry. In this study, there was an association of the three polymorphisms with both clinical outcome and response to treatment with PEG-IFN and RBV. The polymorphisms rs12979860 and rs368234815 were associated with increased sensitivity (97.7 %, 95 % CI 87.2-100, and 93.3 %, 95 % CI 81.3-98.3; respectively) and with a greater predictive value of a positive response to treatment. In multivariable analysis adjusted by gender, age and ancestry, the haplotype G/T/ΔG was related to non-response to treatment (OR = 21.09, 95 % CI 5.33-83.51; p < 0.001) and to a higher chance of developing chronic infection (OR = 5.46, 95 % CI 2.06-14.46; p = 0.001) when compared to the haplotype T/C/TT. These findings may help to adjust our treatment policies for HCV infection based on greater certainty in studies with populations with such genetic characteristics, as well as allowing us to get to know the genetic profile of our population for these polymorphisms.
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Hepatitis C Crónica/genética , Hepatitis C Crónica/inmunología , Interleucinas/genética , Adulto , Antivirales/uso terapéutico , Brasil , Femenino , Estudio de Asociación del Genoma Completo , Haplotipos , Hepatitis C Crónica/tratamiento farmacológico , Interacciones Huésped-Patógeno/genética , Interacciones Huésped-Patógeno/inmunología , Humanos , Interferón-alfa/uso terapéutico , Interferones , Masculino , Persona de Mediana Edad , Polimorfismo de Nucleótido Simple , Proteínas Recombinantes/uso terapéutico , Ribavirina/uso terapéutico , Resultado del TratamientoRESUMEN
UNLABELLED: The reference intervals for leukocytes and lymphocytes currently used by most clinical laboratories present limitations as they are primarily derived from individuals of North American and European origin. The objective this study was to determine reference values for peripheral blood B lymphocytes, T lymphocyte subsets (CD4+, CD8+, naïve, memory, regulatory, TCRαß and TCRγδ+) and NK cells from blood donors in Salvador-Bahia, Brazil. RESULTS: The proportion of included male subjects was 73.7% and the median ages of males (34) and females (35) were found to be similar. Absolute counts total lymphocytes subsets to both gender was 1,956 (1,060-4,186) cells and relative values 34%. The T CD4+ and T CD8+ lymphocytes relative values was 51% (20-62) and 24% (9-28), respectively. The most statistically significant finding observed was a higher percentage of B lymphocytes (p=0.03) in females. Commonly cited subset reference intervals were found to be consistent with values in several populations from different geographic areas.
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Linfocitos B/citología , Donantes de Sangre , Células Asesinas Naturales/citología , Subgrupos Linfocitarios/citología , Adolescente , Adulto , Brasil , Estudios Transversales , Femenino , Citometría de Flujo , Humanos , Recuento de Linfocitos , Masculino , Persona de Mediana Edad , Valores de Referencia , Adulto JovenRESUMEN
Mucopolysaccharidosis type VI (MPS VI - Maroteaux-Lamy syndrome) is a globally rare lysosomal storage disease caused by a deficiency of arylsulfatase B. However, in Monte Santo, a poor and isolated rural region in Northeast Brazil with large family sizes and high rates of community endogamy and parental consanguinity (α = 0.00483), 9 living and 4 now deceased individuals in 11 kindreds have been diagnosed with MPS VI, all with the same p.H178L missense founder mutation. A further 33 deceased persons have been identified by family members as exhibiting the disease phenotype. Detailed pedigrees were constructed for the 13 genomically confirmed MPS VI patients, with blood samples collected from 236 unaffected family members to determine the prevalence of the p.H178L mutation. A total of 98 (20.8%) mutant alleles and 374 (79.2%) normal alleles were identified, with 41.5% of the individuals heterozygous for the p.H178L mutation and 58.5% homozygous for the normal allele. A significant number of other family members with a 50 or 25% chance of being heterozygous for the p.H178L mutation were unavailable for testing. The data indicate a compelling case for community-based neonatal screening in conjunction with further initiatives among MPS VI family members to promote genetic education and genetic counselling.
