Associations of LPL and APOC3 gene polymorphisms on plasma lipids in a Mediterranean population: interaction with tobacco smoking and the APOE locus

We conducted a cross-sectional study in a Spanish population (n = 1,029) to investigate associations between the LPL and APOC3 gene loci (LPL-HindIII, LPL-S447X, and APOC3-SstI) and plasma lipid levels and their interaction with APOE polymorphisms and smoking. Carriers of the H(-) or the X447 allele had higher levels of HDL cholesterol (HDL-C), and lower levels of TG, after adjustment for age, body mass index, alcohol, smoking, exercise, and education (P < 0.01). The APOC3 polymorphism presented additive effects to the LPL variants on TG and HDL-C levels in men, and on TG in women. The most and the least favorable haplotype combinations were H(-)/X447/S1 and H(+)/S447/S2, respectively. These combinations accounted for 7% and 5% of the variation in HDL-C and TG in men, and 3% and 4% in women. There was a significant interaction between APOE and LPL variants and HDL-C levels in both genders (P < 0.05). The increases in HDL-C observed for the rare alleles were higher in epsilon4 than in epsilon3 subjects, and absent in epsilon2 individuals. This effect was modulated by smoking (interaction HindIII-APOE-smoking, P = 0.019), indicating that smoking abolished the increase in HDL-C levels observed in epsilon4/H(-) subjects.Understanding this gene-gene-environmental interaction may facilitate preventive interventions to reduce coronary artery disease risk.     

Association of lipoprotein lipase and apolipoprotein C-III genes polymorphism with acute myocardial infarction in diabetic patients

Lipoprotein lipase (LPL) and Apolipoprotein C-III (APOC-III) play an important role in lipid metabolism. The aim of this study was to explore the possible associations of the gene polymorphisms (LPL HindIII, LPL Ser(447)-Ter and APOC3 SstI), diabetes mellitus, and plasma lipids with myocardial infarction. The polymorphisms were assessed by restriction assay in 200 Egyptian MI patients (100 diabetic and 100 non-diabetic) and 100 healthy controls. This study demonstrated that individuals with the H2H2 genotype or S2 allele have more than three times higher relative risk of suffering from MI than those carrying the H1H1 or S1S1. Type 2 DM mainly lowers HDL-C levels in MI patients who carry H2H2 or S2S2 genotype and increases TC, TG, and LDL levels in MI patients carrying H2H2 or S2S2 genotype compared with non-diabetic MI patients carrying the same genotypes. In S447X polymorphism, it was observed that DM led to loss of the protective lipid profile in MI patients carrying 447XX genotype. These findings suggest that H2H2 or S2S2 genotypes are associated with dyslipidemia and increased risk of myocardial infarction. The S447X polymorphism is associated with a favorable lipid profile. However, the association of diabetes mellitus with these polymorphisms leads to unfavorable lipid profile.     

Polymorphisms in the gene encoding lipoprotein lipase in men with low HDL-C and coronary heart disease: the Veterans Affairs HDL Intervention Trial

Our goal was to further define the role of LPL gene polymorphisms in coronary heart disease (CHD) risk. We determined the frequencies of three LPL polymorphisms (D9N, N291S, and S447X) in 899 men from the Veterans Affairs HDL Intervention Trial (VA-HIT), a study that examined the potential benefits of increasing HDL with gemfibrozil in men with established CHD and low high density lipoprotein cholesterol (HDL-C; < or =40 mg/dl), and compared them with those of men without CHD from the Framingham Offspring Study (FOS). In VA-HIT, genotype frequencies for LPL D9N, N291S, and S447X were 5.3, 4.5, and 13.0%, respectively. These values differed from those for men in FOS having an HDL-C of >40, who had corresponding values of 3.2% (P = 0.06), 1.5% (P < 0.01), and 18.2% (P < 0.01). On gemfibrozil, carriers of the LPL N9 allele in VA-HIT had lower levels of large LDL (-32%; P < 0.01) but higher levels of small, dense LDL (+59%; P < 0.003) than did noncarriers. Consequently, mean LDL particle diameter was smaller in LPL N9 carriers than in noncarriers (20.14 +/- 0.87 vs. 20.63 +/- 0.80 nm; P < 0.003). In men with low HDL-C and CHD: 1) the LPL N9 and S291 alleles are more frequent than in CHD-free men with normal HDL-C, whereas the X447 allele is less frequent, and 2) the LPL N9 allele is associated with the LDL subclass response to gemfibrozil.     

