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1.
Viruses ; 16(3)2024 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-38543725

RESUMO

Coronavirus disease 2019 (COVID-19) is an infection caused by SARS-CoV-2. Genome-wide association studies (GWASs) have suggested a strong association of genetic factors with the severity of the disease. However, many of these studies have been completed in European populations, and little is known about the genetic variability of indigenous peoples' underlying infection by SARS-CoV-2. The objective of the study is to investigate genetic variants present in the genes AQP3, ARHGAP27, ELF5L, IFNAR2, LIMD1, OAS1 and UPK1A, selected due to their association with the severity of COVID-19, in a sample of indigenous people from the Brazilian Amazon in order to describe potential new and already studied variants. We performed the complete sequencing of the exome of 64 healthy indigenous people from the Brazilian Amazon. The allele frequency data of the population were compared with data from other continental populations. A total of 66 variants present in the seven genes studied were identified, including a variant with a high impact on the ARHGAP27 gene (rs201721078) and three new variants located in the Amazon Indigenous populations (INDG) present in the AQP3, IFNAR2 and LIMD1 genes, with low, moderate and modifier impact, respectively.


Assuntos
COVID-19 , Humanos , COVID-19/epidemiologia , COVID-19/genética , SARS-CoV-2/genética , Estudo de Associação Genômica Ampla , Frequência do Gene , Povos Indígenas/genética , Peptídeos e Proteínas de Sinalização Intracelular , Proteínas com Domínio LIM
2.
Sci Total Environ ; 923: 171232, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38402986

RESUMO

Studies have identified elevated levels of mercury in Amazonian Indigenous individuals, highlighting them as one of the most exposed to risks. In the unique context of the Brazilian Indigenous population, it is crucial to identify genetic variants with clinical significance to better understand vulnerability to mercury and its adverse effects. Currently, there is a lack of research on the broader genomic profile of Indigenous people, particularly those from the Amazon region, concerning mercury contamination. Therefore, the aim of this study was to assess the genomic profile related to the processes of mercury absorption, distribution, metabolism, and excretion in 64 Indigenous individuals from the Brazilian Amazon. We aimed to determine whether these individuals exhibit a higher susceptibility to mercury exposure. Our study identified three high-impact variants (GSTA1 rs1051775, GSTM1 rs1183423000, and rs1241704212), with the latter two showing a higher frequency in the study population compared to global populations. Additionally, we discovered seven new variants with modifier impact and a genomic profile different from the worldwide populations. These genetic variants may predispose the study population to more harmful mercury exposure compared to global populations. As the first study to analyze broader genomics of mercury metabolism pathways in Brazilian Amazonian Amerindians, we emphasize that our research aims to contribute to public policies by utilizing genomic investigation as a method to identify populations with a heightened susceptibility to mercury exposure.


Assuntos
Mercúrio , Humanos , Mercúrio/análise , Indígenas Sul-Americanos/genética , Povos Indígenas , Genômica , Brasil
3.
J Pers Med ; 13(9)2023 Sep 08.
Artigo em Inglês | MEDLINE | ID: mdl-37763132

RESUMO

Gastric Cancer is a disease associated with environmental and genetic changes, becoming one of the most prevalent cancers around the world and with a high incidence in Brazil. However, despite being a highly studied neoplastic type, few efforts are aimed at populations with a unique background and genetic profile, such as the indigenous peoples of the Brazilian Amazon. Our study characterized the molecular profile of five genes associated with the risk of developing gastric cancer by sequencing the complete exome of 64 indigenous individuals belonging to 12 different indigenous populations in the Amazon. The analysis of the five genes found a total of 207 variants, of which 15 are new in our indigenous population, and among these are two with predicted high impact, present in the TTN and CDH1 genes. In addition, at least 20 variants showed a significant difference in the indigenous population in comparison with other world populations, and three are already associatively related to some type of cancer. Our study reaffirms the unique genetic profile of the indigenous population of the Brazilian Amazon and allows us to contribute to the conception of early diagnosis of complex diseases such as cancer, improving the quality of life of individuals potentially suffering from the disease.