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Consanguinidad , Efecto Fundador , Matrimonio/estadística & datos numéricos , Mucopolisacaridosis VI/epidemiología , Mucopolisacaridosis VI/genética , Brasil/epidemiología , Análisis Mutacional de ADN , Asesoramiento Genético/métodos , Genética de Población , Humanos , Mutación Missense/genética , Linaje , PrevalenciaRESUMEN
Considering the importance of BRCA1, BRCA2, CHEK2 and TP53 in the development of hereditary early-onset breast and ovarian cancer and that the genetic susceptibility profile of the Northeast population from Brazil has never been analyzed, this study aimed to verify the frequency of mutations of clinical significance in these genes in high-risk hereditary breast and ovarian cancer (HBOC) syndrome patients from that region. DNA samples from 106 high-risk unrelated patients mostly from Bahia, the biggest state in the Northeast region, were analyzed. These patients underwent full BRCA1 gene sequencing, screening for common founder mutations in the BRCA2, CHEK2 and TP53 genes and genetic ancestry analysis with nine ancestry informative markers. The positive results were confirmed by two sequencing reactions. Three mutations of clinical significance were found: BRCA1 p.R71G (4.71%), 3450del4 (3.77%) and TP53 p.R337H (0.94%). The genetic ancestry analysis showed a high European ancestry contribution (62.2%) as well as considerable African (31.2%) and Amerindian (6.6%) ancestry contributions (r (2)=0.991); this degree of heterogeneity was also significant in the population structure analysis (r=0.604). This population is highly admixed with a different spectrum of genetic susceptibility, with the Galician founder mutation BRCA1 p.R71G accounting for 50% of all identified mutations in high-risk HBOC patients. TP53 p.R337H was also significantly frequent; thus, the combined screening of BRCA1/2 and TP53 should be offered to high-risk HBOC patients from Northeast Brazil.
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OBJECTIVES: Suppressor of cytokine signaling 3, myxovirus resistance protein and osteopontin gene polymorphisms may influence the therapeutic response in patients with chronic hepatitis C, and an association with IL28 might increase the power to predict sustained virologic response. Our aims were to evaluate the association between myxovirus resistance protein, osteopontin and suppressor of cytokine signaling 3 gene polymorphisms in combination with IL28B and to assess the therapy response in hepatitis C patients treated with pegylated-interferon plus ribavirin. METHOD: Myxovirus resistance protein, osteopontin, suppressor of cytokine signaling 3 and IL28B polymorphisms were analyzed by PCR-restriction fragment length polymorphism, direct sequencing and real-time PCR. Ancestry was determined using genetic markers. RESULTS: We analyzed 181 individuals, including 52 who were sustained virologic responders. The protective genotype frequencies among the sustained virologic response group were as follows: the G/G suppressor of cytokine signaling 3 (rs4969170) (62.2%); T/T osteopontin (rs2853744) (60%); T/T osteopontin (rs11730582) (64.3%); and the G/T myxovirus resistance protein (rs2071430) genotype (54%). The patients who had ≥3 of the protective genotypes from the myxovirus resistance protein, the suppressor of cytokine signaling 3 and osteopontin had a greater than 90% probability of achieving a sustained response (p<0.0001). The C/C IL28B genotype was present in 58.8% of the subjects in this group. The sustained virological response rates increased to 85.7% and 91.7% by analyzing C/C IL28B with the T/T osteopontin genotype at rs11730582 and the G/G suppressor of cytokine signaling 3 genotype, respectively. Genetic ancestry analysis revealed an admixed population. CONCLUSION: Hepatitis C genotype 1 patients who were responders to interferon-based therapy had a high frequency of multiple protective polymorphisms in the myxovirus resistance protein, osteopontin and suppressor of cytokine signaling 3 genes. The combined analysis of the suppressor of cytokine signaling 3 and IL28B genotypes more effectively predicted sustained virologic response than IL28B analysis alone.
