Fourteen-year trends in overweight, general obesity, and abdominal obesity in Amazonian indigenous peoples.

BACKGROUND: Available data show that the epidemiological profile of most indigenous Brazilian populations is characterized by the coexistence of long-standing health problems (high prevalence of infectious and parasitic diseases, malnutrition, and deficiency diseases, such as anemia in children and women of reproductive age), associated with new health problems, especially those related to obesity (hypertension, type 2 diabetes mellitus and dyslipidemia). Based on this scenario, this study analyzed the nutritional profile of the adult population of seven indigenous peoples from the Brazilian Amazon in the years 2007 and 2021. METHODS: A total of 598 adults individuals were analyzed in 2007 (319 women and 279 men) and 924 in 2021 (483 women and 441 men), from seven indigenous peoples located in the state of Pará, who were assisted during health actions carried out in 2007 and in 2021. Body mass index classification used the World Health Organization criteria for adults: low weight, < 18.5 kg/m2; normal weight, ≥ 18.5 and < 25 kg/m2); overweight, ≥ 25 and < 30 kg/m2, and obesity, ≥ 30 kg/m2. A waist circumference (WC) < 90 cm in men and < 80 cm in women was considered normal. RESULTS: The data revealed heterogeneous anthropometric profiles, with a low prevalence of nutritional changes in the Araweté, Arara and Parakanã peoples, and high proportions of excess weight and abdominal obesity in the Kararaô, Xikrin do Bacajá, Asurini do Xingu and Gavião peoples, similar to or even higher than the national averages. CONCLUSION: Different stages of nutritional transition were identified in the indigenous peoples analyzed, despite apparently having been subjected to the same environmental pressures that shaped their nutritional profile in recent decades, which may indicate different genetic susceptibilities to nutritional changes. The evidence shown in this study strongly suggests the need to investigate in greater depth the genetic and environmental factors associated with the nutritional profile of Brazilian indigenous peoples, with assessment of diet, physical activity and sociodemographic and socioeconomic variables that enable the development of appropriate prevention and monitoring measures.

CCR5∆32 and SDF1 3'A: Gene Variants, Expression and Influence on Biological Markers for the Clinical Progression to AIDS among HIV-1 Virus Controllers in a Mixed Population of the Amazon Region of Brazil.

CCR5Δ32 and SDF1-3'A polymorphisms were investigated in a cohort of viremia controllers, without the use of therapy, along with their influence on CD4+ T lymphocytes (TLs), CD8+ TLs, and plasma viral load (VL). The samples were analyzed from 32 HIV-1-infected individuals classified as viremia controllers 1 and 2 and viremia non-controllers, from both sexes, mostly heterosexuals, paired with 300 individuals from a control group. CCR5∆32 polymorphism was identified by PCR amplification of a fragment of 189 bp for the wild-type allele and 157 bp for the allele with the ∆32 deletion. SDF1-3'A polymorphism was identified by PCR, followed by enzymatic digestion (restriction fragment length polymorphism) with the Msp I enzyme. The relative quantification of gene expression was performed by real-time PCR. The distribution of allele and genotype frequencies did not show significant differences between the groups. The gene expression of CCR5 and SDF1 was not different between the profiles of AIDS progression. There was no significant correlation between the progression markers (CD4+ TL/CD8+ TL and VL) and the CCR5∆32 polymorphism carrier status. The 3'A allele variant was associated with a marked loss of CD4+ TLs and a higher plasma VL. Neither CCR5∆32 nor SDF1-3'A was associated with viremia control or the controlling phenotype.

Common BMI and diabetes-related genetic variants: A pilot study among indigenous people in the Brazilian Amazon.

This study was carried out to investigate the frequency of genetic variants related to body mass index (BMI) and type 2 diabetes (T2D) and evaluating the potential impact of risk alleles on susceptibility to these disorders in six indigenous peoples from Brazilian Amazon region. The majority of Fst values for pairwise population comparisons among the indigenous groups are low or moderate. The indigenous people show high values of differentiation with Africans, Europeans and Southeast Asians and moderate values with East Asian and American populations, as expected. The allelic frequencies among indigenous indicate that the majority of associations observed with T2D in continental populations can be replicated in native Amazonians. The genetic risk scores calculated for T2D in indigenous are high and similar to those calculated for Americans and East Asians, while the estimates obtained for obesity are low, probably due to the low frequencies of the risk allele of the FTO gene found in our samples. ADRB3-rs4994 and ABCC8-rs1799854 genes showed a significant association with BMI and waist circumference, and the KCNJ11-rs5219 gene with hyperglycemia. These results emphasize the importance of knowing the genetic variability underlying complex genetic diseases in indigenous peoples and the search for particular or rare variants.

