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The Band 3 is a red blood cell protein that carries the DiDescribe the frequencies of the DI*A and DI*B alleles and the Band 3 Memphis among blood donors, sickle cell disease (SCD) patients and Amazonian Indians.A total of 427 blood samples were collected and separated into three groups: 206 unrelated blood donors, 90 patients with SCD and 131 Amazonian Indians. We performed DI*A/B, normal Band 3 and Band 3 Memphis genotyping, using the Polymerase Chain Reaction Restriction Fragment Length Polymorphism (PCR-RFLP).The frequency of the DI*A/DI*A genotype was 0.5% in blood donors and it was not found in other groups. The frequency of the DI*A/DI*B was higher in Amazonian Indians (33.6%) and the frequency of the DI*B/DI*B was highest in blood donors (92.2%). All 105 individuals tested were positive for the presence of normal Band 3 and of these individuals, only 5/105 (4.8%) presented the Band 3 Memphis mutation.We observed a higher frequency of the DI*B allele in blood donors and a low frequency of the DI*A/DI*A genotype in all groups studied. The Band 3 Memphis was found in a higher frequency in the blood donor group. Our findings highlight the importance of analyzing different population groups to gain a better understanding of the genetic association of blood group antigens.

Type 2 diabetes is a multifactorial disease resulting from diverse genetic and environmental factors as well as the interaction between them. Low levels of 25-hydroxyvitamin D [25(OH)D], an indicator of vitamin D status, have been associated with an increased risk of type 2 diabetes, but not consistently. Also, it remains to be determined if this association differs among ethnic groups. Therefore, we aimed to evaluate vitamin D status and its association with glucose intolerance in a Brazilian indigenous population, the Xavante Indians.The study population consisted of 819 full Xavante Indians (410 women), aged ≥18 years and living in two indigenous reserves located in Mato Grosso State, central region of Brazil. Clinical examination and anthropometrical measurements were made, blood samples were obtained for total cholesterol, HDL-cholesterol, triglycerides and 25(OH)D measurement. Fasting and 2-h post 75 g oral glucose load capillary glucose was measured. Vitamin D status was defined by serum 25(OH)D levels: vitamin D sufficiency (25(OH)D: 30-100 ng/mL), vitamin D insufficiency (25(OH)D: 20-30 ng/mL) and vitamin D deficiency (25(OH)D:20 ng/mL). Multiple logistic regression was performed to identify independent associations between 25(OH)D levels and impaired glucose tolerance or diabetes mellitus.Analyses stratified by 25(OH)D levels shows that 65.5% of the population had vitamin D deficiency/insufficiency (25(OH)D 30 ng/mL). 25(OH)D concentrations were lower in individuals with impaired glucose tolerance or diabetes mellitus than in normal glucose tolerant individuals. Multiple logistic regression analysis showed an inverse association between increments of 25(OH)D and presence of diabetes mellitus (OR per 1 ng/mL increase in 25(OH)D: 0.97; 95% confidence interval: 0.95-0.99), or impaired glucose tolerance (OR per 1 ng/mL increase in 25(OH)D: 0.87; 95% confidence interval: 0.85-0.89), in an age, sex, BMI and season of sampling-adjusted model.The present population-based study found a high prevalence of hypovitaminosis D among Xavante Indians. In this at-risk population of type 2 diabetes, a significant association of higher serum 25(OH)D with a decreased prevalence of diabetes mellitus and impaired glucose tolerance was observed.

Aims To evaluate the feasibility of smartphone based retinal photography for diabetic retinopathy (DR) screening among Brazilian Xavante Indians and the yield of retinal images. Methods A non-probabilistic cluster sample of 170 individuals with and without diabetes was enrolled for ocular examination with a portable retinal camera during DR screening at two Xavante Reservations. Due to operational conditions and to optimize the field work, only the larger Xavante villages were included. Images were obtained after pupil dilation; image analysis included assessment of quality, presence of media opacities and diabetic retinopathy grading whenever possible for individuals with diabetes. Results A total of 157 individuals underwent the complete ocular imaging protocol, 95 with diabetes (60.5%). Among those with diabetes, 23 (24.2%) could not have DR graded because of media opacities. For those with gradable images, the frequency of DR was 22.2%; sight-threatening DR was present in 9.7%. The main causes for ungradable images were cataracts and asteroid hyalosis. Conclusions The presence of DR was higher than in previous studies, calling attention for its prevention in this vulnerable population. The screening model with a smartphone-based portable retinal camera is feasible and could increase screening coverage if associated with telemedicine.

The aim of this study was to evaluate the usefulness of Body Adiposity Index (BAI) as a predictor of body fat in Xavante Indians and to investigate which anthropometric measures of adiposity best correlate with body fat in this population.We evaluated 974 individuals (476 male), aged 42.3 ± 19.5 years. Percentage of body fat (%BF) determined by bioimpedance analysis (BIA) was used as the reference measure of adiposity. Bland-Altman analysis was used to assess the agreement between the two methods: BAI and BIA. Associations between anthropometric measures of adiposity were investigated by Pearson correlation analysis.BAI overestimates %BF (mean difference: 4.10%), mainly at lower levels of adiposity. Significant correlations were found between %BF and all measurements, being the strongest correlation with BAI. However, stratified analyses according to gender showed that among men waist circumference has the strongest correlation (r = 0.73, p0.001) and among women BAI (r = 0.71, p0.001), BMI (r = 0.69, p0.001) and waist circumference (r = 0.70, p0.001) performed similarly.BAI can be a useful tool to predict %BF in Xavante Indians, although it has some limitations. However, it is not a better predictor of adiposity than waist circumference in men or BMI and waist circumference in women.