Polymorphic gene markers of lipid metabolism are associated with diabetic nephropathy in patients with type 1 diabetes mellitus

In groups of type 1 diabetes mellitus patients with and without clinical signs of diabetic nephropathy (n = 62 and n = 68, respectively), a search was made for associations between diabetic nephropathy and the polymorphic marker epsilon2/epsilon3/epsilon4 of apolipoprotein E gene (APOE), I/D marker of apolipoprotein B gene (APOB), and Ser447Ter marker of lipoprotein lipase-encoding gene (LPL). The risk of diabetic nephropathy was higher in the carriers of allele epsilon3 and genotype epsilon3/epsilon3 of the polymorphic marker epsilon2/epsilon3/epsilon4 of APOE gene as well as in the carriers of allele 1 and APOB genotype/gene (OR = 2.08 and 2.16; 1.91 and 2.11, respectively). Conversely, the carriers of allele D showed a reduced risk of this complication (OR = 0.52). No significant differences in distribution of alleles and genotypes of the polymorphic marker Ser447Ter of LPL gene were found between the groups. Our results indicate that the genes encoding two major components of lipid metabolism are involved in the development of diabetic nephropathy in patients with type 1 diabetes mellitus.     

Cigarette smoking, blood pressure and serum lipids and lipoproteins in middle-aged women

The relationship of cigarette smoking with blood pressure and serum lipids and lipoproteins was studied in the 3934 middle-aged women aged 40 to 59 years. After adjusting age, body mass index (BMI), alcohol intake and physical activity scores, the mean systolic and diastolic blood pressures (SBP and DEP, respectively) did not indicate dose-dependent relationships. The largest significant mean differences in SBP (4.6 mmHg), DBP (3.9 mmHg), high density lipoprotein cholesterol (HDL-C) (9.6 mg/dL), ratio of total cholesterol to HDL-C (TC/HDL-C) (0.8), triglycerides (TG) (22.9 mg/dL) and the logarithmic transformation of TG (Log TG) (0.26) were found between the non-smokers and smokers. When age, BMI, alcohol intake and physical activity scores were included in the forward stepwise multiple regression analyses, there were negative relationships found for cigarette smoking and SBP, DBP and HDL-C and positive relationships for cigarette smoking and TC/HDL-C, TG, Log TG and low density lipoprotein cholesterol. Although the results are somewhat variable, the present study shows cigarette smoking is negatively associated with SBP and DBP and unfavorably associated with serum lipids and lipoproteins in middle-aged women.     

Gene polymorphisms in the Quebec population: a risk to develop hypertriglyceridemia

In Eastern Québec, two major lipoprotein lipase (LPL) gene mutations, P207L and G188E, lead to complete LPL deficiency in homozygote subjects and contribute to elevated predisposition to hypertriglyceridemia in heterozygotes. First, we determined the allele frequencies of LPL (D9N, G188E, P207L, D250N, N291S, and S447X), APOE (C112R and C158R), PPARalpha (L162V), and PPARgamma2 (P12A) single nucleotide polymorphisms (SNPs) in a random-based cohort of the metropolitan Québec city area. Second, we compared the LPL X447 allele frequencies observed in the random cohort and in a cohort of LPL P207L deficient patients. In the random cohort, the LPL N9 rare allele exhibited a higher prevalence than previously expected (p=0.0001). The LPL X447 allele frequency was lower in the patient cohort (Freq: 4.4%) than in the random cohort (Freq: 11.2%) (p=0.0001). These results reveal the importance of genetic screening for LPL gene mutations D9N and S447X in a population at risk to develop hypertriglyceridemia.     

