Comparison of apolipoprotein E polymorphism and other atherosclerotic risk factors in two portuguese populations: the influence of insularity

The main objective of this study was to investigate the apolipoprotein (apo) E genotypes in Portuguese populations from mainland (Lisbon city) and from San Miguel Island, Azores' Archipelago (Ponta Delgada city) and to look for differences between these particular sites in apparently healthy subjects. Also, subjects with clinical diagnosis of atherosclerotic disease were investigated in San Miguel Island. In Lisbon, the genotypes distribution was: epsilon3/epsilon 3 > epsilon 3/epsilon 4 > epsilon 2/epsilon 3 > epsilon 4/epsilon 4 while that, for Ponta Delgada and regardless the health condition, was: epsilon 3/epsilon 3 > epsilon 2/epsilon 3 > epsilon 3/epsilon 4. Within Ponta Delgada control group, females and males had distinct genotype frequencies. The most common atherosclerotic risk factors as body mass index, blood hypertension and serum lipid parameters, presented some differences among the allelic subgroups of apo E. The major conclusions were: 1) an apparent influence of insularity in apo E polymorphism was observed; 2) both the high risk genotypes epsilon 2/epsilon 2 and epsilon 2/epsilon 4 were not found, even in patients; 3) curiously, the genotypes proportion in females was not homogenous among the three groups.

O principal objectivo deste estudo é o de pesquisar o efeito da insularidade nos polimorfismos da apolipoproteína (apo) E em indivíduos saudáveis do continente (Lisboa) e de Ponta Delgada (Ilha de S. Miguel, Arquipélago dos Açores). Adicionalmente, estudar a distribuição dos seus genótipos em doentes com aterosclerose da Ilha de S. Miguel. Em Lisboa, a distribuição dos genótipos da apo E foi a seguinte: épsilon3/épsilon3 > épsilon3/épsilon4 > épsilon2/épsilon3 > épsilon4/épsilon 4, ao passo que em Ponta Delgada e independentemente da condição fisiológica foi: épsilon 3/épsilon 3 > épsilon 2/épsilon 3 > épsilon 3/épsilon 4. Distintas frequências genotípicas foram observadas entre homens e mulheres no grupo saudável de Ponta Delgada. O índice de massa corporal, hipertensão arterial e perfil lipídico, factores de risco associados ao processo aterosclerótico, revelaram algumas diferenças quando avaliados em função dos grupos alélicos. Neste estudo, os genótipos de risco da apo E, épsilon2/épsilon2 e épsilon2/épsilon4, não foram contabilizados. Curiosamente a proporção dos genótipos nas mulheres foi heterogénea nos 3 grupos estudados.

Relevance of apolipoprotein E4 for the lipid profile of Brazilian patients with coronary artery disease

Apolipoprotein E (apoE - e2, e3, e4 alleles) plays a role in the regulation of lipid metabolism, with the e4 considered to be a risk factor for coronary artery disease (CAD). We aimed to evaluate the apoE polymorphisms in Brazilians with CAD and their influence on the lipid profile and other risk factors (hypertension, diabetes mellitus, smoking). Two hundred individuals were examined: 100 patients with atherosclerosis confirmed by coronary angiography and 100 controls. Blood samples were drawn to determine apoE polymorphisms and lipid profile. As expected, the e3 allele was prevalent in the CAD (0.87) and non-CAD groups (0.81; P = 0.099), followed by the e4 allele (0.09 and 0.14, respectively; P = 0.158). The e3/3 (76 and 78 percent) and e3/4 (16 and 23 percent) were the most common genotypes for patients and controls, respectively. The lipid profile was altered in patients compared to controls (P < 0.05), independently of the e4 allele. However, in the controls this allele was prevalent in individuals with elevated LDL-cholesterol levels only (odds ratio = 2.531; 95 percent CI = 1.028-6.232). The frequency of risk factors was higher in the CAD group (P < 0.05), but their association with the lipid profile was not demonstrable in e4 carriers. In conclusion, the e4 allele is not associated with CAD or lipid profile in patients with atherosclerosis. However, its frequency in the non-CAD group is associated with increased levels of LDL-cholesterol, suggesting an independent effect of the e4 allele on lipid profile when the low frequency of other risk factors in this group is taken into account.

Apolipoprotein E polymorphism in Brazilian dyslipidemic individuals: Ouro Preto study

The influence of apolipoprotein E alleles and genotypes on plasma lipid levels was determined in 185 individuals of mixed ethnicity living in Ouro Preto, Brazil. DNA was obtained from blood samples and the genotypes were determined by an RFLP-PCR procedure. The *3 allele was the most frequent (72 percent), followed by *4 (20 percent) and *2 (8 percent); *4 frequency was higher and *2 frequency was lower in the dyslipidemic group than in the normal control group. The *2 carriers presented lower LDL and total cholesterol levels compared to the *3 and *4 carriers. All six expected genotypes were observed in the individuals genotyped: E2/2 (2.1 percent), E4/4 (2.7 percent), E2/4 (3.7 percent), E2/3 (8.0 percent), E3/3 (53.3 percent), E3/4 (29.9 percent); no difference in genotype frequencies was found between the normal and dyslipidemic groups. Compared with *2, the presence of *3 increases more than two times the risk for dyslipidemia (OR = 2.31; P = 0.025; 95 percent CI = 1.06-5.06) and the presence of *4 increases it three times (OR = 3.31; P = 0.006; 95 percent CI = 1.36-8.04). The only significant effect of genotype was an increased risk for dyslipidemia in the *4 genotype carriers (E3/4 + E4/4) compared with the *2 genotype carriers (E2/2 + E2/3) with OR = 3.69 (95 percent CI = 1.25-10.88). The present study indicates that in the Ouro Preto admixed population the presence of APOE *2 can confer a protective effect, whereas the presence of APOE *4 implies an enhanced risk for dyslipidemia.