High prevalence of anti-SARS-CoV-2 IgG antibody in the Xikrin of Bacajá (Kayapó) indigenous population in the brazilian Amazon.

The COVID-19 pandemic caused by Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) reached the Brazilian Amazon and spread among indigenous populations. In the present study, we demonstrate a high prevalence of infection among the Xikrin of Bacajá people (Kayapó). A sample of 100 individuals of both sexes (51 men and 49 women) with ages ranging from 2 to 82 years were clinically evaluated and tested for the presence of anti-SARS-CoV-2 IgG antibody. Among all investigated individuals, 58 were IgG-reactive (58 %) by a rapid test, and 73 (73 %) were reactive in an enzyme-linked immunosorbent assay, with no difference between sexes. Oxygen saturation ranged from 82 to 99 %, with the lowest value observed in a two-year-old girl. The results show that as expected, SARS-CoV-2 infection rapidly reached more than 70 % of the population, most likely because of the difficulties of maintaining social distance due to cultural characteristics. These results highlight the importance of indigenous health policies as a means of minimizing the impact of the pandemic on these communities.

High prevalence of human T-lymphotropic virus 2 (HTLV-2) infection in villages of the Xikrin tribe (Kayapo), Brazilian Amazon region.

BACKGROUND: Studies have shown that the human T-lymphotropic virus 2 (HTLV-2) is endemic in several indigenous populations of the Brazilian Amazon and molecular analyses have shown the exclusive presence of HTLV-2 subtype 2c among the indigenous groups of this geographical region. METHODS: The present study characterizes the prevalence of HTLV-2 infection in three new villages of the Xikrin tribe, in the Kayapo group, according to their distribution by sex and age. The study included 263 samples from individuals from the Kateté, Djujeko and Oodjã villages. Plasma samples were tested for the presence of anti-HTLV-1/2 antibodies using enzyme-linked immunosorbent assays (ELISA). Seropositive samples were confirmed using real-time PCR, nested PCR and sequencing. RESULTS: The serological and molecular results confirmed the sole presence of HTLV-2 in 77 (29%) samples, with a prevalence of 38% among women and 18% among men. In these communities, it was found that the prevalence of HTLV-2 infection increased with age. Nucleotide sequences (642 bp, 5'LTR) from eight samples were subjected to phylogenetic analysis by the neighbor-joining method to determine the viral subtype, which confirmed the presence of HTLV-2c. CONCLUSIONS: The results of the present study establish the presence of HTLV-2 infection in three new villages of the Xikrin tribe and confirm the high endemicity of the infection in the Kayapo indigenous group of the Brazilian Amazon.

Molecular genotyping of G6PD mutations and Duffy blood group in Afro-descendant communities from Brazilian Amazon.

Glucose-6-phosphate dehydrogenase deficiency (G6PDd) and Duffy-negative blood group are two red blood cells variants that confer protection against malaria. In this study, the distribution of the most common G6PD variants (G6PD*A-, GGPD*A and G6PD Mediterranean) and the major alleles of the Duffy blood group (FY*A, FY*B and FY*BES) were investigated in an Afro-descendant population from state of Pará, Brazilian Amazon. G6PD variants and Duffy blood group alleles were determined by TaqMan SNP genotyping assay. Overall, molecular genotyping revealed the presence of G6PD variants in 126 (24%) of the individuals studied (5% male and 19% female), and frequencies of the G6PD*A- and G6PD*A alleles were 0.061 and 0.104, respectively. Duffy blood group genotyping showed that 24.3% of people were Duffy-negative and 41.3% were heterozygous for FY*BES. The frequency of allele FY*BES was 41.0%. The results emphasize the need to monitor G6PD deficiency for the use of primaquine in the routine care of the Afro-descendant communities of the Trombetas, Erepecuru and Cumná rivers, evaluating the risks of hemolytic crisis in case of recurrence of malaria in the region. In addition, the possible greater protection against malaria conferred by these erythrocyte polymorphisms deserves to be better investigated and explored among these Afro-descendants.