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Hepatitis C Crónica/tratamiento farmacológico , Interleucinas/genética , Proteínas de Resistencia a Mixovirus/genética , Osteopontina/genética , Polimorfismo Genético/genética , Proteínas Supresoras de la Señalización de Citocinas/genética , Adulto , Antivirales/uso terapéutico , Femenino , Frecuencia de los Genes , Marcadores Genéticos , Genotipo , Hepacivirus/efectos de los fármacos , Humanos , Interferón alfa-2 , Interferón-alfa/uso terapéutico , Interferones , Masculino , Persona de Mediana Edad , Proteínas de Resistencia a Mixovirus/efectos de los fármacos , Osteopontina/efectos de los fármacos , Polietilenglicoles/uso terapéutico , Valor Predictivo de las Pruebas , Reacción en Cadena en Tiempo Real de la Polimerasa , Proteínas Recombinantes/uso terapéutico , Ribavirina/uso terapéutico , Proteína 3 Supresora de la Señalización de Citocinas , Proteínas Supresoras de la Señalización de Citocinas/efectos de los fármacos , Resultado del TratamientoRESUMEN
OBJECTIVES: Suppressor of cytokine signaling 3, myxovirus resistance protein and osteopontin gene polymorphisms may influence the therapeutic response in patients with chronic hepatitis C, and an association with IL28 might increase the power to predict sustained virologic response. Our aims were to evaluate the association between myxovirus resistance protein, osteopontin and suppressor of cytokine signaling 3 gene polymorphisms in combination with IL28B and to assess the therapy response in hepatitis C patients treated with pegylated-interferon plus ribavirin. METHOD: Myxovirus resistance protein, osteopontin, suppressor of cytokine signaling 3 and IL28B polymorphisms were analyzed by PCR-restriction fragment length polymorphism, direct sequencing and real-time PCR. Ancestry was determined using genetic markers. RESULTS: We analyzed 181 individuals, including 52 who were sustained virologic responders. The protective genotype frequencies among the sustained virologic response group were as follows: the G/G suppressor of cytokine signaling 3 (rs4969170) (62.2%); T/T osteopontin (rs2853744) (60%); T/T osteopontin (rs11730582) (64.3%); and the G/T myxovirus resistance protein (rs2071430) genotype (54%). The patients who had ≥3 of the protective genotypes from the myxovirus resistance protein, the suppressor of cytokine signaling 3 and osteopontin had a greater than 90% probability of achieving a sustained response (p<0.0001). The C/C IL28B genotype was present in 58.8% of the subjects in this group. The sustained virological response rates increased to 85.7% and 91.7% by analyzing C/C IL28B with the T/T osteopontin genotype at rs11730582 and the G/G suppressor of cytokine signaling 3 genotype, respectively. Genetic ancestry analysis revealed an admixed population. CONCLUSION: Hepatitis C genotype 1 patients who were responders to interferon-based therapy had a high frequency of multiple protective polymorphisms in the myxovirus ...