4.
J Pers Med ; 12(12)2022 Dec 13.
Artigo em Inglês | MEDLINE | ID: mdl-36556273

RESUMO

The mucin (MUC) family includes several genes aberrantly expressed in multiple carcinomas and mediates diverse pathways essentials for oncogenesis, in both solid and hematological malignancies. Acute Lymphoblastic Leukemia (ALL) can have its course influenced by genetic variants, and it seems more frequent in the Amerindian population, which has been understudied. Therefore, the present work aimed to investigate the MUC family exome in Amerindian individuals from the Brazilian Amazon, in a sample containing healthy Native Americans (NAMs) and indigenous subjects with ALL, comparing the frequency of polymorphisms between these two groups. The population was composed of 64 Amerindians from the Brazilian Amazon, from 12 different isolated tribes, five of whom were diagnosed with ALL. We analyzed 16 genes from the MUC family and found a total of 1858 variants. We compared the frequency of each variant in the ALL vs. NAM group, which led to 77 variants with a significant difference and, among these, we excluded those with a low impact, resulting in 63 variants, which were distributed in nine genes, concentrated especially in MUC 19 (n = 30) and MUC 3A (n = 18). Finally, 11 new variants were found in the NAM population. This is the first work with a sample of native Americans with cancer, a population which is susceptible to ALL, but remains understudied. The MUC family seems to have an influence on the development of ALL in the Amerindian population and especially MUC19 and MUC3A are shown as possible hotspots. In addition, the 11 new variants found point to the need to have their clinical impact analyzed.

5.
J Pers Med ; 12(6)2022 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-35743738

RESUMO

Given the role of pharmacogenomics in the large variability observed in drug efficacy/safety, an assessment about the pharmacogenomic profile of patients prior to drug prescription or dose adjustment is paramount to improve adherence to treatment and prevent adverse drug reaction events. A population commonly underrepresented in pharmacogenomic studies is the Native American populations, which have a unique genetic profile due to a long process of geographic isolation and other genetic and evolutionary processes. Here, we describe the pharmacogenetic variability of Native American populations regarding 160 pharmacogenes involved in absorption, distribution, metabolism, and excretion processes and biological pathways of different therapies. Data were obtained through complete exome sequencing of individuals from 12 different Amerindian groups of the Brazilian Amazon. The study reports a total of 3311 variants; of this, 167 are exclusive to Amerindian populations, and 1183 are located in coding regions. Among these new variants, we found non-synonymous coding variants in the DPYD and the IFNL4 genes and variants with high allelic frequencies in intronic regions of the MTHFR, TYMS, GSTT1, and CYP2D6 genes. Additionally, 332 variants with either high or moderate (disruptive or non-disruptive impact in protein effectiveness, respectively) significance were found with a minimum of 1% frequency in the Amazonian Amerindian population. The data reported here serve as scientific basis for future design of specific treatment protocols for Amazonian Amerindian populations as well as for populations admixed with them, such as the Northern Brazilian population.

6.
J Pers Med ; 12(4)2022 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-35455670

RESUMO

Genetic factors associated with COVID-19 disease outcomes are poorly understood. This study aimed to associate genetic variants in the SLC6A20, LZTFL1, CCR9, FYCO1, CXCR6, XCR1, and ABO genes with the risk of severe forms of COVID-19 in Amazonian Native Americans, and to compare the frequencies with continental populations. The study population was composed of 64 Amerindians from the Amazon region of northern Brazil. The difference in frequencies between the populations was analyzed using Fisher's exact test, and the results were significant when p ≤ 0.05. We investigated 64 polymorphisms in 7 genes; we studied 47 genetic variants that were new or had impact predictions of high, moderate, or modifier. We identified 15 polymorphisms with moderate impact prediction in 4 genes (ABO, CXCR6, FYCO1, and SLC6A20). Among the variants analyzed, 18 showed significant differences in allele frequency in the NAM population when compared to others. We reported two new genetic variants with modifier impact in the Amazonian population that could be studied to validate the possible associations with COVID-19 outcomes. The genomic profile of Amazonian Native Americans may be associated with protection from severe forms of COVID-19. This work provides genomic data that may help forthcoming studies to improve COVID-19 outcomes.