Lipoprotein lipase and apoE polymorphisms: relationship to hypertriglyceridemia during pregnancy.

Pregnancy is associated with increases in plasma total cholesterol (TC) and triglycerides (TG). Individuals with decreased LPL activity have a mild form of hypertriglyceridemia. Variations in the apolipoprotein E (apoE) gene have been associated with increases in plasma TG in addition to differences in plasma TC, LDL cholesterol (LDL-C), and HDL cholesterol (HDL-C). Because of the overproduction of TG-rich VLDL, normal pregnancy challenges the lipolytic capacity of LPL and the clearance of remnants particles. During pregnancy, LPL and apoE polymorphisms may contribute to hypertriglyceridemia. This study investigated the impact of three LPL polymorphisms and the apoE genotypes on lipid levels during pregnancy. Fasting plasma lipids were measured and analyses of the LPL and apoE polymorphisms were performed in 250 women in the third trimester of pregnancy. S447X carriers had lower TG (P = 0.003), and N291S carriers had lower HDL-C (P < 0.02) and higher fractional esterification rate of HDL (FER(HDL)) (P = 0.007), a measure of HDL particle size, than the noncarriers. The E2 allele was associated with lower TC, LDL-C, and FER(HDL) (P < 0.05) compared to the E3/E3 genotype. These findings support that LPL and apoE polymorphisms play an important role in lipid metabolism in pregnancy. The relationship of these polymorphisms to risk of coronary heart disease in women requires further study.     

Evidence of LPL gene-exercise interaction for body fat and LPL activity: the HERITAGE Family Study.

Evidence of a gene-exercise interaction for traits related to body composition is limited. Here, the association between the lipoprotein lipase (LPL) S447X polymorphism and changes in body mass index, fat mass, percent body fat, abdominal visceral fat measured by computed tomography, and post-heparin plasma LPL activity in response to 20 wk of endurance training was investigated in 741 adult white and black subjects. Changes were compared between carriers and noncarriers of the X447 allele after adjustment for the effects of age and pretraining values. No evidence of association was observed in men. However, white women carrying the X447 allele exhibited greater reductions of body mass index (P = 0.01), fat mass (P = 0.01), and percent body fat (P = 0.03); in black women, the carriers exhibited a greater reduction of abdominal visceral fat (P = 0.05) and a greater increase in post-heparin LPL activity (P = 0.02). These results suggest that the LPL S447X polymorphism influences the training-induced changes in body fat and post-heparin LPL activity in women but not in men.     

Subsets of SNPs define rare genotype classes that predict ischemic heart disease

Single nucleotide polymorphisms (SNPs) are hypothesized to explain the genetic predisposition to ischemic heart disease (IHD) in the general population. Lack of evidence for a role of such variation is fostering pessimism about the utility of genetic information in the practice of medicine. In this study we determined the utility of exonic and 5' SNPs in apolipoprotein E (APOE) and lipoprotein lipase (LPL) when considered singly and in combination for predicting incidence of IHD in 8,456 individuals from the general population during 24 years of follow-up. In men, LPL D9N improved prediction of IHD (P = 0.03) beyond smoking, diabetes and hypertension. The group of men heterozygous and homozygous for the rare D9N variant had a hazard ratio (HR) of 1.69 (95% confidence interval = 1.10-2.58) relative to the most common genotype. Pairwise combinations of D9N with -219G > T in APOE and N291S and S447X in LPL significantly improved the prediction of IHD (P = 0.05 in women, P = 0.04 in men, P = 0.03 in men, respectively) beyond smoking, diabetes and hypertension, and identified subgroups of individuals (n = 6-94) with highly significant HRs of 1.92-4.35. These results were validated in a case-control study (n = 8,806). In conclusion, we present evidence that combinations of SNPs in APOE and LPL identify subgroups of individuals at substantially increased risk of IHD beyond that associated with smoking, diabetes and hypertension.     

