Genetic polymorphisms of CYP2B6*6, CYP2C8*3 and CYP2D6*4 in vivax malaria patients from Brazilian Amazon

Abstract Genetic variability in the host metabolism of antimalarial drugs influenced by the polymorphisms of cytochrome P450 (CYP) could lead to significant changes in antimalarial treatment response. However, little is known about the frequency of alleles CYP2B6, CYP2C8, and CYP2D6 in an Amazonian population, especially with vivax malaria. Therefore, this study aimed to determine the frequency of CYP alleles CYP2B6*6, CYP2C8*3, and CYP2D6*4 in patients with vivax malaria. The study included 231 patients with vivax malaria treated at a health care reference in Manaus, northern Brazil. A sample of peripheral blood from each subject was collected to perform DNA extraction and genotypic analysis. Genotyping of polymorphisms was performed by allelic discrimination using Real-time polymerase chain reaction. The CYP2D6*4 allele was the most prevalent among patients who developed severe malaria. The frequencies of the CYP2B6*6 and CYP2D6*4 were not different between the severe and uncomplicated malaria. There was a significant association between heterozygous CYP2D6*4 and severe cases of malaria. The results are in agreement with other reports described in the literature for different populations. Future studies are needed to understand the clinical implications of the polymorphisms in patients with vivax malaria.

Variants *1, *2, *3 and *17 of CYP2C19 Cytochrome among Helicobacter Pylori Carriers from Manaus, Amazonas State, Brazil.

OBJECTIVE: The objective of the present study was to estimate the frequency of CYP2C19 cytochrome variants *1, *2, *3 and *17 among Helicobacter pylori carriers from Manaus, Amazonas state, who were treated at Fundação de Medicina Tropical Dr. Heitor Vieira Dourado (FMT-HVD). METHODS: From the 78 recruited individuals who underwent upper gastrointestinal endoscopy with biopsy and histopathological test, 50 tested positive for H. pylori. Peripheral blood was collected from this group and CYP2C19 *2, *3 and *17 alleles were genotyped using qPCR. RESULTS: Of the 50 H. pylori + individuals, 22 were male and 28 were female. Their age varied from 18 to 67 years old, with the mean age being 40.24. Racial groups were classified by self-declaration, based on the official Instituto Brasileiro de Geografia e Estatística (IBGE) categories: 16% (8) were white, 78% (39) were brown, 4% (2) were black, and 2% (1) were indigenous. H. pylori infection was classified using the system of crosses, with 30% (15) of infections being classified as mild (+), 30% (15) as moderate (++), and 40% (20) as severe (+++). The CYP2C19 genotype results showed an allelic frequency of 11% for *2 (20% of the subjects), 6% for *3 (10% of the subjects) and 17% for *17 (30% of the subjects). Based on the phenotypic profiles, the individuals were classified as poor metabolizers (PM, 10%), intermediate metabolizers (IM, 2%), extensive metabolizers (EM, 58%) and ultra-rapid metabolizers (UM, 20%). CONCLUSIONS: Even though the percentage of allele *3 was higher than expected, the percentage of allele *17, a possible contributor to H. pylori eradication failure, was also significant. The population that self-declared as brown showed a unique genotypic pattern, unlike any other population described in previous studies. Our results show that small populations may have genetic particularities that are relevant to therapeutic outcomes.
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HTLV-2 infection in Manaus, Brazil: first description of HTLV-2c subtype in an urban area of the Western Amazon region

Abstract INTRODUCTION: We investigated the prevalence of human T-cell lymphotropic virus types 1 and 2 (HTLV-1/2) infection in patients with hematological diseases from the western Amazon region of Brazil. METHODS: Samples from 306 patients were submitted for the molecular diagnosis of HTLV-1/2 infection by real time PCR (qPCR), with amplification, sequencing, and phylogenetic analysis of the long terminal repeat (LTR) region. RESULTS: A 29-year-old male carrier of sickle cell anemia with a history of multiple blood transfusions was diagnosed with the HTLV-2c subtype. CONCLUSIONS: This study describes the first known occurrence of HTLV-2c in the urban area of Brazil's western Amazon region.