7.
Genes (Basel) ; 13(4)2022 03 30.
Artigo em Inglês | MEDLINE | ID: mdl-35456428

RESUMO

BACKGROUND: Prostate cancer represents 3.8% of cancer deaths worldwide. For most prostate cancer cells to grow, androgens need to bind to a cellular protein called the androgen receptor (AR). This study aims to demonstrate the expression of five microRNAs (miRs) and its influence on the AR formation in patients from the northern region of Brazil. MATERIAL AND METHODS: Eighty-four tissue samples were investigated, including nodular prostatic hyperplasia (NPH) and acinar prostatic adenocarcinoma (CaP). Five miRs (27a-3p, 124, 130a, 488-3p, and 506) were quantified using the TaqMan® Real Time PCR method and AR was measured using Western blotting. RESULTS: Levels of miRs 124, 130a, 488-3p, and 506 were higher in NPH samples. Conversely, in the CaP cases, higher levels of miR 27a-3p and AR were observed. CONCLUSION: In the future, these microRNAs may be tested as markers of CaP at the serum level. The relative expression of AR was 20% higher in patients with prostate cancer, which suggests its potential as a biomarker for prostate malignancy.


Assuntos
Adenocarcinoma , MicroRNAs , Neoplasias da Próstata , Adenocarcinoma/genética , Androgênios , Linhagem Celular Tumoral , Humanos , Masculino , MicroRNAs/metabolismo , Próstata/patologia , Neoplasias da Próstata/patologia
8.
J Pers Med ; 12(3)2022 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-35330370

RESUMO

Acute lymphoblastic leukemia (ALL) is the most common cancer during childhood, representing about 30-35% of cases. Its etiology is complex and not fully understood. ALL is influenced by genetic variants, and their frequencies (Fq) vary in different ethnic groups, which consequently could influence the epidemiology of this cancer worldwide. The aim of this study was to investigate the correlation between the genetic variants and their impacts on incidence (IC), mortality (MT), and prevalence (PV) rates of ALL in different world populations. METHODS: Sixty variants were selected from the literature with Genome Wide Association studies (GWAS). Information regarding allele Fq was selected from the 1000 Genomes platform. Epidemiological data were taken from the Global Burden of disease visualisations (GBD) Compare website. Statistical analyses were calculated in RStudio v.3.5.1 software. RESULTS: Four variants demonstrated significant results in correlations with epidemiological data for ALL. The PAX5 gene variant (rs2297105) had an indirect relationship with PV and IC of ALL, showing that an increased Fq of this variant is related to low rates of both. An increased Fq of rs915172 in EPB4IL2 gene was also correlated with a lower IC of ALL. The rs1048943 of the CYP1A1 gene and the rs3088440 polymorphism of the CDKN2A gene were shown to have a direct proportional relationship with MT rate, showing that an increased Fq of these variants correlates with a worse prognosis worldwide. CONCLUSION: Our study points out four important variants for understanding the IC, PV, and MT rates for ALL. The ascertainment of these data may help to choose molecular markers to investigate the susceptibility and prognosis of ALL.