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Adulto , Femenino , Humanos , Masculino , Persona de Mediana Edad , Hepatitis C Crónica/tratamiento farmacológico , Interleucinas/genética , Proteínas de Resistencia a Mixovirus/genética , Osteopontina/genética , Polimorfismo Genético/genética , Proteínas Supresoras de la Señalización de Citocinas/genética , Antivirales/uso terapéutico , Frecuencia de los Genes , Marcadores Genéticos , Genotipo , Hepacivirus/efectos de los fármacos , Interferón-alfa/uso terapéutico , Proteínas de Resistencia a Mixovirus/efectos de los fármacos , Osteopontina/efectos de los fármacos , Valor Predictivo de las Pruebas , Polietilenglicoles/uso terapéutico , Reacción en Cadena en Tiempo Real de la Polimerasa , Proteínas Recombinantes/uso terapéutico , Ribavirina/uso terapéutico , Proteínas Supresoras de la Señalización de Citocinas/efectos de los fármacos , Resultado del TratamientoRESUMEN
OBJECTIVE: There are many hearing impaired individuals in Monte Santo, a rural municipality in the state of Bahia, Brazil, including multiple familial cases strongly suggestive of a genetic aetiology. METHODS: The present study investigated 81 subjects with hearing impairment (HI) recruited from 36 families. Mutations often associated with HI, i.e. the DFNB1 mutations c.35delG in GJB2, deletions del(GJB6-D13S1830) and del(GJB6-D13S1854), and A1555G in the mitochondrial gene MTRNR1 were initially analyzed, with additional mutations in GJB2 identified by sequencing the coding region of the gene. RESULTS: Seven different mutations were present in GJB2 with mutations c.35delG and p.Arg75Gln, which are known to be pathogenic, identified in 37.0% of the subjects. Individuals homozygous for the c.35delG mutation were diagnosed in eight families, corresponding to 24.7% of unrelated individuals with nonsyndromic hearing impairment (NSHI), and an additional heterozygote for this mutation was present in a single family. Ten individuals (12.4%) in another family were heterozygous for the mutation p.Arg75Gln. CONCLUSIONS: Significant heterogeneity was observed in the alleles and patterns of NSHI inheritance among the subjects studied, probably due to the extensive inter-ethnic admixture that characterizes the peoples of Brazil, together with a high prevalence of community endogamy and consanguineous marriage.
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Conexinas/genética , Etnicidad/genética , Pérdida Auditiva/etnología , Pérdida Auditiva/genética , Mutación , Población Rural/estadística & datos numéricos , Adolescente , Adulto , Anciano , Brasil/epidemiología , Niño , Preescolar , Conexina 26 , Conexina 30 , Consanguinidad , Femenino , Humanos , Masculino , Persona de Mediana Edad , Receptores Nucleares Huérfanos/genética , Reacción en Cadena de la Polimerasa , Polimorfismo de Longitud del Fragmento de Restricción , Adulto JovenRESUMEN
BACKGROUND: Celiac disease is an autoimmune disorder that occurs in genetically susceptible individuals in whom the ingestion of dietary gluten induces intestinal mucosa inflammation. Previous studies suggest that celiac disease may either be very rare or underdiagnosed in African and/or African-derived population. AIM: Determine the prevalence of celiac disease in Sub-Saharan African-derived Brazilian communities using serological screening. SUBJECTS AND METHODS: Inhabitants from 10 African-derived communities from Northeastern of Brazil were screened for celiac disease. All sera were tested for endomysial class IgA antibody using indirect immunofluorescence. RESULTS: No positive test for IgA-endomysial was observed in the 860 individuals tested. CONCLUSION: Our data suggests a low prevalence of celiac disease in African-derived Brazilian populations.