Paracoccidioidomicose é considerada a micose sistêmica endêmica mais prevalente na América Latina. Apesar da maior parte da casuística de paracoccidioidomicose ocorrer entre trabalhadores rurais, há poucos casos documentados de ocorrência dessa micose entre índios brasileiros. São apresentados 2 casos de paracoccidioidomicose em índios Suruí, família linguística Tupi-Mondé, procedentes de Cacoal, Rondônia. Ambos apresentaram sorologia positiva à imunodifusão apenas com antígenos da fase miceliana do P. brasiliensis. Os autores apresentam revisão de literatura sobre a ocorrência dessa micose entre índios brasileiros e discutem a necessidade de futuras investigações buscando caracterizar as diferenças regionais de cepas de P. brasiliensis e seu impacto no diagnóstico sorológico dessa micose. Paracoccidioidomycosis has been considered the most frequent endemic systemic mycosis in Latin America. Although most cases of paracoccidioidomycosis involve rural workers, this systemic fungal disease has been scarcely reported among Amerindian populations from Brazil. We report two cases of paracoccidioidomycosis in Tupi-Mondé Amerindians from Cacoal, state of Rondônia, Brazil. Both cases exhibited positive serological results by a specific immunodiffusion test only when the assay was performed with antigens obtained from the mycelial form of P. brasiliensis. The authors present a literature review of paracoccidioidomycosis in Brazilian Amerindians and discuss the need for further investigations about the impact of the antigenic diversity of P. brasiliensis from different geographic areas on the serological diagnosis of PCM. Universidade Federal de São Paulo (UNIFESP) UNIFESP SciELO

HNA-3 antigens are the result of a rs2288904 single-nucleotide polymorphism (SNP) in the CTL2, and the HNA-3a and HNA-3b variants are encoded by a guanine and adenine at Nucleotide Position 461. Anti-HNA-3 are involved in severe transfusion-related acute lung injury reactions and in neonatal alloimmune neutropenia. Since the distribution of the HNA-3 system was unknown in South Americans, in this study we determined the frequency of the HNA-3 alleles in Brazilians.DNA of 500 blood donors, 120 Xikrin Amerindians, 74 Japanese individuals, and 124 African Brazilians were genotyped for rs2288904 by a polymerase chain reaction (PCR)-restriction fragment length polymorphism assay. The PCR product was digested with enzyme Taq(α) 1, specific to nucleotide guanine (HNA-3a).The results showed that the frequencies of the HNA-3a/HNA-3b alleles were 0.81/0.19 in blood donors, 1.00/0.00 in Amerindians, 0.63/0.37 in Japanese, and 0.85/0.15 in African Brazilians. All 81 individuals genotyped as HNA-3a/a did not present the SNP c.457T by molecular sequencing.The frequencies of HNA-3 genotypes in Brazilian blood donors is similar to that described in Caucasians; however, all Amerindians were HNA-3a/a, African Brazilians showed a lower frequency of HNA-3b/b, and Japanese had a higher prevalence of HNA-3b/b, suggesting that they may be at risk for developing anti-HNA-3a alloantibodies.

Characterization of population genetic variation and structure can be used as tools for research in human genetics and population isolates are of great interest. The aim of the present study was to characterize the genetic structure of Xavante Indians and compare it with other populations. The Xavante, an indigenous population living in Brazilian Central Plateau, is one of the largest native groups in Brazil. A subset of 53 unrelated subjects was selected from the initial sample of 300 Xavante Indians. Using 86,197 markers, Xavante were compared with all populations of HapMap Phase III and HGDP-CEPH projects and with a Southeast Brazilian population sample to establish its population structure. Principal Components Analysis showed that the Xavante Indians are concentrated in the Amerindian axis near other populations of known Amerindian ancestry such as Karitiana, Pima, Surui and Maya and a low degree of genetic admixture was observed. This is consistent with the historical records of bottlenecks experience and cultural isolation. By calculating pair-wise F(st) statistics we characterized the genetic differentiation between Xavante Indians and representative populations of the HapMap and from HGDP-CEPH project. We found that the genetic differentiation between Xavante Indians and populations of Ameridian, Asian, European, and African ancestry increased progressively. Our results indicate that the Xavante is a population that remained genetically isolated over the past decades and can offer advantages for genome-wide mapping studies of inherited disorders.

CONTEXT: Latent autoimmune diabetes of the adult (LADA) as originally described represents perhaps as many as 10 -- 20% of adult-onset patients with diabetes. DESIGN: case report. CASE REPORT: A 38-year-old Brazilian Xavante-Jê Indian with Latent Autoimmune Diabetes of the Adult (LADA) is described, coming from the Sangradouro community in Poxoréu, Mato Grosso. The onset of diabetes after reaching 25 years of age, the evolution to insulin deficiency after a period of insulin-independence and the presence of auto-antibodies to glutamic acid decarboxylase (GAD) characteristic of LADA were present. This patient may represent the first case of LADA in a Brazilian with full Indian heritage. Further studies are necessary to verify the prevalence of this new type of diabetes in this population that does not have Caucasoid admixture and has a particular environmental background.