HTLV-2 infection in Manaus, Brazil: first description of HTLV-2c subtype in an urban area of the Western Amazon region.

INTRODUCTION: We investigated the prevalence of human T-cell lymphotropic virus types 1 and 2 (HTLV-1/2) infection in patients with hematological diseases from the western Amazon region of Brazil. METHODS: Samples from 306 patients were submitted for the molecular diagnosis of HTLV-1/2 infection by real time PCR (qPCR), with amplification, sequencing, and phylogenetic analysis of the long terminal repeat (LTR) region. RESULTS: A 29-year-old male carrier of sickle cell anemia with a history of multiple blood transfusions was diagnosed with the HTLV-2c subtype. CONCLUSIONS: This study describes the first known occurrence of HTLV-2c in the urban area of Brazil's western Amazon region.

Diversidade fenotípica de polimorfismos na região controladora do locus(LCR) do gene da globina beta na anemia falcifore / Phenotypic diversity of polymorphisms in the locus control region (LCR) of the beta globin gene in sickle falcifore

Os indivíduos com anemia falciforme (AF) possuem perfil clínico heterogêneo em função de fatores variados que contribuem para a modulação da doença, como a concentração de hemoglobina fetal (HbF), presença de haplótipos (HAPLO) ligados ao grupo de genes da globina beta S, talassemia alfa (TA) e mutações em genes específicos, como as localizadas nos sítios hipersensíveis a ação da DNAse I na região controladora do lócus da globina beta (LCR). O objetivo do presente estudo foi identificar subfenótipos da anemia falciforme a partir do estudo de marcadores biológicos associados aos seus portadores. As determinações hematológicas, bioquímicas e sorológicas foram realizadas na Faculdade de Farmácia da UFBA pelo uso de Kits diagnósticos e métodos automatizados. O padrão de hemoglobina foi analisado por cromatografia líquida de alto desempenho (HPLC), os haplo por PCR-RFLP e a TA por PCR. As sequências do HS-LCR foram amplificadas através da PCR e sequenciadas no ABI Prism 3100 DNA Sequencer. As análises estatísticas foram realizadas nos programas EPI INFO versão 6.04, SPSS versão 18.0 e o Prism versão 5.0. Os valores de p<0,05 foram considerados significativos para as análises realizadas. O estudo foi aprovado pelo comitê de ética em pesquisas do CPqGM-FIOCRUZ. Foram investigados 2223 indivíduos com AF, com idade entre 1-50 anos e média de 20,86 (±11,06) anos, sendo 50,70% mulheres. Valores significativos foram encontrados para os dados hematológicos e bioquímicos entre os sexos para contagem global de linfócitos nos homens (6414,85 ± 3940,70 x106/L) e mulheres (5597,81 ± 2744,24 x106/L), p= 0,003 e a contagem de reticulócitos entre os homens (7,01 ± 4,66) e mulheres (7,74 ± 5,89), p= 0,043; o colesterol de baixa densidade (LDL-c), a aspartato e alanina aminotransferases, respectivamente com p= 0,009, p= 0,029, p= 0,038 para homens e mulheres. Ao correlacionarmos eventos clínicos entre homens e mulheres, verificamos que a STA possui razão de prevalência de 1,89 para os homens (IC: 1,52-2,36, p <0,001) e de 1,59 (IC:1,06-2,39, p= 0,023) para a ocorrência de hospitalizações nesse mesmo sexo. A talassemia alfa foi realizada em 820 pacientes com 196 (23,90%) heterozigotos e 21 (2,6%) homozigotos. O total de 1872 cromossomos beta S foram estudados, sendo que os mais frequentes foram os haplótipos CAR/CAR (20,0%); Ben/Ben (25,8%) e CAR/Ben (44,2%). A correlação entre TA e dados hematológicos demonstraram resultados significativos para hemácias (Hm) (p= 0,004), volume corpuscular médio (VCM) (p= 0,015), hemoglobina corpuscular média (HCM) (p= 0,006) e plaquetas (p= 0,016) e no perfil lipídico com triglicerídeos (p= 0,001). A consulta retrospectiva aos prontuários de acompanhamento ambulatorial de 1799 pacientes com AF demonstrou que 1368 pacientes (76.04%) apresentaram pelo menos um evento vaso-oclusivo e 1475 (81.98%) tiveram pelo menos uma internação. Destes 856 (47,6%) apresentaram crise álgica; 1268 (70,5%) crises vaso-oclusivas; 115 (6,4%) Síndrome torácica aguda (STA); 53 (2,9%) dor abdominal e 24 (1,3%) dos 924 homens apresentaram priapismo. Novecentos e dezesseis (52,3%) pacientes realizaram pelo menos uma transfusão sanguínea nos dois últimos anos. O registro de infecção foi frequente em 638 (43,5%) pacientes, sendo a pneumonia a causa mais frequente, com 347 (23,6%) relatos. Cento e quinze (6,4%) pacientes foram acometidos por pelo menos um evento de AVC e 111 (6,2%) por úlcera maleolar. Quando estratificamos a idade para menor de 21 anos, a ocorrência de dactilite (síndrome mão) foi descrita em 3,5% (40) e de sequestro esplênico em 14,3% (163) nos 1141 pacientes pediátricos. A associação entre dados hematológicos.