Lipoprotein metabolism of pregnant women is associated with both their genetic polymorphisms and those of their newborn children

To explore whether the placenta contributes to the lipoprotein metabolism of pregnant women, we took advantage of the fact that placental proteins are encoded from the fetal genome and examined the associations between lipids of 525 pregnant women and the presence, in their newborns, of genetic polymorphisms of LPL and apolipoprotein E (APOE), two genes expressed in placenta. After adjustment for maternal polymorphisms, newborn LPL*S447X was associated with lower triglycerides (-21 +/- 9 mg/dl), lower LDL-cholesterol (LDL-C; -12 +/- 5 mg/dl), lower apoB (-14 +/- 4 mg/dl), higher HDL-C (5 +/- 2 mg/dl), and higher apoA-I (9 +/- 4 mg/dl) in their mothers; newborn LPL*N291S was associated with higher maternal triglycerides (114 +/- 31 mg/dl); and newborn APOE*E2 (compared to E3E3) was associated with higher maternal LDL-C (14 +/- 6 mg/dl) and higher maternal apoB (14 +/- 5 mg/dl). These associations (all P < 0.05) were independent of polymorphisms carried by the mothers and of lipid concentrations in newborns and were similar in amplitude to the associations between maternal polymorphisms and maternal lipids. Such findings support the active role of placental LPL and APOE in the metabolism of maternal lipoproteins and suggest that fetal genes may modulate the risk for problems related to maternal dyslipidemia (preeclampsia, pancreatitis, and future cardiovascular disease).     

Sex-specific interaction between APOE genotype and carbohydrate intake affects plasma HDL-C levels: the Strong Heart Family Study

Low plasma levels of high-density lipoprotein cholesterol (HDL-C) are identified as a risk factor for cardiovascular disease (CVD). Sexual dimorphism, however, is widely reported in both HDL-C and CVD, with the underlying explanations of these sexual differences not fully understood. HDL-C is a complex trait influenced by both genes and dietary factors. Here we examine evidence for a sex-specific effect of APOE and the macronutrient carbohydrate on HDL-C, triglycerides (TG) and apoprotein A-1 (ApoA-1) in a sample of 326 male and 423 female participants of the Strong Heart Family Study (SHFS). Using general estimating equations in SAS to account for kinship correlations, stratifying by sex, and adjusting for age, body mass index (BMI) and SHS center, we examine the relationship between APOE genotype and carbohydrate intake on circulating levels of HDL-C, TG, and ApoA-1 through a series of carbohydrate-by-sex interactions and stratified analyses. APOE-by-carbohydrate intake shows significant sex-specific effects. All males had similar decreases in HDL-C levels associated with increased carbohydrate intake. However, only those females with APOE-4 alleles showed significantly lower HDL-C levels as their percent of carbohydrate intake increased, while no association was noted between carbohydrate intake and HDL-C in those females without an APOE-4 allele. These findings demonstrate the importance of understanding sex differences in gene-by-nutrient interaction when examining the complex architecture of HDL-C variation.     

Apolipoprotein E and H polymorphisms in Mongolian Buryat: allele frequencies and relationship with plasma lipid levels

A Buryat population consisting of seven tribal groups in eastern Mongolia has been screened to determine the frequency distribution of different apolipoprotein E and H alleles (APOE and APOH, genes) coding for common isoforms and their association with quantitative plasma lipid levels. Allele frequencies at the APOE locus in 125 healthy Buryat aged 17 to 73 years were highest for APOE*3 (0.804), followed by APOE*4 (0.164) and APOE*2 (0.032). The APOH locus had high frequencies of APOH*2 (0.912) and APOH*3 (0.088). APOH*1 was not detected. No significant differences were observed in the overall APOE allele frequencies between the Buryat and the Siberian Evenki, Inuits, and Indians in Asia, or with some European whites. The frequency distribution of the overall APOH alleles of the Buryat was similar to that of the Japanese in Asia. Overall plasma lipid levels of the Buryat (males aged 20 to 73 years, females aged 21 to 64 years) were considerably lower, comparable to those of the Evenki. The APOE*4/E*3 males had significantly high total- and LDL-cholesterol levels compared with the APOE*3/E*3 males (p < 0.025 and p < 0.01, respectively). No significant effects of the APOH genotypes on any of the plasma lipid levels were observed. In particular, our data regarding APOE suggest that the Buryat are genetically close in allele frequencies to the Evenki and Inuits, but differ from them in the association of genotype APOE*4/E*3 with cholesterol levels.     

