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Background: Duffy blood group polymorphisms are important in areas where Plasmodium vivax predominates, because this molecule acts as a receptor for this protozoan. In the present study, Duffy blood group genotyping in P. vivax malaria patients from four different Brazilian endemic areas is reported, exploring significant associations between blood group variants and susceptibility or resistance to malaria.

We present evidence for Plasmodium vivax infection among Duffy blood group-negative inhabitants of Brazil. The P. vivax identification was determined by both genotypic and non-genotypic screening tests. The Duffy blood group was genotyped by PCR/RFLP and phenotyped using a microtyping kit. We detected two homozygous FY*B-33 carriers infected by P. vivax, whose circumsporozoite protein genotypes were VK210 and/or P. vivax-like. Additional efforts are necessary in order to clarify the evidence that P. vivax is being transmitted among Duffy blood group-negative patients from the Brazilian Amazon region.

As hemoglobinopatias são um grupo heterogêneo de distúrbios herdados recessivamente que incluem as talassemias e as doenças falciformes. As mutações que as originam são específicas de algumas regiões e em muitos casos determinadas por distribuições étnicas e geográficas, fundamentando os programas de controle destas alterações e o aconselhamento genético. O diagnóstico de alterações de hemoglobinas envolve cuidados com a metodologia aplicada e o grupo populacional que será avaliado. A informação sobre o tipo de hemoglobina alterada e o suporte clínico, psicológico e genético ao portador e seus familiares é de grande importância para o sucesso de programas preventivos nesta área. Com objetivo de avaliar as metodologias disponíveis para o diagnóstico laboratorial das hemoglobinopatias e suas aplicações em laboratórios clínicos, comparamos a incidência de hemoglobinas anormais em populações diferenciadas a saber: doadores de sangue, portadores de anemia a esclarecer, recém-nascidos, e estudantes. As metodologias aplicadas envolveram procedimentos eletroforéticos, análises citológicas e bioquímicas de triagem e para confirmação. No período de setembro de 1999 a janeiro de 2000 analisamos 524 indivíduos, com presença de formas variadas de alteração de hemoglobina para cada grupo, sendo que, dentre as amostras da população de doadores de sangue, foram diagnosticados dois casos de indivíduos heterozigotos para anemia falciforme. Rev.bras.hematol.hemoter., 2000, 22(2): [111][112][113][114][115][116][117][118][119][120][121] Palavras-chave: prevenção de hemoglobinopatias, diagnóstico laboratorial, hemoglobinas anormais, talassemias 1 -Artigo Introdução As hemoglobinopatias, também conhecidas como distúrbios hereditários da hemoglobina humana, são doenças geneticamente determinadas e apresentam morbidade significativa em todo o mundo (1). Milhões de pessoas trazem em seu patrimônio genético, hemoglobinas anormais em várias combinações com conseqüências que variam das quase imperceptíveis às letais. Dessa forma, as anemias hereditárias compreendem

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This review discusses hemoglobin D-Punjab, also known as hemoglobin D-Los Angeles, one of the most common hemoglobin variants worldwide. It is derived from a point mutation in the beta-globin gene (HBB: c.364G>C; rs33946267) prevalent in the Punjab region, Northwestern Indian. Hemoglobin D-Punjab can be inherited in heterozygosis with hemoglobin A causing no clinical or hematological alterations, or in homozygosis, the rarest form of inheritance, a condition that is commonly not related to clinical symptomatology. Moreover, this variant can exist in association with other hemoglobinopathies, such as thalassemias; the most noticeable clinical alterations occur when hemoglobin D-Punjab is associated to hemoglobin S. The clinical manifestations of this association can be similar to homozygosis for hemoglobin S. Although hemoglobin D-Punjab is a common variant globally with clinical importance especially in cases of double heterozygosis, hemoglobin S/D-Punjab is still understudied. In Brazil, for example, hemoglobin D-Punjab is the third most common hemoglobin variant. Thus, this paper summarizes information about the origin, geographic distribution, characterization and occurrence of hemoglobin D-Punjab haplotypes to try to improve our knowledge of this variant. Moreover, a list of the main techniques used in its identification is provided emphasizing the importance of complementary molecular analysis for accurate diagnosis.

Hereditary hemochromatosis is a disorder of iron metabolism characterized by increased iron intake and progressive storage and is related to mutations in the HFE gene. Interactions between thalassemia and hemochromatosis may further increase iron overload. The ethnic background of the Brazilian population is heterogeneous and studies analyzing the simultaneous presence of HFE and thalassemia-related mutations have not been carried out. The aim of this study was to evaluate the prevalence of the H63D, S65C and C282Y mutations in the HFE gene among 102 individuals with alpha-thalassemia and 168 beta-thalassemia heterozygotes and to compare them with 173 control individuals without hemoglobinopathies. The allelic frequencies found in these three groups were 0.98, 2.38, and 0.29% for the C282Y mutation, 13.72, 13.70, and 9.54% for the H63D mutation, and 0, 0.60, and 0.87% for the S65C mutation, respectively. The chi-square test for multiple independent individuals indicated a significant difference among groups for the C282Y mutation, which was shown to be significant between the beta-thalassemia heterozygote and the control group by the Fisher exact test (P value = 0.009). The higher frequency of inheritance of the C282Y mutation in the HFE gene among betathalassemic patients may contribute to worsen the clinical picture of these individuals. In view of the characteristics of the Brazilian population, the present results emphasize the need to screen for HFE mutations in beta-thalassemia carriers.