9.
Cancer Chemother Pharmacol ; 88(5): 837-844, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34331561

RESUMO

PURPOSE: Fluoropyrimidines are one of the most used drug class to treat cancer patients, although they show high levels of associated toxicity. This study analyzed 33 polymorphisms in 17 pharmacogenes involved with the pharmacogenomics of fluoropyrimidines, in gastrointestinal cancer patients undergoing fluoropyrimidine-based treatment in the Brazilian Amazon. METHODS: The study population was composed of 216 patients, 92 of whom have an anatomopathological diagnosis of gastric cancer and 124 of colorectal cancer. The single nucleotide polymorphisms (SNP) were genotyped by allelic discrimination using the TaqMan OpenArray Genotyping technology, with a panel of 32 customized assays, run in a QuantStudio ™ 12K Flex Real-Time PCR System (Applied Biosystems, Life Technologies, Carlsbad USA). Ancestry analysis was performed using 61 autosomal ancestry informative markers (AIMs). RESULTS: The study population show mean values of 48.1% European, 31.1% Amerindian, and 20.8% African ancestries. A significant risk association for general and severe toxicity was found in the rs4451422 of FPGS (p = 0.001; OR 3.40; CI 95% 1.65-7.00 and p = 0.006; OR 4.63; CI 95% 1.56-13.72, respectively) and the rs9524885 of ABCC4 (p = 0.023; OR 2.74; CI 95% 1.14-6.65 and p = 0.024; OR 5.36; IC 95% 1.24-23.11, respectively) genes. The rs760370 in the SLC29A1 gene (p = 0.009; OR 6.71; CI 95% 1.16-8.21) and the rs1801133 in the MTHFR toxicity (p = 0.023; OR 3.09; CI 95% 1.16-8.21) gene also demonstrated to be significant, although only for severe toxicity. The results found in this study did not have statistics analysis correction. CONCLUSION: Four polymorphisms of the ABCC4, FPGS, SLC29A1, and MTHFR genes are likely to be potential predictive biomarkers for precision medicine in fluoropyrimidine-based treatments in the population of the Brazilian Amazon, which is constituted by a unique genetic background.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Neoplasias Gastrointestinais/tratamento farmacológico , Neoplasias Gastrointestinais/genética , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Brasil , Camptotecina/análogos & derivados , Camptotecina/farmacologia , Transportador Equilibrativo 1 de Nucleosídeo/genética , Feminino , Fluoruracila/administração & dosagem , Fluoruracila/farmacocinética , Fluoruracila/farmacologia , Humanos , Leucovorina/farmacologia , Masculino , Metilenotetra-Hidrofolato Redutase (NADPH2)/genética , Pessoa de Meia-Idade , Proteínas Associadas à Resistência a Múltiplos Medicamentos/genética , Compostos Organoplatínicos/farmacologia , Peptídeo Sintases/genética , Variantes Farmacogenômicos , Polimorfismo de Nucleotídeo Único
10.
Heliyon ; 7(6): e07379, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-34179542

RESUMO

The COVID-19 pandemic has infected over 25 million of people worldwide, 5% of whom evolved to death and, among of the active cases, more than 60 thousand are classified as critical or severe. Recent studies revealed that ApoE, a protein encoded by APOE gene, may increase the risk of severe COVID-19 cases. ApoE has been involved with prevention of tissue damage and promotion of adaptative immune response in the lungs. This study investigated frequencies distribution of alleles that alter the ApoE expression in lung tissues to trace a profile of these variants and associate them to COVID-19 clinical outcomes. Data about APOE expression levels was obtained from the Genotype-Tissue Expression Project and the allele frequencies of APOE variants was acquired from the populations included in the phase 3 release of the 1000 Genomes Project. A total of 128 variants showed a significant impact on the APOE expression in lung tissues (p < 0.0001). Linkage Disequilibrium analysis revealed that 98 variants were closely grouped into seven distinct haplotype blocks, of which six were composed of variants that significantly decrease APOE gene expression in the lungs. Most of the haplotypes with higher impact on APOE expression showed greater frequencies in Europeans and lower in Africans, which implies that European populations might be more susceptible to SARS-CoV-2 infection. The present study indicates a potential genetic contribution of APOE expression-modifying variants in modulating the prognosis of COVID-19.

11.
Pharmgenomics Pers Med ; 14: 117-133, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33519226

RESUMO

INTRODUCTION: The genetic admixture of the Brazilian population has considerable relevance to the implementation of the principles of pharmacogenomics (PGx), as it may compromise the extrapolation of data obtained in more homogeneous world populations. PURPOSE: This study aims to investigate a panel of 117 polymorphisms in 35 pharmacogenes, which contains label recommendations or clinical evidence by international drug regulatory agencies, in Amazonian Native American populations, and compare the results obtained with continental population data from the 1000 Genomes Project Consortium. PATIENTS AND METHODS: The study population is composed of 109 Native American individuals from three Brazilian Amazon groups. The genotyping of the PGx polymorphisms was performed by allelic discrimination using TaqMan® OpenArray Genotyping with a panel of 120 customized assays on the QuantStudio™ 12K Flex Real-Time PCR System. RESULTS: Statistical differences within the Native American populations were observed regarding both genotypes and phenotypes of some genes of the CYP family. The discriminant analysis of principal components (DAPCs) between the NAM group and the continental populations of the 1000 Genomes Project resulted in the clustering of the three Native American populations. Additionally, in general, the NAM group was determined to be closely situated between East Asia, America, and South Asia groups, which enabled us to infer a genetic similarity between these populations. The DAPC analysis further demonstrated that eight polymorphisms and six polymorphisms were more relevant in differentiating the NAM from the continental populations and the NAM populations among themselves, respectively. CONCLUSION: Some investigated polymorphisms show differences among world populations, particularly with populations of European origin, for whom precision medicine protocols are primarily designed. The accumulated knowledge regarding these variations may assist in the design of specific protocols for Native American populations and populations admixed with them.