DNA polymorphisms at BCL11A, HBS1L-MYB and Xmn1-HBG2 site loci associated with fetal hemoglobin levels in sickle cell anemia patients from Northern Brazil.

Increased levels of fetal hemoglobin (HbF, α2γ2) may reduce sickle cell anemia severity due to its ability to inhibit HbS polymerization and also reduce the mean corpuscular HbS concentration. We have investigated the influence of three known major loci on the HbF trait (HBG2, rs748214; BCL11A, rs4671393; and HBS1L-MYB, rs28384513, rs489544 and rs9399137) and HbF levels in SCA patients from the State of Pará, Northern Brazil. Our results showed that high levels of HbF were primarily influenced by alleles of BCL11A (rs4671393) and HMIP (rs4895441) loci, and to a lesser extent by rs748214 Gγ-globin (HBG2) gene promoter. The SNPs rs4671393 and rs4895441 explained 10% and 9.2%, respectively, of the variation in HbF levels, while 4.1% of trait variation was explained by rs748214. The results can be considered as in accordance with the pattern of ancestry displayed by the SCA patients: 39.6% European, 29.6% African and 30.8% Native American, and reinforce the suggestion that studies of association between genetic modifiers and clinical and laboratory manifestations in Brazil must be controlled by ancestry.

Host genetics and the profile of COVID-19 in indigenous people from the Brazilian Amazon: A pilot study with variants of the ACE1, ACE2 and TMPRSS2 genes.

This pilot study aimed to investigate genetic factors that may have contributed to the milder clinical outcomes of COVID-19 in Brazilian indigenous populations. 263 Indigenous from the Araweté, Kararaô, Parakanã, Xikrin do Bacajá, Kayapó and Munduruku peoples were analyzed, 55.2% women, ages ranging from 10 to 95 years (average 49.5 ± 20.7). Variants in genes involved in the entry of SARS-CoV-2 into the host cell (ACE1 rs1799752 I/D, ACE2 rs2285666 C/T, ACE2 rs73635825 A/G and TMPRSS2 rs123297605 C/T), were genotyped in indigenous peoples from the Brazilian Amazon, treated during the SARS-CoV-2 pandemic between 2020 and 2021. The distribution of genotypes did not show any association with the presence or absence of IgG antibodies. Additionally, the influence of genetic variations on the severity of the disease was not examined extensively because a significant number of indigenous individuals experienced the disease with either mild symptoms or no symptoms. It is worth noting that the frequencies of risk alleles were found to be lower in Indigenous populations compared to both continental populations and Brazilians. Indigenous Brazilian Amazon people exhibited an ethnic-specific genetic profile that may be associated with a milder disease, which could explain the unexpected response they demonstrated to COVID-19, being less impacted than Brazilians.

Genomic investigation on genes related to mercury metabolism in Amazonian indigenous populations.

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.

Molecular Profile of Important Genes for Radiogenomics in the Amazon Indigenous Population.

Radiotherapy is focused on the tumor but also reaches healthy tissues, causing toxicities that are possibly related to genomic factors. In this context, radiogenomics can help reduce the toxicity, increase the effectiveness of radiotherapy, and personalize treatment. It is important to consider the genomic profiles of populations not yet studied in radiogenomics, such as the indigenous Amazonian population. Thus, our objective was to analyze important genes for radiogenomics, such as ATM, TGFB1, RAD51, AREG, XRCC4, CDK1, MEG3, PRKCE, TANC1, and KDR, in indigenous people and draw a radiogenomic profile of this population. The NextSeq 500® platform was used for sequencing reactions; for differences in the allelic frequency between populations, Fisher's Exact Test was used. We identified 39 variants, 2 of which were high impact: 1 in KDR (rs41452948) and another in XRCC4 (rs1805377). We found four modifying variants not yet described in the literature in PRKCE. We did not find any variants in TANC1-an important gene for personalized medicine in radiotherapy-that were associated with toxicities in previous cohorts, configuring a protective factor for indigenous people. We identified four SNVs (rs664143, rs1801516, rs1870377, rs1800470) that were associated with toxicity in previous studies. Knowing the radiogenomic profile of indigenous people can help personalize their radiotherapy.