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Autoanticuerpos/sangre , Población Negra , Enfermedad Celíaca/epidemiología , Adulto , Autoanticuerpos/inmunología , Enfermedades Autoinmunes/epidemiología , Enfermedades Autoinmunes/inmunología , Brasil/epidemiología , Enfermedad Celíaca/inmunología , Niño , Preescolar , Femenino , Técnica del Anticuerpo Fluorescente Indirecta , Humanos , Inmunoglobulina A/sangre , Inmunoglobulina A/inmunología , Masculino , Persona de Mediana Edad , Prevalencia , Adulto JovenRESUMEN
BACKGROUND: IL28B polymorphisms are predictors of therapy response in hepatitis C virus (HCV) patients. We do not know whether they are markers of treatment response in admixed populations or not. AIMS: To determine whether IL28B polymorphisms are predictors of therapy response in patients with HCV from an admixed population and are influenced by genetic ancestry. METHODS: rs12979860 and rs8099917 were genotyped in 222 HCV patients treated with pegylated interferon and ribavirin. Ancestry was determined using genetic markers. RESULTS: IL28B rs12979860 C/C was associated with sustained virological response (SVR), whereas C/T and T/T were associated with failure to therapy (P = 1.12 × 10(-5) ). IL28B rs8099917 T/T was associated with SVR, and G/G and G/T were associated with nonresponse/relapse (NR/R) (P = 8.00 × 10(-3) ). Among HCV genotype 1 patients with C/C genotype, genomic ancestry did not interfere with therapy response. Among patients with rs12979860 T/T genotype, African genetic contribution was greater in the NR/R group (P = 1.51 × 10(-3) ), whereas Amerindian and European genetic ancestry contribution were higher in the SVR group (P = 3.77 × 10(-3) and P = 2.16 × 10(-2) respectively). Among HCV type 1 patients with rs8099917 T/T, African genetic contribution was significantly greater in the NR/R group (P = 5.0 × 10(-3) ); Amerindian and European ancestry genetic contribution were greater in the SVR group. CONCLUSION: IL28B rs12979860 and rs8099917 polymorphisms were predictors of therapy response in HCV genotypes 1, 2 and 3 subjects from an admixed population. Genomic ancestry did not interfere with response to therapy in patients with rs12979860 C/C, whereas it interfered in patients with C/T and T/T genotypes. Among HCV genotype 1 rs8099917 T/T patients, genomic ancestry interfered with response to therapy.
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Marcadores Genéticos/genética , Hepatitis C Crónica/tratamiento farmacológico , Hepatitis C Crónica/genética , Interferón-alfa/uso terapéutico , Interleucinas/genética , Polietilenglicoles/uso terapéutico , Polimorfismo de Nucleótido Simple/genética , Ribavirina/uso terapéutico , Estudios de Casos y Controles , Femenino , Frecuencia de los Genes , Genotipo , Humanos , Interferones , Masculino , Grupos Raciales/genética , Proteínas Recombinantes/uso terapéutico , Estadísticas no Paramétricas , Resultado del Tratamiento , Carga ViralRESUMEN
Mucopolysaccharidosis type VI (MPS VI, Maroteaux-Lamy syndrome) is a lysosomal storage disease caused by deficiency of arylsulphatase B. The incidence of MPS VI is very low, usually less than 1 case for every 1,000,000 newborns. In Northeast Brazil we identified in the county of Monte Santo (52,360 inhabitants) thirteen patients with MPS VI. The aim of this work was to identify the mutation(s) present in these patients and analyze intragenic SNPs to define possible haplotypes. The 13 MPS VI patients were found to be homozygous for the p.H178L mutation. All patients have the same haplotype for the intragenic SNPs. Based on current data, the prevalence of MPS VI in this region is estimated as 1:5,000 newborns. These results, together with pedigree analysis, strongly suggest a founder effect accounting for the high frequency of p.H178L mutation in this area. This reinforces the need of a comprehensive community genetics program for this area.
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Análisis por Conglomerados , Mucopolisacaridosis IV/genética , N-Acetilgalactosamina-4-Sulfatasa/genética , Sustitución de Aminoácidos , Secuencia de Bases , Brasil/epidemiología , Análisis Mutacional de ADN , Femenino , Efecto Fundador , Estudios de Asociación Genética , Pruebas Genéticas , Homocigoto , Humanos , Masculino , Mucopolisacaridosis IV/epidemiología , Linaje , Polimorfismo de Nucleótido Simple , PrevalenciaRESUMEN
BACKGROUND: Brazilian Quilombos are Afro-derived communities founded mainly by fugitive slaves between the 16(th) and 19(th) centuries; they can be recognized today by ancestral and cultural characteristics. Each of these remnant communities, however, has its own particular history, which includes the migration of non-African derived people. METHODS: The present work presents a proposal for the origin of the male founder in Brazilian quilombos based on Y-haplogroup distribution. Y haplogroups, based on 16 binary markers (92R7, SRY2627, SRY4064, SRY10831.1 and .2, M2, M3, M09, M34, M60, M89, M213, M216, P2, P3 and YAP), were analysed for 98 DNA samples from genetically unrelated men from three rural Brazilian Afro-derived communities-Mocambo, Rio das Rãs and Kalunga-in order to estimate male geographic origin. RESULTS: Data indicated significant differences among these communities. A high frequency of non-African haplogroups was observed in all communities. CONCLUSIONS: This observation suggested an admixture process that has occurred over generations and directional mating between European males and African female slaves that must have occurred on farms before the slaves escaped. This means that the admixture occurred before the slaves escaped and the foundation of the quilombo.