Association of apolipoprotein E (RFLP) polymorphism with myopia.

BACKGROUND: Myopia or nearsightedness is a spherical error of refraction, whereby the images are focused in front of retina. Eye, being an organ rich in activated oxygen species, requires a high level of antioxidants to protect the unsaturated fatty acids. Apolipoprotein E (APOE) is one of the proteins that is produced by Muller cells within the retina and is also endowed with antioxidant properties. Genetic polymorphism of APO E is controlled by three common alleles e3, e2 and e4 and rare e1, e4v at the APOE structural gene locus. Different isoforms of APO E differ in their antioxidant properties, and the e4 allele has lesser ability to combat oxidative stress. AIMS: Myopia being a disease influenced by oxidative stress, the present study was undertaken to find association of myopia with APO E polymorphism. MATERIALS AND METHODS: A total of 187 myopic cases and 192 controls were genotyped for apolipoprotein E polymorphism. RESULTS: In both controls and myopic cases, E3/3 genotype was found to be the most frequent one. There was an increase in E3/4 genotype frequency among male probands, high myopia cases and probands with early age at onset, suggesting that the E3/4 genotype might confer risk for myopia development. CONCLUSION: This association with E3/4 genotype might predispose susceptible individuals to develop high myopia and early onset myopia.

Apolipoprotein E Polymorphism in Ischemic Stroke Patients with Different Pathogenetic Origins / 대한진단검사의학회지

BACKGROUND: The association of apolipoprotein E (apoE) polymorphism with interindividual variability of serum lipid concentrations and the initiation and progression of atherosclerosis is inconclusive. This study was performed to explore the associations of apoE with lipid concentrations and ischemic stroke in patients with large artery atherosclerosis (LAA) subgroup or without atherosclerotic vascular lesions (small artery occlusion, SAO) subgroup through a case-control study among the Korean population. METHODS: The ischemic stroke group (n=194) was subdivided into an LAA subgroup (n=112) and a SAO without atherosclerotic lesion subgroup (n=82). An age-matched healthy control group (n=168) was recruited. Serum lipid concentrations were measured and apoE genotypes were determined by real-time PCR and melting curve analysis with the LightCycler (Roche Diagnostics). RESULTS: The frequency of the epsilon4 carriers was significantly higher in the ischemic stroke group (22.7%) than in the control group (11.9%) (P=0.01). However, the frequency of 4 carriers showed no difference between the LAA and SAO subgroups (22.3% vs 23.2%, P=0.89). The adjusted low density lipoprotein cholesterol (LDLc) concentration was significantly higher in ischemic stroke group than in control group (P=0.04), but showed no significant differences in all lipid concentrations between the LAA and SAO subgroups. LDLc concentrations were lower in epsilon2 carriers than in epsilon3 and epsilon4 alleles, but showed no difference between the epsilon4 carriers and epsilon3 allele. CONCLUSIONS: Although there was an association between the epsilon4 allele and ischemic stroke and between the LDLc concentration and ischemic stroke, there was no significant difference in the lipid concentrations and distribution of apoE genotypes between the LAA and SAO subgroups. Therefore, the epsilon4 allele may have different effects on the ischemic stroke that are independent of the atherosclerotic mechanism by high LDLc concentration.

Correlation Between Apolipoprotein E Gene Polymorphism and Alzheimer and Coronary Heart Disease / 中国医师杂志

Objective Apolipoprotein E(ApoE) gene polymorphism and alzheimer and coronary heart disease was studied ,and the correlation between them was evaluated.Methods The polymerase chain reaction-restriction fragment length polymorphism was used to amply 227 base-pari DNA fragment in the fourth exon of ApoE gene,and digested them with restriction enzyme CfoI,electrophoresis on 8% polyacrylamaid gel for the cleavaged products,subsequently genotype was determined by silver staining and allele frequencies were counted.Results apoE genotype and allele frequencies was detected in 33 case with Alzheimer and 37 case with coronary heart disease.The results showed that the frequencies of ApoE ? 4 was significantly higher than that in age-matched controls(P

An association analysis of apolipoprotein E genotype and Alzheimer's disease in old population in Urumqi / 临床神经病学杂志

Objective To analyse the correlation of apolipoprotein E genotype and Alzheimer's disease(AD) in old population in Urumqi.Methods The polymerase chain reaction and restriction fragment length polymorphism(PCR-RFLP) techniques were used to detect the distribution of genotype, gene frequency of ApoE alleles in 60 cases with sporadic AD and 90 normals as control.Results The frequency of ApoE?2, ApoE?3, ApoE?4 was 6.67%, 75.83% and 17.50% respectively in AD group, while in control group, it was 13.33%, 79.45% and 7.22% respectively. The frequency of ApoE?4 allele in AD group was higher than that in control group( P