ABSTRACT
Fetal hemoglobin (HbF), encoded by the HBG2 and HBG1 genes, is the best-known genetic modulator of sickle cell anemia, varying dramatically in concentration in the blood of these patients. This variation is partially associated with polymorphisms located in the promoter region of the HBG2 and HBG1 genes. In order to explore known and unknown polymorphisms in these genes, the sequences of their promoter regions were screened in sickle cell anemia patients and correlated with both their HbF levels and their ÀS-globin haplotypes. Additionally, the sequences were compared with genes from 2 healthy groups, a reference one (N = 104) and an Afro-descendant one (N = 98), to identify polymorphisms linked to the ethnic background.The reference group was composed by healthy individuals from the general population. Four polymorphisms were identified in the promoter region of HBG2 and 8 in the promoter region of HBG1 among the studied groups. Four novel single nucleotide polymorphisms (SNP) located at positions -324, -317, -309 and -307 were identified in the reference group. A deletion located between -396 and -391 in the HBG2 promoter region and the SNP -271 C¨T in the HBG1 promoter region were associated with the Central African Republic ÀS-globin haplotype. In contrast, the -369 C¨G and 309 A¨G SNPs in the HBG2 promoter region were correlated to the Benin haplotype. The polymorphisms -396_-391 del HBG2, -369 SNP HBG2 and -271 SNP HBG1 correlated with HbF levels. Hence, we suggest an important role of HBG2 and HBG1 gene polymorphisms on the HbF synthesis.
Subject(s)
Aged , Child , Female , Humans , Male , Anemia, Sickle Cell/genetics , Polymorphism, Genetic/genetics , Promoter Regions, Genetic/genetics , gamma-Globins/genetics , Black People , Anemia, Sickle Cell/blood , Brazil , Genotype , HaplotypesABSTRACT
Amostras de carne bovina moida, de cinco acougues da cidade de Vicosa, MG, foram armazenadas a 4 graus C por 14 dias, a 0 graus C e 18 graus C por 90 dias, para analise das populacoes de bacterias nao fermentadoras de lactose (Lac-) e determinacao da sobrevivencia e da resistencia de Salmonella a drogas antimicrobianas. As amostras, submetidas ao pre-enriquecimento em caldo lactosado, apresentaram-se com populacoes de bacterias Lac-superiores as amostras sem o pre-enriquecimento. Foi observado aumento nas populacoes de celulas Lac-, nos primeiros dias de armazenamento a 4graus C e a 0graus C. Apos 21 dias,houve reducao do numero de celulas Lac- nas amostras conservadas a 0graus C. Nas amostras a 18 graus C foi observada tendencia de reducao das populacoes de celulas Lacao longo do periodo de armazenamento. Celulas de Salmonella foram isoladas de amostras em todos os tempos e temperatura.o nivel de resistencia, aos varios antibioticos, das celulas de Salmonella, foi baixo