Methylenetetrahydrofolate reductase polymorphisms in myeloid leukemia patients from Northeastern Brazil

Methylenetetrahydrofolate reductase (MTHFR: EC 1.5.1.20) polymorphisms are associated to acute lymphoid leukemia in different populations. We used the polymerase chain reaction and the restriction fragment length polymorphism method (PCR-RFLP) to investigate MTHFR C677T and A1298C polymorphism frequencies in 67 patients with chronic myeloid leukemia (CML), 27 with acute myeloid leukemia FAB subtype M3 (AML-M3) and 100 apparently healthy controls. The MTHFR mutant allele frequencies were as follows: CML = 17.2 percent for C677T, 21.6 percent for A1298C; AML-M3 = 22.2 percent for C677T, 24.1 percent for A1298C; and controls = 20.5 percent for C677T, 21 percent for A1298C. Taken together, our results provide evidence that MTHFR polymorphisms have no influence on the development of CML or AML-M3.

A novel c.197T -> A variant among Brazilian neonates with glucose-6-phosphate dehydrogenase deficiency

Glucose-6-phosphate dehydrogenase (G6PD, EC 1.1.1.49) deficiency is the most common enzyme deficiency worldwide, causing a spectrum of diseases including neonatal hyperbilirubinemia and acute or chronic hemolysis. We used the methemoglobin reduction test and G6PD electrophoresis to screen 655 neonates (354 females and 301 males) for common G6PD mutations in the city of Salvador in the Northeastern Brazilian state Bahia and found that 66 (10.1 percent) were G6PD-deficient (41 females and 25 males). The 66 (10.1 percent) G6PD-deficient neonates were assessed for the c.376 A -> G (exon 5) and c.202 G -> A (exon 4) mutations using the polymerase chain reaction and restriction enzyme fragment length polymorphism (PCR-RFLP) analysis and the results validated by DNA sequencing. Of the 66 G6PD-deficient neonates investigated we found that 54 (81.8 percent) presented the c.376 A -> G (p.Asn126Asp) and c.202 G -> A (p.Val68Met) mutations, two (3 percent) had the c.376 A -> G mutation only, two (3 percent) had the c.202 G -> A mutation only, five (7.6 percent) exhibited a previously unrecorded 197T -> A (p.Phe66Thr) substitution in exon 4 and three showed no mutations at any of these sites. Of the five neonates exhibiting the new 197T -> A (p.Phe66Thr) substitution, four (6.1 percent) also presented the c.202 G -> A and c.376 A -> G mutations and one (1.5 percent) had the c.[197T -> A / 202 G -> A] combination. We propose to name the new variant G6PD Bahia.