Molecular Profile of Variants Potentially Associated with Severe Forms of COVID-19 in Amazonian Indigenous Populations.

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.

Long-term prevalence follow-up (1967-2022) of HTLV-2 among vulnerable indigenous populations in the Amazon region of Brazil.

Introduction: Human T-lymphotropic virus 2 (HTLV-2) has been described for more than 30 years as an endemic infection in Brazilian indigenous populations, with its occurrence varying by age and sex, maintained mainly by sexual intercourse and mother-to-child transmission, favoring intrafamilial aggregation. Methods: The epidemiological scenario of HTLV-2 infection has been described among communities of the Amazon region of Brazil (ARB), with the number of retrospective positive blood samples increasing for more than 50 years. Results: Five publications were selected that showed the presence of HTLV-2 in 24 of 41 communities; the prevalence of infection was described among 5,429 individuals at five points in time. Among the Kayapó villages, the prevalence rates were described according to age and sex and reached up to 41.2%. Three communities (Asurini, Araweté, and Kaapor) were kept virus free for 27 to 38 years of surveillance. Low, medium and high prevalence levels of infection were defined, and two pockets of high endemicity were shown in the state of Pará, pointing to the Kikretum and Kubenkokrê Kayapó villages as the epicenter of HTLV-2 in the ARB. Discussion: The prevalence rates over the years have shown a decline among the Kayapó (from 37.8 to 18.4%) and an apparent change to a higher prevalence among females, but not during the first decade of life, usually associated with transmission from mother to child. Sociocultural and behavioral aspects, as well as public health policies directed toward sexually transmitted infections, might have positively influenced the decline in HTLV-2 infections.

Variants of IFNL4 Gene in Amazonian and Northern Brazilian Populations.

Since the discovery of the polymorphic nature of the IFNL4 gene, its variants have been investigated and associated with several viral diseases, with an emphasis on hepatitis C. However, the impacts of these variants on mixed-race and native populations in the northern region of Brazil are scarce. We investigated three variants of the IFNL4 gene in populations from this location, which were among the 14 most frequent variants in worldwide populations, and compared the frequencies obtained to populational data from the 1000 Genomes Project, gnomAD and ABraOM databases. Our results demonstrate that mixed-race and native populations from the northern region of Brazil present frequencies like those of European and Asian groups for the rs74597329 and rs11322783 variants, and like all populations presented for the rs4803221 variant. These data reinforce the role of world populations in shaping the genetic profile of Brazilian populations, indicate patterns of illness according to the expressed genotype, and infer an individual predisposition to certain diseases.

Molecular Profile of Variants in CDH1, TP53, PSCA, PRKAA1, and TTN Genes Related to Gastric Cancer Susceptibility in Amazonian Indigenous Populations.

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.

ß-Globin polymorphisms in Amerindian populations from the Brazilian Amazon.

OBJECTIVES: This investigation was performed to examine genetic variation at the ß-globin locus in a sample of 30 healthy individuals from native populations in South America. The patterns of haplotypic variation were compared with those of previous studies including samples for various worldwide populations in an attempt to make inferences about the occupation of the Americas from a deeper temporal perspective than is typically available with haploid markers. METHODS: A 2.67-kb segment containing the ß-globin gene and its flanking regions was examined for genetic variation in a sample of 60 chromosomes from native populations in South America. The fragment was PCR-amplified and directly sequenced. To determine linkage relationships in compound heterozygotes, we used the amplification refractory mutation system. In addition, we assessed genetic variability and differentiation among populations, and we performed tests of selective neutrality. These analyses were performed for Brazilian Amerindian group and other worldwide populations previously studied. RESULTS: Eleven polymorphic sites were found in the studied fragment, which distinguished eight different haplotypes, three recombinants haplotypes (present as single copies) and five previously described haplotypes, including some of those most highly differentiated. Genetic variation found in the pooled sample is substantial. CONCLUSIONS: Although only five known haplotypes are observed in Amazonia, some of these are highly divergent, resulting in patterns of molecular polymorphism equal to or higher than those from other world regions.