The effect of fat intake and antihypertensive drug therapy on serum lipid profile: a cross-sectional survey of serum lipids in male and female hypertensives

The present study aimed to investigate the effect of betablocker with diuretics therapy on serum cholesterol and high density lipoprotein (HDL-C) lipids in cross-sectional data (age, sex, weight, and body mass index (BMI), smoking/alcoholic consumption) and supplemented vegetarian low-fat diet with daily low fat energy intake, salt intake, duration of drug therapy, and serum protein as effective measures of lowering blood pressure among hypertensives in both males and females. Hypertensive patients on betablocker and/or thiazide therapy were compared in cross-section study with their age, blood pressure, fat intake, serum lipid profile, BMI, and serum albumin in males and females. Dietary fat intake and serum lipid profile were income related. Betablocker and diuretics therapy in combination with dietary fat intervention was beneficial for prolonged dyslipidemia control. Serum cholesterol level was main contributing factor dependent on BMI, duration of drug, and socio-economic factors. Fat intake contributed in hypertension and serum cholesterol levels. A cross-sectional data analysis showed beneficial effects of “low fat-salt-smoking-alcohol consumption and combined polyunsaturated fatty acid with antihypertensive therapy approach” to keep normal dyslipidemia and hypertension. Low fat intake, low salt, smoking, alcohol consumption, and combination of dietary oil supplements with lipid betablockers and diuretic modulators were associated with low hypertension and controlled dyslipidemia in Asian sedentary population.     

Association of two genetic variations of lipoprotein lipase, S447X and Hind III, with coronary artery disease and hypertriglyceridemia

This study was performed to assess the effect of the S447X and Hind III lipoprotein lipase gene polymorphisms on development of coronary artery disease and hypertriglyceridemia. The study included 132 patients and 98 healthy control subjects of Croatian descent. The lipoprotein lipase S447X polymorphism was associated with coronary artery disease and hypertriglyceridemia, as indicated by the lower frequency of S447 allele in the patient group (p = 0.005) and odds ratio (O.R = 0.40, p = 0.006). The patient and control groups also showed a significant difference in the distribution of Hind III/S447X genotype combinations (p = 0.013). There were no significant associations with lipid parameters for any genotype or genotype combination in the patient group. Frequencies of the S447X polymorphism and S447X/Hind III combinations differed between the CAD/TG and control group, thus these polymorphisms may be associated with CAD and hypertriglyceridemia.     

Relations of APOE promoter polymorphisms to LDL cholesterol and markers of subclinical atherosclerosis in young adults

The common apolipoprotein E (apoE) gene (APOE) epsilon2/epsilon3/epsilon4 polymorphism explains part of serum lipid variation, and polymorphisms in the APOE promoter region have been proposed to participate in the regulation of serum lipid levels within the most common APOE epsilon3/epsilon3 genotype group. We determined APOE -219G/T and +113G/C promoter genotypes and estimated APOE haplotypes in 525 participants of the Cardiovascular Risk in Young Finns Study. We studied the associations of the APOE promoter polymorphisms and their haplotypes with cross-sectional and longitudinal serum lipid and apolipoprotein concentrations as well as with flow-mediated dilatation (FMD), carotid artery compliance (CAC), and intima-media thickness (IMT) within the APOE epsilon3/epsilon3 carriers. We found no significant association between the APOE promoter genotypes and serum lipids [low density lipoprotein-cholesterol (LDL-C), HDL-C, and triglycerides], apolipoproteins (apoA-I and apoB), or brachial artery FMD, CAC, or carotid IMT in either men or women. In longitudinal analyses in males, the carriers of heterozygous genotypes (-219G/T or +113G/C) and, furthermore, carriers of the -219T/+113C/epsilon3 haplotype had significantly higher LDL-C and total cholesterol concentrations throughout the 21 year follow-up period compared with homozygous G allele carriers or noncarriers of the -219T/+113C/epsilon3 haplotype. Such associations were not found in females. In summary, the APOE promoter polymorphisms -219G/T and +113G/C as well as their haplotype are associated with longitudinal changes in LDL-C and total cholesterol concentrations in young Finnish males but do not seem to be major determinants for FMD, CAC, or carotid IMT in males or females.     