Polymorphisms in the glutathione S-transferase theta and mu genes and susceptibility to myeloid leukemia in Brazilian patients

The null genotype for glutathione S-transferase (GST, EC 2.5.1.18) gene polymorphisms is considered a risk factor for leukemia in different populations. In this work we investigated the GSTT1 and GSTM1 polymorphisms using multiplex PCR in 53 patients with chronic myeloid leukemia (CML), 23 with acute promyelocytic leukemia (APL) and 304 apparently healthy controls. In this association study we found that the GSTT1null genotype was more frequent in our group of APL patients than in the control group [OR = 2.75 (95 percent CI = 1.10-6.88)], providing evidence that a deletion in the GSTT1 gene could be a risk factor for this type of leukemia.

Hemoglobinopathies in newborns from Salvador, Bahia, Northeast Brazil.

Hemoglobinopathies are hereditary disorders of the hemoglobin molecule with a high prevalence worldwide. Brazil has a prevalence of 0.1 to 0.3% of newborns with sickle cell anemia and 20.0 to 25.0% of heterozygous alpha2 thalassemia among African Brazilians. In the present study, we investigated the presence of variant hemoglobins and alpha2(3.7 Kb) and alpha2 (4.2 Kb) thalassemia in newborns from Salvador, Bahia, Brazil. Samples of umbilical cord blood from a total of 590 newborns were analyzed, of which 57 (9.8%) were FAS; 36 (6.5%) FAC; one (0.2%) SF; and five (0.9%) FSC. One hundred fourteen (22.2%) newborns had alpha2(3.7 Kb) thalassemia, of whom 101 (19.7%) were heterozygous and 13 (2.5%) homozygous, showing statistical significance for hematological data between newborns with normal alpha genes and alpha2(3.7 Kb) thalassemia carriers. The alpha2(4.2 Kb) thalassemia was not found. Frequencies found in the present study confirm that hemoglobinopathies are a public health problem in Brazil, emphasizing the need for neonatal screening and genetic counseling programs.

Hemoglobinopathies in newborns from Salvador, Bahia, Northeast Brazil

Hemoglobinopatias são alterações hereditárias na molécula de hemoglobina com prevalência mundial elevada. O Brasil apresenta prevalência de 0,1 a 0,3por cento para recém-nascidos com anemia falciforme e freqüência de 20,0 a 25,0 por cento para a ocorrência de heterozigotos da talassemia alfa sobrescrito 2 entre indivíduos afro-descendentes. O presente estudo investigou a presença de hemoglobinas variantes e talassemia alfa 2 subscrito 2 sobrescrito 3.7kb e alfa subscrito 2 sobrescrito 4.2Kb em recém-nascidos de Salvador, Bahia, Brasil. Analisamos o sangue do cordão umbilical de 590 recém-nascidos, sendo 57 (9,8 por cento) com padrão FAS; 36 (6,5 por cento) FAC; um (0,2 por cento) SF e cinco (0,9 por cento) FSC. Cento e catorze (22,2 por cento) apresentaram talassemia alfa 2 subscrito 2 sobrescrito 3.7kb, dos quais 101 (19,7 por cento) foram heterozigotos e 13 (2,5 por cento) homozigotos, mostrando significância estatística para os dados hematológicos entre recém-nascidos com genes a normais e portadores de talassemia alfa 2 subscrito 2 sobrescrito 3.7kb. A talassemia alfa subscrito 2 sobrescrito 4.2Kb não foi encontrada. As freqüências descritas neste trabalho confirmam que as hemoglobinopatias são um problema de Saúde Pública no Brasil, enfatizando a importância dos programas de triagem neonatal e aconselhamento genético.