Identificação e caracterização do traço talassêmico beta em anêmicos de Porto Alegre, RS

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The effects of old and recent migration waves in the distribution of HBB*S globin gene haplotypes

Sickle cell hemoglobin is the result of a mutation at the sixth amino acid position of the beta () globin chain. The HBB*S gene is in linkage disequilibrium with five main haplotypes in the -globin-like gene cluster named according to their ethnic and geographic origins: Bantu (CAR), Benin (BEN), Senegal (SEN), Cameroon (CAM) and Arabian-Indian (ARAB). These haplotypes demonstrated that the sickle cell mutation arose independently at least five times in human history. The distribution of S haplotypes among Brazilian populations showed a predominance of the CAR haplotype. American populations were clustered in two groups defined by CAR or BEN haplotype frequencies. This scenario is compatible with historical records about the slave trade in the Americas. When all world populations where the sickle cell gene occurs were analyzed, three clusters were disclosed based on CAR, BEN or ARAB haplotype predominance. These patterns may change in the next decades due to recent migrations waves. Since these haplotypes show different clinical characteristics, these recent migrations events raise the necessity to develop optimized public health programs for sickle cell disease screening and management

Influence of CYP19A1 polymorphisms on the treatment of breast cancer with aromatase inhibitors : a systematic review and meta-analysis

Background: Many clinical trials have shown the efficacy of aromatase inhibitors (AIs) in the management of breast cancer (BC). There is growing evidence that CYP19A1 single-nucleotide polymorphisms (SNPs) are associated with clinical response (CR) and adverse effects (AEs) among BC patients treated with AIs. The aim of this study was to analyze the association between CYP19A1 polymorphisms and AI treatment in BC patients. Methods: A systematic review was performed in MEDLINE, EMBASE, and LILACS. A meta-analysis was conducted to compare the association between CYP19A1 variants and treatment response among BC patients. Results: A total of 12 studies were included in the final analysis. There was significant variation among the populations studied and the SNPs and outcomes investigated. A meta-analysis was only possible for the evaluation of SNP rs4646 vs. the wild-type variant with respect to time to progression (TTP) among metastatic BC patients treated with AI. TTP was significantly increased in patients with the rs4646 variant compared with the wild-type gene (hazard ratio (HR) = 0.51 [95 % confidence interval (CI), 0.33–0.78], P = 0.002). Seven studies analyzed the association between AEs with different polymorphisms of CYP19A1. Although there was a statistically significant association with musculoskeletal adverse events (rs934635, rs60271534, rs700518rs, and haplotype M_3_5) and with vasomotor symptoms (rs934635, rs1694189, rs7176005, and haplotype M_5_3) in individual studies, similar associations were not observed in further studies. No statistically significant association between musculoskeletal AEs and SNPs rs4646, rs10046, rs727479, and rs1062033 was found. Conclusions: These findings suggest that the presence of the rs4646 variant may be a predictive factor of the benefit of AI treatment for BC. The effects of CYP19A1 polymorphisms on clinical outcomes were most often detected in individual studies, suggesting that longer-term studies will better clarify these associations. Additional studies are needed to clarify the predictive value of other SNPs and whether CYP19A1 genotyping should be used to guide AI treatment

Estratificação populacional em sul-americanos de origem européia e sua importância para a pesquisa genética psiquiátrica no Brasil

Universidade de São Paulo Medical School Department and Institute of PsychiatryUniversidade Federal de Minas Gerais Medical School Department of Mental HealthUniversidade Federal de São Paulo (UNIFESP) Department of Psychiatry Interdisciplinary Laboratory of Clinical NeuroscienceUniversidade Federal do Rio Grande do Sul Department of GeneticsUNIFESP, Department of Psychiatry Interdisciplinary Laboratory of Clinical NeuroscienceSciEL

Uma revisão sobre a pesquisa genética psiquiátrica na população brasileira

OBJECTIVE AND METHOD: A large increase in the number of Brazilian studies on psychiatric genetics has been observed in the 1970's since the first publications conducted by a group of researchers in Brazil. Here we reviewed the literature and evaluated the advantages and difficulties of psychiatric genetic studies in the Brazilian population. CONCLUSION: The Brazilian population is one of the most heterogeneous populations in the world, formed mainly by the admixture between European, African and Native American populations. Although the admixture process is not a particularity of the Brazilian population, much of the history and social development in Brazil underlies the ethnic melting pot we observe nowadays. Such ethnical heterogeneity of the Brazilian population obviously brings some problems when performing genetic studies. However, the Brazilian population offers a number of particular characteristics that are of major interest when genetic studies are carried out, such as the presence of isolated populations. Thus, differences in the genetic profile and in the exposure to environmental risks may result in different interactions and pathways to psychopathology.OBJETIVO E MÉTODO: Desde a década de 70, quando os primeiros estudos em genética psiquiátrica conduzidos por um grupo de brasileiros foram publicados, o número de trabalhos realizados no Brasil vem aumentando consideravelmente. Através desta revisão, avaliamos as vantagens e as dificuldades da realização de pesquisas em psiquiatria genética na população brasileira. CONCLUSÃO: A população brasileira é uma das mais heterogêneas do mundo, formada principalmente pela combinação entre populações européia, africana e nativa americana. Apesar de a mistura entre raças não ser uma particularidade da população brasileira, a história e o desenvolvimento social no Brasil ocasionou uma grande miscigenação étnica, a qual é observada atualmente. Devido à heterogeneidade de suas origens, diversos problemas são levantados em estudos genéticos realizados no Brasil. Porém, a população brasileira oferece características particulares para desenvolvimento de pesquisas genéticas, como a presença de populações isoladas. Portanto, diferenças genéticas e exposição a riscos ambientais podem resultar em diferentes interações e caminhos para alterações psicopatológicas