RESUMO
The aim of the present work was to examine possible genetic risk factors related to the occurrence of cerebrovascular disease (CVD) in Brazilian population, the frequency of ß(S)-globin gene haplotypes and co-inheritance with α-thalassemia (-α(3.7kb)) and single nucleotide polymorphism of methylenetetrahydrofolate reductase (MTHFR-C677T), Factor V Leiden (FV-G1691A) and prothrombin (PT-G20210A) genes in children from Rio de Janeiro. Ninety four children with sickle cell anemia (SCA) were included, 24 patients with cerebrovascular involvement and 70 patients without CVD as control group. The mean age of children at the time of the cerebrovascular event was similar to the control group. The frequency of -α(3.7kb) thalassemia was similar in both groups (p=0.751). Children with Bantu/Atypical ß(S)-globin gene haplotype presented 15 times more chance (OR=15.4 CI 95% 2.9-81.6) of CVD than the other ß(S)-globin gene haplotypes. The C677T polymorphism of MTHFR gene was similar in both groups (p=0.085). No mutation in the FV Leiden or PT genes was found. A large study seems necessary to establish the role of these genetic polymorphisms in Brazilian miscegenated population.
Assuntos
Anemia Falciforme/genética , Transtornos Cerebrovasculares/genética , Fator V/genética , Metilenotetra-Hidrofolato Redutase (NADPH2)/genética , Polimorfismo de Nucleotídeo Único/genética , Protrombina/genética , Adolescente , Anemia Falciforme/complicações , Estudos de Casos e Controles , Criança , Pré-Escolar , Feminino , Predisposição Genética para Doença , Genótipo , Humanos , Masculino , Fatores de RiscoRESUMO
The aim of the present work was to examine possible genetic risk factors related to the occurrence of cerebrovascular disease (CVD) in Brazilian population, the frequency of βS-globin gene haplotypes and co-inheritance with α-thalassemia (-α3.7kb) and single nucleotide polymorphism of methylenetetrahydrofolate reductase (MTHFR-C677T), Factor V Leiden (FV-G1691A) and prothrombin (PT-G20210A) genes in children from Rio de Janeiro. Ninety four children with sickle cell anemia (SCA) were included, 24 patients with cerebrovascular involvement and 70 patients without CVD as control group. The mean age of children at the time of the cerebrovascular event was similar to the control group. The frequency of -α3.7kb thalassemia was similar in both groups (p=0.751). Children with Bantu/Atypical βS-globin gene haplotype presented 15 times more chance (OR=15.4 CI 95 percent 2.9-81.6) of CVD than the other βS-globin gene haplotypes. The C677T polymorphism of MTHFR gene was similar in both groups (p=0.085). No mutation in the FV Leiden or PT genes was found. A large study seems necessary to establish the role of these genetic polymorphisms in Brazilian miscegenated population.
Avaliar o papel da talassemia alfa (-α3.7kb), dos haplótipos da globina βS, e mutações nos genes da metileno-tetrahidrofolato redutase (MTHFR-C677T), fator V de Leiden (FV-G1691A) e protrombina (PT-G20210A) como fatores de risco para a doença cerebrovascular em pacientes com anemia falciforme. Foi realizado um estudo de caso controle com 94 crianças portadoras de anemia falciforme, 24 com doença cerebrovascular (DCV) e 70 sem DCV como grupo controle. A frequência de talassemia -α3.7kb foi semelhante em ambos os grupos (p=0,751). Crianças portadoras do haplótipo Bantu/Atípico da globina βS apresentam 15 vezes mais chances de desenvolverem DCV (OR=15,4 IC 95 por cento 2,9-81,6) do que os outros haplótipos. A frequência do polimorfismo MTHFR-C677T foi semelhante em ambos os grupos (p=0,085) e não foi observada mutação nos genes fator V e protrombina. Estudos com maior número de casos são necessários para esclarecer o papel desses polimorfismos genéticos na nossa população.