Increased serum butyrylcholinesterase activity in type IIb hyperlipidaemic patients

The inheritance of the apolipoprotein E4 (APOE4) allele has been shown to increase the plasma cholesterol level, but little information is as concerns the association of the APOE genotype and hyperlipidaemia and the activities of two serum enzymes, acetylcholinesterase (AChE) and butyrylcholinesterase (BChE). Blood samples from 55 type IIb hyperlipidaemic, non-demented patients and 55 age- and sex-matched controls were therefore examined in this pilot study. A significantly increased BChE activity was found in the serum of type IIb hyperlipidaemic patients, but the AChE activity did not differ significantly as compared with that in the control group. The APOE4 allele was significantly overrepresented among the hyperlipidaemic probands, but neither serum cholinesterase activity was affected by the dosage of the APOE4 gene. Our results point to a possible association between an abnormal lipid metabolism and the BChE activity and might have implications as regards the pathomechanism of both Alzheimer's and vascular dementias and the cholinesterase inhibitor therapy of dementing disorders.     

Apolipoprotein E genotyping among the healthy Kuwaiti population

Apolipoproteins (lipid-free) are lipid-binding proteins that circulate in the plasma of human blood and are responsible for the clearance of lipoproteins. Apolipoprotein E (ApoE) is one of the several classes of this protein family. It acts as a ligand for the low-density lipid (LDL) receptors and is important for the clearance of very low-density lipid (VLDL) and chylomicron remnants. The APOE gene locus is polymorphic, with three major known alleles, APOE*3, *4, and *2. We investigated the distribution of the allele frequency of the APOE gene locus and describe here the genetic variation in four Kuwaiti subpopulations: Arab origin (Arabian peninsula), Arab Bedouin tribes, Iranian origin, and the heterogeneous population. We also describe the use of Spreadex gels in resolving the amplified and digested products of the APOE gene locus. DNA was extracted from whole blood and subjected to PCR and then to RFLP analysis. Allele and genotype frequencies were estimated for the total population and for each subpopulation. Statistical analysis showed no difference in the allele frequencies between the four groups. The frequency of APOE*3 in the Kuwaiti population was highest (88.4%) followed by the frequency of APOE*4 (6.5%) and APOE*2 (5.1%). The genotype and allele frequencies obtained for the Kuwaiti population fell within the reported worldwide distribution for the APOE gene locus. Moreover, the results obtained in this study showed no statistical difference (p > 0.05) between the APOE allele and genotype frequencies between the subgroups for all six genotypes and three alleles, supporting the assumption of admixture in the Kuwaiti population and that the obtained frequencies were in Hardy-Weinberg equilibrium. Finally, we found that the distribution of the APOE alleles in Kuwait differs somewhat from those reported in other Arab populations, suggesting that the Arabs originating from the Arabian peninsula are different from those of Lebanon, Morocco, and Sudan.     

Circulating Insulin Concentrations,Smoking, and Alcohol Intake Are Important Independent Predictors of Leptin in Young Healthy Men