12.
Genes (Basel) ; 12(2)2021 01 22.
Artigo em Inglês | MEDLINE | ID: mdl-33499154

RESUMO

Estimates show that 5-10% of breast cancer cases are hereditary, caused by genetic variants in autosomal dominant genes; of these, 16% are due to germline mutations in the BRCA1 and BRCA2 genes. The comprehension of the mutation profile of these genes in the Brazilian population, particularly in Amazonian Amerindian groups, is scarce. We investigated fifteen polymorphisms in the BRCA1 and BRCA2 genes in Amazonian Amerindians and compared the results with the findings of global populations publicly available in the 1000 Genomes Project database. Our study shows that three variants (rs11571769, rs144848, and rs11571707) of the BRCA2 gene, commonly associated with hereditary breast cancer, had a significantly higher allele frequency in the Amazonian Amerindian individuals in comparison with the African, American, European, and Asian groups analyzed. These data outline the singular genetic profiles of the indigenous population from the Brazilian Amazon region. The knowledge about BRCA1 and BRCA2 variants is critical to establish public policies for hereditary breast cancer screening in Amerindian groups and populations admixed with them, such as the Brazilian population.


Assuntos
Alelos , Proteína BRCA2/genética , Neoplasias da Mama/epidemiologia , Neoplasias da Mama/genética , Mutação , Proteína BRCA1 , Brasil/epidemiologia , Frequência do Gene , Predisposição Genética para Doença , Genótipo , Mutação em Linhagem Germinativa , Humanos , Grupos Populacionais/genética
13.
Am J Transl Res ; 12(10): 6626-6636, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33194059

RESUMO

Colorectal (CRC) and gastric (GC) cancers are associated with increased morbidity and mortality. Single nucleotide polymorphisms (SNPs) of xenobiotic metabolism and transporter genes may play a role in the individual responses to exposure to substances implicated in susceptibility to cancer. The investigation of the genetic variation related to the activation and detoxification of xenobiotics may thus help to clarify the prevalence of neoplasms. We analyzed the role of 30 SNPs in xenobiotic-metabolizing and transporter genes in susceptibility to CRC and GC. The study included individuals diagnosed with CRC (n = 121) and GC (n = 95), and 141 controls (non-cancer patients) from the population of Belém, in the Brazilian Amazon. The results indicated an association between the polymorphisms rs2231142 (P = 0.013; OR = 3.01; 95% CI = 1.26-7.13), in the ABCG2 gene, and rs1801159 (P = 0.03; OR = 2.35; 95% CI = 1.14-5.05), in DPYD gene, with the risk of developing GC. The polymorphism rs17116806 of the DPYD gene was found to be associated with a lower risk of developing gastric (P≤0.0001; OR = 0.043; 95% CI = 0.015-0.12) or colorectal (P≤0.0001; OR = 0.076; 95% CI = 0.33-0.18) cancers, indicating that the same variant may play a similar role in different types of cancer tissue. Additionally, the carriers of the TT genotype of the polymorphism in the ABCB1 gene (rs1128503) presented a reduced probability of developing CRC (P = 0.0001; OR = 0.16; 95% CI = 0.06-0.41) as well as GC (P = 0.007; OR = 0.27; 95% CI = 0.1-0.7). Our findings indicate that polymorphisms in xenobiotic-metabolizing and transporter genes may modulate susceptibility to colorectal and gastric cancers.