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Población Negra/genética , Cromosomas Humanos Y/genética , Frecuencia de los Genes , Población Blanca/genética , Población Negra/etnología , Brasil , Femenino , Marcadores Genéticos , Variación Genética , Haplotipos , Humanos , Masculino , Problemas Sociales/etnologíaRESUMEN
O curso clínico da infecção pelo HIV é determinado por complexas interações entre características virais e o hospedeiro. Variações no hospedeiro, a exemplo das mutações CCR5Δ32 e CCR264I, são importantes para a vulnerabilidade e progressão do HIV/aids. Atualmente, observa-se um aumento do número de casos da infecção entre os segmentos da sociedade com menor nível de escolaridade e pior condição socioeconômica. Com o objetivo de estimar a ancestralidade e verificar a sua associação com renda, escolaridade vulnerabilidade e progressão ao HIV/aids foram analisados 517 indivíduos infectados pelo HIV-1, sendo 289 homens e 224 mulheres. Os pacientes foram classificados segundo a ancestralidade genômica avaliada por 10 AIMs e pela vulnerabilidade e progressão ao HIV/aids através das mutações CCR5Δ32 e CCR264I. Os indivíduos infectados pelo HIV-1 apresentaram contribuição africana de 47 por cento. As mutações CCR5Δ32 e CCR264I foram mais frequentes nos indivíduos brancos (3 por cento) e negros (18 por cento) respectivamente, e essas mutações mostraram frequência mais elevada nos tipicamente progressores (TP), quando comparados com os rapidamente progressores (RP) para aids. Não foi encontrada associação entre ancestralidade e vulnerabilidade ao HIV na análise para o grau de instrução. A pauperização da infecção pelo HIV-1 nessa população foi confirmada pela relação inversa entre renda e ancestralidade africana, pois quanto menor a renda maior a ancestralidade africana. Os resultados deste estudo sugerem associação entre as condições socioeconômicas e vulnerabilidade ao HIV/aids da população afrodescendente.
The clinical course of HIV infection is determined by complex/ interactions between viral and host's characteristics./ Host variations, such as CCR5δ32 and CCR264I mutations, are important/ to vulnerability and progression of HIV/AIDS./ Currently, the number of cases among patients with lower educational level and lower social and economic status is/ increasing./ Aiming to/ estimate the ancestry and verify its association with income,/ education, vulnerability and progression of HIV/AIDS, 517 individuals infected with HIV-1 were studied (55.9 percent men and 43.3 percent women). The/ patients were/ classified according to/ genomic ancestry evaluated by 10 AIMs and by vulnerability and/ progression of HIV/AIDS through CCR5δ32 and CCR264I mutations./ The/ individuals infected with HIV-1 showed 47 percent of African contribution./ CCR5δ32 and CCR264I mutations were more frequent in white/ (3 percent) and black (18 percent) individuals, respectively, and these same mutations/ showed higher frequency in the typically progressive HIV-infected individuals (TP), when compared to the rapidly progressive (RP)./ There was no association between ancestry and/ vulnerability to HIV in the analysis of level of education./ The pauperization of the HIV-1 infection in this population was confirmed by/ the inverse relationship between income and African ancestry, because the lower/ the income, the greater the African ancestry./ The results suggest that there is an association between socioeconomic status and vulnerability to HIV/AIDS in the Afro-descendant population.