Objective : Leptin, an adipocyte-secreted hormone, has been shown to signal the status of energy stores to the brain, regulate energy homeostasis, and mediate the neuroendocrine response to food deprivation. Obesity is associated with increased leptin levels, and several hormones, including insulin and glucocorticoids, have been associated with leptin levels and expression in rodents. Although obesity has been strongly associated with increased leptin in humans, a significant percentage of leptin's variability remains unexplained. The role of endogenous hormones, demographic factors, or certain life-style factors in explaining the residual variability of leptin levels has not yet been clarified. We performed this cross-sectional study to document the relative importance of obesity, lifestyle factor, and endogenous hormones in determining serum leptin levels. Research Methods and Procedures : We measured serum concentrations of insulin, Cortisol, testosterone, growth hormone, and dehydroepiandrosterone sulfate; ascertained anthropometric, demographic, and lifestyle characteristics; and studied these variables in relationship to serum leptin concentrations in a sample of young healthy men. Results : Obesity and alcohol intake were independently and positively associated with circulating leptin concentrations. Additionally, cigarette smoking was negatively and independently associated with leptin concentrations. Finally, serum insulin concentration was an independent hormonal determinant of circulating leptin concentrations, whereas serum testosterone was negatively associated with leptin only by bivariate analysis. Discussion : We conclude that, in addition to obesity, cigarette smoking, alcohol intake, and serum insulin levels are associated with leptin levels in a population of healthy young men.     

Associations between Apolipoprotein E Genotype, Diet, Body Mass Index, and Serum Lipids in Lithuanian Adult Population

Background

Apolipoprotein E (APOE) polymorphism is associated with lipid levels. Some studies have reported that blood lipid response to diet or obesity varies depending on APOE genotypes. The aim of this study was to assess the effect of APOE genotypes, the intake of saturated fatty acids (SFA), and obesity on serum lipid levels in Lithuanian adult population.

Methodology/Principal Findings

A cross-sectional health survey was carried out in five municipalities of Lithuania. The random sample was obtained from lists of 25–64 year-old inhabitants registered at primary health care centres. The data from 996 subjects (416 men and 580 women) were analysed in this study. Two single-nucleotide polymorphisms (rs429358 and rs7412) were assessed using a real-time polymerase chain reaction. 24-hour recall and food frequency questionnaire were used for evaluation of dietary habits. Serum lipids were determined using enzymatic methods.Men and women with the APOE2 genotype had the lowest level of total cholesterol (TC) (p = 0.002 for men, and p = 0.02 for women) and low-density lipoprotein cholesterol (LDL-C) (p<0.001). Multivariate linear regression analysis showed that age, genotype APOE2, SFA intake, and body mass index (BMI) were significant determinants of TC and LDL-C level (with p values ranging from 0.043 to 0.001). Our data did not reveal any statistically significant interactions between APOE genotype and SFA intake or between APOE genotype and BMI regarding TC and LDL-C level (all p>0.05). However, the predictive power of the regression model for LDL-C improved when gene-BMI interaction and gene-BMI interaction plus gene-nutrient interaction were added (p = 0.04 and p = 0.032 for R² change, respectively).

Conclusions/Significance

APOE genotypes, SFA intake, and obesity were found to be associated with blood lipid levels in Lithuanian adult population. Analysis of gene-diet and gene-obesity interactions did not confirm that the effects of diet and obesity on TC and LDL-C level significantly depended on APOE genotype.     

Genetic variants of the lipoprotein lipase gene and myocardial infarction in the Central Valley of Costa Rica

To assess common variants of the LPL gene that could influence susceptibility to myocardial infarction (MI), we assessed three functional single-nucleotide polymorphisms (SNPs), D9N, N291S, and S447X, in 1,321 survivors of a first acute MI and 1,321 population-based controls, matched for age, gender, and area of residence, all living in the Central Valley of Costa Rica. Conditional logistic regression was used to estimate odds ratio (OR) and 95% confidence interval (CI). The frequency of the X447 mutant allele was significantly lower in cases than in controls (6.2% vs. 7.6%; P < 0.01), whereas no association with MI was found for D9N or N291S. The OR (95% CI) for carriers vs. noncarriers of the X447 allele was 0.80 (0.63-1.01); when considering the haplotype that contained X447 and normal alleles of D9N and N291S, the OR (95% CI) was 0.66 (0.48-0.91). Twelve other SNPs were assessed in a subgroup of the population, of which the four functional SNPs were found to be monomorphic, and no correlation with MI was observed for the other eight neutral SNPs. The X447 mutant allele of the LPL gene may protect from MI risk, although this effect is small.