14.
PLoS One ; 15(7): e0236033, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32673332

RESUMO

In recent years, the incidence of tuberculosis (TB) has declined worldwide, although this disease still occurs at relatively high rates in Amerindian populations. This suggests that the genetic ancestry of Amerindians may be an important factor in the development of infections, and may account for at least some of the variation in infection rates in the different populations. The present study investigated the potential influence of Amerindian genetic ancestry on susceptibility to tuberculosis in an Amazon population. The study included 280 patients diagnosed with tuberculosis and 138 asymptomatic hospital employees with no history of TB, but who were in contact with bacterially active TB patients. Ancestry analysis was run on a set of 61 Ancestry-Informative Markers to estimate European, African, and Amerindian genetic ancestry using STRUCTURE v2.2. The TB group had significantly higher Amerindian ancestry in comparison with the control group, and significantly lower European ancestry. Amerindian ancestry in the 20-60% range was found to be the principal risk factor for increased susceptibility to TB. The results of the study indicate that Amerindian ancestry is an important risk factor for susceptibility to TB in the admixed population of the Brazilian Amazon region.


Assuntos
População Negra/estatística & dados numéricos , Variação Genética , Genética Populacional , Indígenas Sul-Americanos/estatística & dados numéricos , Mycobacterium tuberculosis/genética , Tuberculose/epidemiologia , População Branca/estatística & dados numéricos , Brasil/epidemiologia , Estudos de Casos e Controles , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Tuberculose/genética , Tuberculose/microbiologia
15.
Sci Rep ; 10(1): 10292, 2020 06 24.
Artigo em Inglês | MEDLINE | ID: mdl-32581388

RESUMO

Acute Lymphoblastic Leukemia (ALL) is the most common cancer in children. Differences are found among ethnic groups in the results of the treatment of pediatric ALL. In general, children with a high level of native American ancestry tend to respond less positively to ALL treatments, which may be related to specific genomic variants found in native American groups. Despite the evidence, few data are available on the distribution of the pharmacogenomic variants relevant to the treatment of ALL in traditional Amerindian populations, such the those of the Amazon region. Given this, the present study investigated 27 molecular markers related to the treatment of ALL in Amerindians from Brazilian Amazonia and compared the frequencies with those recorded previously on five continents, that are available in the 1,000 Genomes database. The variation in the genotype frequencies among populations was evaluated using Fisher's exact test. The False Discovery Rate method was used to correct the results of the multiple analyses. Significant differences were found in the frequencies of the majority of markers between the Amerindian populations and those of other regions around the world. These findings highlight the unique genetic profile of the indigenous population of Brazilian Amazonia, which may reflect a distinct therapeutic profile for the treatment of ALL in these populations.


Assuntos
Antineoplásicos/farmacologia , Indígenas Sul-Americanos/genética , Variantes Farmacogenômicos , Leucemia-Linfoma Linfoblástico de Células Precursoras/tratamento farmacológico , Antineoplásicos/uso terapêutico , Brasil , Criança , Pré-Escolar , Feminino , Marcadores Genéticos , Humanos , Masculino , Leucemia-Linfoma Linfoblástico de Células Precursoras/genética
16.
PLoS One ; 15(4): e0231651, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32294118

RESUMO

INTRODUCTION: The nudix hydrolase 15 (NUDT15) gene acts in the metabolism of thiopurine, by catabolizing its active metabolite thioguanosine triphosphate into its inactivated form, thioguanosine monophosphate. The frequency of alternative NUDT15 alleles, in particular those that cause a drastic loss of gene function, varies widely among geographically distinct populations. In the general population of northern Brazilian, high toxicity rates (65%) have been recorded in patients treated with the standard protocol for acute lymphoblastic leukemia, which involves thiopurine-based drugs. The present study characterized the molecular profile of the coding region of the NUDT15 gene in two groups, non-admixed Amerindians and admixed individuals from the Amazon region of northern Brazil. METHODS: The entire NUDT15 gene was sequenced in 64 Amerindians from 12 Amazonian groups and 82 admixed individuals from northern Brazil. The DNA was extracted using phenol-chloroform. The exome libraries were prepared using the Nextera Rapid Capture Exome (Illumina) and SureSelect Human All Exon V6 (Agilent) kits. The allelic variants were annotated in the ViVa® (Viewer of Variants) software. RESULTS: Four NUDT15 variants were identified: rs374594155, rs1272632214, rs147390019, andrs116855232. The variants rs1272632214 and rs116855232 were in complete linkage disequilibrium, and were assigned to the NUDT15*2 genotype. These variants had high frequencies in both our study populations in comparison with other populations catalogued in the 1000 Genomes database. We also identified the NUDT15*4 haplotype in our study populations, at frequencies similar to those reported in other populations from around the world. CONCLUSION: Our findings indicate that Amerindian and admixed populations from northern Brazil have high frequencies of the NUDT15 haplotypes that alter the metabolism profile of thiopurines.