Analysis of coding variants in the human FTO gene from the gnomAD database.

Single nucleotide polymorphisms (SNPs) in the first intron of the FTO gene reported in 2007 continue to be the known variants with the greatest effect on adiposity in different human populations. Coding variants in the FTO gene, on the other hand, have been little explored, although data from complete sequencing of the exomes of various populations are available in public databases and provide an excellent opportunity to investigate potential functional variants in FTO. In this context, this study aimed to track nonsynonymous variants in the exons of the FTO gene in different population groups employing the gnomAD database and analyze the potential functional impact of these variants on the FTO protein using five publicly available pathogenicity prediction programs. The findings revealed 345 rare mutations, of which 321 are missense (93%), 19 are stop gained (5.6%) and five mutations are located in the splice region (1.4%). Of these, 134 (38.8%) were classified as pathogenic, 144 (41.7%) as benign and 67 (19.5%) as unknown. The available data, however, suggest that these variants are probably not associated with BMI and obesity, but instead, with other diseases. Functional studies are, therefore, required to identify the role of these variants in disease genesis.

Inter-individual variations in response to aerobic and resistance training in hypertensive older adults.

BACKGROUND: Hemodynamic responses to physical training are not homogenous and uniform, and considerable inter-individual variations in the blood pressure of hypertensive individuals are noted in both aerobic and resistance training protocols. In this context, this study aimed to evaluate the effects of resistance and aerobic exercise on the blood pressure responses of hypertensive older adults. METHODS: Groups were randomly divided into resistance training, n = 20; aerobic training, n = 20; control group, n = 21). After the first intervention period (12 weeks), individuals underwent a washout period (six detraining weeks), followed by a second intervention. This process is called the 'cross-over' model, where individuals who performed the aerobic exercise protocol also performed resistance training and vice-versa, constituting another 12 weeks of intervention. Blood pressure, functional performance, glycated hemoglobin and lipid profiles were evaluated preintervention and postintervention. RESULTS: Varying responses to resistance training or aerobic training stimuli were observed in the hypertensive older adult participants. Both resistance training (pre 133.2 ±â€Š14.1; post 122.4 ±â€Š7.3; P < 0.05) and aerobic training (pre 134.2 ±â€Š14.4; post 123 ±â€Š9.4; P < 0.0.5) were effective in decreasing SBP, but only aerobic training (pre 9955.3 ±â€Š1769.4; post 8800.9 ±â€Š1316.1; P < 0.05) resulted in a decreased double product, and only the resistance training group improved functional performance. CONCLUSION: Responses to resistance training or aerobic training stimuli varied noticeably between hypertensive older adults and both resistance training and aerobic training were effective in reducing SBP. This knowledge may be useful in providing individually tailored exercise prescriptions for hypertensive older adults.

Anti-SARS-CoV-2 antibodies among indigenous populations of the Brazilian Amazon: a cross-sectional study.

OBJECTIVES: The emergence of SARS-CoV-2 and its pandemic spread generated serious concern about the impact of the infection on vulnerable indigenous populations of the Brazilian Amazon. Thus, this study aimed to perform a seroepidemiological survey of anti-SARS-CoV-2 antibodies in those populations. SETTING: Six indigenous ethnic groups living in the State of Pará (Northern Brazil) were investigated. The villages of Xikrin do Bacajá, Assurini, Araweté, Parakanã, Munduruku and Kararaô were visited from October 2020 to January 2021. DESIGN AND PARTICIPANTS: We performed a cross-sectional study to investigate the prevalence of anti-spike (S1) IgG antibodies. Plasma was tested for the presence of anti-SARS-CoV-2 IgM and IgG antibodies using two assays (a lateral flow rapid test and an ELISA). A total of 1185 individuals of both sexes were enrolled in the study. RESULTS: The prevalences of IgM and IgG antibodies were 6.9% and 68.1%, respectively, ranging from 0% to 79.6%, with significant differences (p<0.001) between age groups in three communities (Araweté, Xikrin and Munduruku) and a virulence rate of 0.86%. The overall IgG prevalence obtained by rapid tests and ELISAs were similar, and the agreement of the results between the two tests was 80%, which was classified as good (kappa=0.4987; p<0.001; sensitivity of 82.1% and specificity of 71.6%). Herd immunity was probably attained, similar to that found in other communities of the Amazon. CONCLUSIONS: SARS-CoV-2 spread rapidly among the indigenous populations investigated, but it had a low mortality rate. It is necessary to expand serological investigations to other communities in the Amazon region of Brazil.