Asunto(s)
Humanos , Masculino , Femenino , Factores Socioeconómicos , Grupos de Riesgo , Síndrome de Inmunodeficiencia Adquirida , VIH , Población NegraRESUMEN
Toxoplasma gondii is a cosmopolitan protozoan parasite of warm-blooded animals that causes high rates of infection in mammals and birds. Sparrows (Passer domesticus) are synantropic birds which are distributed worldwide. They serve as intermediate hosts for the parasite but are quite resistant to toxoplasmosis. The aims of this study were to determine the frequency of T. gondii infection in sparrows using serologic and molecular tests, and to investigate related parasites, such as Neospora caninum and Hammondia sp., using a nested PCR for Toxoplasmatinae DNA followed by sequence analysis of the PCR amplicons. A total of 293 sparrows were trapped at the states of Bahia and Pernambuco, Brazil. Tissues of 40 animals were available for molecular tests. Antibodies to T. gondii were found in 1.02% (3/293) of animals using a hemagglutination test, with titers ranging from 1:32 to 1:128. Toxoplasmatinae DNA was detected in 10/40 (25%) sparrows; after nucleotide sequencing, T. gondii was confirmed in 7/40 (17.5%) birds and N. caninum in 3/40 (7.5%) animals. Sparrows from Brazil were confirmed as intermediate hosts of T. gondii, that reinforces the potential importance of these birds on the transmission of the parasite to cats and other animals that may predate sparrows. In addition, N. caninum was detected for the first time in sparrows. To the authors' knowledge, this is the first wild synantropic bird species identified as intermediate host of N. caninum. These findings seem to have a great epidemiologic impact because of the cosmopolitan distribution of sparrows and due to their increasing population in urban and rural areas.
Asunto(s)
Enfermedades de las Aves/epidemiología , Enfermedades de las Aves/parasitología , Coccidiosis/veterinaria , Neospora/genética , Toxoplasma/genética , Toxoplasmosis Animal/epidemiología , Toxoplasmosis Animal/parasitología , Animales , Anticuerpos Antiprotozoarios/sangre , Brasil/epidemiología , Coccidiosis/diagnóstico , Coccidiosis/epidemiología , Coccidiosis/parasitología , ADN Protozoario/análisis , ADN Protozoario/genética , ADN Espaciador Ribosómico/genética , Datos de Secuencia Molecular , Reacción en Cadena de la Polimerasa , Toxoplasmosis Animal/diagnósticoRESUMEN
Neospora caninum, Hammondia sp., and Toxoplasma gondii are parasites with morphological and genetic similarities. N. caninum and T. gondii are important abortive agents of cattle and sheep, respectively, and may infect numerous animal species. Hammondia sp. is not known to induce disease in animals, but may cause confusion in the identification of closely related coccidia. The aim of this study was to investigate infection rates caused by N. caninum, Hammondia sp., and T. gondii in beef cattle using a nested PCR for Toxoplasmatinae rDNA, followed by sequencing of the PCR products. Antibodies to N. caninum and T. gondii were also investigated in the tested animals. Brains and hearts were obtained from 100 beef cattle in a slaughterhouse in Bahia. Seven samples from brain tested positive for Toxoplasmatinae DNA. No positive reactions were found in heart tissues. After sequencing of the PCR products from all positive tissues, five sequences matched with N. caninum and two matched with T. gondii. Antibodies to N. caninum and T. gondii were found in 20% and 26% of the animals, respectively. The confirmation of N. caninum and the absence of Hammondia heydorni in the tested animals is suggestive that cattle are not efficient intermediate hosts of H. heydorni; however further studies need to be performed using a greater variety of tissues and a higher sample size. The detection of T. gondii DNA in bovine tissues reinforces the potential risk of transmission of this parasite to humans and other animals through the consumption of bovine meat.