Assuntos
Povos Indígenas/genética , Pirofosfatases/genética , Antimetabólitos Antineoplásicos/farmacologia , Antimetabólitos Antineoplásicos/uso terapêutico , Brasil , Humanos , Mercaptopurina/farmacologia , Mercaptopurina/uso terapêutico , Polimorfismo de Nucleotídeo Único , Leucemia-Linfoma Linfoblástico de Células Precursoras/tratamento farmacológico , Pirofosfatases/metabolismo
17.
Am J Transl Res ; 12(12): 8216-8224, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33437394

RESUMO

Acute Lymphoblastic Leukemia (ALL) is the most common type of cancer in children. Polymorphisms that alter the normal function of the microRNAs involved in the development of ALL have been widely investigated, although published data on these polymorphisms in admixed populations are scarce. We investigated the role of 10 polymorphisms in the microRNA and protein-coding genes of the microRNA synthesis complex in susceptibility to pediatric B-cell ALL. The study includes 100 pediatric ALL patients and 180 healthy individuals. The statistical analyses were run in SPSS v.25.0. In the case of the microRNA synthesizing genes, a significant pattern was found in only gene, that is, the rs3805500 polymorphism of DROSHA, in which the homozygous mutant (AA) genotype was associated with a threefold increase in the risk of developing ALL when compared to other genotypes (P=0.004, OR=2.913, CI=1.415-5.998). In the microRNA coding genes, the homozygous mutant rs3746444 genotype of the MIR499A gene was associated with a 17-fold increase in the risk of development of ALL (P<0.001, OR=17.797, CI=5.55-57.016). A protective effect against the development of ALL was also observed in the carriers of the wild homozygous rs2505901 genotype in the MIR938 gene. Our findings highlight the potential of these polymorphisms in the genes involving in the coding of microRNAs for the evaluation of the risk of contracting ALL in the population of the Brazilian Amazon region. These findings contribute to a more complete understanding of the complex etiology of ALL.

18.
Sci Rep ; 9(1): 7201, 2019 05 10.
Artigo em Inglês | MEDLINE | ID: mdl-31076604

RESUMO

The variation in the allelic frequencies of polymorphic pharmacogenes among different ethnic groups may be responsible for severe adverse reactions to or altered efficacy of a wide variety of drugs. Amazonian Amerindian populations have a unique genetic profile that may have a fundamental on the efficacy and safety of certain drugs. The genetic characteristics of these populations are poorly known, which can negatively impact the systematic application of treatments guided by pharmacogenomic guidelines. We investigated the diversity of 32 polymorphisms in genes responsible for drug Absorption, Distribution, Metabolism and Excretion (ADME) in Amazonian Amerindians, and compared the findings with populations from other continents available in the 1000 Genomes database. We found significantly different (P ≤ 1.56E-03) allelic frequencies and genotype distributions in many study markers in comparison with African, European, American and Asian populations. Based on FST values, the Amerindian population was also the most distinct (mean FST = 0.09917). These data highlight the unique genetic profile of the indigenous population from the Brazilian Amazon region, which is potentially important from a pharmacogenetic viewpoint. Understanding the diversity of ADME- related genetic markers is crucial to the implementation of individualized pharmacogenomic treatment protocols in Amerindian populations, as well as populations with a high degree of admixture with this ethnic group, such as the general Brazilian population.


Assuntos
Técnicas de Genotipagem/métodos , Indígenas Sul-Americanos/genética , Variantes Farmacogenômicos , Brasil/etnologia , Frequência do Gene , Genética Populacional , Humanos , Polimorfismo de Nucleotídeo Único
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