Estudos dos Polimorfismos dos Genes da Apolipoproteína E (APOE) e do Receptor de LDL (RLDL - A370T) em Indivíduos Jovens Pertencentes ao Estudo do Rio de Janeiro em Seguimento de 28 Anos

Abstract

Studies have shown the association of changes in the apolipoprotein E (ApoE) and LDL receptor (LDLR) with the occurrence of cardiovascular diseases and dyslipidemia. The objective of this study was to investigate the association between different ApoE genotypes and LDLR with the persistence of changes in lipid variables in young individuals followed-up 28 years in the study of Rio de Janeiro (ERJ). Through a longitudinal study cohort, 56 subjects (35M) in A1(13.30 ± 1.53 years), A2(22.09 ± 1.91 years) and A3(31.23 ± 1.99) were investigated. On all three occasions clinical evaluation was conducted. In A2 and A3: total cholesterol, HDL, LDL and triglycerides. In A3 was added to the study of genetic polymorphisms of the ApoE and LDLR. The fragments of interest in this study were amplified by PCR (polymerase chain reaction) and the genotypes were identified by reaction with the restriction enzyme HhaI and HaeIII for ApoE and LDLR polymorphisms, respectively. ApoE genotypes were identified as ε3/ε3 (62.5%), ε3/ε4 (25%), ε2/ε3 (5.4%), ε2/ε4 (5.4%) and ε4/ε4 (1.8%) and the LDLR genotypes identified as AA (85.7%), AT (12.5%) and TT (1.8%). ε2/ε2 genotype was not observed. The analysis of the distribution of ApoE and LDLR genotypes according to the permanence of the dyslipidemia in the study sample showed that all individuals with the ApoE genotype ε2/ε4 and ε4/ε4 kept at least one lipid changes in A2 and A3 and all individuals ApoE genotype ε2/ε3 had not altered lipids in A2 and A3, while for RLDL genotype no difference was found. When analyzed individually, no lipid variable altered in A2 and/or A3, associated with these genotypes, were found. The ApoE gene polymorphism was associated with the permanence of dyslipidemia in young individuals in a longitudinal follow-up study.