High prevalence of sexual infection by human papillomavirus and Chlamydia trachomatis in sexually-active women from a large city in the Amazon region of Brazil.

BACKGROUND: The Human Papillomavirus (HPV) and Chlamydia trachomatis are the most prevalent Sexually Transmitted Infections (STIs) worldwide, and are associated cervical cancer and pelvic inflammatory disease, respectively. However, 80% of women testing positive are asymptomatic. In the Amazon region, young women, in particular, are widely exposed to the infections and their consequences. OBJECTIVES: Determine the prevalence of sexual infection by HPV and C. trachomatis in young, sexually-active women treated at a university health program in a large city of the Brazilian Amazon region. METHODS: We amplified the L1 gene of HPV. We amplified ompA gene of C. trachomatis by nested PCR, and the study participants filled in a questionnaire on their social, epidemiological, and reproductive health characteristics. The data were analyzed using the Odds Ratio, to evaluate the degree of association of these variables with the observed infections. RESULTS: The prevalence of infection by HPV was 15.5% (47/303). This infection was recorded in 32.2% of the women of less than 25 years of age (OR:3.02 [CI95%] = 1.32-6.92; p = 0.014), 17.9% of the single women (OR: 2.41 [CI95%] = 1.22-4.75; p = 0.014), 23.8% of the women that reported having first sexual intercourse at less than 15 years of age (OR: 2.22 [CI95%] = 1.16-4.23; p = 0.021), 20% of those that reported having had more than one sexual partner during their lifetime (OR: 3.83 [CI95%] = 1.56-9.37; p = 0.003), and in 28.3% that use oral contraceptives (CI95% = 1.33-5.43; p = 0.008). The prevalence of sexual infection by C. trachomatis was 4.6% (14/303), and this bacterium was present in 16.1% of the young women of less than 25 years of age (OR: 2.86 [CI95%] = 1.33-5.43; p = 0.008). CONCLUSIONS: We found a high prevalence of HPV in young, unmarried women who started their sex lives early, who had several sexual partners in their lives and who used oral contraceptives. The prevalence of C. trachomatis was high only in young women. Our data are in accordance with other studies in Brazil and in the world and may serve to base the formulation of diagnostic and screening measures for these infections in women in the Amazon.

Characterization of DNA Polymerase Genes in Amazonian Amerindian Populations.

Due to their continuing geographic isolation, the Amerindian populations of the Brazilian Amazon present a different genetic profile when compared to other continental populations. Few studies have investigated genetic variants present in these populations, especially in the context of next-generation sequencing. Knowledge of the molecular profile of a population is one of the bases for inferences about human evolutionary history, in addition, it has the ability to assist in the validation of molecular biomarkers of susceptibility to complex and rare diseases, and in the improvement of specific precision medicine protocols applied to these populations and to populations with high Amerindian ancestry, such as Brazilians. DNA polymerases play essential roles in DNA replication, repair, recombination, or damage repair, and their influence on various clinical phenotypes has been demonstrated in the specialized literature. Thus, the aim of this study is to characterize the molecular profile of POLA1, POLE, POLG, POLQ, and REV3L genes in Amerindian populations from the Brazilian Amazon, comparing these findings with genomic data from five continental populations described in the gnomAD database, and with data from the Brazilian population described in ABraOM. We performed the whole exome sequencing (WES) of 63 Indigenous individuals. Our study described for the first time the allele frequency of 45 variants already described in the other continental populations, but never before described in the investigated Amerindian populations. Our results also describe eight unique variants of the investigated Amerindians populations, with predictions of moderate, modifier and high clinical impact. Our findings demonstrate the unique genetic profile of the Indigenous population of the Brazilian Amazon, reinforcing the need for further studies on these populations, and may contribute to the creation of public policies that optimize not only the quality of life of this population, but also of the Brazilian population.